1 files changed, 22 insertions, 7 deletions
diff --git a/platform/node/index.js b/platform/node/index.js
index e36a47943d..5944a0a27d 100644
--- a/platform/node/index.js
+++ b/platform/node/index.js
@@ -19,14 +19,29 @@ var Map = function(options) {
 
     return new constructor(Object.assign(options, {
         request: function(req) {
-            request(req, function() {
+            // Protect against `request` implementations that call the callback synchronously,
+            // call it multiple times, or throw exceptions.
+            // http://blog.izs.me/post/59142742143/designing-apis-for-asynchrony
+
+            var responded = false;
+            var callback = function() {
                 var args = arguments;
-                // Protect against `request` implementations that call the callback synchronously.
-                // http://blog.izs.me/post/59142742143/designing-apis-for-asynchrony
-                process.nextTick(function() {
-                    req.respond.apply(req, args);
-                });
-            });
+                if (!responded) {
+                    responded = true;
+                    process.nextTick(function() {
+                        req.respond.apply(req, args);
+                    });
+                } else {
+                    console.warn('request function responded multiple times; it should call the callback only once');
+                }
+            };
+
+            try {
+                request(req, callback);
+            } catch (e) {
+                console.warn('request function threw an exception; it should call the callback with an error instead');
+                callback(e);
+            }
         }
     }));
 };