Add instrumentation data to the analysis server diagnostics page.

pkg/analyzer/lib/instrumentation/instrumentation.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library analyzer.instrumentation.instrumentation;
 
 import 'dart:async';
 import 'dart:convert';
 
 import 'package:analyzer/task/model.dart';
@@ skipping 10 matching lines @@
  * The interface used by client code to communicate with an instrumentation
  * server.
  */
 abstract class InstrumentationServer {
   /**
    * Return the identifier used to identify the current session.
    */
   String get sessionId;
 
   /**
+   * A user-friendly description of this instrumentation server.
+   */
+  String get describe => '${toString()}, session $sessionId';

[Brian Wilkerson, 2017/02/27 14:41:32]

Personally, I would create a method other than `toString` (`destination`?) to
invoke here, then override that method in most subclasses (rather than
`describe`). (Doesn't apply to MulticastInstrumentationServer, which still needs
to override `describe`.)

[devoncarew, 2017/03/01 01:51:32]

I changed this to a purely abstract method (String get describe);
implementations will need to fill it in (it seems like the session id was not
used for most instrumentation server implementations).

+
+  /**
    * Pass the given [message] to the instrumentation server so that it will be
    * logged with other messages.
    *
    * This method should be used for most logging.
    */
   void log(String message);
 
   /**
    * Pass the given [message] to the instrumentation server so that it will be
    * logged with other messages.
@@ skipping 62 matching lines @@
   /**
    * Return the identifier used to identify the current session.
    */
   String get sessionId => _instrumentationServer?.sessionId ?? '';
 
   /**
    * The current time, expressed as a decimal encoded number of milliseconds.
    */
   String get _timestamp => new DateTime.now().millisecondsSinceEpoch.toString();
 
+  InstrumentationServer get instrumentationServer => _instrumentationServer;
+
   /**
    * Log that the given analysis [task] is being performed in the given
    * [context].
    */
   void logAnalysisTask(String context, AnalysisTask task) {
     if (_instrumentationServer != null) {
       _instrumentationServer
           .log(_join([TAG_ANALYSIS_TASK, context, task.description]));
     }
   }
@@ skipping 240 matching lines @@
  */
 class MulticastInstrumentationServer implements InstrumentationServer {
   final List<InstrumentationServer> _servers;
 
   MulticastInstrumentationServer(this._servers);
 
   @override
   String get sessionId => _servers[0].sessionId;
 
   @override
+  String get describe {
+    return _servers
+        .map((InstrumentationServer server) => server.describe)
+        .join("\n");
+  }
+
+  @override
   void log(String message) {
     for (InstrumentationServer server in _servers) {
       server.log(message);
     }
   }
 
   @override
   void logWithPriority(String message) {
     for (InstrumentationServer server in _servers) {
       server.logWithPriority(message);
     }
   }
 
   @override
   Future shutdown() async {
     for (InstrumentationServer server in _servers) {
       await server.shutdown();
     }
   }
 }