initial notification in ngsiv2 is procesed as Bad HTTP notification

[AlvaroVega]

When CB is notifying in ngsiv2 several entities in the same fiware-servicepath (like /)

i.e.:

time=2021-05-20T13:37:25.092Z | lvl=INFO | corr=83099026-b970-11eb-a32f-0242ac110011 | trans=d66f89f2-81b3-450b-8353-f6cc68bafbc5 | srv=smartcity | subsrv=/ | comp=cygnus-ngsi | op=getEvents | msg=com.telefonica.iot.cygnus.handlers.NGSIRestHandler[324] : [NGSIRestHandler] Received data ({"subscriptionId":"60a661256bbc23164e62d6fb","data":[{"id":"estacion1","type":"WeatherObserved","dateObserved":{"type":"DateTime","value":"2021-02-18T06:00:45.145Z","metadata":{}},"illuminance":{"type":"Number","value":3,"metadata":{}},"solarRadiation":{"type":"Number","value":2,"metadata":{}}},{"id":"WeatherObserved:disp1234bc","type":"WeatherObserved","TimeInstant":{"type":"DateTime","value":"2021-05-20T13:33:07.068Z","metadata":{}},"dateObserved":{"type":"DateTime","value":"2021-05-20T13:32:43.772Z","metadata":{}}}]})
time=2021-05-20T13:37:25.094Z | lvl=WARN | corr=83099026-b970-11eb-a32f-0242ac110011 | trans=d66f89f2-81b3-450b-8353-f6cc68bafbc5 | srv=smartcity | subsrv=/ | comp=cygnus-ngsi | op=getEvents | msg=com.telefonica.iot.cygnus.handlers.NGSIRestHandler[363] : [NGSIRestHandler] Bad HTTP notification ('fiware-servicepath' header value does not match the number of notified context responses
time=2021-05-20T13:37:25.102Z | lvl=WARN | corr=83099026-b970-11eb-a32f-0242ac110011 | trans=d66f89f2-81b3-450b-8353-f6cc68bafbc5 | srv=smartcity | subsrv=/ | comp=cygnus-ngsi | op=doPost | msg=org.apache.flume.source.http.HTTPSource$FlumeHTTPServlet[237] : Received bad request from client.
org.apache.flume.source.http.HTTPBadRequestException: 'fiware-servicepath' header value does not match the number of notified context responses
at com.telefonica.iot.cygnus.handlers.NGSIRestHandler.getEvents(NGSIRestHandler.java:366)
at org.apache.flume.source.http.HTTPSource$FlumeHTTPServlet.doPost(HTTPSource.java:235)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:841)
at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:535)
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143)
at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:548)
at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132)
at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:190)
at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1595)
at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:188)
at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1253)
at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:168)
at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:473)
at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1564)
at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:166)
at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1155)
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132)
at org.eclipse.jetty.server.Server.handle(Server.java:564)
at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:317)
at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:251)
at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:279)
at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:110)
at org.eclipse.jetty.io.ChannelEndPoint$2.run(ChannelEndPoint.java:124)
at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:673)
at org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:591)
at java.lang.Thread.run(Thread.java:748)

done in

fiware-cygnus/cygnus-ngsi/src/main/java/com/telefonica/iot/cygnus/handlers/NGSIRestHandler.java

Lines 361 to 369 in 3b93df3

	if (servicePaths.length != ncr.getContextResponses().size()) {
	serviceMetrics.add(service, servicePath, 1, request.getContentLength(), 0, 1, 0, 0, 0, 0, 0);
	LOGGER.warn("[NGSIRestHandler] Bad HTTP notification ('"
	+ CommonConstants.HEADER_FIWARE_SERVICE_PATH
	+ "' header value does not match the number of notified context responses");
	throw new HTTPBadRequestException(
	"'" + CommonConstants.HEADER_FIWARE_SERVICE_PATH
	+ "' header value does not match the number of notified context responses");
	} // if

According with NGSv2 spec:
https://fiware-orion.readthedocs.io/en/master/user/initial_notification/index.html

As happens with non-initial notification, the Fiware-ServicePath header is included in initial notification. However, note that an initial notification potentially includes several (more than one) entities, which may belong to different service paths. Thus, a list of comma separated values is used (the first element in the Fiware-ServicePath list corresponding to the first entity, etc.). 

IMHO which may belong to different service paths or the same service path

[AlvaroVega]

related
telefonicaid/fiware-orion#3857

[fgalan]

Fixed by PR #2043

This issue has a continuation in #2044