Refactor Checks to Operate on the Context Object

[maxim-tschumak]

After implementing the initial support for OpenAPI3 we have to adjust the check implementations. Instead of operating on the Swagger object, the checks have to use the Context object. Doing this, the checks become universal - applicable against Swagger2 and OpenAPI3 specifications.

Acceptance Criteria:

1. The following checks are refactored to use the Context object
2. Minimal specifications are used in the tests

List of Rules to be refactored

Zalando (API Guidelines)

Done

• JsonProblemAsDefaultResponseRule
• UseSpecificHttpStatusCodes
• AvoidTrailingSlashesRule
• CommonFieldTypesRule
• EverySecondPathLevelParameterRule
• MediaTypesRule 🎋 Branch 🔍 Pull Request
• AvoidLinkHeadersRule 🎋 Branch 🔍 Pull Request
• PluralizeResourceNamesRule

High priority list (please migrate these first)

• FormatForNumbersRule
• LimitNumberOfResourcesRule (PR)
• PluralizeNamesForArraysRule (PR)
• QueryParameterCollectionFormatRule (PR)
• SecureWithOAuth2Rule (PR)
• SuccessResponseAsJsonObjectRule (PR)
• ExtensibleEnumRule (PR)

Lower priority list

• Use429HeaderForRateLimitRule (PR)
• SnakeCaseInPropNameRule (PR)
• SnakeCaseForQueryParamsRule (PR)
• ApiMetainformationRule (PR)
• PascalCaseHttpHeadersRule (PR)
• LimitNumberOfSubresourcesRule (PR)
• VersionInInfoSectionRule (PR)
• NestedPathsMayBeRootPathsRule (PR)
• NoVersionInUriRule (PR)
• KebabCaseInPathSegmentsRule (PR)

Nic-to-have, less important checks will be refactored as part of #834

[ghost]

Started

on branch 714-use-context-object.

[ghost]

NoUnusedDefinitionsCheck

I wanted to create a PR for a 2nd rule today, but that did not happen.

I am stuck with one case that fails and need to figure it out.

The branch in GIT is: 714-rules-to-oas--NoUnusedDefinitionsRule

Next steps

• Make this test pass:
  • de.zalando.zally.rule.zally.NoUnusedDefinitionsRule2Test#the SPP API causes no violations
• Remove those files
  • NoUnusedDefinitionsRule2
  • NoUnusedDefinitionsRule2Test
• Rename those files
  • NoUnusedDefinitionsRule2 to NoUnusedDefinitionsRule
  • NoUnusedDefinitionsRule2Test to NoUnusedDefinitionsRuleTest
• Adjust the CLI's integration test (GO)

[roxspring]

Intrigued to notice "SecureAllEndpointsWithScopesRule (currently not used in production)"... is there an issue raised with known problems for this rule?

Seems a shame that the two Zally installations I know of (yours and mine) currently both disable this rule!