Django Serializer Method Field

Question

Can't seem to find the right google search for this so here it goes:

I have a field in my serializer:

likescount = serializers.IntegerField(source='post.count', read_only=True) 

which counts all the related field "post".

Now I want to use that field as part of my method:

def popularity(self, obj):         like = self.likescount             time = datetime.datetime.now()             return like/time 

Is this possible?

Answer 1

assuming post.count is being used to measure the number of likes on a post and you don't actually intend to divide an integer by a timestamp in your popularity method, then try this:

use a SerializerMethodField

likescount = serializers.SerializerMethodField('get_popularity')  def popularity(self, obj):     likes = obj.post.count     time = #hours since created     return likes / time if time > 0 else likes 

however I would recommend making this a property in your model

in your model:

@property def popularity(self):     likes = self.post.count     time = #hours since created     return likes / time if time > 0 else likes 

then use a generic Field to reference it in your serializer:

class ListingSerializer(serializers.ModelSerializer):     ...     popularity = serializers.Field(source='popularity')