Reference entry point for OpenAPI-compatible generated clients.

Tesla does not parse OpenAPI documents or generate operation modules. It provides value objects and middleware hooks that generated clients can use after they have already interpreted the OpenAPI document.

Parameter Locations

Static Metadata And Dynamic Values

Generated clients should keep OpenAPI parameter definitions as module attributes and pass only request values at runtime:

defmodule MyApi.Operation.GetItem.Path do
  @path_template Tesla.OpenAPI.PathTemplate.new!("/items/{id}")

  @path_params Tesla.OpenAPI.PathParams.new!([
                 Tesla.OpenAPI.PathParam.new!("id")
               ])

  def path_template, do: @path_template
  def path_params, do: @path_params
end

defmodule MyApi.Operation.GetItem.Query do
  @query_params Tesla.OpenAPI.QueryParams.new!([
                  Tesla.OpenAPI.QueryParam.new!("filter")
                ])

  def query_params, do: @query_params
end

defmodule MyApi.Operation.GetItem do
  alias MyApi.Operation.GetItem.{Path, Query}

  @private Tesla.OpenAPI.merge_private([
             Tesla.OpenAPI.PathTemplate.put_private(Path.path_template()),
             Tesla.OpenAPI.PathParams.put_private(Path.path_params()),
             Tesla.OpenAPI.QueryParams.put_private(Query.query_params())
           ])
end

Path and query parameter collections are placed in Tesla.Env.private/0 because their middleware serializes them into the request URL. Header and cookie parameter collections are applied before the request enters the middleware stack and produce raw header tuples.

Response Wrappers

Generated clients can define a local response module with Tesla.OpenAPI.Response:

defmodule MyApi.Response do
  use Tesla.OpenAPI.Response
end

Field Mapping

in chooses the Tesla API. It is not passed as an option to the value objects. style, explode, and allowReserved become :style, :explode, and :allow_reserved options where the corresponding parameter location supports them.

See Working with OpenAPI parameters for a generated-operation walkthrough, or the OpenAPI Cheat Sheet for quick lookup while implementing generated clients.