[PHP] Bug deserialize default responses as a Model

[ymilin]

Description

I'm generating clients that make use of default responses for other HTTP codes (implying an error). It's defined as a Model (code, message) in definitions in the swagger file.

...
  responses:
    '200':
      description: pet response
      schema:
        type: array
        items:
          $ref: '#/definitions/Pet'
    default:
      description: error payload
      schema:
        $ref: '#/definitions/ErrorModel'
...

After generating the client API with swagger-codegen, when catching an ApiException, the deserialized response object ApiException::responseObject is empty (it is an an instance of ErrorModel as expected, but with no content).

Swagger-codegen version

2.3.0

Swagger declaration file content or url

gist: minimal swagger.json example

Command line used for generation

java -jar bin/swagger-codegen-cli.jar generate -i swagger.json \
  -l php \
  -o build/ \
  --git-user-id "vendor" \
  --git-repo-id "ws-clients" \
  -DpackagePath=.,srcBasePath=lib,variableNamingConvention=camelCase,invokerPackage="MyCie\\Service",apiTests=false,apiDocs=false,modelTests=false,modelDocs=false

Steps to reproduce

With the generated client:

• try to make a request for a non-existing pet
• Expect $e->getResponseObject() to be a fully hydrated instance of ErrorModel
• Got an empty instance of ErrorModel instead

$petApi = new PetApi();

try {
  $pet = $api->getPetById(123);
  ...
} catch (ApiException $e) {
  $errorModel = $e->getResponseObject();
  print_r($errorModel); // empty ErrorModel
}

Suggest a fix/enhancement

I checked the generated code and the bug seem to be located in the catch part of the {{operationId}}WithHttpInfo methods:

try {
    ...
} catch (ApiException $e) {
    switch ($e->getCode()) {
        case 200:
            $data = ObjectSerializer::deserialize(
                $e->getResponseBody(),
                '\MyCie\Service\Model\Pet',
                $e->getResponseHeaders()
            );
            $e->setResponseObject($data);
            break;
        default:
            $data = ObjectSerializer::deserialize(
                $e->getResponseBody(), // <-- works with json_decode($e->getResponseBody())
                '\MyCie\Service\Model\ErrorModel',
                $e->getResponseHeaders()
            );
            $e->setResponseObject($data);
            break;
    }
    throw $e;
}

We can see that there is a specific test for this in the try part of same function in the api.mustache file, line 164

swagger-codegen/modules/swagger-codegen/src/main/resources/php/api.mustache

Lines 163 to 166 in 36f69a0

	$content = $responseBody->getContents();
	if ($returnType !== 'string') {
	$content = json_decode($content);
	}

So a possible fix would be doing something similar when deserializing for ApiException objects.

I can work on a PR for this, as I really need it, but I have no experience with mustache templates and will not be able to test edge cases.

So I would need help for testing my PR.

[kamynina]

any updates?

[HugoMario]

thanks @ymilin , i'll take a time this week to review your PR.

[ymilin]

Hi @kamynina,

I did try and submit a PR for this issue here

Code review (thanks @wing328) showed that my fix is causing issues with primitive type responses and I promised to spend more time on it for a definitive fix.

Since then, I couldn't find more time to come back to it but I'm pretty confident I will be able to somewhere this summer 🤷‍♂️

@HugoMario ,
Thanks, if you have anything to add to the reviews on my PR, I'll try to reply as quickly as I can.

Edit:
As a temporary fix in PHP code using the generated clients, I call ObjectSerializer::deserialize inside a catch block on $e->getResponseHeaders()

try {
    ...
} catch (ApiException $e) {
    $errorModel = ObjectSerializer::deserialize(
        json_decode($e->getResponseBody()),
        \Foo\ErrorModel::class,
        $e->getResponseHeaders()
    );

    // $errorModel is an instance of \Foo\ErrorModel
}