| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.beam.sdk.io.gcp.pubsublite; |
| |
| import static com.google.cloud.pubsublite.cloudpubsub.MessageTransforms.fromCpsPublishTransformer; |
| import static com.google.cloud.pubsublite.cloudpubsub.MessageTransforms.toCpsPublishTransformer; |
| import static com.google.cloud.pubsublite.cloudpubsub.MessageTransforms.toCpsSubscribeTransformer; |
| |
| import com.google.cloud.pubsublite.Message; |
| import com.google.cloud.pubsublite.cloudpubsub.KeyExtractor; |
| import com.google.cloud.pubsublite.proto.PubSubMessage; |
| import com.google.cloud.pubsublite.proto.SequencedMessage; |
| import org.apache.beam.sdk.io.gcp.pubsub.PubsubMessage; |
| import org.apache.beam.sdk.io.gcp.pubsub.PubsubMessages; |
| import org.apache.beam.sdk.transforms.MapElements; |
| import org.apache.beam.sdk.transforms.PTransform; |
| import org.apache.beam.sdk.values.PCollection; |
| import org.apache.beam.sdk.values.TypeDescriptor; |
| |
| /** A class providing transforms between Cloud Pub/Sub and Pub/Sub Lite message types. */ |
| public final class CloudPubsubTransforms { |
| private CloudPubsubTransforms() {} |
| /** |
| * Ensure that all messages that pass through can be converted to Cloud Pub/Sub messages using the |
| * standard transformation methods in the client library. |
| * |
| * <p>Will fail the pipeline if a message has multiple attributes per key. |
| */ |
| public static PTransform<PCollection<PubSubMessage>, PCollection<PubSubMessage>> |
| ensureUsableAsCloudPubsub() { |
| return new PTransform<PCollection<PubSubMessage>, PCollection<PubSubMessage>>() { |
| @Override |
| public PCollection<PubSubMessage> expand(PCollection<PubSubMessage> input) { |
| return input.apply( |
| MapElements.into(TypeDescriptor.of(PubSubMessage.class)) |
| .via( |
| message -> { |
| Object unused = |
| toCpsPublishTransformer().transform(Message.fromProto(message)); |
| return message; |
| })); |
| } |
| }; |
| } |
| |
| /** |
| * Transform messages read from Pub/Sub Lite to their equivalent Cloud Pub/Sub Message that would |
| * have been read from PubsubIO. |
| * |
| * <p>Will fail the pipeline if a message has multiple attributes per map key. |
| */ |
| public static PTransform<PCollection<SequencedMessage>, PCollection<PubsubMessage>> |
| toCloudPubsubMessages() { |
| return new PTransform<PCollection<SequencedMessage>, PCollection<PubsubMessage>>() { |
| @Override |
| public PCollection<PubsubMessage> expand(PCollection<SequencedMessage> input) { |
| return input.apply( |
| MapElements.into(TypeDescriptor.of(PubsubMessage.class)) |
| .via( |
| message -> |
| PubsubMessages.fromProto( |
| toCpsSubscribeTransformer() |
| .transform( |
| com.google.cloud.pubsublite.SequencedMessage.fromProto( |
| message))))); |
| } |
| }; |
| } |
| |
| /** |
| * Transform messages publishable using PubsubIO to their equivalent Pub/Sub Lite publishable |
| * message. |
| */ |
| public static PTransform<PCollection<PubsubMessage>, PCollection<PubSubMessage>> |
| fromCloudPubsubMessages() { |
| return new PTransform<PCollection<PubsubMessage>, PCollection<PubSubMessage>>() { |
| @Override |
| public PCollection<PubSubMessage> expand(PCollection<PubsubMessage> input) { |
| return input.apply( |
| MapElements.into(TypeDescriptor.of(PubSubMessage.class)) |
| .via( |
| message -> |
| fromCpsPublishTransformer(KeyExtractor.DEFAULT) |
| .transform(PubsubMessages.toProto(message)) |
| .toProto())); |
| } |
| }; |
| } |
| } |