Bug fixes for cloud event conversion (GoogleCloudPlatform#85)

This commit fixes a few bugs in the code that converts legacy events to
cloud events:
- preserve nulls when serializing JSON
- firebaseauth and firebasedatabase event types
- firebaseauth subject is derived form user ID in event data
- fix code to extract firebasedatabase subject from resourceName

Author: matthewrobertson

.github/workflows/conformance.yaml

@@ -47,6 +47,5 @@ jobs:
       with:
         functionType: 'cloudevent'
         useBuildpacks: false
-        validateMapping: false
         cmd: "'mvn -f invoker/conformance/pom.xml function:run -Drun.functionTarget=com.google.cloud.functions.conformance.CloudEventsConformanceFunction'"
         startDelay: 10

invoker/conformance/pom.xml

@@ -42,6 +42,7 @@
         <plugin>
           <groupId>com.google.cloud.functions</groupId>
           <artifactId>function-maven-plugin</artifactId>
+          <version>0.9.8-SNAPSHOT</version>
         </plugin>
       </plugins>
     </pluginManagement>

invoker/core/src/main/java/com/google/cloud/functions/invoker/GcfEvents.java

@@ -21,6 +21,7 @@
 import com.google.cloud.functions.invoker.CloudFunctionsContext.Nullable;
 import com.google.cloud.functions.invoker.CloudFunctionsContext.Resource;
 import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
 import com.google.gson.JsonObject;
 import io.cloudevents.CloudEvent;
 import io.cloudevents.core.builder.CloudEventBuilder;
@@ -39,6 +40,8 @@
  */
 class GcfEvents {
   private static final String FIREBASE_SERVICE = "firebase.googleapis.com";
+  private static final String FIREBASE_AUTH_SERVICE = "firebaseauth.googleapis.com";
+  private static final String FIREBASE_DB_SERVICE = "firebasedatabase.googleapis.com";
   private static final String FIRESTORE_SERVICE = "firestore.googleapis.com";
   private static final String PUB_SUB_SERVICE = "pubsub.googleapis.com";
   private static final String STORAGE_SERVICE = "storage.googleapis.com";
@@ -71,25 +74,25 @@ class GcfEvents {
               FIRESTORE_SERVICE)),
 
       entry("providers/firebase.auth/eventTypes/user.create",
-          new FirestoreFirebaseEventAdapter("google.firebase.auth.user.v1.created", FIREBASE_SERVICE)),
+          new FirebaseAuthEventAdapter("google.firebase.auth.user.v1.created")),
       entry("providers/firebase.auth/eventTypes/user.delete",
-          new FirestoreFirebaseEventAdapter("google.firebase.auth.user.v1.deleted", FIREBASE_SERVICE)),
+          new FirebaseAuthEventAdapter("google.firebase.auth.user.v1.deleted")),
 
       entry("providers/google.firebase.analytics/eventTypes/event.log",
           new FirestoreFirebaseEventAdapter("google.firebase.analytics.log.v1.written", FIREBASE_SERVICE)),
 
       entry("providers/google.firebase.database/eventTypes/ref.create",
           new FirestoreFirebaseEventAdapter("google.firebase.database.document.v1.created",
-              FIREBASE_SERVICE)),
+              FIREBASE_DB_SERVICE)),
       entry("providers/google.firebase.database/eventTypes/ref.write",
           new FirestoreFirebaseEventAdapter("google.firebase.database.document.v1.written",
-              FIREBASE_SERVICE)),
+              FIREBASE_DB_SERVICE)),
       entry("providers/google.firebase.database/eventTypes/ref.update",
           new FirestoreFirebaseEventAdapter("google.firebase.database.document.v1.updated",
-              FIREBASE_SERVICE)),
+              FIREBASE_DB_SERVICE)),
       entry("providers/google.firebase.database/eventTypes/ref.delete",
           new FirestoreFirebaseEventAdapter("google.firebase.database.document.v1.deleted",
-              FIREBASE_SERVICE)),
+              FIREBASE_DB_SERVICE)),
 
       entry("providers/cloud.pubsub/eventTypes/topic.publish",
           new PubSubEventAdapter(PUB_SUB_MESSAGE_PUBLISHED)),
@@ -98,7 +101,7 @@ class GcfEvents {
           new StorageEventAdapter("google.cloud.storage.object.v1.changed"))
   );
 
-  private static final Gson GSON = new Gson();
+  private static final Gson GSON = new GsonBuilder().serializeNulls().create();
 
   static CloudEvent convertToCloudEvent(Event legacyEvent) {
     String eventType = legacyEvent.getContext().eventType();
@@ -135,7 +138,7 @@ final CloudEvent convertToCloudEvent(Event legacyEvent) {
       Resource resource = Resource.from(legacyEvent.getContext().resource());
       String service = Optional.ofNullable(resource.service()).orElse(defaultService);
       String resourceName = resource.name();
-      SourceAndSubject sourceAndSubject = convertResourceToSourceAndSubject(resourceName);
+      SourceAndSubject sourceAndSubject = convertResourceToSourceAndSubject(resourceName, legacyEvent);
       URI source = URI.create("//" + service + "/" + sourceAndSubject.source());
       OffsetDateTime timestamp =
           Optional.ofNullable(legacyEvent.getContext().timestamp())
@@ -156,7 +159,7 @@ String maybeReshapeData(Event legacyEvent, String jsonData) {
       return jsonData;
     }
 
-    SourceAndSubject convertResourceToSourceAndSubject(String resourceName) {
+    SourceAndSubject convertResourceToSourceAndSubject(String resourceName, Event legacyEvent) {
       return SourceAndSubject.of(resourceName, null);
     }
   }
@@ -184,32 +187,34 @@ private static class StorageEventAdapter extends EventAdapter {
     }
 
     @Override
-    SourceAndSubject convertResourceToSourceAndSubject(String resourceName) {
+    SourceAndSubject convertResourceToSourceAndSubject(String resourceName, Event legacyEvent) {
       Matcher matcher = STORAGE_RESOURCE_PATTERN.matcher(resourceName);
       if (matcher.matches()) {
         String resource = matcher.group(1);
         String subject = matcher.group(2);
         return SourceAndSubject.of(resource, subject);
       }
-      return super.convertResourceToSourceAndSubject(resourceName);
+      return super.convertResourceToSourceAndSubject(resourceName, legacyEvent);
     }
   }
 
   private static class FirestoreFirebaseEventAdapter extends EventAdapter {
+    private static final Pattern FIRESTORE_RESOURCE_PATTERN =
+        Pattern.compile("^(projects/.+)/((documents|refs)/.+)$");
+
     FirestoreFirebaseEventAdapter(String cloudEventType, String defaultService) {
       super(cloudEventType, defaultService);
     }
 
     @Override
-    SourceAndSubject convertResourceToSourceAndSubject(String resourceName) {
-      List<String> resourceSegments = Arrays.asList(resourceName.split("/"));
-      int documentsIndex = resourceSegments.indexOf("documents");
-      if (documentsIndex < 0) {
-        return super.convertResourceToSourceAndSubject(resourceName);
+    SourceAndSubject convertResourceToSourceAndSubject(String resourceName, Event legacyEvent) {
+      Matcher matcher = FIRESTORE_RESOURCE_PATTERN.matcher(resourceName);
+      if (matcher.matches()) {
+        String resource = matcher.group(1);
+        String subject = matcher.group(2);
+        return SourceAndSubject.of(resource, subject);
       }
-      String sourcePath = String.join("/", resourceSegments.subList(0, documentsIndex));
-      String subject = String.join("/", resourceSegments.subList(documentsIndex, resourceSegments.size()));
-      return SourceAndSubject.of(sourcePath, subject);
+      return super.convertResourceToSourceAndSubject(resourceName, legacyEvent);
     }
 
     @Override
@@ -226,4 +231,38 @@ String maybeReshapeData(Event legacyEvent, String jsonData) {
       return GSON.toJson(jsonObject);
     }
   }
+
+  private static class FirebaseAuthEventAdapter extends EventAdapter {
+    FirebaseAuthEventAdapter(String cloudEventType) {
+      super(cloudEventType, FIREBASE_AUTH_SERVICE);
+    }
+
+    @Override
+    SourceAndSubject convertResourceToSourceAndSubject(String resourceName, Event legacyEvent) {
+      String subject = null;
+      JsonObject data = legacyEvent.getData().getAsJsonObject();
+      if (data.has("uid")) {
+        subject = "users/" + data.get("uid").getAsString();
+      }
+      return SourceAndSubject.of(resourceName, subject);
+    }
+
+    @Override
+    String maybeReshapeData(Event legacyEvent, String jsonData) {
+      JsonObject jsonObject = GSON.fromJson(jsonData, JsonObject.class);
+      if (!jsonObject.has("metadata")) {
+        return jsonData;
+      }
+      JsonObject metadata = jsonObject.getAsJsonObject("metadata");
+      if (metadata.has("createdAt")) {
+        metadata.add("createTime", metadata.get("createdAt"));
+        metadata.remove("createdAt");
+      }
+      if (metadata.has("lastSignedInAt")) {
+        metadata.add("lastSignInTime", metadata.get("lastSignedInAt"));
+        metadata.remove("lastSignedInAt");
+      }
+      return GSON.toJson(jsonObject);
+    }
+  }
 }

invoker/core/src/test/java/com/google/cloud/functions/invoker/GcfEventsTest.java

@@ -29,6 +29,7 @@
 import java.time.OffsetDateTime;
 import java.time.ZoneOffset;
 import java.util.Base64;
+import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import org.junit.Ignore;
@@ -51,11 +52,11 @@ public class GcfEventsTest {
     {"legacy_pubsub.json", "google.cloud.pubsub.topic.v1.messagePublished",
       "//pubsub.googleapis.com/projects/sample-project/topics/gcf-test", null},
     {"firebase-db1.json", "google.firebase.database.document.v1.written",
-      "//firebase.googleapis.com/projects/_/instances/my-project-id/refs/gcf-test/xyz", null},
+      "//firebasedatabase.googleapis.com/projects/_/instances/my-project-id", "refs/gcf-test/xyz"},
     {"firebase-auth1.json", "google.firebase.auth.user.v1.created",
-      "//firebase.googleapis.com/projects/my-project-id", null},
+      "//firebaseauth.googleapis.com/projects/my-project-id", "users/UUpby3s4spZre6kHsgVSPetzQ8l2"},
     {"firebase-auth2.json", "google.firebase.auth.user.v1.deleted",
-      "//firebase.googleapis.com/projects/my-project-id", null},
+      "//firebaseauth.googleapis.com/projects/my-project-id", "users/UUpby3s4spZre6kHsgVSPetzQ8l2"},
   };
 
   @Test
@@ -152,7 +153,7 @@ public void firestoreComplexData() throws IOException {
         "geoPointValue", Map.of("geoPointValue", Map.of("latitude", 51.4543, "longitude", -0.9781)),
         "intValue", Map.of("integerValue", "50"),
         "doubleValue", Map.of("doubleValue", 5.5),
-        "nullValue", Map.of(),
+        "nullValue", Collections.singletonMap("nullValue", null),
         "referenceValue", Map.of("referenceValue",
             "projects/project-id/databases/(default)/documents/foo/bar/baz/qux"),
         "stringValue", Map.of("stringValue", "text"),