Add documentation about supporting both add and create operations for many=False (one-to-many) fields

[dmugtasimov]

Having it configured:

    organization = NestedField(
        OrganizationSerializer,
        accept_pk=True,
        create_ops=[ADD, CREATE],
        update_ops=[])

I am able to assign existing organization. But when I try to create one with either:

    "organization": {
        "create": {
            "name": "mvEkjEwIWsmcvjjHGQjzlEUOThKoCQmnrGyiVmfZVAkLGUwYbnnVWhBBhxKGXsqPvRDrgJfzHxsWjlNXcVslnKMpiVhZMcnnkBPkblpudePVSppkijXTRNrpBdPqlVOmUHDuPpXMdtVIiGUosYAAxgVvCsRLfYXvUarTBbsUdTdyabAubtJRYhZIGYglkjeUlJXBpfmreroReJUIptRTuHjcaGMjpAyJIqOmmBQsBVTpaNSxUGfmbKqYQjFlDbR",
            "organizationType": 1,
            "npi": "",
            "addressLine1": "xLCqpNCSitljQIPSvASsywcBdDtNbgBHxaOkpZSEyosvuoYAwUxcZmIkTXWmaJfpMXmvLoHFnxYMFZTjRpWjfUXuXwJXfzitzPBoMjzGhXaevMzUtkAVXrwQ",
            "addressLine2": "",
            "city": "YtdAFiKHETbFrVnILLqaeWvQUpdNjcBhvNHnfLdAdVRrfUnqMpmpSPxMSoINVDkTnSohIZbpwhGcnRecVxzYjkHThgXdyDvSbDzBrFlhXSyNYsMhSOyzSyZIFeZRvzwbldcEExxQEitwpaolDmNZlUtoXRBSyYmKrwNIzqfoRKqqFNIEnTKLNScLpxdvQvRctTEkNYiC",
            "state": 3,
            "country": 19,
            "zipCode": "AjmDiXUCBE",
            "phone": "rBRWNhYuWlMYqtz"
        }
    }

or

    "organization": {
            "name": "mvEkjEwIWsmcvjjHGQjzlEUOThKoCQmnrGyiVmfZVAkLGUwYbnnVWhBBhxKGXsqPvRDrgJfzHxsWjlNXcVslnKMpiVhZMcnnkBPkblpudePVSppkijXTRNrpBdPqlVOmUHDuPpXMdtVIiGUosYAAxgVvCsRLfYXvUarTBbsUdTdyabAubtJRYhZIGYglkjeUlJXBpfmreroReJUIptRTuHjcaGMjpAyJIqOmmBQsBVTpaNSxUGfmbKqYQjFlDbR",
            "organizationType": 1,
            "npi": "",
            "addressLine1": "xLCqpNCSitljQIPSvASsywcBdDtNbgBHxaOkpZSEyosvuoYAwUxcZmIkTXWmaJfpMXmvLoHFnxYMFZTjRpWjfUXuXwJXfzitzPBoMjzGhXaevMzUtkAVXrwQ",
            "addressLine2": "",
            "city": "YtdAFiKHETbFrVnILLqaeWvQUpdNjcBhvNHnfLdAdVRrfUnqMpmpSPxMSoINVDkTnSohIZbpwhGcnRecVxzYjkHThgXdyDvSbDzBrFlhXSyNYsMhSOyzSyZIFeZRvzwbldcEExxQEitwpaolDmNZlUtoXRBSyYmKrwNIzqfoRKqqFNIEnTKLNScLpxdvQvRctTEkNYiC",
            "state": 3,
            "country": 19,
            "zipCode": "AjmDiXUCBE",
            "phone": "rBRWNhYuWlMYqtz"
    }

I get HTTP400 {"organization":["Incorrect type. Expected pk value, received dict."]}

On the other hand without accept_pk=True,. I get HTTP400 {"organization":{"nonFieldErrors":["Invalid data. Expected a dictionary, but got int."]}} with "organization":17. Or I HTTP400 {"organization":{"addressLine1":["This field is required."],"city":["This field is required."],"zipCode":["This field is required."],"phone":["This field is required."],"name":["This field is required."],"organizationType":["This field is required."],"country":["This field is required."]}} with "organization":{"add":[18]}

[dmugtasimov]

found this in the source code:

    BaseClass = BaseReplaceableNestedField if accept_pk \
        else BaseWritableNestedField

looks like add and create are not supported simultaneously for the same foreign key. It is true, please, state it explicitly in the documentation. But better fix it to be consistent with many-to-many relations which support add and create operations on the same field simultaneously.

[yezyilomo]

You don't need create_ops and update_ops kwargs for a foreign key relation.

organization = NestedField(OrganizationSerializer, accept_pk=True)

create_ops and update_ops kwargs are used along with many=True

[dmugtasimov]

@yezyilomo thank you. Is it still going to accept dict (JSON object) to create an organization? Or I have to choose either pk or creation a new object?

[yezyilomo]

@yezyilomo thank you. Is it still going to accept dict (JSON object) to create an organization? Or I have to choose either pk or creation a new object?

With create_ops and update_ops You can use both pk and create new object. Check https://django-restql.yezyilomo.com/mutating_data/#using-nestedfield-with-create_ops-and-update_ops-kwargs for more details about using create_ops and update_ops.