[PHP] - Add FormDataProcessor to handle nested ModelInterface data

[jtreminio]

When a request has nested models, and one or more of these models has binary data property (file upload), the PHP generators fail to correctly create a valid formdata array.

This is because only the top-level model/data is checked for binary data properties.

Given:

paths:
  '/pet/{petId}/uploadImageFullFormDataNested':
    post:
      tags:
        - pet
      summary: uploads an image attached to a Pet object as formdata
      description: ''
      operationId: uploadImageFullFormDataNested
      parameters:
        - name: petId
          in: path
          description: ID of pet to update
          required: true
          schema:
            type: integer
            format: int64
      responses:
        '200':
          description: successful operation
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiResponse'
      security:
        - petstore_auth:
            - 'write:pets'
            - 'read:pets'
      requestBody:
        content:
          multipart/form-data:
            schema:
              type: object
              properties:
                pet:
                  $ref: '#/components/schemas/PetWithFile'

The generated API method signature looks like:

public function uploadImageFullFormDataNested($pet_id, $pet = null, string $contentType = self::contentTypes['uploadImageFullFormDataNested'][0])

Normally all properties in a formdata object would be listed individually in the signature, but in this case it comes via $pet. The existing method of creating formData array will not work because it expects any file upload data to be in the root-level (ie, listed in the method signature), and not nested within an object.

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[jtreminio]

Pinging maintainers:

@jebentier (2017/07), @dkarlovi (2017/07), @mandrean (2017/08), @jfastnacht (2017/09), @ybelenko (2018/07), @renepardon (2018/12)

[wing328]

local tests failed:

PHPUnit 9.6.22 by Sebastian Bergmann and contributors.

...............................................................  63 / 240 ( 26%)
............................................................... 126 / 240 ( 52%)
............................................................... 189 / 240 ( 78%)
.........................F.........................             240 / 240 (100%)

Time: 00:01.258, Memory: 14.00 MB

There was 1 failure:

1) OpenAPI\Client\PetApiTest::testObjectInFormData
Failed asserting that '--3dd13ca2951017f248a1983cdc040c207fc2ed35\n
Content-Disposition: form-data; name="id"\n
Content-Length: 5\n
\n
12345\n
--3dd13ca2951017f248a1983cdc040c207fc2ed35\n
Content-Disposition: form-data; name="category[id]"\n
Content-Length: 5\n
\n
12345\n
--3dd13ca2951017f248a1983cdc040c207fc2ed35\n
Content-Disposition: form-data; name="category[name]"\n
Content-Length: 13\n
\n
Category_Name\n
--3dd13ca2951017f248a1983cdc040c207fc2ed35\n
Content-Disposition: form-data; name="name"\n
Content-Length: 11\n
\n
My pet name\n
--3dd13ca2951017f248a1983cdc040c207fc2ed35\n
Content-Disposition: form-data; name="photo_urls[0]"\n
Content-Length: 33\n
\n
https://example.com/picture_1.jpg\n
--3dd13ca2951017f248a1983cdc040c207fc2ed35\n
Content-Disposition: form-data; name="photo_urls[1]"\n
Content-Length: 33\n
\n
https://example.com/picture_2.jpg\n
--3dd13ca2951017f248a1983cdc040c207fc2ed35\n
Content-Disposition: form-data; name="tags[0][id]"\n
Content-Length: 5\n
\n
12345\n
--3dd13ca2951017f248a1983cdc040c207fc2ed35\n
Content-Disposition: form-data; name="tags[0][name]"\n
Content-Length: 5\n
\n
tag_1\n
--3dd13ca2951017f248a1983cdc040c207fc2ed35\n
Content-Disposition: form-data; name="tags[1][id]"\n
Content-Length: 5\n
\n
98765\n
--3dd13ca2951017f248a1983cdc040c207fc2ed35\n
Content-Disposition: form-data; name="tags[1][name]"\n
Content-Length: 5\n
\n
tag_2\n
--3dd13ca2951017f248a1983cdc040c207fc2ed35\n
Content-Disposition: form-data; name="status"\n
Content-Length: 9\n
\n
available\n
--3dd13ca2951017f248a1983cdc040c207fc2ed35\n
Content-Disposition: form-data; name="file"\n
Content-Length: 16\n
\n
Resource id #460\n
--3dd13ca2951017f248a1983cdc040c207fc2ed35\n
Content-Disposition: form-data; name="multiple_files[0]"\n
Content-Length: 16\n
\n
Resource id #461\n
--3dd13ca2951017f248a1983cdc040c207fc2ed35\n
Content-Disposition: form-data; name="multiple_files[1]"\n
Content-Length: 16\n
\n
Resource id #462\n
--3dd13ca2951017f248a1983cdc040c207fc2ed35--\n
' contains "Content-Disposition: form-data; name="photoUrls[0]"
Content-Length: 33

https://example.com/picture_1.jpg".

/mnt/c/Users/wing3/Code/openapi-generator3/samples/client/petstore/php/OpenAPIClient-php/tests/PetApiTest.php:446
/mnt/c/Users/wing3/Code/openapi-generator3/samples/client/petstore/php/OpenAPIClient-php/tests/PetApiTest.php:420

FAILURES!
Tests: 240, Assertions: 416, Failures: 1.

can you please take a look when you've time?

to run the test, execute mvn integration-test -f samples/client/petstore/php/OpenAPIClient-php/pom.xml

you will need to run a local petstore server: https://github.com/OpenAPITools/openapi-generator/wiki/Integration-Tests#how-to-add-integration-tests-for-new-petstore-samples