Add initial version of analytics and crash reporting package.

pkg/telemetry/lib/crash_reporting.dart

Index: pkg/telemetry/lib/crash_reporting.dart
diff --git a/pkg/telemetry/lib/crash_reporting.dart b/pkg/telemetry/lib/crash_reporting.dart
new file mode 100644
index 0000000000000000000000000000000000000000..37d6b755949198f8ec031b7bb89affbb5441f16d
--- /dev/null
+++ b/pkg/telemetry/lib/crash_reporting.dart
@@ -0,0 +1,92 @@
+// Copyright (c) 2017, 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:async';
+import 'dart:io';
+
+import 'package:http/http.dart' as http;
+import 'package:stack_trace/stack_trace.dart';
+import 'package:usage/usage.dart';
+
+/// Crash backend host.
+const String _crashServerHost = 'clients2.google.com';
+
+/// Path to the crash servlet.
+const String _crashEndpointPath = '/cr/report'; // or, staging_report
+
+/// The field corresponding to the multipart/form-data file attachment where
+/// crash backend expects to find the Dart stack trace.
+const String _stackTraceFileField = 'DartError';
+
+/// The name of the file attached as [stackTraceFileField].
+///
+/// The precise value is not important. It is ignored by the crash back end, but
+/// it must be supplied in the request.
+const String _stackTraceFilename = 'stacktrace_file';
+
+/// Sends crash reports to Google.
+///
+/// Clients shouldn't extend, mixin or implement this class.
+class CrashReportSender {
+  static final Uri _baseUri = new Uri(
+      scheme: 'https', host: _crashServerHost, path: _crashEndpointPath);
+
+  final Analytics analytics;
+  final http.Client _httpClient;
+
+  /// Create a new [CrashReportSender], using the data from the given
+  /// [Analytics] instance.
+  CrashReportSender(this.analytics, {http.Client httpClient})
+      : _httpClient = httpClient ?? new http.Client();
+
+  /// Sends one crash report.
+  ///
+  /// The report is populated from data in [error] and [stackTrace].
+  Future sendReport(dynamic error, {StackTrace stackTrace}) async {
+    if (!analytics.enabled) {
+      return;
+    }
+
+    try {
+      final Uri uri = _baseUri.replace(
+        queryParameters: <String, String>{
+          'product': analytics.trackingId,
+          'version': analytics.applicationVersion,
+        },
+      );
+
+      final http.MultipartRequest req = new http.MultipartRequest('POST', uri);
+      req.fields['uuid'] = analytics.clientId;
+      req.fields['product'] = analytics.trackingId;
+      req.fields['version'] = analytics.applicationVersion;
+      req.fields['osName'] = Platform.operatingSystem;
+      // TODO(devoncarew): Report the operating system version when we're able.
+      //req.fields['osVersion'] = Platform.operatingSystemVersion;
+      req.fields['type'] = 'DartError';
+      req.fields['error_runtime_type'] = '${error.runtimeType}';
+
+      final Chain chain = new Chain.parse(stackTrace.toString());
+      req.files.add(new http.MultipartFile.fromString(
+          _stackTraceFileField, chain.terse.toString(),
+          filename: _stackTraceFilename));
+
+      final http.StreamedResponse resp = await _httpClient.send(req);
+
+      if (resp.statusCode != 200) {
+        throw 'server responded with HTTP status code ${resp.statusCode}';
+      }
+    } on SocketException catch (error) {
+      throw 'network error while sending crash report: $error';
+    } catch (error, stackTrace) {
+      // If the sender itself crashes, just print.
+      throw 'exception while sending crash report: $error\n$stackTrace';
+    }
+  }
+
+  /// Closes the client and cleans up any resources associated with it. This
+  /// will close the associated [http.Client].
+  void dispose() {
+    _httpClient.close();
+  }
+}