azure

Windows Azure SDK for Node.js

This project provides a set of Node.js packages that make it easy to access the Windows Azure storage and queue services. For documentation on how to host Node.js applications on Windows Azure, please see the Windows Azure Node.js Developer Center.

Features

• Tables
  • create and delete tables
  • create, query, insert, update, merge, and delete entities
  • Blobs
    • create, list, and delete containers, work with container metadata and permissions, list blobs in container
    • create block and page blobs (from a stream, a file, or a string), work with blob blocks and pages, delete blobs
    • work with blob properties, metadata, leases, snapshot a blob
    • Queues
      • create, list, and delete queues, and work with queue metadata
      • create, get, peek, update, delete messages

      Getting Started

      Download Source Code

      To get the source code of the SDK via git just type:
      

      git clone https://github.com/WindowsAzure/azure-sdk-for-node.git
      cd ./azure-sdk-for-node

      Download Package

      Alternatively, to get the source code via the Node Package Manager (npm), type
      

      npm install azure

      You can use these packages against the cloud Windows Azure Services, or against the local Storage Emulator.

      1. To use the cloud services, you need to first create an account with Windows Azure. You need to set the AZURE_STORAGE_ACCOUNT and the AZURE_STORAGE_ACCESS_KEY environment variables to the storage account name and primary access key you obtain from the Azure Portal.
      2. To use the Storage Emulator, make sure the latest version of the Windows Azure SDK is installed on the machine, and set the EMULATED environment variable to any value ("true", "1", etc.)

      Usage

      Table Storage

      To ensure a table exists, call createTableIfNotExists:

      var tableService = azure.createTableService();
      tableService.createTableIfNotExists('tasktable', function(error){
          if(!error){
              // Table exists
          }
      });
      

      A new entity can be added by calling insertEntity:

      var tableService = azure.createTableService(),
          task1 = {
              PartitionKey : 'tasksSeattle',
              RowKey: '1',
              Description: 'Take out the trash',
              DueDate: new Date(2011, 12, 14, 12) 
          };
      tableService.insertEntity('tasktable', task1, function(error){ 
          if(!error){
              // Entity inserted
          }
      });
      

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

      var tableService = azure.createTableService();
      tableService.queryEntity('tasktable', 'tasksSeattle', '1', function(error, serverEntity){
          if(!error){
              // Entity available in serverEntity variable
          }
      });
      

      Blob Storage

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

      var blobService = azure.createBlobService();
      blobService.createContainerIfNotExists('taskcontainer', {publicAccessLevel : 'blob'}, function(error){
          if(!error){
              // Container exists and is public
          }
      });
      

      To upload a file (assuming it is called task1-upload.txt, it contains the exact text "hello world" (no quotation marks), and it is placed in the same folder as the script below), the method createBlockBlobFromStream can be used:

      var blobService = azure.createBlobService();
      blobService.createBlockBlobFromStream('taskcontainer', 'task1', fs.createReadStream('task1-upload.txt'), 11, function(error){
          if(!error){
              // Blob uploaded
          }
      });
      

      To download the blob and write it to the file system, the getBlobToStream method can be used:

      var blobService = azure.createBlobService();
      blobService.getBlobToStream('taskcontainer', 'task1', fs.createWriteStream('task1-download.txt'), function(error, serverBlob){
          if(!error){
              // Blob available in serverBlob.blob variable
          }
      });
      

      Storage Queues

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

      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
              }
          });
      }
      
      });
      

      ServiceBus Queues

      ServiceBus Queues are an alternative to Storage Queues that might be useful in scenarios where more advanced messaging features are needed (larger message sizes, message ordering, single-operaiton destructive reads, scheduled delivery) using push-style delivery (using long polling).

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

      var serviceBusService = azure.createServiceBusService();
      serviceBusService.createQueueIfNotExists('taskqueue', function(error){
          if(!error){
              // Queue exists
          }
      });
      

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

      var serviceBusService = azure.createServiceBusService();
      serviceBusService.sendQueueMessage('taskqueue', 'Hello world!', function(
          if(!error){
              // Message sent
           }
      });
      

      It is then possible to call the receiveQueueMessage method to dequeue the message.

      var serviceBusService = azure.createServiceBusService();
      serviceBusService.receiveQueueMessage('taskqueue', function(error, serverMessage){
          if(!error){
              // Process the message
          }
      });
      

      ServiceBus Topics

      ServiceBus topics are an abstraction on top of ServiceBus Queues that make pub/sub scenarios easy to implement.

      The createTopicIfNotExists method can be used to create a server-side topic:

      var serviceBusService = azure.createServiceBusService();
      serviceBusService.createTopicIfNotExists('taskdiscussion', function(error){
          if(!error){
              // Topic exists
          }
      });
      

      The sendTopicMessage method can be used to send a message to a topic:

      var serviceBusService = azure.createServiceBusService();
      serviceBusService.sendTopicMessage('taskdiscussion', 'Hello world!', function(error){
          if(!error){
              // Message sent
          }
      });
      

      A client can then create a subscription and start consuming messages by calling the createSubscription method followed by the receiveSubscriptionMessage method. Please note that any messages sent before the subscription is created will not be received.

      var serviceBusService = azure.createServiceBusService(),
          topic = 'taskdiscussion',
          subscription = 'client1';
      serviceBusService.createSubscription(topic, subscription, function(error1){
      if(!error1){
      // Subscription created
          serviceBusService.receiveSubscriptionMessage(topic, subscription, function(error2, serverMessage){
              if(!error2){
                  // Process message
              }
          });
       }
      
      });
      

      For more examples please see the Windows Azure Node.js Developer Center.

      Need Help?

      Be sure to check out the Windows Azure Developer Forums on Stack Overflow if you have trouble with the provided code.

      Contribute Code or Provide Feedback

      If you would like to become an active contributor to this project please follow the instructions provided in Windows Azure Projects Contribution Guidelines.

      If you encounter any bugs with the library please file an issue in the Issues section of the project.

      Learn More

      Windows Azure Node.js Developer Center

Changelog

2012.02.10 Version 0.5.2

• Service Bus Wrappers
• Storage Services UT run against a mock server.
• Node.exe version requirement lowered to raise compatibility.
• Multiple Bugfixes