/*
* Copyright (c) 2014 Spotify AB.
*
* 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 com.spotify.helios.agent;
import com.spotify.docker.client.DefaultDockerClient;
import com.spotify.docker.client.DockerCertificates;
import com.spotify.docker.client.DockerClient;
import com.spotify.docker.client.DockerException;
import com.spotify.docker.client.messages.ContainerExit;
import com.spotify.docker.client.messages.ContainerInfo;
import java.net.URI;
/**
* A {@link DockerClient} that overrides {@link #waitContainer} to poll instead of block
* indefinitely. See the source code for details as to why this needs to exist.
*/
public class PollingDockerClient extends DefaultDockerClient {
private static final long WAIT_INSPECT_INTERVAL_MILLIS =
Long.getLong("HELIOS_WAIT_INSPECT_INTERVAL_MILLIS", 5000);
public PollingDockerClient(final String uri) {
super(uri);
}
public PollingDockerClient(final URI uri) {
super(uri);
}
public PollingDockerClient(final URI uri, DockerCertificates dockerCertificates) {
super(uri, dockerCertificates);
}
@Override
public ContainerExit waitContainer(final String containerId)
throws DockerException, InterruptedException {
// XXX (dano): We're doing this poll loop instead of docker.waitContainer() because we saw the
// agent hang forever on waitContainer after the socket got into a weird half-open
// state where the kernel (netstat/lsof) would only show one end of the connection
// and restarting docker would not close the socket. ¯\_(ツ)_/¯
while (true) {
final ContainerInfo info = inspectContainer(containerId);
if (!info.state().running()) {
return new ContainerExit(info.state().exitCode());
}
Thread.sleep(WAIT_INSPECT_INTERVAL_MILLIS);
}
}
}