How to make a PATCH request using DJANGO REST framework

Question

I am not very experience with Django REST framework and have been trying out many things but can not make my PATCH request work.

I have a Model serializer. This is

Answer 1

Make sure that you have "PATCH" in http_method_names. Alternatively you can write it like this:

@property
def allowed_methods(self):
    """
    Return the list of allowed HTTP methods, uppercased.
    """
    self.http_method_names.append("patch")
    return [method.upper() for method in self.http_method_names
            if hasattr(self, method)]

As stated in documentation:

By default, serializers must be passed values for all required fields or they will raise validation errors. You can use the partial argument in order to allow partial updates.

Override update method in your view:

def update(self, request, *args, **kwargs):
    instance = self.get_object()
    serializer = TimeSerializer(instance, data=request.data, partial=True)
    serializer.is_valid(raise_exception=True)
    serializer.save(customer_id=customer, **serializer.validated_data)
    return Response(serializer.validated_data)

Or just override method partial_update in your view:

def partial_update(self, request, *args, **kwargs):
    kwargs['partial'] = True
    return self.update(request, *args, **kwargs)

Serializer calls update method of ModelSerializer(see sources):

def update(self, instance, validated_data):
    raise_errors_on_nested_writes('update', self, validated_data)

    # Simply set each attribute on the instance, and then save it.
    # Note that unlike `.create()` we don't need to treat many-to-many
    # relationships as being a special case. During updates we already
    # have an instance pk for the relationships to be associated with.
    for attr, value in validated_data.items():
        setattr(instance, attr, value)
    instance.save()

    return instance

Update pushes the validated_data values to the given instance. Note that update should not assume all the fields are available. This helps to deal with partial updates (PATCH requests).