feat(core): Add DSC to all outgoing envelopes

packages/core/src/scope.ts

@@ -482,9 +482,16 @@ export class Scope implements ScopeInterface {
     // errors with transaction and it relies on that.
     if (this._span) {
       event.contexts = { trace: this._span.getTraceContext(), ...event.contexts };
-      const transactionName = this._span.transaction && this._span.transaction.name;
-      if (transactionName) {
-        event.tags = { transaction: transactionName, ...event.tags };
+      const transaction = this._span.transaction;
+      if (transaction) {
+        event.sdkProcessingMetadata = {
+          ...event.sdkProcessingMetadata,
+          dynamicSamplingContext: transaction.getDynamicSamplingContext(),
+        };
+        const transactionName = transaction.name;
+        if (transactionName) {
+          event.tags = { transaction: transactionName, ...event.tags };
+        }
       }
     }
 

packages/core/test/lib/envelope.test.ts

@@ -6,12 +6,16 @@ const testDsn: DsnComponents = { protocol: 'https', projectId: 'abc', host: 'tes
 
 describe('createEventEnvelope', () => {
   describe('trace header', () => {
-    it("doesn't add trace header if event is not a transaction", () => {
-      const event: Event = {};
+    it('adds a trace header to error events', () => {
+      const event: Event = {
+        sdkProcessingMetadata: {
+          dynamicSamplingContext: { trace_id: '1234', public_key: 'pubKey123' },
+        },
+      };
       const envelopeHeaders = createEventEnvelope(event, testDsn)[0];
 
       expect(envelopeHeaders).toBeDefined();
-      expect(envelopeHeaders.trace).toBeUndefined();
+      expect(envelopeHeaders.trace).toBeDefined();
     });
 
     const testTable: Array<[string, Event, DynamicSamplingContext]> = [

packages/utils/src/envelope.ts

@@ -237,15 +237,13 @@ export function createEventEnvelopeHeaders(
   dsn: DsnComponents,
 ): EventEnvelopeHeaders {
   const dynamicSamplingContext = event.sdkProcessingMetadata && event.sdkProcessingMetadata.dynamicSamplingContext;
-
   return {
     event_id: event.event_id as string,
     sent_at: new Date().toISOString(),
     ...(sdkInfo && { sdk: sdkInfo }),
     ...(!!tunnel && { dsn: dsnToString(dsn) }),
-    ...(event.type === 'transaction' &&
-      dynamicSamplingContext && {
-        trace: dropUndefinedKeys({ ...dynamicSamplingContext }),
-      }),
+    ...(dynamicSamplingContext && {
+      trace: dropUndefinedKeys({ ...dynamicSamplingContext }),
+    }),
   };
 }