fix(apm): Add trace context to all events (#2486)

* fix: Add trace context to all events

* meta: Changelog

* meta: Add tests

CHANGELOG.md

@@ -7,6 +7,7 @@
 - [apm] feat: Add a simple heartbeat check, if activities don't change in 3 beats, finish the transaction (#2478)
 - [apm] feat: Make use of the `performance` browser API to provide better instrumentation (#2474)
 - [browser] ref: Move global error handler + unhandled promise rejection to instrument (#2475)
+- [apm] fix: Add trace context to all events (#2486)
 
 ## 5.13.2
 

packages/apm/src/span.ts

@@ -359,13 +359,13 @@ export class Span implements SpanInterface, SpanContext {
    */
   public getTraceContext(): object {
     return dropUndefinedKeys({
-      data: this.data,
+      data: Object.keys(this.data).length > 0 ? this.data : undefined,
       description: this.description,
       op: this.op,
       parent_span_id: this._parentSpanId,
       span_id: this._spanId,
       status: this.tags.status,
-      tags: this.tags,
+      tags: Object.keys(this.tags).length > 0 ? this.tags : undefined,
       trace_id: this._traceId,
     });
   }
@@ -375,14 +375,14 @@ export class Span implements SpanInterface, SpanContext {
    */
   public toJSON(): object {
     return dropUndefinedKeys({
-      data: this.data,
+      data: Object.keys(this.data).length > 0 ? this.data : undefined,
       description: this.description,
       op: this.op,
       parent_span_id: this._parentSpanId,
       sampled: this.sampled,
       span_id: this._spanId,
       start_timestamp: this.startTimestamp,
-      tags: this.tags,
+      tags: Object.keys(this.tags).length > 0 ? this.tags : undefined,
       timestamp: this.timestamp,
       trace_id: this._traceId,
       transaction: this.transaction,

packages/apm/test/span.test.ts

@@ -167,11 +167,9 @@ describe('Span', () => {
       expect(serialized).toHaveProperty('start_timestamp');
       delete (serialized as { start_timestamp: number }).start_timestamp;
       expect(serialized).toStrictEqual({
-        data: {},
         parent_span_id: 'b',
         sampled: false,
         span_id: 'd',
-        tags: {},
         trace_id: 'c',
       });
     });
@@ -257,9 +255,7 @@ describe('Span', () => {
       const spanB = new Span({ spanId: 'd', traceId: 'c' });
       const context = spanB.getTraceContext();
       expect(context).toStrictEqual({
-        data: {},
         span_id: 'd',
-        tags: {},
         trace_id: 'c',
       });
     });

packages/hub/src/scope.ts

@@ -332,6 +332,9 @@ export class Scope implements ScopeInterface {
     if (this._transaction) {
       event.transaction = this._transaction;
     }
+    if (this._span) {
+      event.contexts = { trace: this._span.getTraceContext(), ...event.contexts };
+    }
 
     this._applyFingerprint(event);
 

packages/hub/test/scope.test.ts

@@ -245,6 +245,38 @@ describe('Scope', () => {
     });
   });
 
+  test('applyToEvent trace context', async () => {
+    expect.assertions(1);
+    const scope = new Scope();
+    const span = {
+      fake: 'span',
+      getTraceContext: () => ({ a: 'b' }),
+    } as any;
+    scope.setSpan(span);
+    const event: Event = {};
+    return scope.applyToEvent(event).then(processedEvent => {
+      expect((processedEvent!.contexts!.trace as any).a).toEqual('b');
+    });
+  });
+
+  test('applyToEvent existing trace context in event should be stronger', async () => {
+    expect.assertions(1);
+    const scope = new Scope();
+    const span = {
+      fake: 'span',
+      getTraceContext: () => ({ a: 'b' }),
+    } as any;
+    scope.setSpan(span);
+    const event: Event = {
+      contexts: {
+        trace: { a: 'c' },
+      },
+    };
+    return scope.applyToEvent(event).then(processedEvent => {
+      expect((processedEvent!.contexts!.trace as any).a).toEqual('c');
+    });
+  });
+
   test('clear', () => {
     const scope = new Scope();
     scope.setExtra('a', 2);