[fix][elixir] faulty free-form object type spec

[efcasado]

Description

An attempt to fix the issue reported in #21112.

Given the minimal example below

openapi: 3.0.0
info:
  version: 1.0.0
  title: A minimal OpenAPI example
paths:
  /foo:
    post:
      requestBody:
        content:
          application/json:
            schema:
              type: object
        required: true
      responses:
        "200":
          description: Successful operation
        "400":
          description: Invalid operation

version 7.12.0 generates the following code

# NOTE: This file is auto generated by OpenAPI Generator 7.12.0 (https://openapi-generator.tech).
# Do not edit this file manually.

defmodule AMinimalOpenAPIExample.Api.Default do
  @moduledoc """
  API calls for all endpoints tagged `Default`.
  """

  alias AMinimalOpenAPIExample.Connection
  import AMinimalOpenAPIExample.RequestBuilder

  @doc """

  ### Parameters

  - `connection` (AMinimalOpenAPIExample.Connection): Connection to server
  - `body` (map()): 
  - `opts` (keyword): Optional parameters

  ### Returns

  - `{:ok, nil}` on success
  - `{:error, Tesla.Env.t}` on failure
  """
  @spec foo_post(Tesla.Env.client, %{optional(String.t) => }, keyword()) :: {:ok, nil} | {:error, Tesla.Env.t}
  def foo_post(connection, body, _opts \\ []) do
    request =
      %{}
      |> method(:post)
      |> url("/foo")
      |> add_param(:body, :body, body)
      |> Enum.into([])

    connection
    |> Connection.request(request)
    |> evaluate_response([
      {200, false},
      {400, false}
    ])
  end
end

after applying the suggested fix, the generated code looks as follows

# NOTE: This file is auto generated by OpenAPI Generator 7.13.0-SNAPSHOT (https://openapi-generator.tech).
# Do not edit this file manually.

defmodule AMinimalOpenAPIExample.Api.Default do
  @moduledoc """
  API calls for all endpoints tagged `Default`.
  """

  alias AMinimalOpenAPIExample.Connection
  import AMinimalOpenAPIExample.RequestBuilder

  @doc """

  ### Parameters

  - `connection` (AMinimalOpenAPIExample.Connection): Connection to server
  - `body` (%{optional(String.t) => any()}): 
  - `opts` (keyword): Optional parameters

  ### Returns

  - `{:ok, nil}` on success
  - `{:error, Tesla.Env.t}` on failure
  """
  @spec foo_post(Tesla.Env.client, %{optional(String.t) => any()}, keyword()) :: {:ok, nil} | {:error, Tesla.Env.t}
  def foo_post(connection, body, _opts \\ []) do
    request =
      %{}
      |> method(:post)
      |> url("/foo")
      |> add_param(:body, :body, body)
      |> Enum.into([])

    connection
    |> Connection.request(request)
    |> evaluate_response([
      {200, false},
      {400, false}
    ])
  end
end

Note that the inconsistency between the generated types in the @doc and @SPEC attributes has also been addressed.

Again, looking forward to hearing your thoughts @mrmstn! 🙏

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[wing328]

@efcasado thanks for the PR

what about adding test schemas to modules/openapi-generator/src/test/resources/3_0/elixir/petstore-with-fake-endpoints-models-for-testing.yaml to test any type and free form objects?

[efcasado]

@wing328, thanks a lot for your input!

I have just pushed a couple of test schemas to the test OpenAPI spec. I see there was an explicit free-form object already, so I only added an example of an implicit free-form object (ie. additionalProperties is not explicitly set).

[wing328]

lgtm. will get it merged before the upcoming v7.13.0 release due this week

thanks again for the contribution.

[wing328]

when you've time, can you please pm me via Slack?

https://join.slack.com/t/openapi-generator/shared_invite/zt-2wmkn4s8g-n19PJ99Y6Vei74WMUIehQA