Nifi registry 'getFlowPersistenceProvider' threw exception; nested exception is java.lang.NullPointerException

Hi there,

Maybe some one can help us out. Searching on the web for similar error's doesn't give us a lead on what is going on.

Let me sketch out what is happening. Last week we were cleaning up some old buckets with flows from the nifi-registry manually thru the web gui. At some point we received an error that pointed us the registry logs. Actually didn't see anything there. To test if everything is still working, we tried to commit a change to a versioned flow. Which failed. Unfortunately I don't have the error anymore. So decided to restart the registry hoping that this will help. And now it has gotten worse, the registry isn't starting anymore and is showing the error below.

2024-03-26 09:40:28,551 INFO [NiFi logging handler] org.apache.nifi.registry.StdOut Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'getFlowPersistenceProvider' defined in class path resource [org/apache/nifi/registry/provider/StandardProviderFactory.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.nifi.registry.flow.FlowPersistenceProvider]: Factory method 'getFlowPersistenceProvider' threw exception; nested exception is java.lang.NullPointerException

What is this error trying to tell us? This is our provider config:
<flowPersistenceProvider>

<class>org.apache.nifi.registry.provider.flow.git.GitFlowPersistenceProvider</class>

<property name="Flow Storage Directory">./flow_storage</property>

<property name="Remote To Push">origin</property> <property name="Remote Access User"></property>

<property name="Remote Access Password"></property>

</flowPersistenceProvider>

Any help would be much appreciated.

Thank you in advanced.

Kind regards,

Dave