Fails when document doesn't contain paths

[Johnlon]

Describe the bug
Fails with an NPE if the OAS is missing a paths section

To Reproduce
Validate a doc without "paths"

Expected behavior
The library should report the OAS as invalid due to lack of a key feature

Additional context
I expect the library is equally lacking in assumptions it makes about other OAS features that might be missing..
A NPE is always a software error.

[Johnlon]

I see there are other similar bugs.
Suggest a complete review of the processing logic with comprehensive tests.

[JFCote]

Hi @Johnlon !
Thanks for the bug report!

You are right, an NPE is always a software error. I will need to check where it comes from because it depends who made the assumption. Either it's swagger-parser or its my code (probably my code!!)

I don't have a lot of time these days + having problems with my eyes/headache so I don't know when I'll be able to look at this but if you have time to create a PR, I will try to look at it quickly.

[gervaisb]

Isn't the role of the open-api-generator-cli (with validate command) to spot the structural issues. The openapi-style-validator is a complement of the first one that can enforce some finer rules and enterprise conventions.

[JFCote]

@gervaisb Yes, at a higher level, you are right. The thing is that we are using swagger-parser to get and object representation of the OpenAPI specification. So the problem is either:

• swagger-parser is not handling the missing path correctly and throw a null pointer exception instead of a clear error message.
• we are having code that think there is always at least one path and we are throwing a null pointer exception. If that's the case, we should check if there is a path and/or throw a meaningful error.

[gervaisb]

Do we have to throw an exception or just no trying to validate the path?

As written by @jmini in #93; "at least one of paths, components or webhooks" is required. One user may want to validate the style of a webhooks only specification.

From a quick test, it seems that OpenAPI#getPaths() returns null when there are no paths (or only the keyword). So we can easily test that case into OpenApiSpecStyleValidator#validateOperations. We only have to decide what to do... IMHO we should skip the validation without raising any errors since the specification may still be valid without paths. Later we can add a stronger test to verify if at least one of paths, components or webhooks is set.

[Johnlon]

Hi any progress? Thanks

[gervaisb]

Hi @Johnlon, thank for your interest.
This should be fixed with this PR; #251

You can build the master branch if you want to test it before the release.

[JFCote]

Since this is fixed in #251 I'm closing this.