cloudcmd/lib/server/main.js

(function(){
    'strict mode';
    
    /* Global var accessible from any loaded module */
    global.cloudcmd     = {};
    
    var DIR, LIBDIR, SRVDIR, JSONDIR,
        Util,
        
        SLASH,
        ISWIN32,
        ext,
        path, fs, zlib, url,
        
        OK, FILE_NOT_FOUND;
    
    /* Consts */
    
    exports.OK          = OK                = 200;
    exports.FILE_NOT_FOUND                  = 404;
    exports.REQUEST                         = 'request';
    exports.RESPONSE                        = 'response';
    
    /* Native Modules*/
    exports.crypto                          = require('crypto'),
    exports.child_process                   = require('child_process'),
    exports.fs          = fs                = require('fs'),
    exports.http                            = require('http'),
    exports.https                           = require('https'),
    exports.path        = path              = require('path'),
    exports.url         = url               = require('url'),
    exports.querystring                     = require('querystring'),
    
    /* Constants */
    /* current dir + 2 levels up */
    exports.WIN32       = ISWIN32           = isWin32();
    exports.SLASH       = SLASH             = ISWIN32 ? '\\' : '/',
    
    exports.SRVDIR      = SRVDIR            = __dirname + SLASH,
    exports.LIBDIR      = LIBDIR            = path.normalize(SRVDIR + '../'),
    exports.DIR         = DIR               = path.normalize(LIBDIR + '../'),
    exports.HTMLDIR                         = DIR + 'html' + SLASH,
    exports.JSONDIR     = JSONDIR           = DIR + 'json' + SLASH,
    
    /* Functions */
    exports.require                         = mrequire,
    exports.librequire                      = librequire,
    exports.srvrequire                      = srvrequire,
    exports.rootrequire                     = rootrequire,
    exports.generateHeaders                 = generateHeaders,
    exports.getQuery                        = getQuery,
    exports.sendFile                        = sendFile,
    
    /* compitability with old versions of node */
    exports.fs.exists                       = exports.fs.exists || exports.path.exists;
    //exports.fs.watch                        = isWin32 ? fs.watch : linuxWatch;
     
    
    /* Needed Modules */
    exports.util        = Util              = require(LIBDIR + 'util'),
    
    exports.zlib        = zlib              = mrequire('zlib'),
    
    /* Main Information */
    exports.modules                         = jsonrequire('modules');
    exports.ext         = ext               = jsonrequire('ext');
    exports.mainpackage                     = rootrequire('package');
    /* base configuration */
    exports.config                          = {
        server  : true,
        socket  : true,
        port    : 80
    },
    
    
    /* 
     * Any of loaded below modules could work with global var so
     * it should be initialized first. Becouse of almost any of
     * moudles do not depends on each other all needed information
     * for all modules is initialized hear.
     */
    global.cloudcmd.main                    = exports;
    
    exports.VOLUMES                         = getVolumes(),
    
    /* Additional Modules */
    exports.socket                          = srvrequire('socket'),
    exports.auth                            = srvrequire('auth').auth,
    exports.appcache                        = srvrequire('appcache'),
    exports.cache                           = srvrequire('cache').Cache,
    exports.cloudfunc                       = librequire('cloudfunc'),
    exports.rest                            = srvrequire('rest').api,
    exports.update                          = srvrequire('update'),
    exports.ischanged                       = srvrequire('ischanged');
    exports.commander                       = srvrequire('commander');
    exports.minify                          = srvrequire('minify').Minify;
    /*
     * second initializing after all modules load, so global var is
     * totally filled of all information that should know all modules
     */
    global.cloudcmd.main            = exports;
    /**
     * function do safe require of needed module
     * @param {Strin} pSrc
     */
    function mrequire(pSrc){
        var lModule,
        lError = Util.tryCatchLog(function(){
            lModule = require(pSrc);
        });
        
        if(lError)
            console.log(lError);
        
        return lModule;
    }
    
    function rootrequire(pSrc){ return mrequire(DIR + pSrc); }
    
    function librequire(pSrc){ return mrequire(LIBDIR + pSrc); }
    
    function srvrequire(pSrc){ return mrequire(SRVDIR + pSrc); }
    
    function jsonrequire(pSrc){ return mrequire(JSONDIR + pSrc);}
    
    /**
     * function check is current platform is win32
     */
    function isWin32(){ return process.platform === 'win32'; }
    
    /**
     * get volumes if win32 or get nothing if nix
     */
    function getVolumes(){
        var lRet = ISWIN32 ? [] : '/';
                
        if(ISWIN32)
            srvrequire('win').getVolumes(function(pVolumes){
                console.log(pVolumes);
                exports.VOLUMES = pVolumes;
            });

        return lRet;
    }
    
    /**
     * Функция создаёт заголовки файлов
     * в зависимости от расширения файла
     * перед отправкой их клиенту
     * @param pName - имя файла
     * @param pGzip - данные сжаты gzip'ом
     */
    function generateHeaders(pName, pGzip, pQuery){
        var lRet,
            lType               = '',
            lContentEncoding    = '',
            lCacheControl       = 0,
            
            lExt                = Util.getExtension(pName);
        
        if( Util.strCmp(lExt, '.appcache') )
            lCacheControl = 1;
        
        lType = ext[lExt] || 'text/plain';
        
        /* if type of file any, but img - 
         * then we shoud specify charset 
         */
        if( !Util.isContainStr(lType, 'img') )
            lContentEncoding = '; charset=UTF-8';
        
        if(Util.strCmp(pQuery, 'download') )
            lType = 'application/octet-stream';
        
        
        if(!lCacheControl)
            lCacheControl = 31337 * 21;
        
        lRet = {
            'Content-Type': lType + lContentEncoding,
            'cache-control': 'max-age=' + lCacheControl,
            'last-modified': new Date().toString(),
            /* https://developers.google.com/speed/docs/best-practices
            /caching?hl=ru#LeverageProxyCaching */
            'Vary': 'Accept-Encoding'
        };
        
        if(pGzip)
            lRet['content-encoding'] = 'gzip';
            
        return lRet;
    }
    
    /**
     * send file to client thru pipe
     * and gzip it if client support
     * 
     * @param pName - имя файла
     * @param pGzip - данные сжаты gzip'ом
     */
    function sendFile(pParams){
        var lRet,
            lName, lReq, lRes, lQuery, lGziped;
        
        if(pParams){
            lName   = pParams.name,
            lReq    = pParams.request,
            lRes    = pParams.response;
            lGziped = pParams.gziped;
            lQuery  = getQuery(lReq);
        }
        
        if(lName && lRes && lReq){
            var lEnc    = lReq.headers['accept-encoding'] || '',
                lGzip   = lEnc.match(/\bgzip\b/),
                
                lReadStream = fs.createReadStream(lName, {
                    'bufferSize': 4 * 1024
                });
            
            lReadStream.on('error', function(pError){
                lRes.writeHead(FILE_NOT_FOUND, 'OK');
                lRes.end(String(pError));
            });
            
            lRes.writeHead(OK, generateHeaders(lName, lGzip, lQuery ) );
            
            if (lGzip && !lGziped)
                lReadStream = lReadStream.pipe( zlib.createGzip() );
            
            lReadStream.pipe(lRes);
            
            lRet = true;
        }
        
        return lRet;
    }
    
    function getQuery(pReq){
        var lQuery, lParsedUrl;
        
        if(pReq){
            lParsedUrl  = url.parse(pReq.url);
            lQuery      = lParsedUrl.query;
        }
        
        return lQuery;
    }
    
    
    function linuxWatch(pFile, pCallBack){
        fs.watchFile(pFile, function(pCurr, pPrev){
            if(pCurr.mtime !== pPrev.mtime)
                Util.exec(pCallBack);
        });
    }
    
})();