Feat: Sentry Performance for HTTP client

CHANGELOG.md

@@ -3,7 +3,8 @@
 * Bump Sentry Android SDK to [5.2.0](https://github.com/getsentry/sentry-dart/pull/594) (#594)
   - [changelog](https://github.com/getsentry/sentry-java/blob/5.2.0/CHANGELOG.md)
   - [diff](https://github.com/getsentry/sentry-java/compare/5.1.2...5.2.0)
-* enrich Dart context with isolate name (#600)
+* Feat: Enrich Dart context with isolate name (#600)
+* Feat: Sentry Performance for HTTP client (#603)
 
 # 6.1.0-alpha.1
 

dart/lib/src/http_client/breadcrumb_client.dart

@@ -91,8 +91,5 @@ class BreadcrumbClient extends BaseClient {
   }
 
   @override
-  void close() {
-    // See https://github.com/getsentry/sentry-dart/pull/226#discussion_r536984785
-    _client.close();
-  }
+  void close() => _client.close();
 }

dart/lib/src/http_client/failed_request_client.dart

@@ -143,10 +143,7 @@ class FailedRequestClient extends BaseClient {
   }
 
   @override
-  void close() {
-    // See https://github.com/getsentry/sentry-dart/pull/226#discussion_r536984785
-    _client.close();
-  }
+  void close() => _client.close();
 
   // See https://develop.sentry.dev/sdk/event-payloads/request/
   Future<void> _captureEvent({

dart/lib/src/http_client/sentry_http_client.dart

@@ -1,4 +1,5 @@
 import 'package:http/http.dart';
+import 'tracing_client.dart';
 import '../hub.dart';
 import '../hub_adapter.dart';
 import '../protocol.dart';
@@ -7,9 +8,9 @@ import 'failed_request_client.dart';
 
 /// A [http](https://pub.dev/packages/http)-package compatible HTTP client.
 ///
-/// It can record requests as breadcrumbs. This is on by default.
+/// It records requests as breadcrumbs. This is on by default.
 ///
-/// It can also capture requests which throw an exception. This is off by
+/// It captures requests which throws an exception. This is off by
 /// default, set [captureFailedRequests] to `true` to enable it. This can be for
 /// example for the following reasons:
 /// - In an browser environment this can be requests which fail because of CORS.
@@ -32,6 +33,10 @@ import 'failed_request_client.dart';
 /// );
 /// ```
 ///
+/// It starts and finishes a Span if there's a transaction bound to the Scope
+/// through the [TracingClient] client, it's disabled by default.
+/// Set [networkTracing] to `true` to enable it.
+///
 /// Remarks: If this client is used as a wrapper, a call to close also closes
 /// the given client.
 ///
@@ -79,6 +84,7 @@ class SentryHttpClient extends BaseClient {
     List<SentryStatusCode> failedRequestStatusCodes = const [],
     bool captureFailedRequests = false,
     bool sendDefaultPii = false,
+    bool networkTracing = false,
   }) {
     _hub = hub ?? HubAdapter();
 
@@ -93,6 +99,10 @@ class SentryHttpClient extends BaseClient {
       client: innerClient,
     );
 
+    if (networkTracing) {
+      innerClient = TracingClient(client: innerClient, hub: _hub);
+    }
+
     // The ordering here matters.
     // We don't want to include the breadcrumbs for the current request
     // when capturing it as a failed request.
@@ -110,6 +120,7 @@ class SentryHttpClient extends BaseClient {
   @override
   Future<StreamedResponse> send(BaseRequest request) => _client.send(request);
 
+  // See https://github.com/getsentry/sentry-dart/pull/226#discussion_r536984785
   @override
   void close() => _client.close();
 }

dart/lib/src/http_client/tracing_client.dart

@@ -0,0 +1,50 @@
+import 'package:http/http.dart';
+import '../hub.dart';
+import '../hub_adapter.dart';
+import '../protocol.dart';
+
+/// A [http](https://pub.dev/packages/http)-package compatible HTTP client
+/// which adds support to Sentry Performance feature.
+/// https://develop.sentry.dev/sdk/performance
+class TracingClient extends BaseClient {
+  TracingClient({Client? client, Hub? hub})
+      : _hub = hub ?? HubAdapter(),
+        _client = client ?? Client();
+
+  final Client _client;
+  final Hub _hub;
+
+  @override
+  Future<StreamedResponse> send(BaseRequest request) async {
+    // see https://develop.sentry.dev/sdk/performance/#header-sentry-trace
+    final currentSpan = _hub.getSpan();
+    final span = currentSpan?.startChild(
+      'http.client',
+      description: '${request.method} ${request.url}',
+    );
+
+    StreamedResponse? response;
+    try {
+      if (span != null) {
+        final traceHeader = span.toSentryTrace();
+        request.headers[traceHeader.name] = traceHeader.value;
+      }
+
+      // TODO: tracingOrigins support
+
+      response = await _client.send(request);
+      span?.status = SpanStatus.fromHttpStatusCode(response.statusCode);
+    } catch (exception) {
+      span?.throwable = exception;
+      span?.status = SpanStatus.internalError();
+
+      rethrow;
+    } finally {
+      await span?.finish();
+    }
+    return response;
+  }
+
+  @override
+  void close() => _client.close();
+}

dart/lib/src/hub.dart

@@ -400,6 +400,11 @@ class Hub {
         SentryLevel.warning,
         "Instance is disabled and this 'getSpan' call is a no-op.",
       );
+    } else if (!_options.isTracingEnabled()) {
+      _options.logger(
+        SentryLevel.info,
+        "Tracing is disabled and this 'getSpan' returns null.",
+      );
     } else {
       final item = _peek();
 
@@ -418,6 +423,11 @@ class Hub {
         SentryLevel.warning,
         "Instance is disabled and this 'captureTransaction' call is a no-op.",
       );
+    } else if (!_options.isTracingEnabled()) {
+      _options.logger(
+        SentryLevel.info,
+        "Tracing is disabled and this 'captureTransaction' call is a no-op.",
+      );
     } else if (!transaction.finished) {
       _options.logger(
         SentryLevel.warning,

dart/lib/src/invalid_sentry_trace_header_exception.dart

@@ -0,0 +1,7 @@
+class InvalidSentryTraceHeaderException implements Exception {
+  final String _message;
+  InvalidSentryTraceHeaderException(this._message);
+
+  @override
+  String toString() => 'Exception: $_message';
+}

dart/lib/src/noop_sentry_span.dart

@@ -13,6 +13,12 @@ class NoOpSentrySpan extends ISentrySpan {
     operation: 'noop',
   );
 
+  static final _header = SentryTraceHeader(
+    SentryId.empty(),
+    SpanId.empty(),
+    sampled: false,
+  );
+
   static final _timestamp = getUtcDateTime();
 
   factory NoOpSentrySpan() {
@@ -64,4 +70,7 @@ class NoOpSentrySpan extends ISentrySpan {
 
   @override
   bool? get sampled => null;
+
+  @override
+  SentryTraceHeader toSentryTrace() => _header;
 }

dart/lib/src/protocol.dart

@@ -32,3 +32,4 @@ export 'protocol/span_id.dart';
 export 'protocol/sentry_transaction.dart';
 export 'protocol/sentry_trace_context.dart';
 export 'protocol/sentry_span.dart';
+export 'protocol/sentry_trace_header.dart';

dart/lib/src/protocol/sentry_span.dart

@@ -1,5 +1,5 @@
 import '../hub.dart';
-import 'span_status.dart';
+import '../protocol.dart';
 
 import '../sentry_tracer.dart';
 import '../tracing.dart';
@@ -121,4 +121,11 @@ class SentrySpan extends ISentrySpan {
   Map<String, String> get tags => _tags;
 
   Map<String, dynamic> get data => _data;
+
+  @override
+  SentryTraceHeader toSentryTrace() => SentryTraceHeader(
+        _context.traceId,
+        _context.spanId,
+        sampled: sampled,
+      );
 }

dart/lib/src/protocol/sentry_trace_header.dart

@@ -0,0 +1,51 @@
+import 'package:meta/meta.dart';
+
+import '../invalid_sentry_trace_header_exception.dart';
+import '../protocol.dart';
+
+/// Represents HTTP header "sentry-trace".
+@immutable
+class SentryTraceHeader {
+  static const _traceHeader = 'sentry-trace';
+
+  final SentryId traceId;
+  final SpanId spanId;
+  final bool? sampled;
+
+  String get name => _traceHeader;
+
+  String get value {
+    if (sampled != null) {
+      final sampled = this.sampled! ? '1' : '0';
+      return '$traceId-$spanId-$sampled';
+    } else {
+      return '$traceId-$spanId';
+    }
+  }
+
+  SentryTraceHeader(
+    this.traceId,
+    this.spanId, {
+    bool? sampled,
+  }) : sampled = sampled;
+
+  factory SentryTraceHeader.fromTraceHeader(String header) {
+    final parts = header.split('-');
+    bool? sampled;
+
+    if (parts.length < 2) {
+      throw InvalidSentryTraceHeaderException('Header: $header is invalid.');
+    } else if (parts.length == 3) {
+      sampled = '1' == parts[2];
+    }
+
+    final traceId = SentryId.fromId(parts[0]);
+    final spanId = SpanId.fromId(parts[1]);
+
+    return SentryTraceHeader(
+      traceId,
+      spanId,
+      sampled: sampled,
+    );
+  }
+}

dart/lib/src/sentry.dart

@@ -251,8 +251,6 @@ class Sentry {
         bindToScope: bindToScope,
       );
 
-  // missing traceHeaders
-
   /// Gets the current active transaction or span.
   static ISentrySpan? getSpan() => _hub.getSpan();
 

dart/lib/src/sentry_span_interface.dart

@@ -1,6 +1,6 @@
 import 'package:meta/meta.dart';
 
-import 'protocol/span_status.dart';
+import 'protocol.dart';
 import 'tracing.dart';
 
 /// Represents performance monitoring Span.
@@ -42,7 +42,6 @@ abstract class ISentrySpan {
 
   /// Returns the star timestamp
   DateTime get startTimestamp;
-  // missing toTraceHeader
 
   /// Returns true if span is finished
   bool get finished;
@@ -55,4 +54,7 @@ abstract class ISentrySpan {
 
   @internal
   bool? get sampled;
+
+  /// Returns the trace information that could be sent as a sentry-trace header.
+  SentryTraceHeader toSentryTrace();
 }

dart/lib/src/sentry_tracer.dart

@@ -132,4 +132,7 @@ class SentryTracer extends ISentrySpan {
 
   @override
   bool? get sampled => _rootSpan.sampled;
+
+  @override
+  SentryTraceHeader toSentryTrace() => _rootSpan.toSentryTrace();
 }

dart/lib/src/sentry_transaction_context.dart

@@ -26,6 +26,20 @@ class SentryTransactionContext extends SentrySpanContext {
           parentSpanId: parentSpanId,
         );
 
+  factory SentryTransactionContext.fromSentryTrace(
+    String name,
+    String operation,
+    SentryTraceHeader traceHeader,
+  ) {
+    return SentryTransactionContext(
+      name,
+      operation,
+      traceId: traceHeader.traceId,
+      parentSpanId: traceHeader.spanId,
+      parentSampled: traceHeader.sampled,
+    );
+  }
+
   SentryTransactionContext copyWith({
     String? name,
     String? operation,

dart/lib/src/tracing.dart

@@ -3,3 +3,4 @@ export 'sentry_sampling_context.dart';
 export 'sentry_span_context.dart';
 export 'sentry_span_interface.dart';
 export 'noop_sentry_span.dart';
+export 'invalid_sentry_trace_header_exception.dart';

dart/test/http_client/sentry_http_client_test.dart

@@ -73,6 +73,32 @@ void main() {
       expect(mockHub.captureExceptionCalls.length, 0);
       verify(mockClient.close());
     });
+
+    test('no captured span if tracing disabled', () async {
+      final sut = fixture.getSut(
+        client: fixture.getClient(statusCode: 200, reason: 'OK'),
+        recordBreadcrumbs: false,
+        networkTracing: false,
+      );
+
+      final response = await sut.get(requestUri);
+      expect(response.statusCode, 200);
+
+      expect(fixture.hub.getSpanCalls, 0);
+    });
+
+    test('captured span if tracing enabled', () async {
+      final sut = fixture.getSut(
+        client: fixture.getClient(statusCode: 200, reason: 'OK'),
+        recordBreadcrumbs: false,
+        networkTracing: true,
+      );
+
+      final response = await sut.get(requestUri);
+      expect(response.statusCode, 200);
+
+      expect(fixture.hub.getSpanCalls, 1);
+    });
   });
 }
 
@@ -94,6 +120,7 @@ class Fixture {
     MaxRequestBodySize maxRequestBodySize = MaxRequestBodySize.never,
     List<SentryStatusCode> badStatusCodes = const [],
     bool recordBreadcrumbs = true,
+    bool networkTracing = false,
   }) {
     final mc = client ?? getClient();
     return SentryHttpClient(
@@ -103,6 +130,7 @@ class Fixture {
       failedRequestStatusCodes: badStatusCodes,
       maxRequestBodySize: maxRequestBodySize,
       recordBreadcrumbs: recordBreadcrumbs,
+      networkTracing: networkTracing,
     );
   }