child_process: allow 'http_parser' monkey patching again

Lazy load _http_common and HTTPParser so that the 'http_parser' binding can be monkey patched before any internal modules require it. This also probably improves startup performance minimally for programs that never require the HTTP stack. Fixes: #23716Fixes: creationix/http-parser-js#57 PR-URL: #24006 Reviewed-By: Joyee Cheung <[email protected]> Reviewed-By: James M Snell <[email protected]> Reviewed-By: Colin Ihrig <[email protected]>

Author: Jimbly

lib/internal/child_process.js

@@ -38,8 +38,6 @@ const{owner_symbol } = require('internal/async_hooks').symbols;
 const{ convertToValidSignal }=require('internal/util');
 const{ isArrayBufferView }=require('internal/util/types');
 constspawn_sync=internalBinding('spawn_sync');
-const{ HTTPParser }=internalBinding('http_parser');
-const{ freeParser }=require('_http_common');
 const{ kStateSymbol }=require('internal/dgram');
 
 const{
@@ -57,6 +55,10 @@ const{SocketListSend, SocketListReceive } = SocketList;
 
 // Lazy loaded for startup performance.
 letStringDecoder;
+// Lazy loaded for startup performance and to allow monkey patching of
+// internalBinding('http_parser').HTTPParser.
+letfreeParser;
+letHTTPParser;
 
 constMAX_HANDLE_RETRANSMISSIONS=3;
 
@@ -121,6 +123,12 @@ const handleConversion ={
 handle.onread=nop;
 socket._handle=null;
 socket.setTimeout(0);
+
+if(freeParser===undefined)
+freeParser=require('_http_common').freeParser;
+if(HTTPParser===undefined)
+HTTPParser=internalBinding('http_parser').HTTPParser;
+
 // In case of an HTTP connection socket, release the associated
 // resources
 if(socket.parser&&socket.parserinstanceofHTTPParser){

test/parallel/test-http-parser-lazy-loaded.js

@@ -0,0 +1,37 @@
+// Flags: --expose-internals
+
+'use strict';
+
+const{ internalBinding }=require('internal/test/binding');
+
+// Monkey patch before requiring anything
+classDummyParser{
+constructor(type){
+this.test_type=type;
+}
+}
+DummyParser.REQUEST=Symbol();
+internalBinding('http_parser').HTTPParser=DummyParser;
+
+constcommon=require('../common');
+constassert=require('assert');
+const{ spawn }=require('child_process');
+const{ parsers }=require('_http_common');
+
+// Test _http_common was not loaded before monkey patching
+constparser=parsers.alloc();
+assert.strictEqual(parserinstanceofDummyParser,true);
+assert.strictEqual(parser.test_type,DummyParser.REQUEST);
+
+if(process.argv[2]!=='child'){
+// Also test in a child process with IPC (specific case of https://github.com/nodejs/node/issues/23716)
+constchild=spawn(process.execPath,[
+'--expose-internals',__filename,'child'
+],{
+stdio: ['inherit','inherit','inherit','ipc']
+});
+child.on('exit',common.mustCall((code,signal)=>{
+assert.strictEqual(code,0);
+assert.strictEqual(signal,null);
+}));
+}