[BUG] Generates List<<List<SomeGet$Response>> instead of List<SomeGet$Response>

[anasJasim]

Describe the bug
The code generation process for the OpenAPI Swagger Dart library is producing incorrect output. Instead of generating a response type of List<ItemsGet$Response>, the code generator is generating List<List<ItemsGet$Response>>.

Generated output
File: openapi.swagger.dart

abstract class Openapi extends ChopperService {
    @Get(path: '/items')
    Future<chopper.Response<List<ItemsGet$Response>>> _itemsGet(
        {@Query('tenantUnitId') required int? tenantUnitId});
}
// ...
typedef ItemsGet$Response = List<ItemsGet$Response$Item>;

Expected output
File: openapi.swagger.dart

abstract class Openapi extends ChopperService {
    @Get(path: '/items')
    Future<chopper.Response<ItemsGet$Response>> _itemsGet(
        {@Query('tenantUnitId') required int? tenantUnitId});
}
// ...
typedef ItemsGet$Response = List<ItemsGet$Response$Item>;

Swagger specification link
Link to swagger/OpenApi documentation

build.yaml

targets:
  $default:
    builders:
      swagger_dart_code_generator:
        options:
          input_folder: "lib/openapi/swaggers/"
          output_folder: "lib/openapi/generated_code/"
          input_urls:
            - url: "http://127.0.0.1:3001/openapi.json"

Library version used:
chopper: ^6.1.1
json_annotation: ^4.8.0

build_runner: ^2.3.3
chopper_generator: ^6.0.0
json_serializable: ^6.6.1
swagger_dart_code_generator: ^2.10.4

[dJani97]

I have the same issue with a similar schema, mine also contains the same structure:

"schema": {
  "type": "array",
  "items": {
    "type": "object",

@anasJasim did you find any solution?

I think one possible way of fixing it is to rewrite your schema like so:

"schema": {
  "$ref": "#/components/schemas/SomeSchema"
}

These types of schemas work well for me with the generator. But this is of course not possible on a large scale, and an unnecessary manual step.

My framework & lib version:
Flutter: 3.29.0
swagger_dart_code_generator: ^3.0.1

[anasJasim]

Unfortunately @dJani97 I haven't found a clean solution yet. But business must go on haha, so here is my hacky solution:

# Items
- url: "/items"
  method: post
  overridden_value: "dynamic"
- url: "/items"
  method: get
  overridden_value: "dynamic"
# ...

Add above to build.yaml. When you do so you also encounter another issue and for that I have created post-swagger-bug-fix.sh

#!/bin/bash

file="./lib/src/utils/openapi/generated_code/openapi.swagger.dart"

search_string="generatedMapping.putIfAbsent(\$Dynamic, () => \$Dynamic.fromJsonFactory);"

grep -v "$search_string" "$file" > "$file.tmp" && mv "$file.tmp" "$file"

echo "Lines containing '$search_string' have been removed in '$file'."

Your solution might be cleaner, but it wouldn't work if you use an automated OpenAPI generator in the backend.

[flowhorn]

Hey, I made a PR which should fix this issue, removed one .asList() in the generation code:

#792

You can try it out using:

  swagger_dart_code_generator:
    git: https://github.com/flowhorn/swagger-dart-code-generator.git

Apparently this doesn't fully work for me, as there is still some issue then with the json_decoder which requires some adjustments.