/**
* Change topology.
*
* @param parent Grid to execute tasks on.
* @param add New nodes count.
* @param rmv Remove nodes count.
* @param type Type of nodes to manipulate.
*/
private static void changeTopology(Ignite parent, int add, int rmv, String type) {
Collection<ComputeTaskFuture<?>> tasks = new ArrayList<>();
IgniteCompute comp = parent.compute().withAsync();
// Start nodes in parallel.
while (add-- > 0) {
comp.execute(ClientStartNodeTask.class, type);
tasks.add(comp.future());
}
for (ComputeTaskFuture<?> task : tasks) task.get();
// Stop nodes in sequence.
while (rmv-- > 0) parent.compute().execute(ClientStopNodeTask.class, type);
// Wait for node stops.
// U.sleep(1000);
Collection<String> gridNames = new ArrayList<>();
for (Ignite g : G.allGrids()) gridNames.add(g.name());
parent.log().info(">>> Available grids: " + gridNames);
}
/**
* Listen to events that happen only on local node.
*
* @throws IgniteException If failed.
*/
private static void localListen() throws IgniteException {
System.out.println();
System.out.println(">>> Local event listener example.");
Ignite ignite = Ignition.ignite();
IgnitePredicate<TaskEvent> lsnr =
evt -> {
System.out.println(
"Received task event [evt=" + evt.name() + ", taskName=" + evt.taskName() + ']');
return true; // Return true to continue listening.
};
// Register event listener for all local task execution events.
ignite.events().localListen(lsnr, EVTS_TASK_EXECUTION);
// Generate task events.
ignite
.compute()
.withName("example-event-task")
.run(() -> System.out.println("Executing sample job."));
// Unsubscribe local task event listener.
ignite.events().stopLocalListen(lsnr);
}
/** @throws Exception If failed. */
@SuppressWarnings({"AssignmentToCatchBlockParameter"})
public void testCancel() throws Exception {
Ignite ignite = G.ignite(getTestGridName());
ignite
.compute()
.localDeployTask(GridCancelTestTask.class, GridCancelTestTask.class.getClassLoader());
ComputeTaskFuture<?> res0 =
executeAsync(
ignite.compute().withTimeout(maxJobExecTime * 2),
GridCancelTestTask.class.getName(),
null);
try {
Object res = res0.get();
info("Cancel test result: " + res);
synchronized (mux) {
// Every execute must be called.
assert execCnt <= SPLIT_COUNT : "Invalid execute count: " + execCnt;
// Job returns 1 if was cancelled.
assert (Integer) res <= SPLIT_COUNT : "Invalid task result: " + res;
// Should be exactly the same as Jobs number.
assert cancelCnt <= SPLIT_COUNT : "Invalid cancel count: " + cancelCnt;
// One per start and one per stop and some that come with heartbeats.
assert colResolutionCnt > SPLIT_COUNT + 1
: "Invalid collision resolution count: " + colResolutionCnt;
}
} catch (ComputeTaskTimeoutException e) {
error("Task execution got timed out.", e);
} catch (Exception e) {
assert e.getCause() != null;
if (e.getCause() instanceof IgniteCheckedException) e = (Exception) e.getCause();
if (e.getCause() instanceof IOException) e = (Exception) e.getCause();
assert e.getCause() instanceof InterruptedException
: "Invalid exception cause: " + e.getCause();
}
}
/**
* Listen to events coming from all cluster nodes.
*
* @throws IgniteException If failed.
*/
private static void remoteListen() throws IgniteException {
System.out.println();
System.out.println(">>> Remote event listener example.");
// This optional local callback is called for each event notification
// that passed remote predicate listener.
IgniteBiPredicate<UUID, TaskEvent> locLsnr =
(nodeId, evt) -> {
// Remote filter only accepts tasks whose name being with "good-task" prefix.
assert evt.taskName().startsWith("good-task");
System.out.println(
"Received task event [evt=" + evt.name() + ", taskName=" + evt.taskName());
return true; // Return true to continue listening.
};
// Remote filter which only accepts tasks whose name begins with "good-task" prefix.
IgnitePredicate<TaskEvent> rmtLsnr = evt -> evt.taskName().startsWith("good-task");
Ignite ignite = Ignition.ignite();
// Register event listeners on all nodes to listen for task events.
ignite.events().remoteListen(locLsnr, rmtLsnr, EVTS_TASK_EXECUTION);
// Generate task events.
for (int i = 0; i < 10; i++) {
ignite
.compute()
.withName(i < 5 ? "good-task-" + i : "bad-task-" + i)
.run(
new IgniteRunnable() {
// Auto-inject task session.
@TaskSessionResource private ComputeTaskSession ses;
@Override
public void run() {
System.out.println("Executing sample job for task: " + ses.getTaskName());
}
});
}
}
/**
* Example for start/stop node tasks.
*
* @param args Not used.
*/
public static void main(String[] args) {
String nodeType = "tcp+ssl";
// Start initial node = 1
try (Ignite g = G.start(NODE_CFG.get(nodeType))) {
// Change topology.
changeTopology(g, 4, 1, nodeType);
changeTopology(g, 1, 4, nodeType);
// Stop node by id = 0
g.compute().execute(ClientStopNodeTask.class, g.cluster().localNode().id().toString());
// Wait for node stops.
// U.sleep(1000);
assert G.allGrids().isEmpty();
} catch (Exception e) {
System.err.println("Uncaught exception: " + e.getMessage());
e.printStackTrace(System.err);
}
}