ref: Better handling of fingerprints (#1734)

Author: kamilogorek

CHANGELOG.md

@@ -3,6 +3,7 @@
 ## Unreleased
 
 - [core] feat: Filter internal Sentry errors from transports/sdk
+- [core] ref: Better fingerprint handling
 
 ## 4.3.0
 

packages/browser/src/backend.ts

@@ -112,7 +112,6 @@ export class BrowserBackend extends BaseBackend<BrowserOptions> {
   ): Promise<SentryEvent> {
     const event: SentryEvent = {
       event_id: hint && hint.event_id,
-      fingerprint: [message],
       level,
       message,
     };

packages/hub/src/scope.ts

@@ -172,6 +172,32 @@ export class Scope {
     this.notifyScopeListeners();
   }
 
+  /**
+   * Applies fingerprint from the scope to the event if there's one,
+   * uses message if there's one instead or get rid of empty fingerprint
+   */
+  private applyFingerprint(event: SentryEvent): void {
+    // Make sure it's an array first and we actually have something in place
+    event.fingerprint = event.fingerprint
+      ? Array.isArray(event.fingerprint)
+        ? event.fingerprint
+        : [event.fingerprint]
+      : [];
+
+    // If we have something on the scope, then merge it with event
+    if (this.fingerprint) {
+      event.fingerprint = event.fingerprint.concat(this.fingerprint);
+    } else if (event.message) {
+      // If not, but we have message, use it instead
+      event.fingerprint = event.fingerprint.concat(event.message);
+    }
+
+    // If we have no data at all, remove empty array default
+    if (event.fingerprint && !event.fingerprint.length) {
+      delete event.fingerprint;
+    }
+  }
+
   /**
    * Applies the current context and fingerprint to the event.
    * Note that breadcrumbs will be added by the client.
@@ -194,12 +220,12 @@ export class Scope {
     if (this.user && Object.keys(this.user).length) {
       event.user = { ...this.user, ...event.user };
     }
-    if (this.fingerprint && event.fingerprint === undefined) {
-      event.fingerprint = this.fingerprint;
-    }
     if (this.level) {
       event.level = this.level;
     }
+
+    this.applyFingerprint(event);
+
     const hasNoBreadcrumbs = !event.breadcrumbs || event.breadcrumbs.length === 0;
     if (hasNoBreadcrumbs && this.breadcrumbs.length > 0) {
       event.breadcrumbs =

packages/hub/test/scope.test.ts

@@ -122,10 +122,20 @@ describe('Scope', () => {
     expect(event.extra).toEqual({ a: 2, b: 3 });
     expect(event.tags).toEqual({ a: 'b', b: 'c' });
     expect(event.user).toEqual({ id: '3' });
-    expect(event.fingerprint).toEqual(['efgh']);
+    expect(event.fingerprint).toEqual(['efgh', 'abcd']);
     expect(event.breadcrumbs).toEqual([{ message: 'test2' }]);
   });
 
+  test('applyToEvent message fingerprint', async () => {
+    const scope = new Scope();
+    const event: SentryEvent = {
+      fingerprint: ['bar'],
+      message: 'foo',
+    };
+    await scope.applyToEvent(event);
+    expect(event.fingerprint).toEqual(['bar', 'foo']);
+  });
+
   test('applyToEvent scope level should be stronger', async () => {
     const scope = new Scope();
     scope.setLevel(Severity.Warning);

packages/node/src/backend.ts

@@ -68,7 +68,6 @@ export class NodeBackend extends BaseBackend<NodeOptions> {
   ): Promise<SentryEvent> {
     const event: SentryEvent = {
       event_id: hint && hint.event_id,
-      fingerprint: [message],
       level,
       message,
     };