org.glowroot.agent.shaded.grpc.Contexts Maven / Gradle / Ivy
Show all versions of glowroot-agent-it-harness Show documentation
/*
* Copyright 2015, Google Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
*
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.glowroot.agent.shaded.grpc;
/**
* Utility methods for working with {@link Context}s in GRPC.
*/
public class Contexts {
/**
* Make the provided {@link Context} {@link Context#current()} for the creation of a listener
* to a received call and for all events received by that listener.
*
* This utility is expected to be used by {@link ServerInterceptor} implementations that need
* to augment the {@link Context} in which the application does work when receiving events from
* the client.
*
* @param context to make {@link Context#current()}.
* @param method being requested by the client.
* @param call used to send responses to client.
* @param headers received from client.
* @param next handler used to create the listener to be wrapped.
* @return listener that will receive events in the scope of the provided context.
*/
public static ServerCall.Listener interceptCall(
Context context,
MethodDescriptor method,
ServerCall call,
Metadata headers,
ServerCallHandler next) {
Context previous = context.attach();
try {
return new ContextualizedServerCallListener(
next.startCall(method, call, headers),
context);
} finally {
context.detach(previous);
}
}
/**
* Implementation of {@link org.glowroot.agent.shaded.grpc.ForwardingServerCallListener} that attaches a context before
* dispatching calls to the delegate and detaches them after the call completes.
*/
private static class ContextualizedServerCallListener extends
ForwardingServerCallListener.SimpleForwardingServerCallListener {
private final Context context;
public ContextualizedServerCallListener(ServerCall.Listener delegate, Context context) {
super(delegate);
this.context = context;
}
@Override
public void onMessage(ReqT message) {
Context previous = context.attach();
try {
super.onMessage(message);
} finally {
context.detach(previous);
}
}
@Override
public void onHalfClose() {
Context previous = context.attach();
try {
super.onHalfClose();
} finally {
context.detach(previous);
}
}
@Override
public void onCancel() {
Context previous = context.attach();
try {
super.onCancel();
} finally {
context.detach(previous);
}
}
@Override
public void onComplete() {
Context previous = context.attach();
try {
super.onComplete();
} finally {
context.detach(previous);
}
}
@Override
public void onReady() {
Context previous = context.attach();
try {
super.onReady();
} finally {
context.detach(previous);
}
}
}
}