[#443] Update ResponseValidator to support nullable and required

[lukecivantos]

Problem

Currently running into issues similar to what is described in this issue. When I include nullable or required for response headers it errors out because the response validator checks for .nil?.

Solution

In this PR I add changes to validate_headers! checking for required and nullable. And changing the error return appropriately. I also added tests as well as a subsection to the readme.

Notably when I ran ./ci/build.sh and ./ci/test.sh everything passes, but some of the generated files changed a bit. Happy to change accordingly if there are any recommendations.

This concerns this parts of the Open API Specification:

• OpenAPI Specs – Describing Parameters (section on nullable + required)
• OpenAPI Specs – Describing Responses (section on headers)

The changes I made are compatible with:

• OAS2 – I didn't see anything about nullable in OAS2, but this change shouldn't impact current OAS2 users
• OAS3
• OAS3.1

Related Issues

Ability to make response headers not mandatory: #443

Checklist

• Added tests
• Changelog updated
• Added documentation to README.md

Steps to Test or Reproduce

Can see the line causing the issue here.

When I run ./ci/test.sh everything works

To replicate can add a nullable and optional header response here.

[jtannas]

I like it :) @BookOfGreg approve once the package-lock is sorted out?

[jtannas]

These package-lock changes seem unrelated to the header changes.
Accidental inclusion?

[lukecivantos]

Thanks for the review! Yeah they appeared when I ran ./ci/build.sh – wasn't sure if I should keep or remove so I included. Just removed though 👍🏼

[lukecivantos]

Hey @BookOfGreg – wanted to follow up and see if you had gotten a chance to take a look at the changes here. Let me know if there's anything I can help clarify – thanks!

[lukecivantos]

just following up here to see if there were any updates or if you had a chance to look @BookOfGreg cc @jtannas – thanks!

[lukecivantos]

Hey @BookOfGreg & @jtannas – wanted to follow up to see if you could potentially review this week. Thanks!

[lukecivantos]

Hey @BookOfGreg just wanted to follow up on getting a review. We're hoping to remove the monkey patch we're currently using as soon as possible. Let me know if there are any lingering questions.

cc @jtannas

[jtannas]

@lukecivantos Sorry for the slow reply. I've been focusing on other things for the past few months.

The changes look good 🙂 If you could merge the latest master and add an accompanying changelog note I'd be happy to merge this and release it in 2.7

[lukecivantos]

Hey @jtannas sorry I missed this message – is it too late to include in 2.7? I could merge the latest master today

[lukecivantos]

@jtannas Just merged the latest master and added the update to the changelog. If there are any other changes needed to get this into the 2.7 release I can make them today.

[jtannas]

I've already tagged the 2.7 release commit. I'll push 2.7 out tonight and up the 2.8 process.

[lukecivantos]

Sounds good – let me know if there are any additional changes I need to make