[HTTPTrigger] Send 503 instead of 500 on processing rejected

[csc-gip]

xyna-factory/server/src/com/gip/xyna/xdev/xfractmod/xmdm/EventListener.java

Lines 125 to 128 in 7565a09

	/**
	* called if no thread could be started to process filters.
	*/
	protected abstract void onProcessingRejected(String cause, I con);

xyna-factory/server/src/com/gip/xyna/xdev/xfractmod/xmdm/EventListener.java

Lines 677 to 680 in 7565a09

	String rejection = receiveControlAlgorithm.notifyReceive();
	if( rejection != null ) {
	onProcessingRejectedProxy(rejection, tc);
	return null;

xyna-factory/server/src/com/gip/xyna/xact/trigger/ReceiveControlAlgorithm.java

Lines 66 to 75 in 7565a09

	public String notifyReceive() {
	long cnt = currentActiveEvents.incrementAndGet();
	if ( maxReceives <= -1) {
	return null; //unbegrenzte Receives
	}
	if( cnt > maxReceives ) {
	return SERVER_LOAD_TOO_HIGH_MESSAGE;
	}
	return null;
	}

xyna-factory/modules/xact/http/triggerimpl/HTTPTrigger/src/com/gip/xyna/xact/trigger/HTTPTrigger.java

Lines 414 to 417 in 7565a09

	public void onProcessingRejected(String s, HTTPTriggerConnection con) {
	try {
	rejectCounter.incrementAndGet();
	con.sendError(s);

We should send the retryable error code 503 or 429 in case the max trigger events are reached instead of a non retryable 500
https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/503
https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/500
https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/429