Merge pull request #4435 from murgatroid99/node_interop_server_response_delay

Added support for ResponseParameters.interval_us to the Node interop server

src/node/interop/async_delay_queue.js

+/*
+ *
+ * Copyright 2015, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+'use strict';
+
+var _ = require('lodash');
+
+/**
+ * This class represents a queue of callbacks that must happen sequentially, each
+ * with a specific delay after the previous event.
+ */
+function AsyncDelayQueue() {
+  this.queue = [];
+
+  this.callback_pending = false;
+}
+
+/**
+ * Run the next callback after its corresponding delay, if there are any
+ * remaining.
+ */
+AsyncDelayQueue.prototype.runNext = function() {
+  var next = this.queue.shift();
+  var continueCallback = _.bind(this.runNext, this);
+  if (next) {
+    this.callback_pending = true;
+    setTimeout(function() {
+      next.callback(continueCallback);
+    }, next.delay);
+  } else {
+    this.callback_pending = false;
+  }
+};
+
+/**
+ * Add a callback to be called with a specific delay after now or after the
+ * current last item in the queue or current pending callback, whichever is
+ * latest.
+ * @param {function(function())} callback The callback
+ * @param {Number} The delay to apply, in milliseconds
+ */
+AsyncDelayQueue.prototype.add = function(callback, delay) {
+  this.queue.push({callback: callback, delay: delay});
+  if (!this.callback_pending) {
+    this.runNext();
+  }
+};
+
+module.exports = AsyncDelayQueue;

src/node/interop/interop_server.js

@@ -36,6 +36,7 @@
 var fs = require('fs');
 var path = require('path');
 var _ = require('lodash');
+var AsyncDelayQueue = require('./async_delay_queue');
 var grpc = require('..');
 var testProto = grpc.load({
   root: __dirname + '/../../..',
@@ -155,6 +156,7 @@ function handleStreamingInput(call, callback) {
  */
 function handleStreamingOutput(call) {
   echoHeader(call);
+  var delay_queue = new AsyncDelayQueue();
   var req = call.request;
   if (req.response_status) {
     var status = req.response_status;
@@ -163,9 +165,15 @@ function handleStreamingOutput(call) {
     return;
   }
   _.each(req.response_parameters, function(resp_param) {
-    call.write({payload: getPayload(req.response_type, resp_param.size)});
+    delay_queue.add(function(next) {
+      call.write({payload: getPayload(req.response_type, resp_param.size)});
+      next();
+    }, resp_param.interval_us);
+  });
+  delay_queue.add(function(next) {
+    call.end(getEchoTrailer(call));
+    next();
   });
-  call.end(getEchoTrailer(call));
 }
 
 /**
@@ -175,6 +183,7 @@ function handleStreamingOutput(call) {
  */
 function handleFullDuplex(call) {
   echoHeader(call);
+  var delay_queue = new AsyncDelayQueue();
   call.on('data', function(value) {
     if (value.response_status) {
       var status = value.response_status;
@@ -183,11 +192,17 @@ function handleFullDuplex(call) {
       return;
     }
     _.each(value.response_parameters, function(resp_param) {
-      call.write({payload: getPayload(value.response_type, resp_param.size)});
+      delay_queue.add(function(next) {
+        call.write({payload: getPayload(value.response_type, resp_param.size)});
+        next();
+      }, resp_param.interval_us);
     });
   });
   call.on('end', function() {
-    call.end(getEchoTrailer(call));
+    delay_queue.add(function(next) {
+      call.end(getEchoTrailer(call));
+      next();
+    });
   });
 }