io.grpc.internal.AbstractClientStream Maven / Gradle / Ivy
/*
* Copyright 2014 The gRPC Authors
*
* 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 io.grpc.internal;
import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.base.Preconditions.checkState;
import static io.grpc.internal.GrpcUtil.CONTENT_ENCODING_KEY;
import static io.grpc.internal.GrpcUtil.MESSAGE_ENCODING_KEY;
import static io.grpc.internal.GrpcUtil.TIMEOUT_KEY;
import static java.lang.Math.max;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.base.Preconditions;
import io.grpc.CallOptions;
import io.grpc.Codec;
import io.grpc.Compressor;
import io.grpc.Deadline;
import io.grpc.Decompressor;
import io.grpc.DecompressorRegistry;
import io.grpc.Metadata;
import io.grpc.Status;
import io.grpc.internal.ClientStreamListener.RpcProgress;
import java.io.InputStream;
import java.util.concurrent.TimeUnit;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.annotation.Nullable;
/**
* The abstract base class for {@link ClientStream} implementations. Extending classes only need to
* implement {@link #transportState()} and {@link #abstractClientStreamSink()}. Must only be called
* from the sending application thread.
*/
public abstract class AbstractClientStream extends AbstractStream
implements ClientStream, MessageFramer.Sink {
private static final Logger log = Logger.getLogger(AbstractClientStream.class.getName());
/**
* A sink for outbound operations, separated from the stream simply to avoid name
* collisions/confusion. Only called from application thread.
*/
protected interface Sink {
/**
* Sends the request headers to the remote end point.
*
* @param metadata the metadata to be sent
* @param payload the payload needs to be sent in the headers if not null. Should only be used
* when sending an unary GET request
*/
void writeHeaders(Metadata metadata, @Nullable byte[] payload);
/**
* Sends an outbound frame to the remote end point.
*
* @param frame a buffer containing the chunk of data to be sent, or {@code null} if {@code
* endOfStream} with no data to send
* @param endOfStream {@code true} if this is the last frame; {@code flush} is guaranteed to be
* {@code true} if this is {@code true}
* @param flush {@code true} if more data may not be arriving soon
* @Param numMessages the number of messages this series of frames represents, must be >= 0.
*/
void writeFrame(
@Nullable WritableBuffer frame, boolean endOfStream, boolean flush, int numMessages);
/**
* Requests up to the given number of messages from the call to be delivered to the client. This
* should end up triggering {@link TransportState#requestMessagesFromDeframer(int)} on the
* transport thread.
*/
void request(int numMessages);
/**
* Tears down the stream, typically in the event of a timeout. This method may be called
* multiple times and from any thread.
*
* This is a clone of {@link ClientStream#cancel(Status)};
* {@link AbstractClientStream#cancel} delegates to this method.
*/
void cancel(Status status);
}
private final TransportTracer transportTracer;
private final Framer framer;
private boolean shouldBeCountedForInUse;
private boolean useGet;
private Metadata headers;
/**
* Whether cancel() has been called. This is not strictly necessary, but removes the delay between
* cancel() being called and isReady() beginning to return false, since cancel is commonly
* processed asynchronously.
*/
private volatile boolean cancelled;
protected AbstractClientStream(
WritableBufferAllocator bufferAllocator,
StatsTraceContext statsTraceCtx,
TransportTracer transportTracer,
Metadata headers,
CallOptions callOptions,
boolean useGet) {
checkNotNull(headers, "headers");
this.transportTracer = checkNotNull(transportTracer, "transportTracer");
this.shouldBeCountedForInUse = GrpcUtil.shouldBeCountedForInUse(callOptions);
this.useGet = useGet;
if (!useGet) {
framer = new MessageFramer(this, bufferAllocator, statsTraceCtx);
this.headers = headers;
} else {
framer = new GetFramer(headers, statsTraceCtx);
}
}
@Override
public void setDeadline(Deadline deadline) {
headers.discardAll(TIMEOUT_KEY);
long effectiveTimeout = max(0, deadline.timeRemaining(TimeUnit.NANOSECONDS));
headers.put(TIMEOUT_KEY, effectiveTimeout);
}
@Override
public void setMaxOutboundMessageSize(int maxSize) {
framer.setMaxOutboundMessageSize(maxSize);
}
@Override
public void setMaxInboundMessageSize(int maxSize) {
transportState().setMaxInboundMessageSize(maxSize);
}
@Override
public final void setFullStreamDecompression(boolean fullStreamDecompression) {
transportState().setFullStreamDecompression(fullStreamDecompression);
}
@Override
public final void setDecompressorRegistry(DecompressorRegistry decompressorRegistry) {
transportState().setDecompressorRegistry(decompressorRegistry);
}
/** {@inheritDoc} */
@Override
protected abstract TransportState transportState();
@Override
public final void start(ClientStreamListener listener) {
transportState().setListener(listener);
if (!useGet) {
abstractClientStreamSink().writeHeaders(headers, null);
headers = null;
}
}
/**
* Sink for transport to be called to perform outbound operations. Each stream must have its own
* unique sink.
*/
protected abstract Sink abstractClientStreamSink();
@Override
protected final Framer framer() {
return framer;
}
/**
* Returns true if this stream should be counted when determining the in-use state of the
* transport.
*/
public final boolean shouldBeCountedForInUse() {
return shouldBeCountedForInUse;
}
@Override
public final void request(int numMessages) {
abstractClientStreamSink().request(numMessages);
}
@Override
public final void deliverFrame(
WritableBuffer frame, boolean endOfStream, boolean flush, int numMessages) {
Preconditions.checkArgument(frame != null || endOfStream, "null frame before EOS");
abstractClientStreamSink().writeFrame(frame, endOfStream, flush, numMessages);
}
@Override
public final void halfClose() {
if (!transportState().isOutboundClosed()) {
transportState().setOutboundClosed();
endOfMessages();
}
}
@Override
public final void cancel(Status reason) {
Preconditions.checkArgument(!reason.isOk(), "Should not cancel with OK status");
cancelled = true;
abstractClientStreamSink().cancel(reason);
}
@Override
public final boolean isReady() {
return super.isReady() && !cancelled;
}
protected TransportTracer getTransportTracer() {
return transportTracer;
}
/** This should only called from the transport thread. */
protected abstract static class TransportState extends AbstractStream.TransportState {
/** Whether listener.closed() has been called. */
private final StatsTraceContext statsTraceCtx;
private boolean listenerClosed;
private ClientStreamListener listener;
private boolean fullStreamDecompression;
private DecompressorRegistry decompressorRegistry = DecompressorRegistry.getDefaultInstance();
private boolean deframerClosed = false;
private Runnable deframerClosedTask;
/** Whether the client has half-closed the stream. */
private volatile boolean outboundClosed;
/**
* Whether the stream is closed from the transport's perspective. This can differ from {@link
* #listenerClosed} because there may still be messages buffered to deliver to the application.
*/
private boolean statusReported;
/** True if the status reported (set via {@link #transportReportStatus}) is OK. */
private boolean statusReportedIsOk;
protected TransportState(
int maxMessageSize,
StatsTraceContext statsTraceCtx,
TransportTracer transportTracer) {
super(maxMessageSize, statsTraceCtx, transportTracer);
this.statsTraceCtx = checkNotNull(statsTraceCtx, "statsTraceCtx");
}
private void setFullStreamDecompression(boolean fullStreamDecompression) {
this.fullStreamDecompression = fullStreamDecompression;
}
private void setDecompressorRegistry(DecompressorRegistry decompressorRegistry) {
checkState(this.listener == null, "Already called start");
this.decompressorRegistry =
checkNotNull(decompressorRegistry, "decompressorRegistry");
}
@VisibleForTesting
public final void setListener(ClientStreamListener listener) {
checkState(this.listener == null, "Already called setListener");
this.listener = checkNotNull(listener, "listener");
}
@Override
public void deframerClosed(boolean hasPartialMessage) {
checkState(statusReported, "status should have been reported on deframer closed");
deframerClosed = true;
if (statusReportedIsOk && hasPartialMessage) {
transportReportStatus(
Status.INTERNAL.withDescription("Encountered end-of-stream mid-frame"),
true,
new Metadata());
}
if (deframerClosedTask != null) {
deframerClosedTask.run();
deframerClosedTask = null;
}
}
@Override
protected final ClientStreamListener listener() {
return listener;
}
private final void setOutboundClosed() {
outboundClosed = true;
}
protected final boolean isOutboundClosed() {
return outboundClosed;
}
/**
* Called by transport implementations when they receive headers.
*
* @param headers the parsed headers
*/
protected void inboundHeadersReceived(Metadata headers) {
checkState(!statusReported, "Received headers on closed stream");
statsTraceCtx.clientInboundHeaders();
boolean compressedStream = false;
String streamEncoding = headers.get(CONTENT_ENCODING_KEY);
if (fullStreamDecompression && streamEncoding != null) {
if (streamEncoding.equalsIgnoreCase("gzip")) {
setFullStreamDecompressor(new GzipInflatingBuffer());
compressedStream = true;
} else if (!streamEncoding.equalsIgnoreCase("identity")) {
deframeFailed(
Status.INTERNAL
.withDescription(
String.format("Can't find full stream decompressor for %s", streamEncoding))
.asRuntimeException());
return;
}
}
String messageEncoding = headers.get(MESSAGE_ENCODING_KEY);
if (messageEncoding != null) {
Decompressor decompressor = decompressorRegistry.lookupDecompressor(messageEncoding);
if (decompressor == null) {
deframeFailed(
Status.INTERNAL
.withDescription(String.format("Can't find decompressor for %s", messageEncoding))
.asRuntimeException());
return;
} else if (decompressor != Codec.Identity.NONE) {
if (compressedStream) {
deframeFailed(
Status.INTERNAL
.withDescription(
String.format("Full stream and gRPC message encoding cannot both be set"))
.asRuntimeException());
return;
}
setDecompressor(decompressor);
}
}
listener().headersRead(headers);
}
/**
* Processes the contents of a received data frame from the server.
*
* @param frame the received data frame. Its ownership is transferred to this method.
*/
protected void inboundDataReceived(ReadableBuffer frame) {
checkNotNull(frame, "frame");
boolean needToCloseFrame = true;
try {
if (statusReported) {
log.log(Level.INFO, "Received data on closed stream");
return;
}
needToCloseFrame = false;
deframe(frame);
} finally {
if (needToCloseFrame) {
frame.close();
}
}
}
/**
* Processes the trailers and status from the server.
*
* @param trailers the received trailers
* @param status the status extracted from the trailers
*/
protected void inboundTrailersReceived(Metadata trailers, Status status) {
checkNotNull(status, "status");
checkNotNull(trailers, "trailers");
if (statusReported) {
log.log(Level.INFO, "Received trailers on closed stream:\n {1}\n {2}",
new Object[]{status, trailers});
return;
}
statsTraceCtx.clientInboundTrailers(trailers);
transportReportStatus(status, false, trailers);
}
/**
* Report stream closure with status to the application layer if not already reported. This
* method must be called from the transport thread.
*
* @param status the new status to set
* @param stopDelivery if {@code true}, interrupts any further delivery of inbound messages that
* may already be queued up in the deframer. If {@code false}, the listener will be
* notified immediately after all currently completed messages in the deframer have been
* delivered to the application.
* @param trailers new instance of {@code Trailers}, either empty or those returned by the
* server
*/
public final void transportReportStatus(final Status status, boolean stopDelivery,
final Metadata trailers) {
transportReportStatus(status, RpcProgress.PROCESSED, stopDelivery, trailers);
}
/**
* Report stream closure with status to the application layer if not already reported. This
* method must be called from the transport thread.
*
* @param status the new status to set
* @param rpcProgress RPC progress that the
* {@link ClientStreamListener#closed(Status, RpcProgress, Metadata)}
* will receive
* @param stopDelivery if {@code true}, interrupts any further delivery of inbound messages that
* may already be queued up in the deframer and overrides any previously queued status.
* If {@code false}, the listener will be notified immediately after all currently
* completed messages in the deframer have been delivered to the application.
* @param trailers new instance of {@code Trailers}, either empty or those returned by the
* server
*/
public final void transportReportStatus(
final Status status,
final RpcProgress rpcProgress,
boolean stopDelivery,
final Metadata trailers) {
checkNotNull(status, "status");
checkNotNull(trailers, "trailers");
// If stopDelivery, we continue in case previous invocation is waiting for stall
if (statusReported && !stopDelivery) {
return;
}
statusReported = true;
statusReportedIsOk = status.isOk();
onStreamDeallocated();
if (deframerClosed) {
deframerClosedTask = null;
closeListener(status, rpcProgress, trailers);
} else {
deframerClosedTask =
new Runnable() {
@Override
public void run() {
closeListener(status, rpcProgress, trailers);
}
};
closeDeframer(stopDelivery);
}
}
/**
* Closes the listener if not previously closed.
*
* @throws IllegalStateException if the call has not yet been started.
*/
private void closeListener(
Status status, RpcProgress rpcProgress, Metadata trailers) {
if (!listenerClosed) {
listenerClosed = true;
statsTraceCtx.streamClosed(status);
listener().closed(status, rpcProgress, trailers);
if (getTransportTracer() != null) {
getTransportTracer().reportStreamClosed(status.isOk());
}
}
}
}
private class GetFramer implements Framer {
private Metadata headers;
private boolean closed;
private final StatsTraceContext statsTraceCtx;
private byte[] payload;
public GetFramer(Metadata headers, StatsTraceContext statsTraceCtx) {
this.headers = checkNotNull(headers, "headers");
this.statsTraceCtx = checkNotNull(statsTraceCtx, "statsTraceCtx");
}
@Override
public void writePayload(InputStream message) {
checkState(payload == null, "writePayload should not be called multiple times");
try {
payload = IoUtils.toByteArray(message);
} catch (java.io.IOException ex) {
throw new RuntimeException(ex);
}
statsTraceCtx.outboundMessage(0);
statsTraceCtx.outboundMessageSent(0, payload.length, payload.length);
statsTraceCtx.outboundUncompressedSize(payload.length);
// NB(zhangkun83): this is not accurate, because the underlying transport will probably encode
// it using e.g., base64. However, we are not supposed to know such detail here.
//
// We don't want to move this line to where the encoding happens either, because we'd better
// contain the message stats reporting in Framer as suggested in StatsTraceContext.
// Scattering the reporting sites increases the risk of mis-counting or double-counting.
//
// Because the payload is usually very small, people shouldn't care about the size difference
// caused by encoding.
statsTraceCtx.outboundWireSize(payload.length);
}
@Override
public void flush() {}
@Override
public boolean isClosed() {
return closed;
}
/** Closes, with flush. */
@Override
public void close() {
closed = true;
checkState(payload != null,
"Lack of request message. GET request is only supported for unary requests");
abstractClientStreamSink().writeHeaders(headers, payload);
payload = null;
headers = null;
}
/** Closes, without flush. */
@Override
public void dispose() {
closed = true;
payload = null;
headers = null;
}
// Compression is not supported for GET encoding.
@Override
public Framer setMessageCompression(boolean enable) {
return this;
}
@Override
public Framer setCompressor(Compressor compressor) {
return this;
}
// TODO(zsurocking): support this
@Override
public void setMaxOutboundMessageSize(int maxSize) {}
}
}