Ensure usr.exists tag is not overridden by auto instrumentation (#8374)

Author: manuel-alvarez-alvarez

dd-java-agent/appsec/src/main/java/com/datadog/appsec/gateway/GatewayBridge.java

@@ -279,9 +279,6 @@ private Flow<Void> onLoginEvent(
 
     // update span tags
     segment.setTagTop("appsec.events." + eventName + ".track", true, true);
-    if (exists != null) {
-      segment.setTagTop("appsec.events." + eventName + ".usr.exists", exists, true);
-    }
     if (metadata != null && !metadata.isEmpty()) {
       segment.setTagTop("appsec.events." + eventName, metadata, true);
     }
@@ -315,6 +312,10 @@ private Flow<Void> onLoginEvent(
       segment.setTagTop("_dd.appsec.user.collection_mode", mode.fullName());
     }
 
+    if (exists != null) {
+      segment.setTagTop("appsec.events." + eventName + ".usr.exists", exists, true);
+    }
+
     // update user span tags
     segment.setTagTop("appsec.events." + eventName + ".usr.login", user, true);
 

dd-java-agent/appsec/src/test/groovy/com/datadog/appsec/gateway/GatewayBridgeSpecification.groovy

@@ -1285,6 +1285,41 @@ class GatewayBridgeSpecification extends DDSpecification {
     0 * eventDispatcher.publishDataEvent
   }
 
+  void "test onLoginFailure (automated login events should not overwrite SDK)"() {
+    setup:
+    final firstUser = 'user1'
+    final secondUser = 'user2'
+    eventDispatcher.getDataSubscribers(_) >> nonEmptyDsInfo
+
+    when:
+    loginEventCB.apply(ctx, SDK, 'users.login.failure', true, firstUser, null)
+
+    then:
+    1 * traceSegment.setTagTop('appsec.events.users.login.failure.usr.login', firstUser, true)
+    1 * traceSegment.setTagTop('_dd.appsec.events.users.login.failure.sdk', true, true)
+    1 * traceSegment.setTagTop('_dd.appsec.user.collection_mode', 'sdk')
+    1 * traceSegment.setTagTop('appsec.events.users.login.failure.usr.exists', true, true)
+
+    0 * traceSegment.setTagTop('_dd.appsec.usr.login', _)
+    0 * traceSegment.setTagTop('_dd.appsec.events.users.login.failure.auto.mode', _, _)
+
+    1 * eventDispatcher.publishDataEvent(nonEmptyDsInfo, ctx.data, _ as DataBundle, _ as GatewayContext) >> NoopFlow.INSTANCE
+
+    when:
+    loginEventCB.apply(ctx, IDENTIFICATION, 'users.login.failure', false, secondUser, null)
+
+    then:
+    0 * traceSegment.setTagTop('appsec.events.users.login.failure.usr.login', _, _)
+    0 * traceSegment.setTagTop('_dd.appsec.events.users.login.failure.sdk', _, _)
+    0 * traceSegment.setTagTop('_dd.appsec.user.collection_mode', _)
+    0 * traceSegment.setTagTop('appsec.events.users.login.failure.usr.exists', _, _)
+
+    1 * traceSegment.setTagTop('_dd.appsec.usr.login', secondUser)
+    1 * traceSegment.setTagTop('_dd.appsec.events.users.login.failure.auto.mode', IDENTIFICATION.fullName(), true)
+
+    0 * eventDispatcher.publishDataEvent
+  }
+
   void 'test configuration updates should reset cached subscriptions'() {
     when:
     requestSessionCB.apply(ctx, UUID.randomUUID().toString())