refactor(env): add getEnvOptional for non-required environment variables

- Add getEnvOptional() method for accessing optional environment variables
- Separate REQUIRED_ENV_KEYS from OPTIONAL_ENV_KEYS in load-env.js
- Update UnsplashService to use getEnvOptional() instead of getEnv()
- ENV object now only contains actual values, not 'undefined' strings
- Cleaner separation between required and optional configuration

src/app/core/unsplash/unsplash.service.ts

@@ -2,7 +2,7 @@ import { Injectable } from '@angular/core';
 import { HttpClient } from '@angular/common/http';
 import { Observable, of } from 'rxjs';
 import { catchError } from 'rxjs/operators';
-import { getEnv } from '../../util/env';
+import { getEnvOptional } from '../../util/env';
 
 export interface UnsplashPhoto {
   id: string;
@@ -42,12 +42,12 @@ export class UnsplashService {
   private readonly API_URL = 'https://api.unsplash.com';
   // Register your app at https://unsplash.com/developers for a free Access Key (50 req/hour)
   // The Access Key is used with "Client-ID" prefix in the Authorization header
-  private readonly ACCESS_KEY = getEnv('UNSPLASH_KEY');
+  private readonly ACCESS_KEY = getEnvOptional('UNSPLASH_KEY');
 
   constructor(private _http: HttpClient) {}
 
   isAvailable(): boolean {
-    return !!this.ACCESS_KEY && this.ACCESS_KEY !== 'undefined';
+    return !!this.ACCESS_KEY;
   }
 
   searchPhotos(query: string, page = 1): Observable<UnsplashSearchResponse> {

src/app/util/env.ts

@@ -15,6 +15,16 @@ export const getEnv = (key: keyof typeof ENV): string | undefined => {
   return ENV[key] || undefined;
 };
 
+/**
+ * Get an optional environment variable that may not be in the required list.
+ * Use this for environment variables that are truly optional and may not be defined
+ * in the REQUIRED_ENV_KEYS list in load-env.js.
+ * Returns undefined if the variable is not set.
+ */
+export const getEnvOptional = (key: string): string | undefined => {
+  return (ENV as any)[key] || undefined;
+};
+
 /**
  * Get an environment variable as a number.
  * Returns undefined if the value is not a valid number.

tools/load-env.js

@@ -4,19 +4,29 @@ const fs = require('fs');
 const path = require('path');
 const dotenv = require('dotenv');
 
+// Define keys that should always be included in types for backwards compatibility
+// These are checked with getEnv() which requires strict typing
 const REQUIRED_ENV_KEYS = [
-  'UNSPLASH_KEY',
-  'UNSPLASH_CLIENT_ID',
-  // 'GOOGLE_DRIVE_TOKEN',
-  // 'DROPBOX_API_KEY',
-  // 'WEBDAV_URL',
-  // 'WEBDAV_USERNAME',
-  // 'WEBDAV_PASSWORD',
+  // Currently empty - add keys here that should always be in the type definition
 ];
 
-// Start with system environment variables for required keys
+// Define optional keys that might be provided
+// These can be accessed with getEnvOptional() without strict typing
+const OPTIONAL_ENV_KEYS = [
+  'UNSPLASH_KEY',
+  'UNSPLASH_CLIENT_ID',
+  'GOOGLE_DRIVE_TOKEN',
+  'DROPBOX_API_KEY',
+  'WEBDAV_URL',
+  'WEBDAV_USERNAME',
+  'WEBDAV_PASSWORD',
+];
+
+const ALL_KEYS = [...REQUIRED_ENV_KEYS, ...OPTIONAL_ENV_KEYS];
+
+// Start with system environment variables
 const env = {};
-REQUIRED_ENV_KEYS.forEach((key) => {
+ALL_KEYS.forEach((key) => {
   if (process.env[key]) {
     env[key] = process.env[key];
   }
@@ -26,32 +36,32 @@ REQUIRED_ENV_KEYS.forEach((key) => {
 const envPath = path.join(process.cwd(), '.env');
 const envConfig = dotenv.config({ path: envPath });
 if (envConfig.parsed) {
+  // Add all values from .env file, not just the predefined keys
   Object.assign(env, envConfig.parsed);
 }
 
 // Log what we found
-const foundKeys = Object.keys(env).filter((key) => REQUIRED_ENV_KEYS.includes(key));
+const foundKeys = Object.keys(env);
 if (foundKeys.length > 0) {
-  console.log(
-    `✅ Found ${foundKeys.length} environment variable(s): ${foundKeys.join(', ')}`,
-  );
+  console.log(`✅ Found ${foundKeys.length} environment variable(s)`);
 } else {
-  console.warn(
-    '⚠️  No environment variables found, generating env.generated.ts with undefined values',
-  );
+  console.warn('⚠️  No environment variables found');
 }
 
-// Create ENV object with all expected keys (undefined if not set)
-const envEntries = REQUIRED_ENV_KEYS.map((key) => {
-  const value = env[key];
-  if (value !== undefined) {
-    // Escape quotes in values
-    const escapedValue = value.replace(/'/g, "\\'");
-    return `  ${key}: '${escapedValue}',`;
-  } else {
-    return `  ${key}: undefined,`;
-  }
-});
+// Create ENV object with all found keys plus required keys (undefined if not set)
+const allEnvKeys = new Set([...REQUIRED_ENV_KEYS, ...Object.keys(env)]);
+const envEntries = Array.from(allEnvKeys)
+  .sort()
+  .map((key) => {
+    const value = env[key];
+    if (value !== undefined) {
+      // Escape quotes in values
+      const escapedValue = value.replace(/'/g, "\\'");
+      return `  ${key}: '${escapedValue}',`;
+    } else if (REQUIRED_ENV_KEYS.includes(key)) {
+      throw new Error(`Required env key ${key} not found`);
+    }
+  });
 
 // Generate TypeScript content
 const tsContent = `// This file is auto-generated by tools/load-env.js