Major updates to API and structure.

Updated the API to be more node friendly; restructured to simplify
validations; updated request handling to cover an edge case where data
could become corrupt; requests now correctly speficy JSON content-type;
and added tests.

Author: fiveisprime

.gitignore

@@ -0,0 +1,37 @@
+# Logs
+logs
+*.log
+npm-debug.log*
+
+# Runtime data
+pids
+*.pid
+*.seed
+
+# Directory for instrumented libs generated by jscoverage/JSCover
+lib-cov
+
+# Coverage directory used by tools like istanbul
+coverage
+
+# nyc test coverage
+.nyc_output
+
+# Grunt intermediate storage (http://gruntjs.com/creating-plugins#storing-task-files)
+.grunt
+
+# node-waf configuration
+.lock-wscript
+
+# Compiled binary addons (http://nodejs.org/api/addons.html)
+build/Release
+
+# Dependency directories
+node_modules
+jspm_packages
+
+# Optional npm cache directory
+.npm
+
+# Optional REPL history
+.node_repl_history

.npmignore

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+samples
+test

README.md

@@ -1,28 +1,52 @@
 LUIS
 ==============
-LUIS is a service for language understanding that provides intent classification and entity extraction.
-In order to use the SDK you first need to create and publish an app on www.luis.ai where you will get your appId and appKey and input their values in the sample application file "sample.js".
 
-The SDK
---------------
-The SDK can be used by creating 2 callback functions "onSuccess" and "onFailure" and passing them to the "predict" and "reply" functions to be called asynchronously in the cases of the request success or failure.
+LUIS is a service for language understanding that provides intent classification
+and entity extraction. In order to use the SDK you first need to create and
+publish an app on www.luis.ai where you will get your `appId` and `appKey` and
+input their values in the sample application file "sample.js".
+
+
+## Usage
+
+```js
+const client = require('luis-sdk')({
+  appId: 'your app ID',
+  appKey: 'your app key',
+  verbose: true
+})
+
+client.predict('Enter text to predict', (err, response) => {
+  if (err) throw err
+
+  console.dir(response)
+
+  response.entities.forEach((e, i) => {
+    console.log(`${i + 1} - ${e.entity}`)
+  })
+})
+
+```
+
+## Sample Application
+
+The sample application allows you to perform the Predict and Reply operations and
+to view the following parts of the parsed response:
 
-Sample Application
---------------
-The sample application allows you to perform the Predict and Reply operations and to view the following parts of the parsed response:
 - Query
 - Top Intent
 - Entities
-- Dialog status, parameter name, and prompt 
+- Dialog status, parameter name, and prompt
 
 License
 =======
 
-All Microsoft Cognitive Services SDKs and samples are licensed with the MIT License. For more details, see
-[LICENSE](</LICENSE.md>).
+All Microsoft Cognitive Services SDKs and samples are licensed with the MIT
+License. For more details, see [LICENSE](</LICENSE.md>).
 
 Developer Code of Conduct
 =======
 
-Developers using Cognitive Services, including this client library & sample, are required to follow the “[Developer Code of Conduct for Microsoft Cognitive Services](http://go.microsoft.com/fwlink/?LinkId=698895)”.
-
+Developers using Cognitive Services, including this client library & sample, are
+required to follow the “[Developer Code of Conduct for Microsoft Cognitive
+Services](http://go.microsoft.com/fwlink/?LinkId=698895)”.

index.js

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+'use strict'
+
+const Assert = require('assert')
+const Https = require('https')
+const Util = require('util')
+
+const Concat = require('concat-stream')
+
+const LUISURL = 'api.projectoxford.ai'
+const LUISPredictMask = '/luis/v2.0/apps/%s?subscription-key=%s&q=%s&verbose=%s'
+const LUISReplyMask = '/luis/v2.0/apps/%s?subscription-key=%s&q=%s&contextid=%s&verbose=%s'
+
+/**
+ * Sends an API request.
+ *
+ * @param {object} options - Request options.
+ * @param {function} done - Callback function.
+ */
+function sendRequest (options, done) {
+  let req = Https.request(options, (response) => {
+    response.pipe(Concat((data) => {
+      let body
+      data = data.toString()
+
+      if (data && data.length > 0) {
+        body = JSON.parse(data)
+
+        if (response.statusCode !== 200) return done(new Error(body.message))
+
+        return done(null, body)
+      }
+
+      done(new Error('Invalid or empty response from LUIS.'))
+    }))
+  })
+
+  req.on('error', done.bind(null))
+  req.end()
+}
+
+/**
+ * This is the interface of the LUIS SDK
+ * Constructs a LUISClient with the corresponding user's App ID and Subscription
+ * Keys.
+ *
+ * @param {object} initData - Configuration object to initialize the client.
+ * @param {string} initData.appId - Application ID for your LUIS app.
+ * @param {String} initData.appKey - Application Key for your LUIS app.
+ * @param {boolean} initData.verbose - Whether to receive verbose output.
+ * @returns {{predict: function, reply: function}} - Interface methods.
+ */
+module.exports = (initData) => {
+  Assert.ok(initData, 'Configuration object required to initialize LUIS Client')
+  Assert.ok(initData.appId, 'You must specify an \'appId\'')
+  Assert.ok(initData.appKey, 'You must specify an \'appKey\'')
+
+  initData.verbose = Boolean(initData.verbose || true)
+
+  return {
+    /**
+     * Initiates the prediction procedure.
+     *
+     * @param {string} text - The text to be analyzed and predicted.
+     * @param {function} done - Callback function.
+     */
+    predict: (text, done) => {
+      if (!text) return done(new Error('Text  cannot be empty'))
+
+      let options = {
+        hostname: LUISURL,
+        path: Util.format(LUISPredictMask, initData.appId, initData.appKey, encodeURIComponent(text), initData.verbose),
+        method: 'GET',
+        headers: { 'Content-Type': 'application/json' }
+      }
+
+      sendRequest(options, done)
+    },
+    /**
+     * Initiates the prediction procedure
+     *
+     * @param {string} text - The text to be analyzed and predicted.
+     * @param {string} context - Context of the request.
+     * @param {string} forceSet - Optional fording set.
+     * @param {function} done - Callback function.
+     */
+    reply: (text, context, forceSet, done) => {
+      if (!text) return done(new Error('Text cannot be empty'))
+      if (typeof forceSet === 'function') {
+        done = forceSet
+        forceSet = null
+      }
+
+      let options = {
+        hostname: LUISURL,
+        path: Util.format(LUISReplyMask, initData.appId, initData.appKey, encodeURIComponent(text), context, initData.verbose),
+        method: 'GET',
+        headers: { 'Content-Type': 'application/json' }
+      }
+
+      if (forceSet) options.path += `&forceset=${forceSet}`
+
+      sendRequest(options, done)
+    }
+  }
+}