Adds ability to specifiy a custom user agent to be appended to user a…

…gent headers.

lib/config.js

@@ -54,6 +54,9 @@ require('./credentials/credential_provider_chain');
  *     requests that fail because of an skewed client clock. Defaults to
  *     `false`.
  *
+ * @!attribute customUserAgent
+ *   @return [String] a custom identifier to append to user agent headers.
+ *
  * @!attribute sslEnabled
  *   @return [Boolean] whether SSL is enabled for requests
  *
@@ -150,6 +153,8 @@ AWS.Config = AWS.util.inherit({
    * @option options correctClockSkew [Boolean] whether to apply a clock skew
    *     correction and retry requests that fail because of an skewed client
    *     clock. Defaults to `false`.
+   * @option options customUserAgent [String] A custom identifier to append to
+   *     user agent headers.
    * @option options s3ForcePathStyle [Boolean] whether to force path
    *   style URLs for S3 objects.
    * @option options s3BucketEndpoint [Boolean] whether the provided endpoint
@@ -405,6 +410,7 @@ AWS.Config = AWS.util.inherit({
     computeChecksums: true,
     convertResponseTypes: true,
     correctClockSkew: false,
+    customUserAgent: null,
     dynamoDbCrc32: true,
     systemClockOffset: 0,
     signatureVersion: null,

lib/http.js

@@ -92,23 +92,24 @@ AWS.HttpRequest = inherit({
   /**
    * @api private
    */
-  constructor: function HttpRequest(endpoint, region) {
+  constructor: function HttpRequest(endpoint, region, customUserAgent) {
     endpoint = new AWS.Endpoint(endpoint);
     this.method = 'POST';
     this.path = endpoint.path || '/';
     this.headers = {};
     this.body = '';
     this.endpoint = endpoint;
     this.region = region;
-    this.setUserAgent();
+    this.setUserAgent(customUserAgent);
   },
 
   /**
    * @api private
    */
-  setUserAgent: function setUserAgent() {
+  setUserAgent: function setUserAgent(customUserAgent) {
     var prefix = AWS.util.isBrowser() ? 'X-Amz-' : '';
-    this.headers[prefix + 'User-Agent'] = AWS.util.userAgent();
+    var customSuffix = (typeof customUserAgent === 'string' && customUserAgent) ? '/' + customUserAgent : '';
+    this.headers[prefix + 'User-Agent'] = AWS.util.userAgent() + customSuffix;
   },
 
   /**

lib/request.js

@@ -304,6 +304,7 @@ AWS.Request = inherit({
   constructor: function Request(service, operation, params) {
     var endpoint = service.endpoint;
     var region = service.config.region;
+    var customUserAgent = service.config.customUserAgent;
 
     // global endpoints sign as us-east-1
     if (service.isGlobalEndpoint) region = 'us-east-1';
@@ -312,7 +313,7 @@ AWS.Request = inherit({
     this.service = service;
     this.operation = operation;
     this.params = params || {};
-    this.httpRequest = new AWS.HttpRequest(endpoint, region);
+    this.httpRequest = new AWS.HttpRequest(endpoint, region, customUserAgent);
     this.startTime = AWS.util.date.getDate();
 
     this.response = new AWS.Response(this);

test/config.spec.coffee

@@ -84,6 +84,10 @@ describe 'AWS.Config', ->
     it 'defaults to false', ->
       expect(configure().correctClockSkew).to.equal(false)
 
+  describe 'customUserAgent', ->
+    it 'defaults to null', ->
+      expect(configure().customUserAgent).to.equal(null)
+
   describe 'set', ->
     it 'should set a default value for a key', ->
       config = new AWS.Config()

test/http_request.spec.coffee

@@ -25,6 +25,12 @@ describe 'AWS.HttpRequest', ->
       headers[agentHeader] = AWS.util.userAgent()
       expect(request.headers).to.eql(headers)
 
+    it 'adds the customUserAgent to the user agent header if provided', ->
+      headers = {}
+      headers[agentHeader] = AWS.util.userAgent() + '/custom'
+      request = new AWS.HttpRequest('http://domain.com', '', 'custom')
+      expect(request.headers).to.eql(headers)
+
     it 'defaults body to empty string', ->
       expect(request.body).to.equal('')