http2: add diagnostics channel 'http2.server.stream.close'

Signed-off-by: Darshan Sen <raisinten@gmail.com>
PR-URL: #58602
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Stephen Belanger <admin@stephenbelanger.com>

Author: RaisinTen

doc/api/diagnostics_channel.md

@@ -1267,6 +1267,13 @@ Emitted when an error occurs during the processing of a stream on the server.
 
 Emitted when a stream is sent on the server.
 
+`http2.server.stream.close`
+
+*`stream` {ServerHttp2Stream}
+
+Emitted when a stream is closed on the server. The HTTP/2 error code used when
+closing the stream can be retrieved using the `stream.rstCode` property.
+
 #### Modules
 
 > Stability: 1 - Experimental

lib/internal/http2/core.js

@@ -194,6 +194,7 @@ const onServerStreamCreatedChannel = dc.channel('http2.server.stream.created');
 constonServerStreamStartChannel=dc.channel('http2.server.stream.start');
 constonServerStreamErrorChannel=dc.channel('http2.server.stream.error');
 constonServerStreamFinishChannel=dc.channel('http2.server.stream.finish');
+constonServerStreamCloseChannel=dc.channel('http2.server.stream.close');
 
 letdebug=require('internal/util/debuglog').debuglog('http2',(fn)=>{
 debug=fn;
@@ -2017,9 +2018,12 @@ function closeStream(stream, code, rstStreamStatus = kSubmitRstStream) {
 stream.once('finish',finishFn);
 }
 
-if(type===NGHTTP2_SESSION_CLIENT&&
-onClientStreamCloseChannel.hasSubscribers){
-onClientStreamCloseChannel.publish({ stream });
+if(type===NGHTTP2_SESSION_CLIENT){
+if(onClientStreamCloseChannel.hasSubscribers){
+onClientStreamCloseChannel.publish({ stream });
+}
+}elseif(onServerStreamCloseChannel.hasSubscribers){
+onServerStreamCloseChannel.publish({ stream });
 }
 }
 

test/parallel/test-diagnostics-channel-http2-server-stream-close-error.js

@@ -0,0 +1,52 @@
+'use strict';
+
+constcommon=require('../common');
+if(!common.hasCrypto)
+common.skip('missing crypto');
+
+// This test ensures that the built-in HTTP/2 diagnostics channels are reporting
+// the diagnostics messages for the 'http2.server.stream.close' channel when
+// a ServerHttp2Stream is destroyed because of an error.
+
+constassert=require('assert');
+constdc=require('diagnostics_channel');
+consthttp2=require('http2');
+const{ Duplex }=require('stream');
+
+dc.subscribe('http2.server.stream.close',common.mustCall(({ stream })=>{
+// Since ServerHttp2Stream is not exported from any module, this just checks
+// if the stream is an instance of Duplex and the constructor name is
+// 'ServerHttp2Stream'.
+assert.ok(streaminstanceofDuplex);
+assert.strictEqual(stream.constructor.name,'ServerHttp2Stream');
+assert.strictEqual(stream.closed,true);
+assert.strictEqual(stream.destroyed,true);
+
+assert.strictEqual(stream.rstCode,http2.constants.NGHTTP2_INTERNAL_ERROR);
+}));
+
+constserver=http2.createServer();
+
+server.on('stream',common.mustCall((stream)=>{
+letexpectedError;
+
+stream.on('error',common.mustCall((err)=>{
+assert.strictEqual(err,expectedError);
+}));
+
+expectedError=newError('HTTP/2 server stream error');
+stream.destroy(expectedError);
+}));
+
+server.listen(0,common.mustCall(()=>{
+constport=server.address().port;
+constclient=http2.connect(`http://localhost:${port}`);
+
+conststream=client.request({});
+stream.on('error',common.mustCall((err)=>{
+assert.strictEqual(err.code,'ERR_HTTP2_STREAM_ERROR');
+
+client.close();
+server.close();
+}));
+}));

test/parallel/test-diagnostics-channel-http2-server-stream-close.js

@@ -0,0 +1,63 @@
+'use strict';
+
+constcommon=require('../common');
+if(!common.hasCrypto)
+common.skip('missing crypto');
+
+// This test ensures that the built-in HTTP/2 diagnostics channels are reporting
+// the diagnostics messages for the 'http2.server.stream.close' channel when
+// ServerHttp2Streams created by these actions are closed:
+// - in response to an incoming 'stream' event from the client
+// - the server calling ServerHttp2Stream#pushStream()
+
+constCountdown=require('../common/countdown');
+constassert=require('assert');
+constdc=require('diagnostics_channel');
+consthttp2=require('http2');
+const{ Duplex }=require('stream');
+
+constserverHttp2StreamCloseCount=2;
+
+dc.subscribe('http2.server.stream.close',common.mustCall(({ stream })=>{
+// Since ServerHttp2Stream is not exported from any module, this just checks
+// if the stream is an instance of Duplex and the constructor name is
+// 'ServerHttp2Stream'.
+assert.ok(streaminstanceofDuplex);
+assert.strictEqual(stream.constructor.name,'ServerHttp2Stream');
+assert.strictEqual(stream.closed,true);
+assert.strictEqual(stream.destroyed,false);
+
+assert.strictEqual(stream.rstCode,http2.constants.NGHTTP2_NO_ERROR);
+},serverHttp2StreamCloseCount));
+
+constserver=http2.createServer();
+server.on('stream',common.mustCall((stream)=>{
+stream.respond();
+stream.end();
+
+stream.pushStream({},common.mustSucceed((pushStream)=>{
+pushStream.respond();
+pushStream.end();
+}));
+}));
+
+server.listen(0,common.mustCall(()=>{
+constport=server.address().port;
+constclient=http2.connect(`http://localhost:${port}`);
+
+constcountdown=newCountdown(serverHttp2StreamCloseCount,()=>{
+client.close();
+server.close();
+});
+
+conststream=client.request({});
+stream.on('response',common.mustCall(()=>{
+countdown.dec();
+}));
+
+client.on('stream',common.mustCall((pushStream)=>{
+pushStream.on('push',common.mustCall(()=>{
+countdown.dec();
+}));
+}));
+}));