child_process: emit IPC messages on next tick

cjihrig · Myles Borins · commit 0b8124f20572 · 2016-07-12T10:59:43.000-07:00
Currently, if an IPC event handler throws an error, it can cause the message to not be consumed, leading to messages piling up. This commit causes IPC events to be emitted on the next tick, allowing the channel's processing logic to move forward as normal. Fixes: #6561 PR-URL: #6909 Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl> Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Santiago Gimeno <santiago.gimeno@gmail.com>
diff --git a/lib/internal/child_process.js b/lib/internal/child_process.js
@@ -692,7 +692,9 @@ function handleMessage(target, message, handle) {
       message.cmd.slice(0, INTERNAL_PREFIX.length) === INTERNAL_PREFIX) {
     eventName = 'internalMessage';
   }
-  target.emit(eventName, message, handle);
+  process.nextTick(() => {
+    target.emit(eventName, message, handle);
+  });
 }
 
 function nop() { }

Original file line number	Diff line number	Diff line change
`@@ -692,7 +692,9 @@ function handleMessage(target, message, handle) {`
`692`	`692`	`message.cmd.slice(0, INTERNAL_PREFIX.length) === INTERNAL_PREFIX) {`
`693`	`693`	`eventName = 'internalMessage';`
`694`	`694`	`}`
`695`		`- target.emit(eventName, message, handle);`
	`695`	`+ process.nextTick(() => {`
	`696`	`+ target.emit(eventName, message, handle);`
	`697`	`+ });`
`696`	`698`	`}`
`697`	`699`
`698`	`700`	`function nop() { }`