/**
* Recover an already existing container. This is a blocking call and returns only when the
* container exits. Note that the container must have been activated prior to this call.
*
* @param ctx encapsulates information necessary to reacquire container
* @return The exit code of the pre-existing container
* @throws IOException
* @throws InterruptedException
*/
public int reacquireContainer(ContainerReacquisitionContext ctx)
throws IOException, InterruptedException {
Container container = ctx.getContainer();
String user = ctx.getUser();
ContainerId containerId = ctx.getContainerId();
Path pidPath = getPidFilePath(containerId);
if (pidPath == null) {
LOG.warn(containerId + " is not active, returning terminated error");
return ExitCode.TERMINATED.getExitCode();
}
String pid = null;
pid = ProcessIdFileReader.getProcessId(pidPath);
if (pid == null) {
throw new IOException("Unable to determine pid for " + containerId);
}
LOG.info("Reacquiring " + containerId + " with pid " + pid);
ContainerLivenessContext livenessContext =
new ContainerLivenessContext.Builder()
.setContainer(container)
.setUser(user)
.setPid(pid)
.build();
while (isContainerAlive(livenessContext)) {
Thread.sleep(1000);
}
// wait for exit code file to appear
String exitCodeFile = ContainerLaunch.getExitCodeFile(pidPath.toString());
File file = new File(exitCodeFile);
final int sleepMsec = 100;
int msecLeft = 2000;
while (!file.exists() && msecLeft >= 0) {
if (!isContainerActive(containerId)) {
LOG.info(containerId + " was deactivated");
return ExitCode.TERMINATED.getExitCode();
}
Thread.sleep(sleepMsec);
msecLeft -= sleepMsec;
}
if (msecLeft < 0) {
throw new IOException("Timeout while waiting for exit code from " + containerId);
}
try {
return Integer.parseInt(FileUtils.readFileToString(file).trim());
} catch (NumberFormatException e) {
throw new IOException("Error parsing exit code from pid " + pid, e);
}
}
/**
* Get the process-identifier for the container
*
* @param containerID
* @return the processid of the container if it has already launched, otherwise return null
*/
public String getProcessId(ContainerId containerID) {
String pid = null;
Path pidFile = pidFiles.get(containerID);
if (pidFile == null) {
// This container isn't even launched yet.
return pid;
}
try {
pid = ProcessIdFileReader.getProcessId(pidFile);
} catch (IOException e) {
LOG.error("Got exception reading pid from pid-file " + pidFile, e);
}
return pid;
}