src: in api.js add socketConnection function.

 - fixes #165

Author: narekhovhannisyan

lib/api.js

@@ -7,12 +7,21 @@
  */
 
 const QueryString = require('querystring')
-
 const RequestPromise = require('request-promise')
+const socketClient = require('socket.io-client')
+
+const { createAuthorizationQuery, setAuthorization } = require('./auth')
 
-const Auth = require('./auth')
+const {
+  API_HOST,
+  WEB_HOST,
+  HTTP_DEFAULT_OPTIONS,
+  SOCKET_HOST,
+  REND_FINISHED_STATE,
+  REND_NOT_FINISHED_STATE
+} = require('./config')
 
-const { API_HOST, WEB_HOST, HTTP_DEFAULT_OPTIONS } = require('./config')
+const { SocketConnectionError } = require('./util/error')
 
 class Api {
   /**
@@ -80,7 +89,6 @@ class Api {
    */
   unauthorizedRequest (options) {
     const _options = Object.assign({}, HTTP_DEFAULT_OPTIONS, options)
-
     Api.prepareRequest(_options)
 
     return Api.request(_options)
@@ -93,9 +101,8 @@ class Api {
    */
   authorizedRequest (options) {
     const _options = Object.assign({}, HTTP_DEFAULT_OPTIONS, options)
-
     Api.prepareRequest(_options)
-    Auth.setAuthorization(_options, this.signKey, this.clientId)
+    setAuthorization(_options, this.signKey, this.clientId)
 
     return Api.request(_options)
   }
@@ -107,11 +114,40 @@ class Api {
    */
   webRequest (options) {
     const _options = Object.assign({}, HTTP_DEFAULT_OPTIONS, options)
-
     Api.appendURI(_options, WEB_HOST)
 
     return RequestPromise(_options)
   }
+
+  /**
+   * @param {Function} callback - The callback function for handling render status result.
+   * @return {unsubscribe}
+   */
+  socketConnection (callback) {
+    const renderStatus = socketClient(SOCKET_HOST, {
+      query: createAuthorizationQuery(this.clientId, this.signKey)
+    })
+
+    renderStatus.on('error', (error) => callback(new SocketConnectionError(error)))
+    renderStatus.on('event', (status) => {
+      if (status.state === 'rended') {
+        renderStatus.close()
+        return callback(null, REND_FINISHED_STATE)
+      } else {
+        // if `status.state` is not `rended` but percent is 100, then show rend not finished state
+        return callback(null, Math.min(REND_NOT_FINISHED_STATE, status.percent))
+      }
+    })
+
+    // if socket is still open, then force close manually.
+    const unsubscribe = () => {
+      if (renderStatus) {
+        renderStatus.close()
+      }
+    }
+
+    return unsubscribe
+  }
 }
 
 module.exports = new Api()