Update CloudEvent upcasting logic (GoogleCloudPlatform#99)

Author: matthewrobertson

.github/workflows/conformance.yaml

@@ -55,6 +55,6 @@ jobs:
       with:
         functionType: 'cloudevent'
         useBuildpacks: false
-        validateMapping: false
+        validateMapping: true
         cmd: "'mvn -f invoker/conformance/pom.xml function:run -Drun.functionTarget=com.google.cloud.functions.conformance.CloudEventsConformanceFunction'"
         startDelay: 10

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

@@ -50,6 +50,9 @@ abstract class CloudFunctionsContext implements Context {
   // TODO: expose this in the Context interface (as a default method).
   abstract Map<String, String> params();
 
+  @Nullable
+  abstract String domain();
+
   @Override
   public abstract Map<String, String> attributes();
 
@@ -71,6 +74,7 @@ abstract static class Builder {
     abstract Builder setResource(String x);
     abstract Builder setParams(Map<String, String> x);
     abstract Builder setAttributes(Map<String, String> value);
+    abstract Builder setDomain(String x);
 
     abstract CloudFunctionsContext build();
   }

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

@@ -82,17 +82,13 @@ class GcfEvents {
           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_DB_SERVICE)),
+          new FirebaseDatabaseEventAdapter("google.firebase.database.document.v1.created")),
       entry("providers/google.firebase.database/eventTypes/ref.write",
-          new FirestoreFirebaseEventAdapter("google.firebase.database.document.v1.written",
-              FIREBASE_DB_SERVICE)),
+          new FirebaseDatabaseEventAdapter("google.firebase.database.document.v1.written")),
       entry("providers/google.firebase.database/eventTypes/ref.update",
-          new FirestoreFirebaseEventAdapter("google.firebase.database.document.v1.updated",
-              FIREBASE_DB_SERVICE)),
+          new FirebaseDatabaseEventAdapter("google.firebase.database.document.v1.updated")),
       entry("providers/google.firebase.database/eventTypes/ref.delete",
-          new FirestoreFirebaseEventAdapter("google.firebase.database.document.v1.deleted",
-              FIREBASE_DB_SERVICE)),
+          new FirebaseDatabaseEventAdapter("google.firebase.database.document.v1.deleted")),
 
       entry("providers/cloud.pubsub/eventTypes/topic.publish",
           new PubSubEventAdapter(PUB_SUB_MESSAGE_PUBLISHED)),
@@ -172,6 +168,8 @@ private static class PubSubEventAdapter extends EventAdapter {
     @Override
     String maybeReshapeData(Event legacyEvent, String jsonData) {
       JsonObject jsonObject = GSON.fromJson(jsonData, JsonObject.class);
+      jsonObject.addProperty("messageId", legacyEvent.getContext().eventId());
+      jsonObject.addProperty("publishTime", legacyEvent.getContext().timestamp());
       JsonObject wrapped = new JsonObject();
       wrapped.add("message", jsonObject);
       return GSON.toJson(wrapped);
@@ -232,6 +230,44 @@ String maybeReshapeData(Event legacyEvent, String jsonData) {
     }
   }
 
+  private static class FirebaseDatabaseEventAdapter extends EventAdapter {
+    private static final Pattern FIREBASE_DB_RESOURCE_PATTERN =
+        Pattern.compile("^projects/_/(instances/[^/]+)/((documents|refs)/.+)$");
+
+    FirebaseDatabaseEventAdapter(String cloudEventType) {
+      super(cloudEventType, FIREBASE_DB_SERVICE);
+    }
+
+    @Override
+    SourceAndSubject convertResourceToSourceAndSubject(String resourceName, Event legacyEvent) {
+      Matcher matcher = FIREBASE_DB_RESOURCE_PATTERN.matcher(resourceName);
+      String location = parseLocation(legacyEvent);
+      if (matcher.matches() && location != null) {
+        String resource = String.format("projects/_/locations/%s/%s", location, matcher.group(1));
+        String subject = matcher.group(2);
+        return SourceAndSubject.of(resource, subject);
+      }
+      return super.convertResourceToSourceAndSubject(resourceName, legacyEvent);
+    }
+
+    private String parseLocation(Event legacyEvent) {
+      String domain = legacyEvent.getContext().domain();
+      if (domain == null) {
+        return null;
+      }
+      // The default location for firebaseio.com is us-central1
+      if ("firebaseio.com".equals(domain)) {
+        return "us-central1";
+      }
+      // Otherwise the location can be inferred from the first subdomain
+      String[] subdomains = domain.split("\\.");
+      if (subdomains.length > 1) {
+        return subdomains[0];
+      }
+      return null;
+    }
+  }
+
   private static class FirebaseAuthEventAdapter extends EventAdapter {
     FirebaseAuthEventAdapter(String cloudEventType) {
       super(cloudEventType, FIREBASE_AUTH_SERVICE);

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

@@ -52,7 +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",
-      "//firebasedatabase.googleapis.com/projects/_/instances/my-project-id", "refs/gcf-test/xyz"},
+      "//firebasedatabase.googleapis.com/projects/_/locations/us-central1/instances/my-project-id",
+      "refs/gcf-test/xyz"},
+    {"firebase-db2.json", "google.firebase.database.document.v1.written",
+      "//firebasedatabase.googleapis.com/projects/_/locations/europe-west1/instances/my-project-id",
+      "refs/gcf-test/xyz"},
     {"firebase-auth1.json", "google.firebase.auth.user.v1.created",
       "//firebaseauth.googleapis.com/projects/my-project-id", "users/UUpby3s4spZre6kHsgVSPetzQ8l2"},
     {"firebase-auth2.json", "google.firebase.auth.user.v1.deleted",
@@ -211,7 +215,9 @@ public void pubSubWrapping() throws IOException {
     assertThat(new String(cloudEvent.getData().toBytes(), UTF_8))
         .isEqualTo("{\"message\":{\"@type\":\"type.googleapis.com/google.pubsub.v1.PubsubMessage\","
             + "\"attributes\":{\"attribute1\":\"value1\"},"
-            + "\"data\":\"VGhpcyBpcyBhIHNhbXBsZSBtZXNzYWdl\"}}");
+            + "\"data\":\"VGhpcyBpcyBhIHNhbXBsZSBtZXNzYWdl\","
+            + "\"messageId\":\"1215011316659232\","
+            + "\"publishTime\":\"2020-05-18T12:13:19.209Z\"}}");
   }
 
   // Checks that a Firestore event correctly gets an extra "wildcards" property in its CloudEvent data

invoker/core/src/test/resources/firebase-db1.json

@@ -6,6 +6,7 @@
   "auth": {
     "admin": true
   },
+  "domain": "firebaseio.com",
   "data": {
     "data": null,
     "delta": {

invoker/core/src/test/resources/firebase-db2.json

@@ -0,0 +1,21 @@
+{
+  "eventType": "providers/google.firebase.database/eventTypes/ref.write",
+  "params": {
+    "child": "xyz"
+  },
+  "auth": {
+    "admin": true
+  },
+  "domain":"europe-west1.firebasedatabase.app",
+  "data": {
+    "data": {
+      "grandchild": "other"
+    },
+    "delta": {
+      "grandchild": "other changed"
+    }
+  },
+  "resource": "projects/_/instances/my-project-id/refs/gcf-test/xyz",
+  "timestamp": "2020-09-29T11:32:00.000Z",
+  "eventId": "aaaaaa-1111-bbbb-2222-cccccccccccc"
+}