Elixir generator `AnyType` support

[paulbalomiri]

Description

When compiling spec files which contain AnyType, the elixir generator expects a :struct type to be used in decoder.ex.

The generated code fails because no type <PKG>.Model.AnyType exists

Example Generated code found here:

defimpl Poison.Decoder, for: Ory.Model.OAuth2Client do
  import Ory.Deserializer
  def decode(value, options) do
    value
    |> deserialize(:jwks, :struct, Ory.Model.AnyType, options)
    |> deserialize(:metadata, :struct, Ory.Model.AnyType, options)
  end
end

openapi-generator version

6.0.3 to latest in main branch

Related issues/PRs

The proposed fix will reference this issue and builds on the latest work by @halostatue.

• Elixir Generator generates code with lots of warnings #12731
• Further Elixir Client Improvements #12775

I also include the related elixir issues from #12731.

• [REQ] Specify ExDoc dependency for Elixir #12484
• [REQ][Elixir] Generate ExUnit tests #4011
  Still there is no elixir test suite
• [BUG][ELIXIR] Date format not generating correct code, and date-time format not generating code #8804
• Allow the baseUrl of elixir APIs to be overridden #12268

Suggest a fix/enhancement

When work on my branch is finished I intend to submit a PR

[paulbalomiri]

I'm referring here to the discussion in the PR, which is better placed here, and in separate (future) related issues.

So there are 2 bugs here, and potentially a discussion

1. recreate a PR branch by cherry picking:
   • for the AnyType specific changes (mapping to the bare json decoded value)

This is a feature addition, but without it this is a bug, as the non-existing AnyType is used (as <PKG>.Model.AnyType ) in the generated code:

https://github.com/ory/sdk/blob/958314d130922ad6f20f439b5230141a832231a5/clients/kratos/elixir/lib/ory/model/error_authenticator_assurance_level_not_satisfied.ex#L36-L41

• change the header field name handling using some form of Kernel.to_string/1, as Tesla.put_header/3 (doc) expects a binary() not an atom() as key argument, as is proposed here:
  

  openapi-generator/samples/client/petstore/elixir/lib/openapi_petstore/request_builder.ex

  Lines 105 to 108 in f0625b8

  	def add_param(request, :headers, key, value) do
  	Tesla.put_header(request, to_string(key), value)
  	end

2. create a separate issue for the tesla/piping part, which is more a discussion whether there is a place for this approach in openapi-generator, in an additional generator, or in a separate custom template generarator repo.

[paulbalomiri]

@mrmstn, @halostatue so the two bugs in one PR, discussion separately is ok?

[halostatue]

I think that the change of approach to fixed struct from piping should probably be a separate PR, as I’m not convinced that it’s a good change, personally. I generally treat Tesla.Env.t() as opaque.

[paulbalomiri]

Will contribute this this weekend. [personal urgency]

[parkerduckworth]

Hello 👋 any update on this, by any chance? I'm running into the same issue with this elixir kratos client

[paulbalomiri]

Hi @parkerduckworth ,
No update for this issue, sorry. It's still on my "sonnish" list :)
In the meantime I'm using the bugfix_elixir branch from my fork from &deps/0 in mix.exs like so:

{:ory_hydra, github: "paulbalomiri/ory_sdk", sparse: "clients/hydra/elixir/", tag: "bugfix_elixir"},
{:ory_kratos, github: "paulbalomiri/ory_sdk", sparse: "clients/kratos/elixir/", tag: "bugfix_elixir"},

You could fork yourself, or use it directly, but it's not production grade.

[mrmstn]

Hi everyone, I was able to get some spare time to resolve this issue.

Thanks to everyone involved in this, specially @paulbalomiri for bringing this issue up and filling a draft for the issue. Also, a special thanks to @halostatue for the reviews and discussions, I highly appreciate it.

The fix will be shipped in version 6.3.0.