Converted Observatory logging-page element

runtime/observatory/lib/src/elements/logging_list.dart

+// Copyright (c) 2015, 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 logging_page;
+
+import 'dart:async';
+import 'dart:html';
+import 'package:logging/logging.dart';
+import 'package:observatory/models.dart' as M;
+import 'package:observatory/src/elements/helpers/rendering_scheduler.dart';
+import 'package:observatory/src/elements/helpers/tag.dart';
+import 'package:observatory/utils.dart';
+
+class LoggingListElement extends HtmlElement implements Renderable {
+  static const tag = const Tag<LoggingListElement>('logging-list');
+
+  RenderingScheduler<LoggingListElement> _r;
+
+  Stream<RenderedEvent<LoggingListElement>> get onRendered => _r.onRendered;
+
+  M.IsolateRef _isolate;
+  M.EventRepository _events;
+  StreamSubscription _subscription;
+  Level _level = Level.ALL;
+  final _logs = <Map>[];
+
+  M.IsolateRef get isolate => _isolate;
+  Level get level => _level;
+
+  set level(Level value) => _level = _r.checkAndReact(_level, value);
+
+  factory LoggingListElement(M.IsolateRef isolate,
+                             M.EventRepository events,
+                             {RenderingQueue queue}) {
+    assert(isolate != null);
+    assert(events != null);
+    LoggingListElement e = document.createElement(tag.name);
+    e._r = new RenderingScheduler(e, queue: queue);
+    e._isolate = isolate;
+    e._events = events;
+    return e;
+  }
+
+  LoggingListElement.created() : super.created();
+
+  @override
+  attached() {
+    super.attached();
+    _r.enable();
+    _subscription = _events.onLoggingEvent.listen((e) {
+      if (e.isolate.id == _isolate.id) {
+        _logs.add(e.logRecord);
+        if (_shouldBeVisible(_logs.last)) {
+          _r.dirty();
+        }
+      }
+    });
+  }
+
+  @override
+  detached() {
+    super.detached();
+    _r.disable(notify: true);
+    children = [];
+    _subscription.cancel();
+  }
+
+  void render() {
+    children = _logs.where(_shouldBeVisible).map((logRecord) =>
+      new DivElement()..classes = ['logItem', logRecord['level'].name]
+        ..children = [
+          new SpanElement()..classes = ['level']
+            ..text = logRecord['level'].name,
+          new SpanElement()..classes = ['time']
+            ..text = Utils.formatDateTime(logRecord['time']),
+          new SpanElement()..classes = ['message']
+            ..text = logRecord["message"].valueAsString
+        ]
+    ).toList();
+  }
+
+  bool _shouldBeVisible(Map record) => _level.compareTo(record['level']) <= 0;
+}