使用NodeJS從IBM Bluemix Object Storage下載文件

Question

使用NodeJS腳本從IBM Bluemix Object Storage下載文件時出現問題，問題是需要很長時間才能從存儲中下載文件，100K文件需要大約21秒，大約8秒鐘等待第一個塊並休息讀取所有塊

我正在使用該服務來存儲圖像並使用NodeJS腳本從存儲中讀取這些圖像，並通過HTML下載圖像img標籤，所以我在這裏做錯了什麼？

的代碼的NodeJS：

app.get("/ostore/image/:filename", function(request, response) { 
    response.set('Content-Type', 'image/jpg'); 
    response.set('cache-control', 'max-age=604800'); 
    response.set('Last-Modified', 'Sat, 05 Dec 2015 03:17:48 GMT'); 
    var credentials = app.appEnv.services['Object-Storage'][0].credentials 
    var pkgcloud = require("pkgcloud"); 
    var client = pkgcloud.storage.createClient({ 
     provider: 'openstack', 
     username: credentials.userId, 
     password: credentials.password, 
     authUrl: credentials.auth_url, 
     tenantId: credentials.projectId, 
     region: credentials.region, 
     version: "2" 
    }); 
    client.download({ 
     container: app.storageContainer, 
     remote: request.params.filename, 
     stream: response 
    }, function() { 
     response.end('done'); 
    }); 
}); 

Answer 1

嘗試是這樣的：

routes.js

var vcap_os = require(__dirname + '/../utils/vcap')('Object-Storage'), 
    os = require(__dirname + '/../modules/object-storage'); 

module.exports = function(app) { 
    var router = app.loopback.Router(); 

    // proxy for object storage service 
    router.get('/api/Products/image/:container/:file', function(req, res) { 
     os(vcap_os.credentials).download(req.params.container, req.params.file, function(download) { 
      download.pipe(res); 
     }); 
    }); 

    app.use(router); 
} 

模塊/對象storage.js

var pkgcloud = require('pkgcloud'); 

module.exports = function(creds) { 
    var config = { 
     provider: 'openstack', 
     useServiceCatalog: true, 
     useInternal: false, 
     keystoneAuthVersion: 'v3', 
     authUrl: creds.auth_url, 
     tenantId: creds.projectId, 
     domainId: creds.domainId, 
     username: creds.username, 
     password: creds.password, 
     region: creds.region 
    }; 

    return { 
     download: function(container, file, cbk) { 
      var client = pkgcloud.storage.createClient(config); 
      client.auth(function (error) { 
       if(error) { 
        console.error("Authorization error for storage client (pkgcloud): ", error); 
       } 
       else { 
        var request = client.download({ 
         container: container, 
         remote: file 
        }); 

        cbk(request); 
       } 
      }); 
     } 
    }; 
}; 

Answer 2

使用joe的答案，並且很少修改，服務現在工作正常，我必須更改庫pkgcloud，因爲它導致bluemix身份驗證問題，我切換到包裝程序包pkgcloud-bluemix-objectstorage，my代碼看起來像這樣：

app.get('/ostore/image/:filename', (request, response) => { 
    const credentials = app.appEnv.services['Object-Storage'][0].credentials; 
    const config = {}; 
    config.provider = 'openstack'; 
    config.authUrl = 'https://identity.open.softlayer.com/'; 
    config.region = credentials.region; 
    config.useServiceCatalog = true; 
    config.useInternal = true; 
    config.tenantId = credentials.projectId; 
    config.userId = credentials.userId; 
    config.username = credentials.username; 
    config.password = credentials.password; 
    config.auth = { 
     forceUri: 'https://identity.open.softlayer.com/v3/auth/tokens', 
     interfaceName: 'public', 
     identity: { 
      methods: [ 
       'password' 
      ], 
      password: { 
       user: { 
        id: credentials.userId, 
        password: credentials.password 
       } 
      } 
     }, 
     scope: { 
      project: { 
       id: credentials.projectId 
      } 
     } 
    }; 

    const client = pkgcloud.storage.createClient(config); 
    client.auth(error => { 
     if (error) { 
      console.error('Authorization error for storage client (pkgcloud): ', error); 
     } else { 
      const download = client.download({ 
       container: app.storageContainer, 
       remote: request.params.filename 
      }); 
      download.on('response', res => { 
       delete res.headers['content-type']; 
       delete res.headers['last-modified']; 
       res.headers['Last-Modified'] = 'Sat, 05 Dec 2015 03:17:48 GMT'; 
       res.headers['Cache-Control'] = 'public, max-age=2592000'; 
       res.headers['Expires'] = new Date(Date.now() + 2592000000).toUTCString(); 
       res.headers['Content-Type'] = 'image/jpg'; 
      }).pipe(response); 
     } 
    }); 
});