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Python Django REST Framework Security and Customization Add Custom Field

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