Introduce Makefile and go vendor directory for faster build (#67)

vendor/cloud.google.com/go/LICENSE

@@ -0,0 +1,202 @@
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vendor/cloud.google.com/go/compute/metadata/metadata.go

@@ -0,0 +1,513 @@
+// Copyright 2014 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package metadata provides access to Google Compute Engine (GCE)
+// metadata and API service accounts.
+//
+// This package is a wrapper around the GCE metadata service,
+// as documented at https://developers.google.com/compute/docs/metadata.
+package metadata // import "cloud.google.com/go/compute/metadata"
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"net"
+	"net/http"
+	"net/url"
+	"os"
+	"runtime"
+	"strings"
+	"sync"
+	"time"
+)
+
+const (
+	// metadataIP is the documented metadata server IP address.
+	metadataIP = "169.254.169.254"
+
+	// metadataHostEnv is the environment variable specifying the
+	// GCE metadata hostname.  If empty, the default value of
+	// metadataIP ("169.254.169.254") is used instead.
+	// This is variable name is not defined by any spec, as far as
+	// I know; it was made up for the Go package.
+	metadataHostEnv = "GCE_METADATA_HOST"
+
+	userAgent = "gcloud-golang/0.1"
+)
+
+type cachedValue struct {
+	k    string
+	trim bool
+	mu   sync.Mutex
+	v    string
+}
+
+var (
+	projID  = &cachedValue{k: "project/project-id", trim: true}
+	projNum = &cachedValue{k: "project/numeric-project-id", trim: true}
+	instID  = &cachedValue{k: "instance/id", trim: true}
+)
+
+var (
+	defaultClient = &Client{hc: &http.Client{
+		Transport: &http.Transport{
+			Dial: (&net.Dialer{
+				Timeout:   2 * time.Second,
+				KeepAlive: 30 * time.Second,
+			}).Dial,
+			ResponseHeaderTimeout: 2 * time.Second,
+		},
+	}}
+	subscribeClient = &Client{hc: &http.Client{
+		Transport: &http.Transport{
+			Dial: (&net.Dialer{
+				Timeout:   2 * time.Second,
+				KeepAlive: 30 * time.Second,
+			}).Dial,
+		},
+	}}
+)
+
+// NotDefinedError is returned when requested metadata is not defined.
+//
+// The underlying string is the suffix after "/computeMetadata/v1/".
+//
+// This error is not returned if the value is defined to be the empty
+// string.
+type NotDefinedError string
+
+func (suffix NotDefinedError) Error() string {
+	return fmt.Sprintf("metadata: GCE metadata %q not defined", string(suffix))
+}
+
+func (c *cachedValue) get(cl *Client) (v string, err error) {
+	defer c.mu.Unlock()
+	c.mu.Lock()
+	if c.v != "" {
+		return c.v, nil
+	}
+	if c.trim {
+		v, err = cl.getTrimmed(c.k)
+	} else {
+		v, err = cl.Get(c.k)
+	}
+	if err == nil {
+		c.v = v
+	}
+	return
+}
+
+var (
+	onGCEOnce sync.Once
+	onGCE     bool
+)
+
+// OnGCE reports whether this process is running on Google Compute Engine.
+func OnGCE() bool {
+	onGCEOnce.Do(initOnGCE)
+	return onGCE
+}
+
+func initOnGCE() {
+	onGCE = testOnGCE()
+}
+
+func testOnGCE() bool {
+	// The user explicitly said they're on GCE, so trust them.
+	if os.Getenv(metadataHostEnv) != "" {
+		return true
+	}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	resc := make(chan bool, 2)
+
+	// Try two strategies in parallel.
+	// See https://github.com/googleapis/google-cloud-go/issues/194
+	go func() {
+		req, _ := http.NewRequest("GET", "http://"+metadataIP, nil)
+		req.Header.Set("User-Agent", userAgent)
+		res, err := defaultClient.hc.Do(req.WithContext(ctx))
+		if err != nil {
+			resc <- false
+			return
+		}
+		defer res.Body.Close()
+		resc <- res.Header.Get("Metadata-Flavor") == "Google"
+	}()
+
+	go func() {
+		addrs, err := net.LookupHost("metadata.google.internal")
+		if err != nil || len(addrs) == 0 {
+			resc <- false
+			return
+		}
+		resc <- strsContains(addrs, metadataIP)
+	}()
+
+	tryHarder := systemInfoSuggestsGCE()
+	if tryHarder {
+		res := <-resc
+		if res {
+			// The first strategy succeeded, so let's use it.
+			return true
+		}
+		// Wait for either the DNS or metadata server probe to
+		// contradict the other one and say we are running on
+		// GCE. Give it a lot of time to do so, since the system
+		// info already suggests we're running on a GCE BIOS.
+		timer := time.NewTimer(5 * time.Second)
+		defer timer.Stop()
+		select {
+		case res = <-resc:
+			return res
+		case <-timer.C:
+			// Too slow. Who knows what this system is.
+			return false
+		}
+	}
+
+	// There's no hint from the system info that we're running on
+	// GCE, so use the first probe's result as truth, whether it's
+	// true or false. The goal here is to optimize for speed for
+	// users who are NOT running on GCE. We can't assume that
+	// either a DNS lookup or an HTTP request to a blackholed IP
+	// address is fast. Worst case this should return when the
+	// metaClient's Transport.ResponseHeaderTimeout or
+	// Transport.Dial.Timeout fires (in two seconds).
+	return <-resc
+}
+
+// systemInfoSuggestsGCE reports whether the local system (without
+// doing network requests) suggests that we're running on GCE. If this
+// returns true, testOnGCE tries a bit harder to reach its metadata
+// server.
+func systemInfoSuggestsGCE() bool {
+	if runtime.GOOS != "linux" {
+		// We don't have any non-Linux clues available, at least yet.
+		return false
+	}
+	slurp, _ := ioutil.ReadFile("/sys/class/dmi/id/product_name")
+	name := strings.TrimSpace(string(slurp))
+	return name == "Google" || name == "Google Compute Engine"
+}
+
+// Subscribe calls Client.Subscribe on a client designed for subscribing (one with no
+// ResponseHeaderTimeout).
+func Subscribe(suffix string, fn func(v string, ok bool) error) error {
+	return subscribeClient.Subscribe(suffix, fn)
+}
+
+// Get calls Client.Get on the default client.
+func Get(suffix string) (string, error) { return defaultClient.Get(suffix) }
+
+// ProjectID returns the current instance's project ID string.
+func ProjectID() (string, error) { return defaultClient.ProjectID() }
+
+// NumericProjectID returns the current instance's numeric project ID.
+func NumericProjectID() (string, error) { return defaultClient.NumericProjectID() }
+
+// InternalIP returns the instance's primary internal IP address.
+func InternalIP() (string, error) { return defaultClient.InternalIP() }
+
+// ExternalIP returns the instance's primary external (public) IP address.
+func ExternalIP() (string, error) { return defaultClient.ExternalIP() }
+
+// Hostname returns the instance's hostname. This will be of the form
+// "<instanceID>.c.<projID>.internal".
+func Hostname() (string, error) { return defaultClient.Hostname() }
+
+// InstanceTags returns the list of user-defined instance tags,
+// assigned when initially creating a GCE instance.
+func InstanceTags() ([]string, error) { return defaultClient.InstanceTags() }
+
+// InstanceID returns the current VM's numeric instance ID.
+func InstanceID() (string, error) { return defaultClient.InstanceID() }
+
+// InstanceName returns the current VM's instance ID string.
+func InstanceName() (string, error) { return defaultClient.InstanceName() }
+
+// Zone returns the current VM's zone, such as "us-central1-b".
+func Zone() (string, error) { return defaultClient.Zone() }
+
+// InstanceAttributes calls Client.InstanceAttributes on the default client.
+func InstanceAttributes() ([]string, error) { return defaultClient.InstanceAttributes() }
+
+// ProjectAttributes calls Client.ProjectAttributes on the default client.
+func ProjectAttributes() ([]string, error) { return defaultClient.ProjectAttributes() }
+
+// InstanceAttributeValue calls Client.InstanceAttributeValue on the default client.
+func InstanceAttributeValue(attr string) (string, error) {
+	return defaultClient.InstanceAttributeValue(attr)
+}
+
+// ProjectAttributeValue calls Client.ProjectAttributeValue on the default client.
+func ProjectAttributeValue(attr string) (string, error) {
+	return defaultClient.ProjectAttributeValue(attr)
+}
+
+// Scopes calls Client.Scopes on the default client.
+func Scopes(serviceAccount string) ([]string, error) { return defaultClient.Scopes(serviceAccount) }
+
+func strsContains(ss []string, s string) bool {
+	for _, v := range ss {
+		if v == s {
+			return true
+		}
+	}
+	return false
+}
+
+// A Client provides metadata.
+type Client struct {
+	hc *http.Client
+}
+
+// NewClient returns a Client that can be used to fetch metadata. All HTTP requests
+// will use the given http.Client instead of the default client.
+func NewClient(c *http.Client) *Client {
+	return &Client{hc: c}
+}
+
+// getETag returns a value from the metadata service as well as the associated ETag.
+// This func is otherwise equivalent to Get.
+func (c *Client) getETag(suffix string) (value, etag string, err error) {
+	// Using a fixed IP makes it very difficult to spoof the metadata service in
+	// a container, which is an important use-case for local testing of cloud
+	// deployments. To enable spoofing of the metadata service, the environment
+	// variable GCE_METADATA_HOST is first inspected to decide where metadata
+	// requests shall go.
+	host := os.Getenv(metadataHostEnv)
+	if host == "" {
+		// Using 169.254.169.254 instead of "metadata" here because Go
+		// binaries built with the "netgo" tag and without cgo won't
+		// know the search suffix for "metadata" is
+		// ".google.internal", and this IP address is documented as
+		// being stable anyway.
+		host = metadataIP
+	}
+	u := "http://" + host + "/computeMetadata/v1/" + suffix
+	req, _ := http.NewRequest("GET", u, nil)
+	req.Header.Set("Metadata-Flavor", "Google")
+	req.Header.Set("User-Agent", userAgent)
+	res, err := c.hc.Do(req)
+	if err != nil {
+		return "", "", err
+	}
+	defer res.Body.Close()
+	if res.StatusCode == http.StatusNotFound {
+		return "", "", NotDefinedError(suffix)
+	}
+	all, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		return "", "", err
+	}
+	if res.StatusCode != 200 {
+		return "", "", &Error{Code: res.StatusCode, Message: string(all)}
+	}
+	return string(all), res.Header.Get("Etag"), nil
+}
+
+// Get returns a value from the metadata service.
+// The suffix is appended to "http://${GCE_METADATA_HOST}/computeMetadata/v1/".
+//
+// If the GCE_METADATA_HOST environment variable is not defined, a default of
+// 169.254.169.254 will be used instead.
+//
+// If the requested metadata is not defined, the returned error will
+// be of type NotDefinedError.
+func (c *Client) Get(suffix string) (string, error) {
+	val, _, err := c.getETag(suffix)
+	return val, err
+}
+
+func (c *Client) getTrimmed(suffix string) (s string, err error) {
+	s, err = c.Get(suffix)
+	s = strings.TrimSpace(s)
+	return
+}
+
+func (c *Client) lines(suffix string) ([]string, error) {
+	j, err := c.Get(suffix)
+	if err != nil {
+		return nil, err
+	}
+	s := strings.Split(strings.TrimSpace(j), "\n")
+	for i := range s {
+		s[i] = strings.TrimSpace(s[i])
+	}
+	return s, nil
+}
+
+// ProjectID returns the current instance's project ID string.
+func (c *Client) ProjectID() (string, error) { return projID.get(c) }
+
+// NumericProjectID returns the current instance's numeric project ID.
+func (c *Client) NumericProjectID() (string, error) { return projNum.get(c) }
+
+// InstanceID returns the current VM's numeric instance ID.
+func (c *Client) InstanceID() (string, error) { return instID.get(c) }
+
+// InternalIP returns the instance's primary internal IP address.
+func (c *Client) InternalIP() (string, error) {
+	return c.getTrimmed("instance/network-interfaces/0/ip")
+}
+
+// ExternalIP returns the instance's primary external (public) IP address.
+func (c *Client) ExternalIP() (string, error) {
+	return c.getTrimmed("instance/network-interfaces/0/access-configs/0/external-ip")
+}
+
+// Hostname returns the instance's hostname. This will be of the form
+// "<instanceID>.c.<projID>.internal".
+func (c *Client) Hostname() (string, error) {
+	return c.getTrimmed("instance/hostname")
+}
+
+// InstanceTags returns the list of user-defined instance tags,
+// assigned when initially creating a GCE instance.
+func (c *Client) InstanceTags() ([]string, error) {
+	var s []string
+	j, err := c.Get("instance/tags")
+	if err != nil {
+		return nil, err
+	}
+	if err := json.NewDecoder(strings.NewReader(j)).Decode(&s); err != nil {
+		return nil, err
+	}
+	return s, nil
+}
+
+// InstanceName returns the current VM's instance ID string.
+func (c *Client) InstanceName() (string, error) {
+	host, err := c.Hostname()
+	if err != nil {
+		return "", err
+	}
+	return strings.Split(host, ".")[0], nil
+}
+
+// Zone returns the current VM's zone, such as "us-central1-b".
+func (c *Client) Zone() (string, error) {
+	zone, err := c.getTrimmed("instance/zone")
+	// zone is of the form "projects/<projNum>/zones/<zoneName>".
+	if err != nil {
+		return "", err
+	}
+	return zone[strings.LastIndex(zone, "/")+1:], nil
+}
+
+// InstanceAttributes returns the list of user-defined attributes,
+// assigned when initially creating a GCE VM instance. The value of an
+// attribute can be obtained with InstanceAttributeValue.
+func (c *Client) InstanceAttributes() ([]string, error) { return c.lines("instance/attributes/") }
+
+// ProjectAttributes returns the list of user-defined attributes
+// applying to the project as a whole, not just this VM.  The value of
+// an attribute can be obtained with ProjectAttributeValue.
+func (c *Client) ProjectAttributes() ([]string, error) { return c.lines("project/attributes/") }
+
+// InstanceAttributeValue returns the value of the provided VM
+// instance attribute.
+//
+// If the requested attribute is not defined, the returned error will
+// be of type NotDefinedError.
+//
+// InstanceAttributeValue may return ("", nil) if the attribute was
+// defined to be the empty string.
+func (c *Client) InstanceAttributeValue(attr string) (string, error) {
+	return c.Get("instance/attributes/" + attr)
+}
+
+// ProjectAttributeValue returns the value of the provided
+// project attribute.
+//
+// If the requested attribute is not defined, the returned error will
+// be of type NotDefinedError.
+//
+// ProjectAttributeValue may return ("", nil) if the attribute was
+// defined to be the empty string.
+func (c *Client) ProjectAttributeValue(attr string) (string, error) {
+	return c.Get("project/attributes/" + attr)
+}
+
+// Scopes returns the service account scopes for the given account.
+// The account may be empty or the string "default" to use the instance's
+// main account.
+func (c *Client) Scopes(serviceAccount string) ([]string, error) {
+	if serviceAccount == "" {
+		serviceAccount = "default"
+	}
+	return c.lines("instance/service-accounts/" + serviceAccount + "/scopes")
+}
+
+// Subscribe subscribes to a value from the metadata service.
+// The suffix is appended to "http://${GCE_METADATA_HOST}/computeMetadata/v1/".
+// The suffix may contain query parameters.
+//
+// Subscribe calls fn with the latest metadata value indicated by the provided
+// suffix. If the metadata value is deleted, fn is called with the empty string
+// and ok false. Subscribe blocks until fn returns a non-nil error or the value
+// is deleted. Subscribe returns the error value returned from the last call to
+// fn, which may be nil when ok == false.
+func (c *Client) Subscribe(suffix string, fn func(v string, ok bool) error) error {
+	const failedSubscribeSleep = time.Second * 5
+
+	// First check to see if the metadata value exists at all.
+	val, lastETag, err := c.getETag(suffix)
+	if err != nil {
+		return err
+	}
+
+	if err := fn(val, true); err != nil {
+		return err
+	}
+
+	ok := true
+	if strings.ContainsRune(suffix, '?') {
+		suffix += "&wait_for_change=true&last_etag="
+	} else {
+		suffix += "?wait_for_change=true&last_etag="
+	}
+	for {
+		val, etag, err := c.getETag(suffix + url.QueryEscape(lastETag))
+		if err != nil {
+			if _, deleted := err.(NotDefinedError); !deleted {
+				time.Sleep(failedSubscribeSleep)
+				continue // Retry on other errors.
+			}
+			ok = false
+		}
+		lastETag = etag
+
+		if err := fn(val, ok); err != nil || !ok {
+			return err
+		}
+	}
+}
+
+// Error contains an error response from the server.
+type Error struct {
+	// Code is the HTTP response status code.
+	Code int
+	// Message is the server response message.
+	Message string
+}
+
+func (e *Error) Error() string {
+	return fmt.Sprintf("compute: Received %d `%s`", e.Code, e.Message)
+}

vendor/cloud.google.com/go/iam/iam.go

@@ -0,0 +1,315 @@
+// Copyright 2016 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package iam supports the resource-specific operations of Google Cloud
+// IAM (Identity and Access Management) for the Google Cloud Libraries.
+// See https://cloud.google.com/iam for more about IAM.
+//
+// Users of the Google Cloud Libraries will typically not use this package
+// directly. Instead they will begin with some resource that supports IAM, like
+// a pubsub topic, and call its IAM method to get a Handle for that resource.
+package iam
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	gax "github.com/googleapis/gax-go/v2"
+	pb "google.golang.org/genproto/googleapis/iam/v1"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/metadata"
+)
+
+// client abstracts the IAMPolicy API to allow multiple implementations.
+type client interface {
+	Get(ctx context.Context, resource string) (*pb.Policy, error)
+	Set(ctx context.Context, resource string, p *pb.Policy) error
+	Test(ctx context.Context, resource string, perms []string) ([]string, error)
+}
+
+// grpcClient implements client for the standard gRPC-based IAMPolicy service.
+type grpcClient struct {
+	c pb.IAMPolicyClient
+}
+
+var withRetry = gax.WithRetry(func() gax.Retryer {
+	return gax.OnCodes([]codes.Code{
+		codes.DeadlineExceeded,
+		codes.Unavailable,
+	}, gax.Backoff{
+		Initial:    100 * time.Millisecond,
+		Max:        60 * time.Second,
+		Multiplier: 1.3,
+	})
+})
+
+func (g *grpcClient) Get(ctx context.Context, resource string) (*pb.Policy, error) {
+	var proto *pb.Policy
+	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "resource", resource))
+	ctx = insertMetadata(ctx, md)
+
+	err := gax.Invoke(ctx, func(ctx context.Context, _ gax.CallSettings) error {
+		var err error
+		proto, err = g.c.GetIamPolicy(ctx, &pb.GetIamPolicyRequest{Resource: resource})
+		return err
+	}, withRetry)
+	if err != nil {
+		return nil, err
+	}
+	return proto, nil
+}
+
+func (g *grpcClient) Set(ctx context.Context, resource string, p *pb.Policy) error {
+	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "resource", resource))
+	ctx = insertMetadata(ctx, md)
+
+	return gax.Invoke(ctx, func(ctx context.Context, _ gax.CallSettings) error {
+		_, err := g.c.SetIamPolicy(ctx, &pb.SetIamPolicyRequest{
+			Resource: resource,
+			Policy:   p,
+		})
+		return err
+	}, withRetry)
+}
+
+func (g *grpcClient) Test(ctx context.Context, resource string, perms []string) ([]string, error) {
+	var res *pb.TestIamPermissionsResponse
+	md := metadata.Pairs("x-goog-request-params", fmt.Sprintf("%s=%v", "resource", resource))
+	ctx = insertMetadata(ctx, md)
+
+	err := gax.Invoke(ctx, func(ctx context.Context, _ gax.CallSettings) error {
+		var err error
+		res, err = g.c.TestIamPermissions(ctx, &pb.TestIamPermissionsRequest{
+			Resource:    resource,
+			Permissions: perms,
+		})
+		return err
+	}, withRetry)
+	if err != nil {
+		return nil, err
+	}
+	return res.Permissions, nil
+}
+
+// A Handle provides IAM operations for a resource.
+type Handle struct {
+	c        client
+	resource string
+}
+
+// InternalNewHandle is for use by the Google Cloud Libraries only.
+//
+// InternalNewHandle returns a Handle for resource.
+// The conn parameter refers to a server that must support the IAMPolicy service.
+func InternalNewHandle(conn *grpc.ClientConn, resource string) *Handle {
+	return InternalNewHandleGRPCClient(pb.NewIAMPolicyClient(conn), resource)
+}
+
+// InternalNewHandleGRPCClient is for use by the Google Cloud Libraries only.
+//
+// InternalNewHandleClient returns a Handle for resource using the given
+// grpc service that implements IAM as a mixin
+func InternalNewHandleGRPCClient(c pb.IAMPolicyClient, resource string) *Handle {
+	return InternalNewHandleClient(&grpcClient{c: c}, resource)
+}
+
+// InternalNewHandleClient is for use by the Google Cloud Libraries only.
+//
+// InternalNewHandleClient returns a Handle for resource using the given
+// client implementation.
+func InternalNewHandleClient(c client, resource string) *Handle {
+	return &Handle{
+		c:        c,
+		resource: resource,
+	}
+}
+
+// Policy retrieves the IAM policy for the resource.
+func (h *Handle) Policy(ctx context.Context) (*Policy, error) {
+	proto, err := h.c.Get(ctx, h.resource)
+	if err != nil {
+		return nil, err
+	}
+	return &Policy{InternalProto: proto}, nil
+}
+
+// SetPolicy replaces the resource's current policy with the supplied Policy.
+//
+// If policy was created from a prior call to Get, then the modification will
+// only succeed if the policy has not changed since the Get.
+func (h *Handle) SetPolicy(ctx context.Context, policy *Policy) error {
+	return h.c.Set(ctx, h.resource, policy.InternalProto)
+}
+
+// TestPermissions returns the subset of permissions that the caller has on the resource.
+func (h *Handle) TestPermissions(ctx context.Context, permissions []string) ([]string, error) {
+	return h.c.Test(ctx, h.resource, permissions)
+}
+
+// A RoleName is a name representing a collection of permissions.
+type RoleName string
+
+// Common role names.
+const (
+	Owner  RoleName = "roles/owner"
+	Editor RoleName = "roles/editor"
+	Viewer RoleName = "roles/viewer"
+)
+
+const (
+	// AllUsers is a special member that denotes all users, even unauthenticated ones.
+	AllUsers = "allUsers"
+
+	// AllAuthenticatedUsers is a special member that denotes all authenticated users.
+	AllAuthenticatedUsers = "allAuthenticatedUsers"
+)
+
+// A Policy is a list of Bindings representing roles
+// granted to members.
+//
+// The zero Policy is a valid policy with no bindings.
+type Policy struct {
+	// TODO(jba): when type aliases are available, put Policy into an internal package
+	// and provide an exported alias here.
+
+	// This field is exported for use by the Google Cloud Libraries only.
+	// It may become unexported in a future release.
+	InternalProto *pb.Policy
+}
+
+// Members returns the list of members with the supplied role.
+// The return value should not be modified. Use Add and Remove
+// to modify the members of a role.
+func (p *Policy) Members(r RoleName) []string {
+	b := p.binding(r)
+	if b == nil {
+		return nil
+	}
+	return b.Members
+}
+
+// HasRole reports whether member has role r.
+func (p *Policy) HasRole(member string, r RoleName) bool {
+	return memberIndex(member, p.binding(r)) >= 0
+}
+
+// Add adds member member to role r if it is not already present.
+// A new binding is created if there is no binding for the role.
+func (p *Policy) Add(member string, r RoleName) {
+	b := p.binding(r)
+	if b == nil {
+		if p.InternalProto == nil {
+			p.InternalProto = &pb.Policy{}
+		}
+		p.InternalProto.Bindings = append(p.InternalProto.Bindings, &pb.Binding{
+			Role:    string(r),
+			Members: []string{member},
+		})
+		return
+	}
+	if memberIndex(member, b) < 0 {
+		b.Members = append(b.Members, member)
+		return
+	}
+}
+
+// Remove removes member from role r if it is present.
+func (p *Policy) Remove(member string, r RoleName) {
+	bi := p.bindingIndex(r)
+	if bi < 0 {
+		return
+	}
+	bindings := p.InternalProto.Bindings
+	b := bindings[bi]
+	mi := memberIndex(member, b)
+	if mi < 0 {
+		return
+	}
+	// Order doesn't matter for bindings or members, so to remove, move the last item
+	// into the removed spot and shrink the slice.
+	if len(b.Members) == 1 {
+		// Remove binding.
+		last := len(bindings) - 1
+		bindings[bi] = bindings[last]
+		bindings[last] = nil
+		p.InternalProto.Bindings = bindings[:last]
+		return
+	}
+	// Remove member.
+	// TODO(jba): worry about multiple copies of m?
+	last := len(b.Members) - 1
+	b.Members[mi] = b.Members[last]
+	b.Members[last] = ""
+	b.Members = b.Members[:last]
+}
+
+// Roles returns the names of all the roles that appear in the Policy.
+func (p *Policy) Roles() []RoleName {
+	if p.InternalProto == nil {
+		return nil
+	}
+	var rns []RoleName
+	for _, b := range p.InternalProto.Bindings {
+		rns = append(rns, RoleName(b.Role))
+	}
+	return rns
+}
+
+// binding returns the Binding for the suppied role, or nil if there isn't one.
+func (p *Policy) binding(r RoleName) *pb.Binding {
+	i := p.bindingIndex(r)
+	if i < 0 {
+		return nil
+	}
+	return p.InternalProto.Bindings[i]
+}
+
+func (p *Policy) bindingIndex(r RoleName) int {
+	if p.InternalProto == nil {
+		return -1
+	}
+	for i, b := range p.InternalProto.Bindings {
+		if b.Role == string(r) {
+			return i
+		}
+	}
+	return -1
+}
+
+// memberIndex returns the index of m in b's Members, or -1 if not found.
+func memberIndex(m string, b *pb.Binding) int {
+	if b == nil {
+		return -1
+	}
+	for i, mm := range b.Members {
+		if mm == m {
+			return i
+		}
+	}
+	return -1
+}
+
+// insertMetadata inserts metadata into the given context
+func insertMetadata(ctx context.Context, mds ...metadata.MD) context.Context {
+	out, _ := metadata.FromOutgoingContext(ctx)
+	out = out.Copy()
+	for _, md := range mds {
+		for k, v := range md {
+			out[k] = append(out[k], v...)
+		}
+	}
+	return metadata.NewOutgoingContext(ctx, out)
+}

vendor/cloud.google.com/go/internal/annotate.go

@@ -0,0 +1,54 @@
+// Copyright 2017 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package internal
+
+import (
+	"fmt"
+
+	"google.golang.org/api/googleapi"
+	"google.golang.org/grpc/status"
+)
+
+// Annotate prepends msg to the error message in err, attempting
+// to preserve other information in err, like an error code.
+//
+// Annotate panics if err is nil.
+//
+// Annotate knows about these error types:
+// - "google.golang.org/grpc/status".Status
+// - "google.golang.org/api/googleapi".Error
+// If the error is not one of these types, Annotate behaves
+// like
+//   fmt.Errorf("%s: %v", msg, err)
+func Annotate(err error, msg string) error {
+	if err == nil {
+		panic("Annotate called with nil")
+	}
+	if s, ok := status.FromError(err); ok {
+		p := s.Proto()
+		p.Message = msg + ": " + p.Message
+		return status.ErrorProto(p)
+	}
+	if g, ok := err.(*googleapi.Error); ok {
+		g.Message = msg + ": " + g.Message
+		return g
+	}
+	return fmt.Errorf("%s: %v", msg, err)
+}
+
+// Annotatef uses format and args to format a string, then calls Annotate.
+func Annotatef(err error, format string, args ...interface{}) error {
+	return Annotate(err, fmt.Sprintf(format, args...))
+}

vendor/cloud.google.com/go/internal/optional/optional.go

@@ -0,0 +1,108 @@
+// Copyright 2016 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package optional provides versions of primitive types that can
+// be nil. These are useful in methods that update some of an API object's
+// fields.
+package optional
+
+import (
+	"fmt"
+	"strings"
+	"time"
+)
+
+type (
+	// Bool is either a bool or nil.
+	Bool interface{}
+
+	// String is either a string or nil.
+	String interface{}
+
+	// Int is either an int or nil.
+	Int interface{}
+
+	// Uint is either a uint or nil.
+	Uint interface{}
+
+	// Float64 is either a float64 or nil.
+	Float64 interface{}
+
+	// Duration is either a time.Duration or nil.
+	Duration interface{}
+)
+
+// ToBool returns its argument as a bool.
+// It panics if its argument is nil or not a bool.
+func ToBool(v Bool) bool {
+	x, ok := v.(bool)
+	if !ok {
+		doPanic("Bool", v)
+	}
+	return x
+}
+
+// ToString returns its argument as a string.
+// It panics if its argument is nil or not a string.
+func ToString(v String) string {
+	x, ok := v.(string)
+	if !ok {
+		doPanic("String", v)
+	}
+	return x
+}
+
+// ToInt returns its argument as an int.
+// It panics if its argument is nil or not an int.
+func ToInt(v Int) int {
+	x, ok := v.(int)
+	if !ok {
+		doPanic("Int", v)
+	}
+	return x
+}
+
+// ToUint returns its argument as a uint.
+// It panics if its argument is nil or not a uint.
+func ToUint(v Uint) uint {
+	x, ok := v.(uint)
+	if !ok {
+		doPanic("Uint", v)
+	}
+	return x
+}
+
+// ToFloat64 returns its argument as a float64.
+// It panics if its argument is nil or not a float64.
+func ToFloat64(v Float64) float64 {
+	x, ok := v.(float64)
+	if !ok {
+		doPanic("Float64", v)
+	}
+	return x
+}
+
+// ToDuration returns its argument as a time.Duration.
+// It panics if its argument is nil or not a time.Duration.
+func ToDuration(v Duration) time.Duration {
+	x, ok := v.(time.Duration)
+	if !ok {
+		doPanic("Duration", v)
+	}
+	return x
+}
+
+func doPanic(capType string, v interface{}) {
+	panic(fmt.Sprintf("optional.%s value should be %s, got %T", capType, strings.ToLower(capType), v))
+}

vendor/cloud.google.com/go/internal/retry.go

@@ -0,0 +1,54 @@
+// Copyright 2016 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package internal
+
+import (
+	"context"
+	"time"
+
+	gax "github.com/googleapis/gax-go/v2"
+)
+
+// Retry calls the supplied function f repeatedly according to the provided
+// backoff parameters. It returns when one of the following occurs:
+// When f's first return value is true, Retry immediately returns with f's second
+// return value.
+// When the provided context is done, Retry returns with an error that
+// includes both ctx.Error() and the last error returned by f.
+func Retry(ctx context.Context, bo gax.Backoff, f func() (stop bool, err error)) error {
+	return retry(ctx, bo, f, gax.Sleep)
+}
+
+func retry(ctx context.Context, bo gax.Backoff, f func() (stop bool, err error),
+	sleep func(context.Context, time.Duration) error) error {
+	var lastErr error
+	for {
+		stop, err := f()
+		if stop {
+			return err
+		}
+		// Remember the last "real" error from f.
+		if err != nil && err != context.Canceled && err != context.DeadlineExceeded {
+			lastErr = err
+		}
+		p := bo.Pause()
+		if cerr := sleep(ctx, p); cerr != nil {
+			if lastErr != nil {
+				return Annotatef(lastErr, "retry failed with %v; last error", cerr)
+			}
+			return cerr
+		}
+	}
+}

vendor/cloud.google.com/go/internal/trace/trace.go

@@ -0,0 +1,109 @@
+// Copyright 2018 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package trace
+
+import (
+	"context"
+	"fmt"
+
+	"go.opencensus.io/trace"
+	"google.golang.org/api/googleapi"
+	"google.golang.org/genproto/googleapis/rpc/code"
+	"google.golang.org/grpc/status"
+)
+
+// StartSpan adds a span to the trace with the given name.
+func StartSpan(ctx context.Context, name string) context.Context {
+	ctx, _ = trace.StartSpan(ctx, name)
+	return ctx
+}
+
+// EndSpan ends a span with the given error.
+func EndSpan(ctx context.Context, err error) {
+	span := trace.FromContext(ctx)
+	if err != nil {
+		span.SetStatus(toStatus(err))
+	}
+	span.End()
+}
+
+// toStatus interrogates an error and converts it to an appropriate
+// OpenCensus status.
+func toStatus(err error) trace.Status {
+	if err2, ok := err.(*googleapi.Error); ok {
+		return trace.Status{Code: httpStatusCodeToOCCode(err2.Code), Message: err2.Message}
+	} else if s, ok := status.FromError(err); ok {
+		return trace.Status{Code: int32(s.Code()), Message: s.Message()}
+	} else {
+		return trace.Status{Code: int32(code.Code_UNKNOWN), Message: err.Error()}
+	}
+}
+
+// TODO(deklerk): switch to using OpenCensus function when it becomes available.
+// Reference: https://github.com/googleapis/googleapis/blob/26b634d2724ac5dd30ae0b0cbfb01f07f2e4050e/google/rpc/code.proto
+func httpStatusCodeToOCCode(httpStatusCode int) int32 {
+	switch httpStatusCode {
+	case 200:
+		return int32(code.Code_OK)
+	case 499:
+		return int32(code.Code_CANCELLED)
+	case 500:
+		return int32(code.Code_UNKNOWN) // Could also be Code_INTERNAL, Code_DATA_LOSS
+	case 400:
+		return int32(code.Code_INVALID_ARGUMENT) // Could also be Code_OUT_OF_RANGE
+	case 504:
+		return int32(code.Code_DEADLINE_EXCEEDED)
+	case 404:
+		return int32(code.Code_NOT_FOUND)
+	case 409:
+		return int32(code.Code_ALREADY_EXISTS) // Could also be Code_ABORTED
+	case 403:
+		return int32(code.Code_PERMISSION_DENIED)
+	case 401:
+		return int32(code.Code_UNAUTHENTICATED)
+	case 429:
+		return int32(code.Code_RESOURCE_EXHAUSTED)
+	case 501:
+		return int32(code.Code_UNIMPLEMENTED)
+	case 503:
+		return int32(code.Code_UNAVAILABLE)
+	default:
+		return int32(code.Code_UNKNOWN)
+	}
+}
+
+// TODO: (odeke-em): perhaps just pass around spans due to the cost
+// incurred from using trace.FromContext(ctx) yet we could avoid
+// throwing away the work done by ctx, span := trace.StartSpan.
+func TracePrintf(ctx context.Context, attrMap map[string]interface{}, format string, args ...interface{}) {
+	var attrs []trace.Attribute
+	for k, v := range attrMap {
+		var a trace.Attribute
+		switch v := v.(type) {
+		case string:
+			a = trace.StringAttribute(k, v)
+		case bool:
+			a = trace.BoolAttribute(k, v)
+		case int:
+			a = trace.Int64Attribute(k, int64(v))
+		case int64:
+			a = trace.Int64Attribute(k, v)
+		default:
+			a = trace.StringAttribute(k, fmt.Sprintf("%#v", v))
+		}
+		attrs = append(attrs, a)
+	}
+	trace.FromContext(ctx).Annotatef(attrs, format, args...)
+}

vendor/cloud.google.com/go/internal/version/update_version.sh

@@ -0,0 +1,6 @@
+#!/bin/bash
+
+today=$(date +%Y%m%d)
+
+sed -i -r -e 's/const Repo = "([0-9]{8})"/const Repo = "'$today'"/' $GOFILE
+

vendor/cloud.google.com/go/internal/version/version.go

@@ -0,0 +1,71 @@
+// Copyright 2016 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//go:generate ./update_version.sh
+
+// Package version contains version information for Google Cloud Client
+// Libraries for Go, as reported in request headers.
+package version
+
+import (
+	"runtime"
+	"strings"
+	"unicode"
+)
+
+// Repo is the current version of the client libraries in this
+// repo. It should be a date in YYYYMMDD format.
+const Repo = "20180226"
+
+// Go returns the Go runtime version. The returned string
+// has no whitespace.
+func Go() string {
+	return goVersion
+}
+
+var goVersion = goVer(runtime.Version())
+
+const develPrefix = "devel +"
+
+func goVer(s string) string {
+	if strings.HasPrefix(s, develPrefix) {
+		s = s[len(develPrefix):]
+		if p := strings.IndexFunc(s, unicode.IsSpace); p >= 0 {
+			s = s[:p]
+		}
+		return s
+	}
+
+	if strings.HasPrefix(s, "go1") {
+		s = s[2:]
+		var prerelease string
+		if p := strings.IndexFunc(s, notSemverRune); p >= 0 {
+			s, prerelease = s[:p], s[p:]
+		}
+		if strings.HasSuffix(s, ".") {
+			s += "0"
+		} else if strings.Count(s, ".") < 2 {
+			s += ".0"
+		}
+		if prerelease != "" {
+			s += "-" + prerelease
+		}
+		return s
+	}
+	return ""
+}
+
+func notSemverRune(r rune) bool {
+	return !strings.ContainsRune("0123456789.", r)
+}

vendor/cloud.google.com/go/storage/acl.go

@@ -0,0 +1,335 @@
+// Copyright 2014 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package storage
+
+import (
+	"context"
+	"net/http"
+	"reflect"
+
+	"cloud.google.com/go/internal/trace"
+	"google.golang.org/api/googleapi"
+	raw "google.golang.org/api/storage/v1"
+)
+
+// ACLRole is the level of access to grant.
+type ACLRole string
+
+const (
+	RoleOwner  ACLRole = "OWNER"
+	RoleReader ACLRole = "READER"
+	RoleWriter ACLRole = "WRITER"
+)
+
+// ACLEntity refers to a user or group.
+// They are sometimes referred to as grantees.
+//
+// It could be in the form of:
+// "user-<userId>", "user-<email>", "group-<groupId>", "group-<email>",
+// "domain-<domain>" and "project-team-<projectId>".
+//
+// Or one of the predefined constants: AllUsers, AllAuthenticatedUsers.
+type ACLEntity string
+
+const (
+	AllUsers              ACLEntity = "allUsers"
+	AllAuthenticatedUsers ACLEntity = "allAuthenticatedUsers"
+)
+
+// ACLRule represents a grant for a role to an entity (user, group or team) for a
+// Google Cloud Storage object or bucket.
+type ACLRule struct {
+	Entity      ACLEntity
+	EntityID    string
+	Role        ACLRole
+	Domain      string
+	Email       string
+	ProjectTeam *ProjectTeam
+}
+
+// ProjectTeam is the project team associated with the entity, if any.
+type ProjectTeam struct {
+	ProjectNumber string
+	Team          string
+}
+
+// ACLHandle provides operations on an access control list for a Google Cloud Storage bucket or object.
+type ACLHandle struct {
+	c           *Client
+	bucket      string
+	object      string
+	isDefault   bool
+	userProject string // for requester-pays buckets
+}
+
+// Delete permanently deletes the ACL entry for the given entity.
+func (a *ACLHandle) Delete(ctx context.Context, entity ACLEntity) (err error) {
+	ctx = trace.StartSpan(ctx, "cloud.google.com/go/storage.ACL.Delete")
+	defer func() { trace.EndSpan(ctx, err) }()
+
+	if a.object != "" {
+		return a.objectDelete(ctx, entity)
+	}
+	if a.isDefault {
+		return a.bucketDefaultDelete(ctx, entity)
+	}
+	return a.bucketDelete(ctx, entity)
+}
+
+// Set sets the role for the given entity.
+func (a *ACLHandle) Set(ctx context.Context, entity ACLEntity, role ACLRole) (err error) {
+	ctx = trace.StartSpan(ctx, "cloud.google.com/go/storage.ACL.Set")
+	defer func() { trace.EndSpan(ctx, err) }()
+
+	if a.object != "" {
+		return a.objectSet(ctx, entity, role, false)
+	}
+	if a.isDefault {
+		return a.objectSet(ctx, entity, role, true)
+	}
+	return a.bucketSet(ctx, entity, role)
+}
+
+// List retrieves ACL entries.
+func (a *ACLHandle) List(ctx context.Context) (rules []ACLRule, err error) {
+	ctx = trace.StartSpan(ctx, "cloud.google.com/go/storage.ACL.List")
+	defer func() { trace.EndSpan(ctx, err) }()
+
+	if a.object != "" {
+		return a.objectList(ctx)
+	}
+	if a.isDefault {
+		return a.bucketDefaultList(ctx)
+	}
+	return a.bucketList(ctx)
+}
+
+func (a *ACLHandle) bucketDefaultList(ctx context.Context) ([]ACLRule, error) {
+	var acls *raw.ObjectAccessControls
+	var err error
+	err = runWithRetry(ctx, func() error {
+		req := a.c.raw.DefaultObjectAccessControls.List(a.bucket)
+		a.configureCall(ctx, req)
+		acls, err = req.Do()
+		return err
+	})
+	if err != nil {
+		return nil, err
+	}
+	return toObjectACLRules(acls.Items), nil
+}
+
+func (a *ACLHandle) bucketDefaultDelete(ctx context.Context, entity ACLEntity) error {
+	return runWithRetry(ctx, func() error {
+		req := a.c.raw.DefaultObjectAccessControls.Delete(a.bucket, string(entity))
+		a.configureCall(ctx, req)
+		return req.Do()
+	})
+}
+
+func (a *ACLHandle) bucketList(ctx context.Context) ([]ACLRule, error) {
+	var acls *raw.BucketAccessControls
+	var err error
+	err = runWithRetry(ctx, func() error {
+		req := a.c.raw.BucketAccessControls.List(a.bucket)
+		a.configureCall(ctx, req)
+		acls, err = req.Do()
+		return err
+	})
+	if err != nil {
+		return nil, err
+	}
+	return toBucketACLRules(acls.Items), nil
+}
+
+func (a *ACLHandle) bucketSet(ctx context.Context, entity ACLEntity, role ACLRole) error {
+	acl := &raw.BucketAccessControl{
+		Bucket: a.bucket,
+		Entity: string(entity),
+		Role:   string(role),
+	}
+	err := runWithRetry(ctx, func() error {
+		req := a.c.raw.BucketAccessControls.Update(a.bucket, string(entity), acl)
+		a.configureCall(ctx, req)
+		_, err := req.Do()
+		return err
+	})
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func (a *ACLHandle) bucketDelete(ctx context.Context, entity ACLEntity) error {
+	return runWithRetry(ctx, func() error {
+		req := a.c.raw.BucketAccessControls.Delete(a.bucket, string(entity))
+		a.configureCall(ctx, req)
+		return req.Do()
+	})
+}
+
+func (a *ACLHandle) objectList(ctx context.Context) ([]ACLRule, error) {
+	var acls *raw.ObjectAccessControls
+	var err error
+	err = runWithRetry(ctx, func() error {
+		req := a.c.raw.ObjectAccessControls.List(a.bucket, a.object)
+		a.configureCall(ctx, req)
+		acls, err = req.Do()
+		return err
+	})
+	if err != nil {
+		return nil, err
+	}
+	return toObjectACLRules(acls.Items), nil
+}
+
+func (a *ACLHandle) objectSet(ctx context.Context, entity ACLEntity, role ACLRole, isBucketDefault bool) error {
+	type setRequest interface {
+		Do(opts ...googleapi.CallOption) (*raw.ObjectAccessControl, error)
+		Header() http.Header
+	}
+
+	acl := &raw.ObjectAccessControl{
+		Bucket: a.bucket,
+		Entity: string(entity),
+		Role:   string(role),
+	}
+	var req setRequest
+	if isBucketDefault {
+		req = a.c.raw.DefaultObjectAccessControls.Update(a.bucket, string(entity), acl)
+	} else {
+		req = a.c.raw.ObjectAccessControls.Update(a.bucket, a.object, string(entity), acl)
+	}
+	a.configureCall(ctx, req)
+	return runWithRetry(ctx, func() error {
+		_, err := req.Do()
+		return err
+	})
+}
+
+func (a *ACLHandle) objectDelete(ctx context.Context, entity ACLEntity) error {
+	return runWithRetry(ctx, func() error {
+		req := a.c.raw.ObjectAccessControls.Delete(a.bucket, a.object, string(entity))
+		a.configureCall(ctx, req)
+		return req.Do()
+	})
+}
+
+func (a *ACLHandle) configureCall(ctx context.Context, call interface{ Header() http.Header }) {
+	vc := reflect.ValueOf(call)
+	vc.MethodByName("Context").Call([]reflect.Value{reflect.ValueOf(ctx)})
+	if a.userProject != "" {
+		vc.MethodByName("UserProject").Call([]reflect.Value{reflect.ValueOf(a.userProject)})
+	}
+	setClientHeader(call.Header())
+}
+
+func toObjectACLRules(items []*raw.ObjectAccessControl) []ACLRule {
+	var rs []ACLRule
+	for _, item := range items {
+		rs = append(rs, toObjectACLRule(item))
+	}
+	return rs
+}
+
+func toBucketACLRules(items []*raw.BucketAccessControl) []ACLRule {
+	var rs []ACLRule
+	for _, item := range items {
+		rs = append(rs, toBucketACLRule(item))
+	}
+	return rs
+}
+
+func toObjectACLRule(a *raw.ObjectAccessControl) ACLRule {
+	return ACLRule{
+		Entity:      ACLEntity(a.Entity),
+		EntityID:    a.EntityId,
+		Role:        ACLRole(a.Role),
+		Domain:      a.Domain,
+		Email:       a.Email,
+		ProjectTeam: toObjectProjectTeam(a.ProjectTeam),
+	}
+}
+
+func toBucketACLRule(a *raw.BucketAccessControl) ACLRule {
+	return ACLRule{
+		Entity:      ACLEntity(a.Entity),
+		EntityID:    a.EntityId,
+		Role:        ACLRole(a.Role),
+		Domain:      a.Domain,
+		Email:       a.Email,
+		ProjectTeam: toBucketProjectTeam(a.ProjectTeam),
+	}
+}
+
+func toRawObjectACL(rules []ACLRule) []*raw.ObjectAccessControl {
+	if len(rules) == 0 {
+		return nil
+	}
+	r := make([]*raw.ObjectAccessControl, 0, len(rules))
+	for _, rule := range rules {
+		r = append(r, rule.toRawObjectAccessControl("")) // bucket name unnecessary
+	}
+	return r
+}
+
+func toRawBucketACL(rules []ACLRule) []*raw.BucketAccessControl {
+	if len(rules) == 0 {
+		return nil
+	}
+	r := make([]*raw.BucketAccessControl, 0, len(rules))
+	for _, rule := range rules {
+		r = append(r, rule.toRawBucketAccessControl("")) // bucket name unnecessary
+	}
+	return r
+}
+
+func (r ACLRule) toRawBucketAccessControl(bucket string) *raw.BucketAccessControl {
+	return &raw.BucketAccessControl{
+		Bucket: bucket,
+		Entity: string(r.Entity),
+		Role:   string(r.Role),
+		// The other fields are not settable.
+	}
+}
+
+func (r ACLRule) toRawObjectAccessControl(bucket string) *raw.ObjectAccessControl {
+	return &raw.ObjectAccessControl{
+		Bucket: bucket,
+		Entity: string(r.Entity),
+		Role:   string(r.Role),
+		// The other fields are not settable.
+	}
+}
+
+func toBucketProjectTeam(p *raw.BucketAccessControlProjectTeam) *ProjectTeam {
+	if p == nil {
+		return nil
+	}
+	return &ProjectTeam{
+		ProjectNumber: p.ProjectNumber,
+		Team:          p.Team,
+	}
+}
+
+func toObjectProjectTeam(p *raw.ObjectAccessControlProjectTeam) *ProjectTeam {
+	if p == nil {
+		return nil
+	}
+	return &ProjectTeam{
+		ProjectNumber: p.ProjectNumber,
+		Team:          p.Team,
+	}
+}

vendor/cloud.google.com/go/storage/copy.go

@@ -0,0 +1,228 @@
+// Copyright 2016 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package storage
+
+import (
+	"context"
+	"errors"
+	"fmt"
+
+	"cloud.google.com/go/internal/trace"
+	raw "google.golang.org/api/storage/v1"
+)
+
+// CopierFrom creates a Copier that can copy src to dst.
+// You can immediately call Run on the returned Copier, or
+// you can configure it first.
+//
+// For Requester Pays buckets, the user project of dst is billed, unless it is empty,
+// in which case the user project of src is billed.
+func (dst *ObjectHandle) CopierFrom(src *ObjectHandle) *Copier {
+	return &Copier{dst: dst, src: src}
+}
+
+// A Copier copies a source object to a destination.
+type Copier struct {
+	// ObjectAttrs are optional attributes to set on the destination object.
+	// Any attributes must be initialized before any calls on the Copier. Nil
+	// or zero-valued attributes are ignored.
+	ObjectAttrs
+
+	// RewriteToken can be set before calling Run to resume a copy
+	// operation. After Run returns a non-nil error, RewriteToken will
+	// have been updated to contain the value needed to resume the copy.
+	RewriteToken string
+
+	// ProgressFunc can be used to monitor the progress of a multi-RPC copy
+	// operation. If ProgressFunc is not nil and copying requires multiple
+	// calls to the underlying service (see
+	// https://cloud.google.com/storage/docs/json_api/v1/objects/rewrite), then
+	// ProgressFunc will be invoked after each call with the number of bytes of
+	// content copied so far and the total size in bytes of the source object.
+	//
+	// ProgressFunc is intended to make upload progress available to the
+	// application. For example, the implementation of ProgressFunc may update
+	// a progress bar in the application's UI, or log the result of
+	// float64(copiedBytes)/float64(totalBytes).
+	//
+	// ProgressFunc should return quickly without blocking.
+	ProgressFunc func(copiedBytes, totalBytes uint64)
+
+	// The Cloud KMS key, in the form projects/P/locations/L/keyRings/R/cryptoKeys/K,
+	// that will be used to encrypt the object. Overrides the object's KMSKeyName, if
+	// any.
+	//
+	// Providing both a DestinationKMSKeyName and a customer-supplied encryption key
+	// (via ObjectHandle.Key) on the destination object will result in an error when
+	// Run is called.
+	DestinationKMSKeyName string
+
+	dst, src *ObjectHandle
+}
+
+// Run performs the copy.
+func (c *Copier) Run(ctx context.Context) (attrs *ObjectAttrs, err error) {
+	ctx = trace.StartSpan(ctx, "cloud.google.com/go/storage.Copier.Run")
+	defer func() { trace.EndSpan(ctx, err) }()
+
+	if err := c.src.validate(); err != nil {
+		return nil, err
+	}
+	if err := c.dst.validate(); err != nil {
+		return nil, err
+	}
+	if c.DestinationKMSKeyName != "" && c.dst.encryptionKey != nil {
+		return nil, errors.New("storage: cannot use DestinationKMSKeyName with a customer-supplied encryption key")
+	}
+	// Convert destination attributes to raw form, omitting the bucket.
+	// If the bucket is included but name or content-type aren't, the service
+	// returns a 400 with "Required" as the only message. Omitting the bucket
+	// does not cause any problems.
+	rawObject := c.ObjectAttrs.toRawObject("")
+	for {
+		res, err := c.callRewrite(ctx, rawObject)
+		if err != nil {
+			return nil, err
+		}
+		if c.ProgressFunc != nil {
+			c.ProgressFunc(uint64(res.TotalBytesRewritten), uint64(res.ObjectSize))
+		}
+		if res.Done { // Finished successfully.
+			return newObject(res.Resource), nil
+		}
+	}
+}
+
+func (c *Copier) callRewrite(ctx context.Context, rawObj *raw.Object) (*raw.RewriteResponse, error) {
+	call := c.dst.c.raw.Objects.Rewrite(c.src.bucket, c.src.object, c.dst.bucket, c.dst.object, rawObj)
+
+	call.Context(ctx).Projection("full")
+	if c.RewriteToken != "" {
+		call.RewriteToken(c.RewriteToken)
+	}
+	if c.DestinationKMSKeyName != "" {
+		call.DestinationKmsKeyName(c.DestinationKMSKeyName)
+	}
+	if c.PredefinedACL != "" {
+		call.DestinationPredefinedAcl(c.PredefinedACL)
+	}
+	if err := applyConds("Copy destination", c.dst.gen, c.dst.conds, call); err != nil {
+		return nil, err
+	}
+	if c.dst.userProject != "" {
+		call.UserProject(c.dst.userProject)
+	} else if c.src.userProject != "" {
+		call.UserProject(c.src.userProject)
+	}
+	if err := applySourceConds(c.src.gen, c.src.conds, call); err != nil {
+		return nil, err
+	}
+	if err := setEncryptionHeaders(call.Header(), c.dst.encryptionKey, false); err != nil {
+		return nil, err
+	}
+	if err := setEncryptionHeaders(call.Header(), c.src.encryptionKey, true); err != nil {
+		return nil, err
+	}
+	var res *raw.RewriteResponse
+	var err error
+	setClientHeader(call.Header())
+	err = runWithRetry(ctx, func() error { res, err = call.Do(); return err })
+	if err != nil {
+		return nil, err
+	}
+	c.RewriteToken = res.RewriteToken
+	return res, nil
+}
+
+// ComposerFrom creates a Composer that can compose srcs into dst.
+// You can immediately call Run on the returned Composer, or you can
+// configure it first.
+//
+// The encryption key for the destination object will be used to decrypt all
+// source objects and encrypt the destination object. It is an error
+// to specify an encryption key for any of the source objects.
+func (dst *ObjectHandle) ComposerFrom(srcs ...*ObjectHandle) *Composer {
+	return &Composer{dst: dst, srcs: srcs}
+}
+
+// A Composer composes source objects into a destination object.
+//
+// For Requester Pays buckets, the user project of dst is billed.
+type Composer struct {
+	// ObjectAttrs are optional attributes to set on the destination object.
+	// Any attributes must be initialized before any calls on the Composer. Nil
+	// or zero-valued attributes are ignored.
+	ObjectAttrs
+
+	dst  *ObjectHandle
+	srcs []*ObjectHandle
+}
+
+// Run performs the compose operation.
+func (c *Composer) Run(ctx context.Context) (attrs *ObjectAttrs, err error) {
+	ctx = trace.StartSpan(ctx, "cloud.google.com/go/storage.Composer.Run")
+	defer func() { trace.EndSpan(ctx, err) }()
+
+	if err := c.dst.validate(); err != nil {
+		return nil, err
+	}
+	if len(c.srcs) == 0 {
+		return nil, errors.New("storage: at least one source object must be specified")
+	}
+
+	req := &raw.ComposeRequest{}
+	// Compose requires a non-empty Destination, so we always set it,
+	// even if the caller-provided ObjectAttrs is the zero value.
+	req.Destination = c.ObjectAttrs.toRawObject(c.dst.bucket)
+	for _, src := range c.srcs {
+		if err := src.validate(); err != nil {
+			return nil, err
+		}
+		if src.bucket != c.dst.bucket {
+			return nil, fmt.Errorf("storage: all source objects must be in bucket %q, found %q", c.dst.bucket, src.bucket)
+		}
+		if src.encryptionKey != nil {
+			return nil, fmt.Errorf("storage: compose source %s.%s must not have encryption key", src.bucket, src.object)
+		}
+		srcObj := &raw.ComposeRequestSourceObjects{
+			Name: src.object,
+		}
+		if err := applyConds("ComposeFrom source", src.gen, src.conds, composeSourceObj{srcObj}); err != nil {
+			return nil, err
+		}
+		req.SourceObjects = append(req.SourceObjects, srcObj)
+	}
+
+	call := c.dst.c.raw.Objects.Compose(c.dst.bucket, c.dst.object, req).Context(ctx)
+	if err := applyConds("ComposeFrom destination", c.dst.gen, c.dst.conds, call); err != nil {
+		return nil, err
+	}
+	if c.dst.userProject != "" {
+		call.UserProject(c.dst.userProject)
+	}
+	if c.PredefinedACL != "" {
+		call.DestinationPredefinedAcl(c.PredefinedACL)
+	}
+	if err := setEncryptionHeaders(call.Header(), c.dst.encryptionKey, false); err != nil {
+		return nil, err
+	}
+	var obj *raw.Object
+	setClientHeader(call.Header())
+	err = runWithRetry(ctx, func() error { obj, err = call.Do(); return err })
+	if err != nil {
+		return nil, err
+	}
+	return newObject(obj), nil
+}

vendor/cloud.google.com/go/storage/doc.go

@@ -0,0 +1,176 @@
+// Copyright 2016 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/*
+Package storage provides an easy way to work with Google Cloud Storage.
+Google Cloud Storage stores data in named objects, which are grouped into buckets.
+
+More information about Google Cloud Storage is available at
+https://cloud.google.com/storage/docs.
+
+See https://godoc.org/cloud.google.com/go for authentication, timeouts,
+connection pooling and similar aspects of this package.
+
+All of the methods of this package use exponential backoff to retry calls that fail
+with certain errors, as described in
+https://cloud.google.com/storage/docs/exponential-backoff. Retrying continues
+indefinitely unless the controlling context is canceled or the client is closed. See
+context.WithTimeout and context.WithCancel.
+
+
+Creating a Client
+
+To start working with this package, create a client:
+
+    ctx := context.Background()
+    client, err := storage.NewClient(ctx)
+    if err != nil {
+        // TODO: Handle error.
+    }
+
+The client will use your default application credentials.
+
+If you only wish to access public data, you can create
+an unauthenticated client with
+
+    client, err := storage.NewClient(ctx, option.WithoutAuthentication())
+
+Buckets
+
+A Google Cloud Storage bucket is a collection of objects. To work with a
+bucket, make a bucket handle:
+
+    bkt := client.Bucket(bucketName)
+
+A handle is a reference to a bucket. You can have a handle even if the
+bucket doesn't exist yet. To create a bucket in Google Cloud Storage,
+call Create on the handle:
+
+    if err := bkt.Create(ctx, projectID, nil); err != nil {
+        // TODO: Handle error.
+    }
+
+Note that although buckets are associated with projects, bucket names are
+global across all projects.
+
+Each bucket has associated metadata, represented in this package by
+BucketAttrs. The third argument to BucketHandle.Create allows you to set
+the initial BucketAttrs of a bucket. To retrieve a bucket's attributes, use
+Attrs:
+
+    attrs, err := bkt.Attrs(ctx)
+    if err != nil {
+        // TODO: Handle error.
+    }
+    fmt.Printf("bucket %s, created at %s, is located in %s with storage class %s\n",
+        attrs.Name, attrs.Created, attrs.Location, attrs.StorageClass)
+
+Objects
+
+An object holds arbitrary data as a sequence of bytes, like a file. You
+refer to objects using a handle, just as with buckets, but unlike buckets
+you don't explicitly create an object. Instead, the first time you write
+to an object it will be created. You can use the standard Go io.Reader
+and io.Writer interfaces to read and write object data:
+
+    obj := bkt.Object("data")
+    // Write something to obj.
+    // w implements io.Writer.
+    w := obj.NewWriter(ctx)
+    // Write some text to obj. This will either create the object or overwrite whatever is there already.
+    if _, err := fmt.Fprintf(w, "This object contains text.\n"); err != nil {
+        // TODO: Handle error.
+    }
+    // Close, just like writing a file.
+    if err := w.Close(); err != nil {
+        // TODO: Handle error.
+    }
+
+    // Read it back.
+    r, err := obj.NewReader(ctx)
+    if err != nil {
+        // TODO: Handle error.
+    }
+    defer r.Close()
+    if _, err := io.Copy(os.Stdout, r); err != nil {
+        // TODO: Handle error.
+    }
+    // Prints "This object contains text."
+
+Objects also have attributes, which you can fetch with Attrs:
+
+    objAttrs, err := obj.Attrs(ctx)
+    if err != nil {
+        // TODO: Handle error.
+    }
+    fmt.Printf("object %s has size %d and can be read using %s\n",
+        objAttrs.Name, objAttrs.Size, objAttrs.MediaLink)
+
+ACLs
+
+Both objects and buckets have ACLs (Access Control Lists). An ACL is a list of
+ACLRules, each of which specifies the role of a user, group or project. ACLs
+are suitable for fine-grained control, but you may prefer using IAM to control
+access at the project level (see
+https://cloud.google.com/storage/docs/access-control/iam).
+
+To list the ACLs of a bucket or object, obtain an ACLHandle and call its List method:
+
+    acls, err := obj.ACL().List(ctx)
+    if err != nil {
+        // TODO: Handle error.
+    }
+    for _, rule := range acls {
+        fmt.Printf("%s has role %s\n", rule.Entity, rule.Role)
+    }
+
+You can also set and delete ACLs.
+
+Conditions
+
+Every object has a generation and a metageneration. The generation changes
+whenever the content changes, and the metageneration changes whenever the
+metadata changes. Conditions let you check these values before an operation;
+the operation only executes if the conditions match. You can use conditions to
+prevent race conditions in read-modify-write operations.
+
+For example, say you've read an object's metadata into objAttrs. Now
+you want to write to that object, but only if its contents haven't changed
+since you read it. Here is how to express that:
+
+    w = obj.If(storage.Conditions{GenerationMatch: objAttrs.Generation}).NewWriter(ctx)
+    // Proceed with writing as above.
+
+Signed URLs
+
+You can obtain a URL that lets anyone read or write an object for a limited time.
+You don't need to create a client to do this. See the documentation of
+SignedURL for details.
+
+    url, err := storage.SignedURL(bucketName, "shared-object", opts)
+    if err != nil {
+        // TODO: Handle error.
+    }
+    fmt.Println(url)
+
+Errors
+
+Errors returned by this client are often of the type [`googleapi.Error`](https://godoc.org/google.golang.org/api/googleapi#Error).
+These errors can be introspected for more information by type asserting to the richer `googleapi.Error` type. For example:
+
+	if e, ok := err.(*googleapi.Error); ok {
+		  if e.Code == 409 { ... }
+	}
+*/
+package storage // import "cloud.google.com/go/storage"

vendor/cloud.google.com/go/storage/go110.go

@@ -0,0 +1,32 @@
+// Copyright 2017 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build go1.10
+
+package storage
+
+import "google.golang.org/api/googleapi"
+
+func shouldRetry(err error) bool {
+	switch e := err.(type) {
+	case *googleapi.Error:
+		// Retry on 429 and 5xx, according to
+		// https://cloud.google.com/storage/docs/exponential-backoff.
+		return e.Code == 429 || (e.Code >= 500 && e.Code < 600)
+	case interface{ Temporary() bool }:
+		return e.Temporary()
+	default:
+		return false
+	}
+}

vendor/cloud.google.com/go/storage/iam.go

@@ -0,0 +1,130 @@
+// Copyright 2017 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package storage
+
+import (
+	"context"
+
+	"cloud.google.com/go/iam"
+	"cloud.google.com/go/internal/trace"
+	raw "google.golang.org/api/storage/v1"
+	iampb "google.golang.org/genproto/googleapis/iam/v1"
+)
+
+// IAM provides access to IAM access control for the bucket.
+func (b *BucketHandle) IAM() *iam.Handle {
+	return iam.InternalNewHandleClient(&iamClient{
+		raw:         b.c.raw,
+		userProject: b.userProject,
+	}, b.name)
+}
+
+// iamClient implements the iam.client interface.
+type iamClient struct {
+	raw         *raw.Service
+	userProject string
+}
+
+func (c *iamClient) Get(ctx context.Context, resource string) (p *iampb.Policy, err error) {
+	ctx = trace.StartSpan(ctx, "cloud.google.com/go/storage.IAM.Get")
+	defer func() { trace.EndSpan(ctx, err) }()
+
+	call := c.raw.Buckets.GetIamPolicy(resource)
+	setClientHeader(call.Header())
+	if c.userProject != "" {
+		call.UserProject(c.userProject)
+	}
+	var rp *raw.Policy
+	err = runWithRetry(ctx, func() error {
+		rp, err = call.Context(ctx).Do()
+		return err
+	})
+	if err != nil {
+		return nil, err
+	}
+	return iamFromStoragePolicy(rp), nil
+}
+
+func (c *iamClient) Set(ctx context.Context, resource string, p *iampb.Policy) (err error) {
+	ctx = trace.StartSpan(ctx, "cloud.google.com/go/storage.IAM.Set")
+	defer func() { trace.EndSpan(ctx, err) }()
+
+	rp := iamToStoragePolicy(p)
+	call := c.raw.Buckets.SetIamPolicy(resource, rp)
+	setClientHeader(call.Header())
+	if c.userProject != "" {
+		call.UserProject(c.userProject)
+	}
+	return runWithRetry(ctx, func() error {
+		_, err := call.Context(ctx).Do()
+		return err
+	})
+}
+
+func (c *iamClient) Test(ctx context.Context, resource string, perms []string) (permissions []string, err error) {
+	ctx = trace.StartSpan(ctx, "cloud.google.com/go/storage.IAM.Test")
+	defer func() { trace.EndSpan(ctx, err) }()
+
+	call := c.raw.Buckets.TestIamPermissions(resource, perms)
+	setClientHeader(call.Header())
+	if c.userProject != "" {
+		call.UserProject(c.userProject)
+	}
+	var res *raw.TestIamPermissionsResponse
+	err = runWithRetry(ctx, func() error {
+		res, err = call.Context(ctx).Do()
+		return err
+	})
+	if err != nil {
+		return nil, err
+	}
+	return res.Permissions, nil
+}
+
+func iamToStoragePolicy(ip *iampb.Policy) *raw.Policy {
+	return &raw.Policy{
+		Bindings: iamToStorageBindings(ip.Bindings),
+		Etag:     string(ip.Etag),
+	}
+}
+
+func iamToStorageBindings(ibs []*iampb.Binding) []*raw.PolicyBindings {
+	var rbs []*raw.PolicyBindings
+	for _, ib := range ibs {
+		rbs = append(rbs, &raw.PolicyBindings{
+			Role:    ib.Role,
+			Members: ib.Members,
+		})
+	}
+	return rbs
+}
+
+func iamFromStoragePolicy(rp *raw.Policy) *iampb.Policy {
+	return &iampb.Policy{
+		Bindings: iamFromStorageBindings(rp.Bindings),
+		Etag:     []byte(rp.Etag),
+	}
+}
+
+func iamFromStorageBindings(rbs []*raw.PolicyBindings) []*iampb.Binding {
+	var ibs []*iampb.Binding
+	for _, rb := range rbs {
+		ibs = append(ibs, &iampb.Binding{
+			Role:    rb.Role,
+			Members: rb.Members,
+		})
+	}
+	return ibs
+}

vendor/cloud.google.com/go/storage/invoke.go

@@ -0,0 +1,37 @@
+// Copyright 2014 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package storage
+
+import (
+	"context"
+
+	"cloud.google.com/go/internal"
+	gax "github.com/googleapis/gax-go/v2"
+)
+
+// runWithRetry calls the function until it returns nil or a non-retryable error, or
+// the context is done.
+func runWithRetry(ctx context.Context, call func() error) error {
+	return internal.Retry(ctx, gax.Backoff{}, func() (stop bool, err error) {
+		err = call()
+		if err == nil {
+			return true, nil
+		}
+		if shouldRetry(err) {
+			return false, nil
+		}
+		return true, err
+	})
+}

vendor/cloud.google.com/go/storage/not_go110.go

@@ -0,0 +1,42 @@
+// Copyright 2017 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build !go1.10
+
+package storage
+
+import (
+	"net/url"
+	"strings"
+
+	"google.golang.org/api/googleapi"
+)
+
+func shouldRetry(err error) bool {
+	switch e := err.(type) {
+	case *googleapi.Error:
+		// Retry on 429 and 5xx, according to
+		// https://cloud.google.com/storage/docs/exponential-backoff.
+		return e.Code == 429 || (e.Code >= 500 && e.Code < 600)
+	case *url.Error:
+		// Retry on REFUSED_STREAM.
+		// Unfortunately the error type is unexported, so we resort to string
+		// matching.
+		return strings.Contains(e.Error(), "REFUSED_STREAM")
+	case interface{ Temporary() bool }:
+		return e.Temporary()
+	default:
+		return false
+	}
+}

vendor/cloud.google.com/go/storage/notifications.go

@@ -0,0 +1,188 @@
+// Copyright 2017 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package storage
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"regexp"
+
+	"cloud.google.com/go/internal/trace"
+	raw "google.golang.org/api/storage/v1"
+)
+
+// A Notification describes how to send Cloud PubSub messages when certain
+// events occur in a bucket.
+type Notification struct {
+	//The ID of the notification.
+	ID string
+
+	// The ID of the topic to which this subscription publishes.
+	TopicID string
+
+	// The ID of the project to which the topic belongs.
+	TopicProjectID string
+
+	// Only send notifications about listed event types. If empty, send notifications
+	// for all event types.
+	// See https://cloud.google.com/storage/docs/pubsub-notifications#events.
+	EventTypes []string
+
+	// If present, only apply this notification configuration to object names that
+	// begin with this prefix.
+	ObjectNamePrefix string
+
+	// An optional list of additional attributes to attach to each Cloud PubSub
+	// message published for this notification subscription.
+	CustomAttributes map[string]string
+
+	// The contents of the message payload.
+	// See https://cloud.google.com/storage/docs/pubsub-notifications#payload.
+	PayloadFormat string
+}
+
+// Values for Notification.PayloadFormat.
+const (
+	// Send no payload with notification messages.
+	NoPayload = "NONE"
+
+	// Send object metadata as JSON with notification messages.
+	JSONPayload = "JSON_API_V1"
+)
+
+// Values for Notification.EventTypes.
+const (
+	// Event that occurs when an object is successfully created.
+	ObjectFinalizeEvent = "OBJECT_FINALIZE"
+
+	// Event that occurs when the metadata of an existing object changes.
+	ObjectMetadataUpdateEvent = "OBJECT_METADATA_UPDATE"
+
+	// Event that occurs when an object is permanently deleted.
+	ObjectDeleteEvent = "OBJECT_DELETE"
+
+	// Event that occurs when the live version of an object becomes an
+	// archived version.
+	ObjectArchiveEvent = "OBJECT_ARCHIVE"
+)
+
+func toNotification(rn *raw.Notification) *Notification {
+	n := &Notification{
+		ID:               rn.Id,
+		EventTypes:       rn.EventTypes,
+		ObjectNamePrefix: rn.ObjectNamePrefix,
+		CustomAttributes: rn.CustomAttributes,
+		PayloadFormat:    rn.PayloadFormat,
+	}
+	n.TopicProjectID, n.TopicID = parseNotificationTopic(rn.Topic)
+	return n
+}
+
+var topicRE = regexp.MustCompile("^//pubsub.googleapis.com/projects/([^/]+)/topics/([^/]+)")
+
+// parseNotificationTopic extracts the project and topic IDs from from the full
+// resource name returned by the service. If the name is malformed, it returns
+// "?" for both IDs.
+func parseNotificationTopic(nt string) (projectID, topicID string) {
+	matches := topicRE.FindStringSubmatch(nt)
+	if matches == nil {
+		return "?", "?"
+	}
+	return matches[1], matches[2]
+}
+
+func toRawNotification(n *Notification) *raw.Notification {
+	return &raw.Notification{
+		Id: n.ID,
+		Topic: fmt.Sprintf("//pubsub.googleapis.com/projects/%s/topics/%s",
+			n.TopicProjectID, n.TopicID),
+		EventTypes:       n.EventTypes,
+		ObjectNamePrefix: n.ObjectNamePrefix,
+		CustomAttributes: n.CustomAttributes,
+		PayloadFormat:    string(n.PayloadFormat),
+	}
+}
+
+// AddNotification adds a notification to b. You must set n's TopicProjectID, TopicID
+// and PayloadFormat, and must not set its ID. The other fields are all optional. The
+// returned Notification's ID can be used to refer to it.
+func (b *BucketHandle) AddNotification(ctx context.Context, n *Notification) (ret *Notification, err error) {
+	ctx = trace.StartSpan(ctx, "cloud.google.com/go/storage.Bucket.AddNotification")
+	defer func() { trace.EndSpan(ctx, err) }()
+
+	if n.ID != "" {
+		return nil, errors.New("storage: AddNotification: ID must not be set")
+	}
+	if n.TopicProjectID == "" {
+		return nil, errors.New("storage: AddNotification: missing TopicProjectID")
+	}
+	if n.TopicID == "" {
+		return nil, errors.New("storage: AddNotification: missing TopicID")
+	}
+	call := b.c.raw.Notifications.Insert(b.name, toRawNotification(n))
+	setClientHeader(call.Header())
+	if b.userProject != "" {
+		call.UserProject(b.userProject)
+	}
+	rn, err := call.Context(ctx).Do()
+	if err != nil {
+		return nil, err
+	}
+	return toNotification(rn), nil
+}
+
+// Notifications returns all the Notifications configured for this bucket, as a map
+// indexed by notification ID.
+func (b *BucketHandle) Notifications(ctx context.Context) (n map[string]*Notification, err error) {
+	ctx = trace.StartSpan(ctx, "cloud.google.com/go/storage.Bucket.Notifications")
+	defer func() { trace.EndSpan(ctx, err) }()
+
+	call := b.c.raw.Notifications.List(b.name)
+	setClientHeader(call.Header())
+	if b.userProject != "" {
+		call.UserProject(b.userProject)
+	}
+	var res *raw.Notifications
+	err = runWithRetry(ctx, func() error {
+		res, err = call.Context(ctx).Do()
+		return err
+	})
+	if err != nil {
+		return nil, err
+	}
+	return notificationsToMap(res.Items), nil
+}
+
+func notificationsToMap(rns []*raw.Notification) map[string]*Notification {
+	m := map[string]*Notification{}
+	for _, rn := range rns {
+		m[rn.Id] = toNotification(rn)
+	}
+	return m
+}
+
+// DeleteNotification deletes the notification with the given ID.
+func (b *BucketHandle) DeleteNotification(ctx context.Context, id string) (err error) {
+	ctx = trace.StartSpan(ctx, "cloud.google.com/go/storage.Bucket.DeleteNotification")
+	defer func() { trace.EndSpan(ctx, err) }()
+
+	call := b.c.raw.Notifications.Delete(b.name, id)
+	setClientHeader(call.Header())
+	if b.userProject != "" {
+		call.UserProject(b.userProject)
+	}
+	return call.Context(ctx).Do()
+}

vendor/cloud.google.com/go/storage/reader.go

@@ -0,0 +1,385 @@
+// Copyright 2016 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package storage
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"hash/crc32"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"net/url"
+	"reflect"
+	"strconv"
+	"strings"
+	"time"
+
+	"cloud.google.com/go/internal/trace"
+	"google.golang.org/api/googleapi"
+)
+
+var crc32cTable = crc32.MakeTable(crc32.Castagnoli)
+
+// ReaderObjectAttrs are attributes about the object being read. These are populated
+// during the New call. This struct only holds a subset of object attributes: to
+// get the full set of attributes, use ObjectHandle.Attrs.
+//
+// Each field is read-only.
+type ReaderObjectAttrs struct {
+	// Size is the length of the object's content.
+	Size int64
+
+	// ContentType is the MIME type of the object's content.
+	ContentType string
+
+	// ContentEncoding is the encoding of the object's content.
+	ContentEncoding string
+
+	// CacheControl specifies whether and for how long browser and Internet
+	// caches are allowed to cache your objects.
+	CacheControl string
+
+	// LastModified is the time that the object was last modified.
+	LastModified time.Time
+
+	// Generation is the generation number of the object's content.
+	Generation int64
+
+	// Metageneration is the version of the metadata for this object at
+	// this generation. This field is used for preconditions and for
+	// detecting changes in metadata. A metageneration number is only
+	// meaningful in the context of a particular generation of a
+	// particular object.
+	Metageneration int64
+}
+
+// NewReader creates a new Reader to read the contents of the
+// object.
+// ErrObjectNotExist will be returned if the object is not found.
+//
+// The caller must call Close on the returned Reader when done reading.
+func (o *ObjectHandle) NewReader(ctx context.Context) (*Reader, error) {
+	return o.NewRangeReader(ctx, 0, -1)
+}
+
+// NewRangeReader reads part of an object, reading at most length bytes
+// starting at the given offset. If length is negative, the object is read
+// until the end.
+func (o *ObjectHandle) NewRangeReader(ctx context.Context, offset, length int64) (r *Reader, err error) {
+	ctx = trace.StartSpan(ctx, "cloud.google.com/go/storage.Object.NewRangeReader")
+	defer func() { trace.EndSpan(ctx, err) }()
+
+	if err := o.validate(); err != nil {
+		return nil, err
+	}
+	if offset < 0 {
+		return nil, fmt.Errorf("storage: invalid offset %d < 0", offset)
+	}
+	if o.conds != nil {
+		if err := o.conds.validate("NewRangeReader"); err != nil {
+			return nil, err
+		}
+	}
+	u := &url.URL{
+		Scheme: "https",
+		Host:   "storage.googleapis.com",
+		Path:   fmt.Sprintf("/%s/%s", o.bucket, o.object),
+	}
+	verb := "GET"
+	if length == 0 {
+		verb = "HEAD"
+	}
+	req, err := http.NewRequest(verb, u.String(), nil)
+	if err != nil {
+		return nil, err
+	}
+	req = req.WithContext(ctx)
+	if o.userProject != "" {
+		req.Header.Set("X-Goog-User-Project", o.userProject)
+	}
+	if o.readCompressed {
+		req.Header.Set("Accept-Encoding", "gzip")
+	}
+	if err := setEncryptionHeaders(req.Header, o.encryptionKey, false); err != nil {
+		return nil, err
+	}
+
+	gen := o.gen
+
+	// Define a function that initiates a Read with offset and length, assuming we
+	// have already read seen bytes.
+	reopen := func(seen int64) (*http.Response, error) {
+		start := offset + seen
+		if length < 0 && start > 0 {
+			req.Header.Set("Range", fmt.Sprintf("bytes=%d-", start))
+		} else if length > 0 {
+			// The end character isn't affected by how many bytes we've seen.
+			req.Header.Set("Range", fmt.Sprintf("bytes=%d-%d", start, offset+length-1))
+		}
+		// We wait to assign conditions here because the generation number can change in between reopen() runs.
+		req.URL.RawQuery = conditionsQuery(gen, o.conds)
+		var res *http.Response
+		err = runWithRetry(ctx, func() error {
+			res, err = o.c.hc.Do(req)
+			if err != nil {
+				return err
+			}
+			if res.StatusCode == http.StatusNotFound {
+				res.Body.Close()
+				return ErrObjectNotExist
+			}
+			if res.StatusCode < 200 || res.StatusCode > 299 {
+				body, _ := ioutil.ReadAll(res.Body)
+				res.Body.Close()
+				return &googleapi.Error{
+					Code:   res.StatusCode,
+					Header: res.Header,
+					Body:   string(body),
+				}
+			}
+			if start > 0 && length != 0 && res.StatusCode != http.StatusPartialContent {
+				res.Body.Close()
+				return errors.New("storage: partial request not satisfied")
+			}
+			// If a generation hasn't been specified, and this is the first response we get, let's record the
+			// generation. In future requests we'll use this generation as a precondition to avoid data races.
+			if gen < 0 && res.Header.Get("X-Goog-Generation") != "" {
+				gen64, err := strconv.ParseInt(res.Header.Get("X-Goog-Generation"), 10, 64)
+				if err != nil {
+					return err
+				}
+				gen = gen64
+			}
+			return nil
+		})
+		if err != nil {
+			return nil, err
+		}
+		return res, nil
+	}
+
+	res, err := reopen(0)
+	if err != nil {
+		return nil, err
+	}
+	var (
+		size     int64 // total size of object, even if a range was requested.
+		checkCRC bool
+		crc      uint32
+	)
+	if res.StatusCode == http.StatusPartialContent {
+		cr := strings.TrimSpace(res.Header.Get("Content-Range"))
+		if !strings.HasPrefix(cr, "bytes ") || !strings.Contains(cr, "/") {
+
+			return nil, fmt.Errorf("storage: invalid Content-Range %q", cr)
+		}
+		size, err = strconv.ParseInt(cr[strings.LastIndex(cr, "/")+1:], 10, 64)
+		if err != nil {
+			return nil, fmt.Errorf("storage: invalid Content-Range %q", cr)
+		}
+	} else {
+		size = res.ContentLength
+		// Check the CRC iff all of the following hold:
+		// - We asked for content (length != 0).
+		// - We got all the content (status != PartialContent).
+		// - The server sent a CRC header.
+		// - The Go http stack did not uncompress the file.
+		// - We were not served compressed data that was uncompressed on download.
+		// The problem with the last two cases is that the CRC will not match -- GCS
+		// computes it on the compressed contents, but we compute it on the
+		// uncompressed contents.
+		if length != 0 && !res.Uncompressed && !uncompressedByServer(res) {
+			crc, checkCRC = parseCRC32c(res)
+		}
+	}
+
+	remain := res.ContentLength
+	body := res.Body
+	if length == 0 {
+		remain = 0
+		body.Close()
+		body = emptyBody
+	}
+	var metaGen int64
+	if res.Header.Get("X-Goog-Generation") != "" {
+		metaGen, err = strconv.ParseInt(res.Header.Get("X-Goog-Metageneration"), 10, 64)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	var lm time.Time
+	if res.Header.Get("Last-Modified") != "" {
+		lm, err = http.ParseTime(res.Header.Get("Last-Modified"))
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	attrs := ReaderObjectAttrs{
+		Size:            size,
+		ContentType:     res.Header.Get("Content-Type"),
+		ContentEncoding: res.Header.Get("Content-Encoding"),
+		CacheControl:    res.Header.Get("Cache-Control"),
+		LastModified:    lm,
+		Generation:      gen,
+		Metageneration:  metaGen,
+	}
+	return &Reader{
+		Attrs:    attrs,
+		body:     body,
+		size:     size,
+		remain:   remain,
+		wantCRC:  crc,
+		checkCRC: checkCRC,
+		reopen:   reopen,
+	}, nil
+}
+
+func uncompressedByServer(res *http.Response) bool {
+	// If the data is stored as gzip but is not encoded as gzip, then it
+	// was uncompressed by the server.
+	return res.Header.Get("X-Goog-Stored-Content-Encoding") == "gzip" &&
+		res.Header.Get("Content-Encoding") != "gzip"
+}
+
+func parseCRC32c(res *http.Response) (uint32, bool) {
+	const prefix = "crc32c="
+	for _, spec := range res.Header["X-Goog-Hash"] {
+		if strings.HasPrefix(spec, prefix) {
+			c, err := decodeUint32(spec[len(prefix):])
+			if err == nil {
+				return c, true
+			}
+		}
+	}
+	return 0, false
+}
+
+var emptyBody = ioutil.NopCloser(strings.NewReader(""))
+
+// Reader reads a Cloud Storage object.
+// It implements io.Reader.
+//
+// Typically, a Reader computes the CRC of the downloaded content and compares it to
+// the stored CRC, returning an error from Read if there is a mismatch. This integrity check
+// is skipped if transcoding occurs. See https://cloud.google.com/storage/docs/transcoding.
+type Reader struct {
+	Attrs              ReaderObjectAttrs
+	body               io.ReadCloser
+	seen, remain, size int64
+	checkCRC           bool   // should we check the CRC?
+	wantCRC            uint32 // the CRC32c value the server sent in the header
+	gotCRC             uint32 // running crc
+	reopen             func(seen int64) (*http.Response, error)
+}
+
+// Close closes the Reader. It must be called when done reading.
+func (r *Reader) Close() error {
+	return r.body.Close()
+}
+
+func (r *Reader) Read(p []byte) (int, error) {
+	n, err := r.readWithRetry(p)
+	if r.remain != -1 {
+		r.remain -= int64(n)
+	}
+	if r.checkCRC {
+		r.gotCRC = crc32.Update(r.gotCRC, crc32cTable, p[:n])
+		// Check CRC here. It would be natural to check it in Close, but
+		// everybody defers Close on the assumption that it doesn't return
+		// anything worth looking at.
+		if err == io.EOF {
+			if r.gotCRC != r.wantCRC {
+				return n, fmt.Errorf("storage: bad CRC on read: got %d, want %d",
+					r.gotCRC, r.wantCRC)
+			}
+		}
+	}
+	return n, err
+}
+
+func (r *Reader) readWithRetry(p []byte) (int, error) {
+	n := 0
+	for len(p[n:]) > 0 {
+		m, err := r.body.Read(p[n:])
+		n += m
+		r.seen += int64(m)
+		if !shouldRetryRead(err) {
+			return n, err
+		}
+		// Read failed, but we will try again. Send a ranged read request that takes
+		// into account the number of bytes we've already seen.
+		res, err := r.reopen(r.seen)
+		if err != nil {
+			// reopen already retries
+			return n, err
+		}
+		r.body.Close()
+		r.body = res.Body
+	}
+	return n, nil
+}
+
+func shouldRetryRead(err error) bool {
+	if err == nil {
+		return false
+	}
+	return strings.HasSuffix(err.Error(), "INTERNAL_ERROR") && strings.Contains(reflect.TypeOf(err).String(), "http2")
+}
+
+// Size returns the size of the object in bytes.
+// The returned value is always the same and is not affected by
+// calls to Read or Close.
+//
+// Deprecated: use Reader.Attrs.Size.
+func (r *Reader) Size() int64 {
+	return r.Attrs.Size
+}
+
+// Remain returns the number of bytes left to read, or -1 if unknown.
+func (r *Reader) Remain() int64 {
+	return r.remain
+}
+
+// ContentType returns the content type of the object.
+//
+// Deprecated: use Reader.Attrs.ContentType.
+func (r *Reader) ContentType() string {
+	return r.Attrs.ContentType
+}
+
+// ContentEncoding returns the content encoding of the object.
+//
+// Deprecated: use Reader.Attrs.ContentEncoding.
+func (r *Reader) ContentEncoding() string {
+	return r.Attrs.ContentEncoding
+}
+
+// CacheControl returns the cache control of the object.
+//
+// Deprecated: use Reader.Attrs.CacheControl.
+func (r *Reader) CacheControl() string {
+	return r.Attrs.CacheControl
+}
+
+// LastModified returns the value of the Last-Modified header.
+//
+// Deprecated: use Reader.Attrs.LastModified.
+func (r *Reader) LastModified() (time.Time, error) {
+	return r.Attrs.LastModified, nil
+}

vendor/cloud.google.com/go/storage/writer.go

@@ -0,0 +1,261 @@
+// Copyright 2014 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package storage
+
+import (
+	"context"
+	"encoding/base64"
+	"errors"
+	"fmt"
+	"io"
+	"sync"
+	"unicode/utf8"
+
+	"google.golang.org/api/googleapi"
+	raw "google.golang.org/api/storage/v1"
+)
+
+// A Writer writes a Cloud Storage object.
+type Writer struct {
+	// ObjectAttrs are optional attributes to set on the object. Any attributes
+	// must be initialized before the first Write call. Nil or zero-valued
+	// attributes are ignored.
+	ObjectAttrs
+
+	// SendCRC specifies whether to transmit a CRC32C field. It should be set
+	// to true in addition to setting the Writer's CRC32C field, because zero
+	// is a valid CRC and normally a zero would not be transmitted.
+	// If a CRC32C is sent, and the data written does not match the checksum,
+	// the write will be rejected.
+	SendCRC32C bool
+
+	// ChunkSize controls the maximum number of bytes of the object that the
+	// Writer will attempt to send to the server in a single request. Objects
+	// smaller than the size will be sent in a single request, while larger
+	// objects will be split over multiple requests. The size will be rounded up
+	// to the nearest multiple of 256K. If zero, chunking will be disabled and
+	// the object will be uploaded in a single request.
+	//
+	// ChunkSize will default to a reasonable value. If you perform many concurrent
+	// writes of small objects, you may wish set ChunkSize to a value that matches
+	// your objects' sizes to avoid consuming large amounts of memory.
+	//
+	// ChunkSize must be set before the first Write call.
+	ChunkSize int
+
+	// ProgressFunc can be used to monitor the progress of a large write.
+	// operation. If ProgressFunc is not nil and writing requires multiple
+	// calls to the underlying service (see
+	// https://cloud.google.com/storage/docs/json_api/v1/how-tos/resumable-upload),
+	// then ProgressFunc will be invoked after each call with the number of bytes of
+	// content copied so far.
+	//
+	// ProgressFunc should return quickly without blocking.
+	ProgressFunc func(int64)
+
+	ctx context.Context
+	o   *ObjectHandle
+
+	opened bool
+	pw     *io.PipeWriter
+
+	donec chan struct{} // closed after err and obj are set.
+	obj   *ObjectAttrs
+
+	mu  sync.Mutex
+	err error
+}
+
+func (w *Writer) open() error {
+	attrs := w.ObjectAttrs
+	// Check the developer didn't change the object Name (this is unfortunate, but
+	// we don't want to store an object under the wrong name).
+	if attrs.Name != w.o.object {
+		return fmt.Errorf("storage: Writer.Name %q does not match object name %q", attrs.Name, w.o.object)
+	}
+	if !utf8.ValidString(attrs.Name) {
+		return fmt.Errorf("storage: object name %q is not valid UTF-8", attrs.Name)
+	}
+	if attrs.KMSKeyName != "" && w.o.encryptionKey != nil {
+		return errors.New("storage: cannot use KMSKeyName with a customer-supplied encryption key")
+	}
+	pr, pw := io.Pipe()
+	w.pw = pw
+	w.opened = true
+
+	go w.monitorCancel()
+
+	if w.ChunkSize < 0 {
+		return errors.New("storage: Writer.ChunkSize must be non-negative")
+	}
+	mediaOpts := []googleapi.MediaOption{
+		googleapi.ChunkSize(w.ChunkSize),
+	}
+	if c := attrs.ContentType; c != "" {
+		mediaOpts = append(mediaOpts, googleapi.ContentType(c))
+	}
+
+	go func() {
+		defer close(w.donec)
+
+		rawObj := attrs.toRawObject(w.o.bucket)
+		if w.SendCRC32C {
+			rawObj.Crc32c = encodeUint32(attrs.CRC32C)
+		}
+		if w.MD5 != nil {
+			rawObj.Md5Hash = base64.StdEncoding.EncodeToString(w.MD5)
+		}
+		call := w.o.c.raw.Objects.Insert(w.o.bucket, rawObj).
+			Media(pr, mediaOpts...).
+			Projection("full").
+			Context(w.ctx)
+		if w.ProgressFunc != nil {
+			call.ProgressUpdater(func(n, _ int64) { w.ProgressFunc(n) })
+		}
+		if attrs.KMSKeyName != "" {
+			call.KmsKeyName(attrs.KMSKeyName)
+		}
+		if attrs.PredefinedACL != "" {
+			call.PredefinedAcl(attrs.PredefinedACL)
+		}
+		if err := setEncryptionHeaders(call.Header(), w.o.encryptionKey, false); err != nil {
+			w.mu.Lock()
+			w.err = err
+			w.mu.Unlock()
+			pr.CloseWithError(err)
+			return
+		}
+		var resp *raw.Object
+		err := applyConds("NewWriter", w.o.gen, w.o.conds, call)
+		if err == nil {
+			if w.o.userProject != "" {
+				call.UserProject(w.o.userProject)
+			}
+			setClientHeader(call.Header())
+			// If the chunk size is zero, then no chunking is done on the Reader,
+			// which means we cannot retry: the first call will read the data, and if
+			// it fails, there is no way to re-read.
+			if w.ChunkSize == 0 {
+				resp, err = call.Do()
+			} else {
+				// We will only retry here if the initial POST, which obtains a URI for
+				// the resumable upload, fails with a retryable error. The upload itself
+				// has its own retry logic.
+				err = runWithRetry(w.ctx, func() error {
+					var err2 error
+					resp, err2 = call.Do()
+					return err2
+				})
+			}
+		}
+		if err != nil {
+			w.mu.Lock()
+			w.err = err
+			w.mu.Unlock()
+			pr.CloseWithError(err)
+			return
+		}
+		w.obj = newObject(resp)
+	}()
+	return nil
+}
+
+// Write appends to w. It implements the io.Writer interface.
+//
+// Since writes happen asynchronously, Write may return a nil
+// error even though the write failed (or will fail). Always
+// use the error returned from Writer.Close to determine if
+// the upload was successful.
+func (w *Writer) Write(p []byte) (n int, err error) {
+	w.mu.Lock()
+	werr := w.err
+	w.mu.Unlock()
+	if werr != nil {
+		return 0, werr
+	}
+	if !w.opened {
+		if err := w.open(); err != nil {
+			return 0, err
+		}
+	}
+	n, err = w.pw.Write(p)
+	if err != nil {
+		w.mu.Lock()
+		werr := w.err
+		w.mu.Unlock()
+		// Preserve existing functionality that when context is canceled, Write will return
+		// context.Canceled instead of "io: read/write on closed pipe". This hides the
+		// pipe implementation detail from users and makes Write seem as though it's an RPC.
+		if werr == context.Canceled || werr == context.DeadlineExceeded {
+			return n, werr
+		}
+	}
+	return n, err
+}
+
+// Close completes the write operation and flushes any buffered data.
+// If Close doesn't return an error, metadata about the written object
+// can be retrieved by calling Attrs.
+func (w *Writer) Close() error {
+	if !w.opened {
+		if err := w.open(); err != nil {
+			return err
+		}
+	}
+
+	// Closing either the read or write causes the entire pipe to close.
+	if err := w.pw.Close(); err != nil {
+		return err
+	}
+
+	<-w.donec
+	w.mu.Lock()
+	defer w.mu.Unlock()
+	return w.err
+}
+
+// monitorCancel is intended to be used as a background goroutine. It monitors the
+// the context, and when it observes that the context has been canceled, it manually
+// closes things that do not take a context.
+func (w *Writer) monitorCancel() {
+	select {
+	case <-w.ctx.Done():
+		w.mu.Lock()
+		werr := w.ctx.Err()
+		w.err = werr
+		w.mu.Unlock()
+
+		// Closing either the read or write causes the entire pipe to close.
+		w.CloseWithError(werr)
+	case <-w.donec:
+	}
+}
+
+// CloseWithError aborts the write operation with the provided error.
+// CloseWithError always returns nil.
+//
+// Deprecated: cancel the context passed to NewWriter instead.
+func (w *Writer) CloseWithError(err error) error {
+	if !w.opened {
+		return nil
+	}
+	return w.pw.CloseWithError(err)
+}
+
+// Attrs returns metadata about a successfully-written object.
+// It's only valid to call it after Close returns nil.
+func (w *Writer) Attrs() *ObjectAttrs {
+	return w.obj
+}