Examples.md

Examples

All of these examples assume that the AWS library is required, credentials are loaded via environment variables (AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY), and the region is set via AWS.config.update({region: 'us-west-2'}); or the AWS_REGION environment variable.

The common preamble code can be summarized as follows:

var AWS = require('aws-sdk');
AWS.config.update({region: 'us-west-2'});

Amazon Simple Storage Service (Amazon S3)

Amazon S3: List All of Your Buckets (listBuckets)

The following example lists all buckets associated with your AWS account:

var s3 = new AWS.S3();
s3.client.listBuckets(function(err, data) {
  for (var index in data.Buckets) {
    var bucket = data.Buckets[index];
    console.log("Bucket: ", bucket.Name, ' : ', bucket.CreationDate);
  }
});

Amazon S3: Create a New Bucket and Object (createBucket, putObject)

The following example puts the string 'Hello!' inside the object 'myKey' of bucket 'myBucket':

var s3 = new AWS.S3();
s3.client.createBucket({Bucket: 'myBucket'}, function() {
  var data = {Bucket: 'myBucket', Key: 'myKey', Body: 'Hello!'};
  s3.client.putObject(data, function() {
    console.log("Successfully uploaded data to myBucket/myKey");
  });
});

Amazon S3: Streaming Objects to Files on Disk (getObject)

You can use the createReadStream() method on a request object to get a handle to a stream object which supports piping raw HTTP body data to a file. This is especially useful when streaming objects to streams like filesystem objects. The following example shows how you can stream an object from Amazon S3 directly to a file on disk:

var s3 = new AWS.S3();
var params = {Bucket: 'myBucket', Key: 'myImageFile.jpg'};
var file = require('fs').createWriteStream('/path/to/file.jpg');
s3.client.getObject(params).createReadStream().pipe(file);

Alternatively, you can register an 'httpData' event listener on the request object to access each chunk of data received across the wire (as Buffer objects):

var s3 = new AWS.S3();
var params = {Bucket: 'myBucket', Key: 'myImageFile.jpg'};
var file = require('fs').createWriteStream('/path/to/file.jpg');

s3.client.getObject(params).
on('httpData', function(chunk) { file.write(chunk); }).
on('httpDone', function() { file.end(); }).
send();

Amazon DynamoDB

Amazon DynamoDB: Listing Tables (listTables)

The following example will list all tables in a DynamoDB instance:

var db = new AWS.DynamoDB();
db.client.listTables(function(err, data) {
  console.log(data.TableNames);
});

Amazon Glacier

Amazon Glacier: Creating a Vault

The following example creates a vault named "YOUR_VAULT_NAME":

var glacier = new AWS.Glacier();
glacier.client.createVault({vaultName: 'YOUR_VAULT_NAME'}, function(err) {
  if (!err) console.log("Created vault!")
});

Amazon Glacier: Uploading an Archive

Note: this example assumes you have already created a vault named "YOUR_VAULT_NAME".

The following example will upload a single Buffer object as an entire archive. The SDK will automatically compute the tree hash checksum for the data being uploaded, though you can override it by passing your own checksum parameter.

var glacier = new AWS.Glacier(),
    vaultName = 'YOUR_VAULT_NAME',
    buffer = new Buffer(2.5 * 1024 * 1024); // 2.5MB buffer

var params = {vaultName: vaultName, body: buffer};
glacier.client.uploadArchive(params, function(err, data) {
  if (err) console.log("Error uploading archive!", err);
  else console.log("Archive ID", data.archiveId);
});

Amazon Glacier: Multi-part Upload

Note: this example assumes you have already created a vault named "YOUR_VAULT_NAME".

The following example will create a multi-part upload out of 1MB chunks of a Buffer object. Note that a complete SHA-256 tree hash is manually computed using the computeChecksums method:

var glacier = new AWS.Glacier(),
    vaultName = 'YOUR_VAULT_NAME',
    buffer = new Buffer(2.5 * 1024 * 1024), // 2.5MB buffer
    partSize = 1024 * 1024, // 1MB chunks,
    numPartsLeft = Math.ceil(buffer.length / partSize),
    startTime = new Date(),
    params = {vaultName: vaultName, partSize: partSize.toString()};

// Compute the complete SHA-256 tree hash so we can pass it
// to completeMultipartUpload request at the end
var treeHash = glacier.client.computeChecksums(buffer).treeHash;

// Initiate the multi-part upload
console.log('Initiating upload to', vaultName);
glacier.client.initiateMultipartUpload(params, function (mpErr, multipart) {
  if (mpErr) { console.log('Error!', mpErr.stack); return; }
  console.log("Got upload ID", multipart.uploadId);

  // Grab each partSize chunk and upload it as a part
  for (var i = 0; i < buffer.length; i += partSize) {
    var end = Math.min(i + partSize, buffer.length),
        partParams = {
          vaultName: vaultName,
          uploadId: multipart.uploadId,
          range: 'bytes ' + i + '-' + (end-1) + '/*',
          body: buffer.slice(i, end)
        };

    // Send a single part
    console.log('Uploading part', i, '=', partParams.range);
    glacier.client.uploadMultipartPart(partParams, function(multiErr, mData) {
      if (multiErr) return;
      console.log("Completed part", this.request.params.range);
      if (--numPartsLeft > 0) return; // complete only when all parts uploaded

      var doneParams = {
        vaultName: vaultName,
        uploadId: multipart.uploadId,
        archiveSize: buffer.length.toString(),
        checksum: treeHash // the computed tree hash
      };

      console.log("Completing upload...");
      glacier.client.completeMultipartUpload(doneParams, function(err, data) {
        if (err) {
          console.log("An error occurred while uploading the archive");
          console.log(err);
        } else {
          var delta = (new Date() - startTime) / 1000;
          console.log('Completed upload in', delta, 'seconds');
          console.log('Archive ID:', data.archiveId);
          console.log('Checksum:  ', data.checksum);
        }
      });
    });
  }
});

Using Proxies

Setting a Global Proxy

If you cannot connect to the internet directly, the SDK supports the use of HTTP or HTTPS proxies through global or per-service configuration options. To set a proxy, pass the proxy option to the httpOptions setting of your config object. This is how you could set a global proxy:

AWS.config.update({
  httpOptions: {
    proxy: 'http://localhost:8080'
  }
});

var s3 = new AWS.S3();
s3.client.getObject({Bucket: 'bucket', Key: 'key'}, function (err, data) {
  console.log(err, data);
});

Setting a Per-Service Proxy

If you want to use a proxy on a per-service basis, you can also pass this same configuration option to the service constructor:

var s3 = new AWS.S3({httpOptions: {proxy: 'http://localhost:8080'}});
s3.client.getObject({Bucket: 'bucket', Key: 'key'}, function (err, data) {
  console.log(err, data);
});