Add top and skip search options

lib/bing.js

@@ -10,107 +10,128 @@ var request = require('request'),
     qs = require('querystring');
 
 /**
- * @param {Object} options  Options to all Bing calls, allows overriding of rootUri,
+ * @param {Object} options  Options to all Bing calls, allows overriding of
- *  accKey (Bing API key), userAgent, reqTimeout
+ *        rootUri, accKey (Bing API key), userAgent, reqTimeout
  * @returns {Bing}
  * @constructor
  */
 var Bing = function( options ) {
 
-    if( !(this instanceof Bing) ) return new Bing( options );
+  if( !(this instanceof Bing) ) return new Bing( options );
 
-    var defaults = {
+  var defaults = {
 
-        //Bing Search API URI
+    //Bing Search API URI
-        rootUri: "https://api.datamarket.azure.com/Bing/Search/",
+    rootUri: "https://api.datamarket.azure.com/Bing/Search/",
-        //TODO move the web part, to choose also Images
 
-        //Account Key
+    //Account Key
-        accKey: null,
+    accKey: null,
- 
-        //Bing UserAgent
-        userAgent: 'Bing Search Client for Node.js',
 
-        //Request Timeout
+    //Bing UserAgent
-        reqTimeout: 5000
+    userAgent: 'Bing Search Client for Node.js',
-    };
 
-    //merge options passed in with defaults
+    //Request Timeout
-    this.options = _.extend(defaults, options);
+    reqTimeout: 5000,
 
-    this.searchVertical = function(query, vertical, callback, options) {
+    // Number of results (limited to 50 by API)
-        if(typeof callback != 'function') {
+    top: 50,
-            throw "Error: Callback function required!";
-        }
 
-        // TODO check if valid options
+    // Number of skipped results (pagination)
+    skip: 0
 
-        var opts = this.options;
+  };
 
-        if (options !== null) {
+  //merge options passed in with defaults
-            opts = _.extend(this.options, options);
+  this.options = _.extend(defaults, options);
-        }
 
-        var reqUri = opts.rootUri + vertical +
+  this.searchVertical = function(query, vertical, callback, options) {
-            "?$format=json&" +
-            qs.stringify({ "Query": "'" + query + "'" });
 
-        request({
+    if(typeof callback != 'function') {
-            uri: reqUri,
+      throw "Error: Callback function required!";
-            method: opts.method || "GET",
+    }
-            headers: {
-                "User-Agent": opts.userAgent
-            },
-            auth: {
-                user: opts.accKey,
-                pass: opts.accKey
-            },
-            timeout: opts.reqTimeout
 
-        }, function(err, res, body){
+    var opts = this.options;
 
-            // Parse body, if body
+    if (options !== null) {
-            body = typeof body === 'string' ?
+      opts = _.extend(this.options, options);
-                JSON.parse(body) :
+    }
-                body;
 
-            callback(err, res, body);
+    var reqUri = opts.rootUri
-        });
+                   + vertical
-    };
+                   + "?$format=json&"
+                   + qs.stringify({ "Query": "'" + query + "'" })
+                   + "&$top=" + opts.top
+                   + "&$skip=" + opts.skip;
+
+    request({
+      uri: reqUri,
+      method: opts.method || "GET",
+      headers: {
+        "User-Agent": opts.userAgent
+      },
+      auth: {
+        user: opts.accKey,
+        pass: opts.accKey
+      },
+      timeout: opts.reqTimeout
+
+    }, function(err, res, body){
+
+      // Parse body, if body
+      body = typeof body === 'string'
+               ? JSON.parse(body)
+               : body;
+
+      callback(err, res, body);
+    });
+  };
 
 };
 
+
 /**
  * @callback requestCallback
- * @param {String} error        Error evaluates to true when an error has occurred.
+ * @param {String} error     Error evaluates to true when an error has occurred.
- * @param {Object} response     Response object from the Bing call.
+ * @param {Object} response  Response object from the Bing call.
- * @param {Object} body         JSON of the response.
+ * @param {Object} body      JSON of the response.
  */
 
+
 /**
  * Performs a Bing search in the Web vertical.
  *
- * @param {String} query                Query term to search for.
+ * @param {String} query              Query term to search for.
- * @param {requestCallback} callback    Callback called with (potentially json-parsed) response.
+ *
- * @param {Object} options              Options to command, allows overriding of rootUri,
+ * @param {requestCallback} callback  Callback called with (potentially
- *  accKey (Bing API key), userAgent, reqTimeout
+ *                                    json-parsed) response.
+ *
+ * @param {Object} options            Options to command, allows overriding
+ *                                    of rootUri, accKey (Bing API key),
+ *                                    userAgent, reqTimeout, top, skip
  * @function
  */
 Bing.prototype.search = function(query, callback, options) {
     this.searchVertical(query, "Web", callback, options);
 };
 
+
 /**
  * Performs a Bing search in the Images vertical.
  *
- * @param {String} query                Query term to search for.
+ * @param {String} query              Query term to search for.
- * @param {requestCallback} callback    Callback called with (potentially json-parsed) response.
+ *
- * @param {Object} options              Options to command, allows overriding of rootUri,
+ * @param {requestCallback} callback  Callback called with (potentially
- *  accKey (Bing API key), userAgent, reqTimeout
+ *                                    json-parsed) response.
+ *
+ * @param {Object} options            Options to command, allows overriding of
+ *                                    rootUri, accKey (Bing API key),
+ *                                    userAgent, reqTimeout, top, skip
  * @function
  */
 Bing.prototype.images = function(query, callback, options) {
     this.searchVertical(query, "Image", callback, options);
 };
 
+
 module.exports = Bing;
+