API with an unknown path should return an error

[nopcoder]

Currently lakeFS register openapi handlers and handle all specific routes.
In case of a call to /api/v1/test, the unknown path under the API prefix, the mux will serve the request by the UI handler and return a valid HTML (UI) page.

The expected behaviour is to return a non-2xx status code with JSON error - prefered the internal error format, so the developer will handle an error and not fail to parse the response in case of a bad API call.

[nopcoder]

The above bug also affects hadoop-lakefs when the lakefs api endpoint is configured currently.
Example: https://prod.lakefs.dev/api/v/
No handler registered to handle this call and it falls to the default, which is UI handler that returns html with 2xx.

[codeaucafe]

Hey @nopcoder I haven't dug into the code specifics yet but I am hoping to take this up if that is fine, ok? Thanks in advance!

Best,
David D

[nopcoder]

sure, thanks!

[nopcoder]

@DataDavD let me know if you have any questions or need help in this one.

[codeaucafe]

Ok great, thank you @nopcoder. I'll take a close look this weekend and return with any questions I'll probably have.

Thanks again!!!!
David

[codeaucafe]

hey @nopcoder just wanted to give you an update. I was able to take a look at the code and believe I understand the specific issue at hand. I intend to look much more closely tomorrow or the following day now that I pinpointed the code at issue; I will most likely send you some clarifying questions then.

Thank you,
dd

[nopcoder]

Thanks for the updates @DataDavD , here for anything that will help you get this one moving.

[codeaucafe]

hey @nopcoder I am assuming the issue is centered around this line of code. I've been having a little trouble reading through the code because a number of objects/types like HandlerFromMuxWithBaseURL show as unresolved refs and I believe are causing my make build to fail with error error generating code: error generating Go handlers for Paths: error generating inlined spec: template: inline.tmpl:5:8: executing "inline.tmpl" at <.>: range can't iterate over . Do you know what the issue is or does this even prevent correcting it, or is just an annoyance for now?

Also to clarify, for any route past /api/v1 return json 401 error instead of UIHandler, correct?

[nopcoder]

Hi @DataDavD, make build should run go generate and fill the missing parts - the specific one is lakefs.gen.go which includes the openapi generated code.
Verify that you have Go 1.16 and try to run go generate command found in serve.go - maybe it will have more information about the source of the error.

The main issue is any route under /api/v1 (ex: /avi/v1/unknown) will continue to fall to the UI handler and serve the UI html with status code 200.
We would like to return the default error with 500 with writeError so the caller will identify there is an issue.

[codeaucafe]

Ahh ok that makes sense; maybe my issue was maybe go 1.15 related, not totally sure though.

Thanks for confirming the issue; I thought that was it but want to verify before I start writing code to handle that. Thank you!!!!