Use http agents for hook requests (#4791)

src/Controllers/HooksController.js

@@ -6,18 +6,26 @@ import * as Parse           from "parse/node";
 // @flow-disable-next
 import * as request         from "request";
 import { logger }           from '../logger';
+import http                 from 'http';
+import https                from 'https';
 
 const DefaultHooksCollectionName = "_Hooks";
+const HTTPAgents = {
+  http: new http.Agent({ keepAlive: true }),
+  https: new https.Agent({ keepAlive: true }),
+}
 
 export class HooksController {
   _applicationId:string;
   _webhookKey:string;
   database: any;
+  keepAlive: boolean;
 
-  constructor(applicationId:string, databaseController, webhookKey) {
+  constructor(applicationId:string, databaseController, webhookKey, keepAlive) {
     this._applicationId = applicationId;
     this._webhookKey = webhookKey;
     this.database = databaseController;
+    this.keepAlive = keepAlive;
   }
 
   load() {
@@ -85,7 +93,7 @@ export class HooksController {
   }
 
   addHookToTriggers(hook) {
-    var wrappedFunction = wrapToHTTPRequest(hook, this._webhookKey);
+    var wrappedFunction = wrapToHTTPRequest(hook, this._webhookKey, this.keepAlive);
     wrappedFunction.url = hook.url;
     if (hook.className) {
       triggers.addTrigger(hook.triggerName, hook.className, wrappedFunction, this._applicationId)
@@ -159,7 +167,7 @@ export class HooksController {
   }
 }
 
-function wrapToHTTPRequest(hook, key) {
+function wrapToHTTPRequest(hook, key, keepAlive) {
   return (req, res) => {
     const jsonBody = {};
     for (var i in req) {
@@ -177,9 +185,14 @@ function wrapToHTTPRequest(hook, key) {
       headers: {
         'Content-Type': 'application/json'
       },
-      body: JSON.stringify(jsonBody)
+      body: JSON.stringify(jsonBody),
     };
 
+    if (keepAlive) {
+      const agent = hook.url.startsWith('https') ? HTTPAgents['https'] : HTTPAgents['http'];
+      jsonRequest.agent = agent;
+    }
+
     if (key) {
       jsonRequest.headers['X-Parse-Webhook-Key'] = key;
     } else {

src/Controllers/index.js

@@ -149,9 +149,10 @@ export function getDatabaseController(options: ParseServerOptions, cacheControll
 export function getHooksController(options: ParseServerOptions, databaseController: DatabaseController): HooksController {
   const {
     appId,
-    webhookKey
+    webhookKey,
+    hookKeepAlive,
   } = options;
-  return new HooksController(appId, databaseController, webhookKey);
+  return new HooksController(appId, databaseController, webhookKey, hookKeepAlive);
 }
 
 interface PushControlling {
@@ -228,4 +229,3 @@ export function getDatabaseAdapter(databaseURI, collectionPrefix, databaseOption
     });
   }
 }
-

src/Options/index.js

@@ -131,6 +131,8 @@ export interface ParseServerOptions {
   startLiveQueryServer: ?boolean;
   /* Live query server configuration options (will start the liveQuery server) */
   liveQueryServerOptions: ?LiveQueryServerOptions;
+  /* Keep hook HTTP connections alive */
+  hookKeepAlive: ?boolean;
 
   __indexBuildCompletionCallbackForTests: ?()=>void;
 }