Created question in FIWARE Q/A platform on 09-09-2019 at 23:09
Please, ANSWER this question AT https://stackoverflow.com/questions/57861531/cygnus-doesnt-persist-data-because-namespace-name-generated-is-too-long-127

Question:
Cygnus doesn't persist data because: "namespace name generated is too long >127"

Description:
After some days breaking my head because cygnus persist randomly the updates, I have found in the logs that the size of a generated name space is too long.

I'm working on Centos 7
my entities use the standard type: BikeHireDockingStation
The error says that the namespace generate is too long (127 caracteres). It generates 167:

sth_malaga.sth_/urn:ngsi-ld:BikeHireDockingStation:10_BikeHireDockingStation.aggr.$_id.entityId_1id.entityType_1id.attrName_1id.resolution_1_id.origin_1

but even if I change the type to bike, the size is 124.

here you can see the part of the log error that I obtain when I call:
$ docker container logs fiware-cygnus

time=2019-09-09T21:14:14.176Z | lvl=ERROR | corr=N/A | trans=N/A | srv=N/A |
subsrv=N/A | comp=cygnus-ngsi | op=processRollbackedBatches |
msg=com.telefonica.iot.cygnus.sinks.NGSISink[399] : CygnusPersistenceError. -,
Command failed with error 67: 'namespace name generated from index name
"sth_malaga.sth_/urn:ngsi-ld:BikeHireDockingStation:10_BikeHireDockingStation.aggr.$_id.entityId_1id.entityType_1id.attrName_1id.resolution_1_id.origin_1"
is too long (127 byte max)' on server mongo-db:27017.
The full response is

.
Stack trace:
[com.telefonica.iot.cygnus.sinks.NGSISTHSink$STHAggregator.persist(NGSISTHSink.java:374),
com.telefonica.iot.cygnus.sinks.NGSISTHSink.persistBatch(NGSISTHSink.java:108),
com.telefonica.iot.cygnus.sinks.NGSISink.processRollbackedBatches(NGSISink.java:391),
com.telefonica.iot.cygnus.sinks.NGSISink.process(NGSISink.java:373),
org.apache.flume.sink.DefaultSinkProcessor.process(DefaultSinkProcessor.java:67),
org.apache.flume.SinkRunner$PollingRunner.run(SinkRunner.java:145), java.lang.Thread.run(Thread.java:748)]

Is it possible that the maximum size for a type is 5? (with 5 the size of the namespace is 126)

Can you help me to solve this problem?