Microsoft Azure Storage SDK for Node.js

This project provides a Node.js package that makes it easy to consume and manage Microsoft Azure Storage Services.

If you are looking for documentation for the Azure SDK for Node.js, see http://dl.windowsazure.com/nodedocs/index.html or visit https://github.com/Azure/azure-sdk-for-node. While the Azure SDK for Node.js provides support for working with Azure Storage, you should consider using the Azure Storage SDK as it supports features not available in the Azure SDK for Node.js

Features

• Tables
  • Create/Delete Tables
  • Query/Create/Read/Update/Delete Entities
• Blobs
  • Create/Read/Update/Delete Blobs
• Files
  • Create/Update/Delete Directories
  • Create/Read/Update/Delete Files
• Queues
  • Create/Delete Queues
  • Insert/Peek Queue Messages
  • Advanced Queue Operations

Getting Started

Install

npm install azure-storage

Usage

var azure = require('azure-storage');

When using the Storage SDK, you must provide connection information for the storage account to use. This can be provided using:

• Environment variables - AZURE_STORAGE_ACCOUNT and AZURE_STORAGE_ACCESS_KEY, or AZURE_STORAGE_CONNECTION_STRING.

• Constructors - For example, var tableSvc = azure.createTableService(accountName, accountKey);

Table Storage

To ensure a table exists, call createTableIfNotExists:

var azure = require('azure-storage');
var tableService = azure.createTableService();
tableService.createTableIfNotExists('mytable', function(error, result, response){
  if(!error){
    // result contains true if created; false if already exists
  }
});

A new entity can be added by calling insertEntity:

var azure = require('azure-storage');
var tableService = azure.createTableService(),
var entGen = azure.TableUtilities.entityGenerator;
var entity = { 	PartitionKey: entGen.String('part2'),
				RowKey: entGen.String('row1'),
				boolValueTrue: entGen.Boolean(true),
				boolValueFalse: entGen.Boolean(false),
				intValue: entGen.Int32(42),
				dateValue: entGen.DateTime(new Date(Date.UTC(2011, 10, 25))),
				complexDateValue: entGen.DateTime(new Date(Date.UTC(2013, 02, 16, 01, 46, 20)))
			 };
tableService.insertEntity('mytable',entity, function (error, result, response) {
  if(!error){
    // result contains the ETag for the new entity
  }
});

Instead of creating entities manually, you can use entityGenerator:

var azure = require('azure-storage');
var entGen = azure.TableUtilities.entityGenerator;
var task = {
  PartitionKey: entGen.String('hometasks'),
  RowKey: entGen.String('1'),
  description: entGen.String('take out the trash'),
  dueDate: entGen.DateTime(new Date(Date.UTC(2015, 6, 20))),
};

The method retrieveEntity can then be used to fetch the entity that was just inserted:

var azure = require('azure-storage');
var tableService = azure.createTableService();
tableService.retrieveEntity('mytable', 'part2', 'row1', function(error, result, response){
  if(!error){
    // result contains the entity
  }
});

Use TableQuery to build complex queries:

var azure = require('azure-storage');
var tableService = azure.createTableService();
var query = azure.TableQuery()
		    .top(5)
		    .where('PartitionKey eq ?', 'part2');

tableSvc.queryEntities('mytable', query, null, function(error, result, response) {
  if(!error) {
    // result.entries contains entities matching the query
  }
});

Blob Storage

The createContainerIfNotExists method can be used to create a container in which to store a blob:

var azure = require('azure-storage');
var blobService = azure.createBlobService();
blobService.createContainerIfNotExists('taskcontainer', {publicAccessLevel : 'blob'}, function(error, result, response){
    if(!error){
        // if result = true, container was created.
        // if result = false, container already existed.
    }
});

To upload a file (assuming it is called task1-upload.txt and it is placed in the same folder as the script below), the method createBlockBlobFromLocalFile can be used.

var azure = require('azure-storage');
var blobService = azure.createBlobService();

blobService.createBlockBlobFromLocalFile('mycontainer', 'taskblob', 'task1-upload.txt', function(error, result, response){
  if(!error){
    // file uploaded
  }
});

For page blobs, use createPageBlobFromLocalFile. There are other methods for uploading blobs also, such as createBlockBlobFromText or createPageBlobFromStream.

There are also several ways to download block and page blobs. For example, getBlockBlobToStream downloads the blob to a stream:

var blobService = azure.createBlobService();
var fs = require('fs');
blobService.getBlockBlobToStream('mycontainer', 'taskblob', fs.createWriteStream('output.txt'), function(error, result, response){
  if(!error) {
    // blob retrieved
  }
});

To create a Shared Access Signature (SAS), use the generateSharedAccessSignature method. Additionally you can use the date helper functions to easily create a SAS that expires at some point relative to the current time.

var azure = require('azure-storage');
var blobService = azure.createBlobService();


var startDate = new Date();
var expiryDate = new Date(startDate);
expiryDate.setMinutes(startDate.getMinutes() + 100);
startDate.setMinutes(startDate.getMinutes() - 100);

var sharedAccessPolicy = {
    AccessPolicy: {
      Permissions: azure.BlobUtilities.SharedAccessPermissions.READ,
      Start: startDate,
      Expiry: expiryDate
  },
};

var token = blobService.generateSharedAccessSignature(containerName, blobName, sharedAccessPolicy);
var sasUrl = blobService.getUrl(containerName, blobName, token);

Queue Storage

The createQueueIfNotExists method can be used to ensure a queue exists:

var azure = require('azure-storage');
var queueService = azure.createQueueService();
queueService.createQueueIfNotExists('taskqueue', function(error){
    if(!error){
        // Queue exists
    }
});

The createMessage method can then be called to insert the message into the queue:

var queueService = azure.createQueueService();
queueService.createMessage('taskqueue', 'Hello world!', function(error){
    if(!error){
        // Message inserted
    }
});

It is then possible to call the getMessage method, process the message and then call deleteMessage inside the callback. This two-step process ensures messages don't get lost when they are removed from the queue.

var queueService = azure.createQueueService(),
    queueName = 'taskqueue';
queueService.getMessages(queueName, function(error, serverMessages){
    if(!error){
        // Process the message in less than 30 seconds, the message
        // text is available in serverMessages[0].messagetext

        queueService.deleteMessage(queueName, serverMessages[0].messageid, serverMessages[0].popreceipt, function(error){
            if(!error){
                // Message deleted
            }
        });
    }
});

File Storage

The createShareIfNotExists method can be used to create a share in which to store a file or a directory of files:

var azure = require('azure-storage');
var fileService = azure.createFileService();
fileService.createShareIfNotExists('taskshare', function(error, result, response){
    if(!error){
        // if result = true, share was created.
        // if result = false, share already existed.
    }
});

To create a directory, the method createDirectoryIfNotExists can be used.

var azure = require('azure-storage');
var fileService = azure.createFileService();

fileService.createDirectoryIfNotExists('taskshare', 'taskdirectory', function(error, result, response){
    if(!error){
        // if result = true, share was created.
        // if result = false, share already existed.
    }
});

To upload a file (assuming it is called task1-upload.txt and it is placed in the same folder as the script below), the method createFileFromLocalFile can be used.

var azure = require('azure-storage');
var fileService = azure.createFileService();

fileService.createFileFromLocalFile('taskshare', 'taskdirectory', 'taskfile', 'task1-upload.txt', function(error, result, response){
  if(!error){
    // file uploaded
  }
});

There are other methods for uploading files also, such as createFileFromText or createFileFromStream.

There are also several ways to download files. For example, getFileToStream downloads the file to a stream:

var fileService = azure.createFileService();
var fs = require('fs');
fileService.getFileToStream('taskshare', 'taskdirectory', 'taskfile', fs.createWriteStream('output.txt'), function(error, result, response){
  if(!error) {
    // file retrieved
  }
});

Code Samples

How-Tos focused around accomplishing specific tasks are available on the Microsoft Azure Node.js Developer Center.

• How to use the Blob Service from Node.js

• How to use the Table Service from Node.js

• How to use the Queue Service from Node.js

Running Tests

In order to run the tests, the following environment variables need to be set up:

AZURE_STORAGE_CONNECTION_STRING="valid storage connection string"

or

AZURE_STORAGE_ACCOUNT="valid storage account name"

AZURE_STORAGE_ACCESS_KEY="valid storage account key"

In order to be able to use a proxy like fiddler, an additional environment variable should be set up:

HTTP_PROXY=http://127.0.0.1:8888

The tests can then be run from the module's root directory using:

npm test

Need Help?

Be sure to check out the Microsoft Azure Developer Forums on MSDN if you have trouble with the provided code or use StackOverflow.

Learn More

• Microsoft Azure Node.js Developer Center
• [Azure Storage Team Blog] (http://blogs.msdn.com/b/windowsazurestorage/)

Contribute

We gladly accept community contributions.

• Issues: Please report bugs using the Issues section of GitHub
• Forums: Interact with the development teams on StackOverflow or the Microsoft Azure Forums
• Source Code Contributions: If you would like to become an active contributor to this project please follow the instructions provided in Microsoft Azure Projects Contribution Guidelines.

For general suggestions about Microsoft Azure please use our UserVoice forum.