Converted Observatory metrics-page element

runtime/observatory/lib/src/elements/metric/graph.dart

+// Copyright (c) 2016, 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.
+
+import 'dart:html';
+import 'dart:async';
+import 'package:observatory/models.dart' as M;
+import 'package:charted/charted.dart';
+import 'package:observatory/src/elements/helpers/rendering_scheduler.dart';
+import 'package:observatory/src/elements/helpers/tag.dart';
+
+class MetricGraphElement extends HtmlElement implements Renderable {
+  static const tag = const Tag<MetricGraphElement>('metric-graph');
+
+  RenderingScheduler<MetricGraphElement> _r;
+
+  Stream<RenderedEvent<MetricGraphElement>> get onRendered => _r.onRendered;
+
+  M.IsolateRef _isolate;
+  M.Metric _metric;
+  M.MetricRepository _metrics;
+  Timer _timer;
+
+  M.IsolateRef get isolate => _isolate;
+  M.Metric get metric => _metric;
+
+  factory MetricGraphElement(M.IsolateRef isolate, M.Metric metric,
+                               M.MetricRepository metrics,
+                               {RenderingQueue queue}) {
+    assert(isolate != null);
+    assert(metric != null);
+    assert(metrics != null);
+    MetricGraphElement e = document.createElement(tag.name);
+    e._r = new RenderingScheduler(e, queue: queue);
+    e._isolate = isolate;
+    e._metric = metric;
+    e._metrics = metrics;
+    return e;
+  }
+
+  MetricGraphElement.created() : super.created();
+
+  @override
+  void attached() {
+    super.attached();
+    _r.enable();
+    _timer = new Timer.periodic(const Duration(seconds: 1), (_) => _r.dirty());
+  }
+
+  @override
+  void detached() {
+    super.detached();
+    _r.disable(notify: true);
+    children = [];
+    _timer.cancel();
+  }
+
+  final _columns = [
+      new ChartColumnSpec(label: 'Time', type: ChartColumnSpec.TYPE_TIMESTAMP),
+      new ChartColumnSpec(label: 'Value', formatter: (v) => v.toString())
+  ];
+
+  void render() {
+    final min = _metrics.getMinValue(_isolate, _metric);
+    final max = _metrics.getMaxValue(_isolate, _metric);
+    final rows = _metrics.getSamples(_isolate, _metric).map((s) =>
+      [s.time.millisecondsSinceEpoch, s.value]).toList();
+    final current = rows.last.last;
+
+    var message = 'current: $current';
+    if (min != null) {
+      message = 'min: $min, ' + message;
+    }
+    if (max != null) {
+      message = message + ', max: $max';
+    }
+
+    final host = new DivElement();
+    children = [
+      new DivElement()..classes = ['memberList']
+        ..children = [
+          new DivElement()..classes = ['memberItem']
+            ..children = min == null ? const [] : [
+              new DivElement()..classes = ['memberName']
+                ..text = 'min',
+              new DivElement()..classes = ['memberValue']
+                ..text = '$min'
+            ],
+          new DivElement()..classes = ['memberItem']
+            ..children = [
+              new DivElement()..classes = ['memberName']
+                ..text = 'current',
+              new DivElement()..classes = ['memberValue']
+                ..text = '$current'
+            ],
+          new DivElement()..classes = ['memberItem']
+            ..children = max == null ? const [] : [
+              new DivElement()..classes = ['memberName']
+                ..text = 'max',
+              new DivElement()..classes = ['memberValue']
+                ..text = '$max'
+            ]
+        ],
+      new DivElement()..classes = ['graph']
+        ..children = [
+          host
+        ]
+    ];
+    if (rows.length <= 1) {
+      return;
+    }
+    final rect = host.getBoundingClientRect();
+    var series = new ChartSeries("one", [1], new LineChartRenderer());
+    var config = new ChartConfig([series], [0]);
+    config.minimumSize = new Rect(rect.width, rect.height);
+    final data = new ChartData(_columns, rows);
+    new CartesianArea(host, data, config, state: new ChartState()).draw();
+  }
+}