How to use django-multiselect field in postman?

Question

I am using pip module MultiSelectField Here is my model

SALES_CHANNEL = [
    ('retailer', 'Retailer'),
    ('wholesaler', 'Wholesaler'),
    ('consumer', 'Consumer'),
    ('distributor', 'Distributor'),
    ('online', 'Online')
]

class ProductModel(basemodel.BaseModel):
    name = models.CharField(max_length=200)
    mrp = models.DecimalField(
        max_digits=10, decimal_places=2,
        null=True, blank=True
    )
    selling_price = models.DecimalField(
        max_digits=10, decimal_places=2,
        null=True, blank=True
    )
    upc = models.CharField(max_length=30, null=True, blank=True)
    dimensions = models.CharField(max_length=200, null=True, blank=True)
    weight = models.CharField(max_length=200, null=True, blank=True)
    sku = models.CharField(max_length=200, unique=True)
    product_type = models.CharField(
        max_length=30, choices=PRODUCT_TYPE, default='goods'
    )
    sales_channel = MultiSelectField(
        choices=SALES_CHANNEL, null=True, blank=True
    )

While creating a product with postman, my request body is:

{
    "name": "first unit",
    "sku": "first sales chann",
    "sales_channel":["retailer", "wholesaler"]

}

But on serializer.is_valid(), I get this error:

        "sales_channel": [
            "\"['retailer', 'wholesaler']\" is not a valid choice."
        ],

How can I post data on postman for multiselectfield?

Answer 1

You can post sales_channel multiple times in form data like:

sales_channel: retailer sales_cahnnel: wholesaler

N.B: Not in raw data. Ok fine, let me help you. Could you add the below details to your serializer before your meta data ex:

class YourSerializer(serializers.ModelSerializer):
sales_channel = serializers.ListField()
     class Meta:
         model = YourModel

Answer 2

Small Update to the currently accepted answer by @skhynixsk I found it better to use MultipleChoiceField() instead of ListField() since we can pass the correct choices inside MultipleChoiceField() for validation. If we use just ListField(), it will accept anything as the correct choice, instead of validating the required correct choices.

sales_channel = serializers.MultipleChoiceField(["retailer", "wholesaler"])

More on MultipleChoiceField() here

Answer 3

In order to achieve this you need to change your serializer

from rest_framework import fields    

class CustomMultipleChoiceField(fields.MultipleChoiceField):
    def to_representation(self, value):
        return list(super().to_representation(value))

class YourSerializer(serializers.ModelSerializer):
    sales_channel = CustomMultipleChoiceField(choices=SALES_CHANNEL, required=False)

    class Meta:
        model = ProductModel
        fields = '__all__'