Use WireMock for Dropbox integration tests

[jamesnetherton]

Not sure if it is possible or not but it'd be worth investigating to see if we have the tests run on the CI build without requiring real credentials.

[djcoleman]

At first I thought this was going to be a fairly quick task based on the Geocoder tests, but I found myself heading down a warren of rabbit holes with this.

In order to test the Dropbox extension with Wiremock, the wiremock server URL must be passed to the dropbox client within the Camel component.

I first tried creating an instance of DbxClientV2 (the client supplied by the Dropbox SDK), but it had limited support for passing in a new host - I had to access a private constructor via reflection to be able to pass in the Wiremock URL as well as the credentials.

The next issue was setting the client in the Camel component. I had to create a sub-class of the DropboxComponent and register that in place of the original. The sub-class overrode the createEndpoint method that first called the parent implementation and then accessed the DropboxConfiguration object, to which I could pass the DbxClientV2 object.

However, this still did not work as the DbxClientV2 object doesn't handle port numbers - it only expects hostnames, so URL creation fails.

I don't know if the Wiremock proxy support can be used to create an alias that can be used instead of localhost:{randomPort}, but I've spent more time than I'd intended on this already.

[ppalaga]

Thanks for your patient investigation, @djcoleman !

We should perhaps try our luck asking the Dropbox client team for a proper base URI support? https://github.com/dropbox/dropbox-sdk-java/issues

[djcoleman]

I found a question from 2019 on dropboxforum.com requesting WireMock support. The responder acknowledged the problem and promised to submit a feature request, although he didn't make any commitments to implementing it.

I don't see any tickets in the dropbox-sdk-java issues list already though, so I can submit a request myself and see if anything happens.

[ppalaga]

@djcoleman could you please paste the Dropbox issue URL here?

[djcoleman]

Here it is: dropbox/dropbox-sdk-java#487