feat: add BulkWriter (#323)

New BulkWriter leveraging [`BatchWriteRequest`](https://github.com/googleapis/googleapis/blob/393d03088e368d79c8f4cd5e3610c7df0bb118bf/google/firestore/v1/firestore.proto#L866-L881) which allows for fine grain batch processing of documents. Where as existing `WriteBatch` is an atomic write (all succeed or all fail). BulkWriter has been implemented to follow the 500/50/5 rule from [Firestore Best Practices: Ramping up traffic](https://firebase.google.com/docs/firestore/best-practices#ramping_up_traffic). If your application is already managing compliance with the 500/50/5 rule, you can configure the `BulkWriter` by using the `Firestore#bulkWriter(com.google.cloud.firestore.BulkWriterOptions)` method.

Author: Brian Chen

google-cloud-firestore/clirr-ignored-differences.xml

@@ -161,6 +161,44 @@
  <method>com.google.cloud.firestore.Query collectionGroup(java.lang.String)</method>
  <to>com.google.cloud.firestore.CollectionGroup</to>
  </difference>
+ 
+ <!--
+ BulkWriter
+ -->
+ <difference>
+ <differenceType>7012</differenceType>
+ <className>com/google/cloud/firestore/Firestore</className>
+ <method>com.google.cloud.firestore.BulkWriter bulkWriter(*)</method>
+ </difference>
+ <difference>
+ <differenceType>7006</differenceType>
+ <className>com/google/cloud/firestore/UpdateBuilder</className>
+ <method>com.google.cloud.firestore.UpdateBuilder create(*)</method>
+ <to>java.lang.Object</to>
+ </difference>
+ <difference>
+ <differenceType>7006</differenceType>
+ <className>com/google/cloud/firestore/UpdateBuilder</className>
+ <method>com.google.cloud.firestore.UpdateBuilder delete(*)</method>
+ <to>java.lang.Object</to>
+ </difference>
+ <difference>
+ <differenceType>7006</differenceType>
+ <className>com/google/cloud/firestore/UpdateBuilder</className>
+ <method>com.google.cloud.firestore.UpdateBuilder set(*)</method>
+ <to>java.lang.Object</to>
+ </difference>
+ <difference>
+ <differenceType>7006</differenceType>
+ <className>com/google/cloud/firestore/UpdateBuilder</className>
+ <method>com.google.cloud.firestore.UpdateBuilder update(*)</method>
+ <to>java.lang.Object</to>
+ </difference>
+ <difference>
+ <differenceType>7012</differenceType>
+ <className>com/google/cloud/firestore/spi/v1/FirestoreRpc</className>
+ <method>com.google.api.gax.rpc.UnaryCallable batchWriteCallable()</method>
+ </difference>
 
  <!--
  FakeCredentials Refactor

google-cloud-firestore/src/main/java/com/google/cloud/firestore/BatchWriteResult.java

@@ -0,0 +1,55 @@
+/*
+ * Copyright 2020 Google LLC
+ *
+ * Licensed 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 com.google.cloud.firestore;
+
+import com.google.api.core.InternalApi;
+import com.google.cloud.Timestamp;
+import javax.annotation.Nullable;
+
+/**
+ * A BatchWriteResult wraps the write time and status returned by Firestore when making
+ * BatchWriteRequests.
+ */
+@InternalApi
+public final class BatchWriteResult {
+ private final DocumentReference documentReference;
+ @Nullable private final Timestamp writeTime;
+ @Nullable private final Exception exception;
+
+ BatchWriteResult(
+ DocumentReference documentReference,
+ @Nullable Timestamp timestamp,
+ @Nullable Exception exception) {
+ this.documentReference = documentReference;
+ this.writeTime = timestamp;
+ this.exception = exception;
+ }
+
+ public DocumentReference getDocumentReference() {
+ return documentReference;
+ }
+
+ @Nullable
+ public Timestamp getWriteTime() {
+ return writeTime;
+ }
+
+ @Nullable
+ public Exception getException() {
+ return exception;
+ }
+}

google-cloud-firestore/src/main/java/com/google/cloud/firestore/BulkCommitBatch.java

@@ -0,0 +1,63 @@
+/*
+ * Copyright 2020 Google LLC
+ *
+ * Licensed 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 com.google.cloud.firestore;
+
+import com.google.api.core.ApiFuture;
+import com.google.common.base.Preconditions;
+import com.google.common.base.Predicate;
+import com.google.common.collect.FluentIterable;
+import java.util.Set;
+
+/** Used to represent a batch on the BatchQueue. */
+class BulkCommitBatch extends UpdateBuilder<ApiFuture<WriteResult>> {
+
+ BulkCommitBatch(FirestoreImpl firestore, int maxBatchSize) {
+ super(firestore, maxBatchSize);
+ }
+
+ BulkCommitBatch(
+ FirestoreImpl firestore,
+ BulkCommitBatch retryBatch,
+ final Set<DocumentReference> docsToRetry) {
+ super(firestore);
+ this.writes.addAll(
+ FluentIterable.from(retryBatch.writes)
+ .filter(
+ new Predicate<WriteOperation>() {
+ @Override
+ public boolean apply(WriteOperation writeOperation) {
+ return docsToRetry.contains(writeOperation.documentReference);
+ }
+ })
+ .toList());
+
+ Preconditions.checkState(
+ retryBatch.state == BatchState.SENT,
+ "Batch should be SENT when creating a new BulkCommitBatch for retry");
+ this.state = retryBatch.state;
+ this.pendingOperations = retryBatch.pendingOperations;
+ }
+
+ ApiFuture<WriteResult> wrapResult(ApiFuture<WriteResult> result) {
+ return result;
+ }
+
+ @Override
+ boolean allowDuplicateDocs() {
+ return false;
+ }
+}