http: do not rely on the 'agentRemove' event

Do not use the `'agentRemove'` event to null `socket._httpMessage` as that event is public and can be used to not keep a request in the agent. Backport-PR-URL: #20786 PR-URL: #20786Fixes: #20690 Reviewed-By: Ruben Bridgewater <[email protected]> Reviewed-By: James M Snell <[email protected]> Reviewed-By: Trivikram Kamat <[email protected]> Reviewed-By: Anatoli Papirovski <[email protected]>

Author: lpinca

lib/_http_agent.js

@@ -277,7 +277,6 @@ function installListeners(agent, s, options){
 s.removeListener('close',onClose);
 s.removeListener('free',onFree);
 s.removeListener('agentRemove',onRemove);
-s._httpMessage=null;
 }
 s.on('agentRemove',onRemove);
 }

lib/_http_client.js

@@ -470,6 +470,7 @@ function socketOnData(d){
 // TODO(isaacs): Need a way to reset a stream to fresh state
 // IE, not flowing, and not explicitly paused.
 socket._readableState.flowing=null;
+socket._httpMessage=null;
 
 req.emit(eventName,res,socket,bodyHead);
 req.emit('close');

test/parallel/test-http-agent-remove.js

@@ -0,0 +1,21 @@
+'use strict';
+const{ mustCall }=require('../common');
+
+consthttp=require('http');
+const{ strictEqual }=require('assert');
+
+constserver=http.createServer(mustCall((req,res)=>{
+res.flushHeaders();
+}));
+
+server.listen(0,mustCall(()=>{
+constreq=http.get({
+port: server.address().port
+},mustCall(()=>{
+const{ socket }=req;
+socket.emit('agentRemove');
+strictEqual(socket._httpMessage,req);
+socket.destroy();
+server.close();
+}));
+}));