public OMElement getCEPPublisher(OMElement request) throws XMLStreamException {
request.build();
request.detach();
OMElement tenantId =
request.getFirstChildWithName(
new QName(
ManagerServiceConstants.NAMESPACE, ManagerServiceConstants.ELEMENT_TENANT_ID));
OMElement executionPlan =
request.getFirstChildWithName(
new QName(
ManagerServiceConstants.NAMESPACE, ManagerServiceConstants.ELEMENT_EXEC_PLAN));
OMElement requesterIp =
request.getFirstChildWithName(
new QName(
ManagerServiceConstants.NAMESPACE, ManagerServiceConstants.ELEMENT_REQUESTER_IP));
String key = getKey(executionPlan.getText(), tenantId.getText());
log.info("CEP Publisher requested for " + key);
Set<Endpoint> endpointSet = cepPublishers.get(key);
Endpoint selectedEndpoint = selectEndpoint(endpointSet, requesterIp.getText());
OMElement response =
factory.createOMElement(
ManagerServiceConstants.ELEMENT_CEP_PUBLISHER_RESPONSE, OMNamespace);
if (selectedEndpoint != null) {
OMElement hostNameElement =
factory.createOMElement(ManagerServiceConstants.ELEMENT_HOST_NAME, OMNamespace);
OMElement portElement =
factory.createOMElement(ManagerServiceConstants.ELEMENT_PORT, OMNamespace);
OMText hostNameText = factory.createOMText(hostNameElement, selectedEndpoint.getHostName());
OMText portText =
factory.createOMText(portElement, Integer.toString(selectedEndpoint.getPort()));
hostNameElement.addChild(hostNameText);
portElement.addChild(portText);
response.addChild(hostNameElement);
response.addChild(portElement);
log.info(
"Returning CEP Publisher:"
+ selectedEndpoint.getHostName()
+ ":"
+ selectedEndpoint.getPort());
} else {
log.warn("No CEP publishers registered " + key);
}
return response;
}
private Endpoint selectEndpoint(Set<Endpoint> endpointSet, String requesterIp) {
Endpoint selectedEndpoint = null;
if (endpointSet != null && !endpointSet.isEmpty()) {
// If there's a storm receiver/cep publisher in the same host as requester IP select it
if ("".equals(requesterIp) == false) {
for (Endpoint endpoint : endpointSet) {
if (endpoint.getHostName().equals(requesterIp)) {
selectedEndpoint = endpoint;
if (log.isDebugEnabled()) {
log.debug(
"Selecting"
+ endpoint.toString()
+ " since it's in the same host as the requester");
}
break;
}
}
}
// If there are no endpoints in the same host. Select the endpoint with lease number of
// connections
if (selectedEndpoint == null) {
int minConnectionCount = Integer.MAX_VALUE;
for (Endpoint endpoint : endpointSet) {
if (log.isDebugEnabled()) {
log.debug(
"Endpoint "
+ endpoint.toString()
+ " has "
+ endpoint.getConnectionCount()
+ " connections.");
}
if (endpoint.getConnectionCount() < minConnectionCount) {
minConnectionCount = endpoint.getConnectionCount();
selectedEndpoint = endpoint;
}
}
}
selectedEndpoint.setConnectionCount(selectedEndpoint.getConnectionCount() + 1);
}
return selectedEndpoint;
}
