forcePing = false;
}
/** Issue a cluster local heartbeat (into the repository) **/
private void issueClusterLocalHeartbeat() {
ResourceResolver resourceResolver = null;
final String myClusterNodePath = getLocalClusterNodePath();
final Calendar currentTime = Calendar.getInstance();
try {
resourceResolver = getResourceResolver();
if (resourceResolver == null) {
logger.error("issueClusterLocalHeartbeat: no resourceresolver available!");
return;
}
final Resource resource = ResourceHelper.getOrCreateResource(
resourceResolver, myClusterNodePath);
final ModifiableValueMap resourceMap = resource.adaptTo(ModifiableValueMap.class);
if (firstHeartbeatWritten!=-1 && lastHeartbeatWritten!=null) {
// SLING-2892: additional paranoia check
// after the first heartbeat, check if there's someone else using
// the same sling.id in this cluster
final long timeSinceFirstHeartbeat =
System.currentTimeMillis() - firstHeartbeatWritten;
if (timeSinceFirstHeartbeat > 2*config.getHeartbeatInterval()) {
// but wait at least 2 heartbeat intervals to handle the situation
// where a bundle is refreshed, and startup cases.
final Calendar lastHeartbeat = resourceMap.get("lastHeartbeat", Calendar.class);
if (lastHeartbeat!=null) {
// if there is a heartbeat value, check if it is what I've written
// the last time
if (!lastHeartbeatWritten.getTime().equals(lastHeartbeat.getTime())) {
// then we've likely hit the situation where there is another
// sling instance accessing the same repository (ie in the same cluster)
// using the same sling.id - hence writing to the same
// resource
logger.error("issueClusterLocalHeartbeat: SLING-2892: Detected unexpected, concurrent update of: "+
myClusterNodePath+" 'lastHeartbeat'. If not done manually, " +
"this likely indicates that there is more than 1 instance running in this cluster" +
" with the same sling.id. My sling.id is "+slingId+"." +
" Check for sling.id.file in your installation of all instances in this cluster " +
"to verify this! Duplicate sling.ids are not allowed within a cluster!");
}
}
}
// SLING-2901 : robust paranoia check: on first heartbeat write, the
// 'runtimeId' is set as a property (ignoring any former value).
// If in subsequent calls the value of 'runtimeId' changes, then
// there is someone else around with the same slingId.
final String readRuntimeId = resourceMap.get("runtimeId", String.class);
if ( readRuntimeId == null ) { // SLING-3977
// someone deleted the resource property
firstHeartbeatWritten = -1;
} else if (!runtimeId.equals(readRuntimeId)) {
logger.error("issueClusterLocalHeartbeat: SLING-2091: Detected more than 1 instance running in this cluster " +
" with the same sling.id. My sling.id is "+slingId+", " +
" Check for sling.id.file in your installation of all instances in this cluster " +
"to verify this! Duplicate sling.ids are not allowed within a cluster!");
logger.error("issueClusterLocalHeartbeat: sending TOPOLOGY_CHANGING before self-disabling.");
discoveryService.forcedShutdown();
logger.error("issueClusterLocalHeartbeat: disabling discovery.impl");
activated = false;
if (context!=null) {
// disable all components
try {
context.getBundleContext().getBundle().stop();
} catch (BundleException e) {
logger.warn("issueClusterLocalHeartbeat: could not stop bundle: "+e, e);
// then disable all compnoents instead
context.disableComponent(null);
}
}
return;
}
}
resourceMap.put("lastHeartbeat", currentTime);
if (firstHeartbeatWritten==-1) {
resourceMap.put("runtimeId", runtimeId);
}
if (resetLeaderElectionId || !resourceMap.containsKey("leaderElectionId")) {
int maxLongLength = String.valueOf(Long.MAX_VALUE).length();
String currentTimeMillisStr = String.format("%0"
+ maxLongLength + "d", System.currentTimeMillis());
String prefix = "0";
String leaderElectionRepositoryDescriptor = config.getLeaderElectionRepositoryDescriptor();
if (leaderElectionRepositoryDescriptor!=null && leaderElectionRepositoryDescriptor.length()!=0) {
// when this property is configured, check the value of the repository descriptor
// and if that value is set, include it in the leader election id
final Session session = resourceResolver.adaptTo(Session.class);
if ( session != null ) {
String value = session.getRepository()
.getDescriptor(leaderElectionRepositoryDescriptor);
if (value != null && value.equalsIgnoreCase("true")) {
prefix = "1";
}
}
}
resourceMap.put("leaderElectionId", prefix + "_"
+ currentTimeMillisStr + "_" + slingId);
resetLeaderElectionId = false;
}
resourceResolver.commit();
// SLING-2892: only in success case: remember the last heartbeat value written
lastHeartbeatWritten = currentTime;
// and set the first heartbeat written value - if it is not already set
if (firstHeartbeatWritten==-1) {
firstHeartbeatWritten = System.currentTimeMillis();
}
} catch (LoginException e) {
logger.error("issueHeartbeat: could not log in administratively: "
+ e, e);
} catch (PersistenceException e) {
logger.error("issueHeartbeat: Got a PersistenceException: "
+ myClusterNodePath + " " + e, e);
} finally {
if (resourceResolver != null) {
resourceResolver.close();
}
}
}