[Enhancement] added support for custom type & format mapping

[wing328]

Based on #4931 (credits: @ShoeBoom) but use + as the separator

=========================

Makes it possible to map format.

For example these args can be used to properly map the following:

"foo": {
    "enum": [
        "0",
        "1",
        "2"
    ],
    "type": "integer",
    "format": "byte"
}

generate -i openapi.json -o out -g kotlin --type-mappings integer+byte=kotlin.Byte

By default it would map foo to Int

this is similar to #2730

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cc @OpenAPITools/generator-core-team

[marcelstoer]

generate -i openapi.json -o out -g kotlin --type-mappings integer_byte=kotlin.Byte

Shouldn't it be --type-mappings integer+byte?
...................................................................^...........

[wing328]

@marcelstoer yes, just corrected it. thanks for pointing it out.

[0-sv]

I'm trying to wrap my head around this, hope anyone can help me. Thanks for all the work btw.

Does this imply that I can define my own type like:

url:
  type: string
  format: url
  pattern: $someURLPattern

... and then reference this type by using the type+format syntax? I would love a solution for our workaround with YAML anchors and/or $refs where we defined a custom type.

[marcelstoer]

This is how I use "custom types" but it's unrelated to formats.

common-types.yaml

components:
  schemas:
    Uuid:
      type: string
      description: |
        Canonical textual representation of the 32 hexadecimal (base-16) UUID digits, displayed in five groups
        separated by hyphens, in the form 8-4-4-4-12 for a total of 36 characters
      minLength: 36
      maxLength: 36
      pattern: '^[0-9a-fA-F]{8}\-[0-9a-fA-F]{4}\-[0-9a-fA-F]{4}\-[0-9a-fA-F]{4}\-[0-9a-fA-F]{12}$'

some API contract

...
    Branch:
      type: object
      required:
        - id
      properties:
        id:
          $ref: 'path-to/common-types.yaml#/components/schemas/Uuid'
...