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Python Django REST Framework Security and Customization Add Custom Field

Tim Wicks
Tim Wicks
12,144 Points
Posted by Tim Wicks
Tim Wicks
12,144 Points

Cannot get correct average following instructions

using instructions I cannot get correct average - it would be great to have an output field so we can debug in this situations.

scorekeeper/serializers.py 
from django.db.models import Avg

from rest_framework import serializers

from . import models


class GameSerializer(serializers.ModelSerializer):
    average_score = serializers.SerializerMethodField()

    def get_average_score(self, data):
        agg = models.Game.scores.all().aggregate(average_score=Avg('score'))    
        return agg['average_score']

    class Meta:
        fields = ('id', 'name', 'average_score')
        model = models.Game




class PlayerSerializer(serializers.ModelSerializer):
    class Meta:
        fields = ('id', 'name', 'age', 'parent_approval')
        model = models.Player

    def validate(self, data):
        if data['age'] < 13 and not data['parent_approval']:
            raise serializers.ValidationError(
                "Children under 13 require parental approval"
            )
        return data


class ScoreSerializer(serializers.ModelSerializer):
    game = serializers.HyperlinkedRelatedField(
        read_only=True, view_name='apiv2:game-detail')
    player = serializers.HyperlinkedRelatedField(
        read_only=True, view_name='apiv2:player-detail')

    class Meta:
        fields = ('id', 'game', 'player', 'score')
        model = models.Score