[Django]-May not set both `read_only` and `write_only`

by

3👍

✅

Override the __init__() method of the serializer as,

class UserSerializer(serializers.ModelSerializer):
    """A Serizlier class for User """

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        if self.context['some_flag']:
            self.fields['password'].read_only = True
        else:
            self.fields['password'].write_only = True

    class Meta:
        model = models.User
        fields = ('id', 'email', 'phone_number', 'user_type', 'password')
        # extra_kwargs = { 'password': { 'write_only': True} } # remove this
        # read_only_fields = ('password',) # remove this

The some_flag variable is something that you should pass to the serializer either from the password reset view or from the other view

👤JPG

2👍

So extending on the answer of @JPG

The Serializer 

class ProfileSerializer(serializers.ModelSerializer):
    name = serializers.CharField()

def __init__(self, *args, **kwargs):
    super().__init__(*args, **kwargs)
    if 'create_method' in self.context:
        self.fields['name'].write_only = True
    else:
        self.fields['name'].read_only = True

And the view set

class ProfileViewSet(viewsets.ModelViewSet):
    serializer_class = ProfileSerializer

def get_serializer_context(self):

    # Call Parent
    context = super().get_serializer_context()

    # Check If This Is a POST
    if self.request.method == 'POST':
        context['create_method'] = True

    # Handoff
    return context

This will allow name to be written on POST and read only on everything else

👤PythonWolf

0👍

well – normally if you have two endpoints using a similar serializer which needs to differ only with a certain field/functionality you would create a base class and abstract it and only change/modify the parts of it that need to change. Here is what I would do. 

class (serializers.ModelSerializer):
    """A Serizlier class for User """

    class Meta:
        model = models.User
        fields = ('id', 'email', 'phone_number', 'user_type', 'password')
        extra_kwargs = { 'password': { 'read_only': True} }


class UserSerializerForOtherView(UserSerializer):

    class Meta(UserSerializer.Meta):
        extra_kwargs = { 'password': { 'write_only': True} }

Now UserSerializerForOtherView inherits the same behaviour as UserSerializer and you now also have a new serializer should you want to further expand on functionality on this serializer alone.

All you will need to do is tell the other view to use the other serializer.

👤Giannis Katsini

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