deserialization of responses from flask-rest-jsonapi not working

[turekaj]

I currently use flask-rest-jsonapi (https://flask-rest-jsonapi.readthedocs.io/en/latest/) to implement an API. I have defined my schemas and relationshipsusing marshmallow_jsonapi.flask, and the schemas live in another project.

I attempted to create a client which would import the schemas, and utilize the requests library to make http requests to my backend.

MySchema().loads(response.json()) gives back "unknown fields" for things that are not listed in the "attributes" of the jsonapi response. The json response from flask-rest-jsonapi looks correct, and response.json() turns that json into a dict (which is passed to loads)

Am I do something something wrong here?

[multimeric]

From memory, flask-rest-jsonapi adds some metadata, like the jsonapi version, which will cause you to have trouble if you load them via marshmallow-jsonapi.

My hack to solve this for my API is simply deleting the metadata and jsonapi keys: https://github.com/ewels/MegaQC/blob/130cafdb1f74b042385d0645a7acf11e8129f8d7/tests/api/test_api.py#L202-L204

[turekaj]

The error is actually a validation error of my "attributes". Note, I have replaced the actual names of my fields with field_name_1, etc below.

JSON response after deleting ret['meta'] and ret['jsonapi']
{'data': [{'attributes': {
// i see all the fields that were "unknown in the validation here. Some are also here that do not cause validation to puke"
....

marshmallow.exceptions.ValidationError: {0: {'field_name_1': ['Unknown field.'], 'field_name_2': ['Unknown field.'], 'field_name_3': ['Unknown field.'], 'field_name_4': ['Unknown field.'], 'field_name_5': ['Unknown field.'], 'field_name_6': ['Unknown field.']}}

Client:
` r = self._session.get(self._root_url + 'redacted', timeout=self._timeouts, params=payload)
r.raise_for_status()
ret = r.json()
del ret['meta']
del ret['jsonapi']

    data = schemas.RedactedSchema(many=True).load(ret)
    return dat`

Schema:
`
class RedactedSchema(Schema):
class Meta:
ordered = True
type_ = 'redacted'
self_view = 'redacted_detail'
self_view_kwargs = {'id':''}
self_view_many = '_list'

field_name_2 = fields.Integer(dump_only=True, attributes='id')
field_name_4 = fields.UUID(dump_only=True, attributes='uuid')
field_name_d = fields.String()
field_name_c = fields.String(required=True)
field_name_b = fields.String(required=False)
field_name_a = fields.String(required=False)
field_name_9 = fields.String(required=True)
field_name_8 = fields.String(required=True)
field_name_7 = fields.String(allow_none=True)

field_name_3 = fields.String(dump_only=True)
field_name_5 = fields.Integer(dump_only=True)
field_name_1 = fields.DateTime(dump_only=True)
field_name_6= fields.DateTime(dump_only=True)`

[turekaj]

I think I see the issue.

I have fields set as dump_only so that they are really read-only fields. However, I want to share the same schema between my client and server code.

1. do GET request from server. Schema is populated from DB, and then serialized out to jsonapi
2. client gets response back, attempts to de-serialize response into schema, but schema has dump_only=True for fields that were returned and validation fails.

The client only wants read-only access to those fields.

[turekaj]

Replacing dump_only=True with the following 3 parameters gets close to what I want.
required=False, missing=None, allow_none=True,

I believe now the real solution is define two schemas, one for server, one for client, that are identical, except for the field parameters.