NIFI-14029 - BitBucket Registry Client

[pvillard31]

Summary

NIFI-14029 - BitBucket Registry Client

Adding an implementation of the Registry Client to integrate with BitBucket. For reference, APIs are described here:

https://developer.atlassian.com/cloud/bitbucket/rest/intro

In addition to the implementation itself, two bugs are fixed:

• NPE in case the initialization fails for some reason. In this case, we already called clientInitialized.set(true) and this caused to always have the directory exclusion filter being null. This is now fixed.
• NPE in the deregisterFlow method. This happens when we start version control and for some reason, something fails after the file has been committed. In that case, we delete the content in the repo. Because we didn't populate the snapshot metadata, this was causing a NPE.

java.lang.NullPointerException: Cannot invoke "org.apache.nifi.registry.flow.RegisteredFlowSnapshotMetadata.setBucketIdentifier(String)" because "snapshotMetadata" is null
	at org.apache.nifi.registry.flow.git.AbstractGitFlowRegistryClient.updateBucketReferences(AbstractGitFlowRegistryClient.java:548)
	at org.apache.nifi.registry.flow.git.AbstractGitFlowRegistryClient.deregisterFlow(AbstractGitFlowRegistryClient.java:255)

Regarding the implementation itself. Three authentication methods are supported:

• Basic Auth with Username and App Password
• OAuth 2.0 - I tested the Client Credentials Flow with OAuth Consumers. Note that the endpoint to configure in the controller service for OAuth is https://bitbucket.org/site/oauth2/access_token. It is important to also note that, when using the Client Credentials flow, the permissions/scopes set at the OAuth Consumer level in the BitBucket Admin UI are ignored and it will inherit the permissions of the owner of the OAuth Consumer. This is quite misleading...
• Access Token - I have not tested this option as this is a paid option of BitBucket.

Tracking

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• Apache NiFi Jira issue created

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Build

• Build completed using mvn clean install -P contrib-check
  • JDK 21

Licensing

• New dependencies are compatible with the Apache License 2.0 according to the License Policy
• New dependencies are documented in applicable LICENSE and NOTICE files

Documentation

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