com.facebook.buck.remoteexecution.grpc.GrpcAsyncBlobFetcher.java Source code

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Here is the source code for com.facebook.buck.remoteexecution.grpc.GrpcAsyncBlobFetcher.java

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/*
 * Copyright 2018-present Facebook, Inc.
 *
 * 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.facebook.buck.remoteexecution.grpc;

import com.facebook.buck.event.BuckEventBus;
import com.facebook.buck.remoteexecution.AsyncBlobFetcher;
import com.facebook.buck.remoteexecution.event.CasBlobDownloadEvent;
import com.facebook.buck.remoteexecution.interfaces.Protocol;
import com.facebook.buck.remoteexecution.proto.RemoteExecutionMetadata;
import com.facebook.buck.util.Scope;
import com.google.bytestream.ByteStreamGrpc.ByteStreamStub;
import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListenableFuture;
import com.google.common.util.concurrent.MoreExecutors;
import com.google.protobuf.ByteString;
import java.io.OutputStream;
import java.nio.ByteBuffer;

/** GRPC implementation of the AsyncBlobFetcher. */
public class GrpcAsyncBlobFetcher implements AsyncBlobFetcher {

    private final String instanceName;
    private final ByteStreamStub byteStreamStub;
    private final BuckEventBus buckEventBus;

    public GrpcAsyncBlobFetcher(String instanceName, ByteStreamStub byteStreamStub, BuckEventBus buckEventBus,
            RemoteExecutionMetadata metadata) {
        this.instanceName = instanceName;
        this.byteStreamStub = GrpcHeaderHandler.wrapStubToSendMetadata(byteStreamStub, metadata);
        this.buckEventBus = buckEventBus;
    }

    @Override
    public ListenableFuture<ByteBuffer> fetch(Protocol.Digest digest) {
        /** Payload received on a fetch request. */
        class Data {
            ByteString data = ByteString.EMPTY;

            public ByteBuffer get() {
                return data.asReadOnlyByteBuffer();
            }

            public void concat(ByteString bytes) {
                data = data.concat(bytes);
            }
        }

        Data data = new Data();
        return closeScopeWhenFutureCompletes(CasBlobDownloadEvent.sendEvent(buckEventBus, 1, digest.getSize()),
                Futures.transform(GrpcRemoteExecutionClients.readByteStream(instanceName, digest, byteStreamStub,
                        data::concat), ignored -> data.get(), MoreExecutors.directExecutor()));
    }

    @Override
    public ListenableFuture<Void> fetchToStream(Protocol.Digest digest, OutputStream outputStream) {
        return closeScopeWhenFutureCompletes(CasBlobDownloadEvent.sendEvent(buckEventBus, 1, digest.getSize()),
                GrpcRemoteExecutionClients.readByteStream(instanceName, digest, byteStreamStub,
                        data -> data.writeTo(outputStream)));
    }

    private <T> ListenableFuture<T> closeScopeWhenFutureCompletes(Scope scope, ListenableFuture<T> future) {
        future.addListener(() -> scope.close(), MoreExecutors.directExecutor());
        return future;
    }
}