[BUG][RUST-SERVER] doesn't produce compilable code with simple example API

Description

I have written a simple, sample API, and rust-server generates code which doesn't compile.

Full cargo build output here, but there are three problems:

• models::models::models::TYPE used instead of models::TYPE, e.g.

error[E0603]: module `models` is private
  --> src/lib.rs:77:35
   |
77 |     fn a_post(&self, arg: models::models::models::Arg) -> Box<Future<Item=APostResponse, Error=ApiError>>;

• wrong variable used to log parameter e.g.

error[E0277]: `()` doesn't implement `std::fmt::Display`
   --> src/server/mod.rs:210:173
    |
210 |                         Err(e) => return Box::new(future::ok(Response::new().with_status(StatusCode::BadRequest).with_body(format!("Couldn't parse path parameter arg: {}", e)))),

In this case , e) should be , param_arg)

• invalid FromStr implementation e.g.

error[E0308]: match arms have incompatible types
  --> src/models.rs:42:9
   |
42 | /         match s {
43 | |             "0" => Ok(Arg::_0),
   | |                    ----------- match arm with an incompatible type
44 | |             "1" => Ok(Arg::_1),
45 | |             "2" => Ok(Arg::_2),
46 | |             _ => Err(()),
47 | |         }
   | |_________^ expected enum `std::result::Result`, found struct `models::Ok`
   |
   = note: expected type `std::result::Result<models::Arg, ()>`
              found type `models::Ok`

This might be a little harsh! The problem is that Ok here is models::Ok not Result::Ok.

Commit fixing the compilation errors here.

There are also similar errors with the client and server examples, plus also an extraneous use swagger::auth::Authorization; causing the server example to fail to compile:

error: unused import: `swagger::auth::Authorization`
  --> examples/server_lib/mod.rs:16:5
   |
16 | use swagger::auth::Authorization;
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: `-D unused-imports` implied by `-D warnings`

Fixes for the client and server examples are in this commit.

openapi-generator version

4.0.0-SNAPSHOT

Using container openapitools/openapi-generator-cli:latest

OpenAPI declaration file content or url

openapi.yaml

Command line used for generation

docker run --rm \
           -v ~/openapi-generator-rust-server-test/openapi_client:/local \
           openapitools/openapi-generator-cli \
           generate \
           -g rust-server \
           -i /local/openapi.yaml \
           -o /local

Steps to reproduce

cd ~
git clone https://github.com/piersfinlayson/openapi-generator-rust-server-test
cd openapi-generator-rust-server-test
docker pull openapitools/openapi-generator-cli
docker run --rm \
           -v ~/openapi-generator-rust-server-test/openapi_client:/local \
           openapitools/openapi-generator-cli \
           generate \
           -g rust-server \
           -i /local/openapi.yaml \
           -o /local
cd openapi_client
cargo build
cargo build --example client
cargo build --example server

Related issues/PRs

None that I can see

Suggest a fix

See above