如何将 serializers.RelatedField() 添加到 django rest 框架中的 Meta 类字段

Question

我有一个用于足球比赛的简单 API。我正在使用 Django 2.0 和 Django REST 框架。我有Team 和Player 的这两个模型

class Team(models.Model):
    name = models.CharField(max_length=60)
    budget = models.FloatField(default=100.0) # Millions? 114.53 M

    user = models.OneToOneField(User, unique=True, on_delete=models.CASCADE)
    competitions = models.ManyToManyField(Season)

    def __str__(self):
        return self.name

class Player(models.Model):
    name = models.CharField(max_length=50)
    age = models.IntegerField(null=True)
    inMarket = models.BooleanField(default=False)
    lastInMarket = models.DateTimeField(null=True)

    team = models.ForeignKey(Team, null=True, on_delete=models.DO_NOTHING, related_name='team')

据我所知，这是定义 OneToMany 关系的正确方法，即 Team 有许多 Players。现在，另一方面，我想为具体球队显示APIView，以显示球队的所有信息，包括球员的信息。我有这两个Serializers:

class PlayersSerializer(serializers.ModelSerializer):
    team = serializers.RelatedField(read_only=True)

    class Meta:
        model = Player
        fields = ('id', 'name', 'age', 'position', 'team')

    def create(self, validated_data):
        pass

    def update(self, instance, validated_data):
        pass


class TeamSerializer(serializers.ModelSerializer):
    players = serializers.RelatedField(read_only=True, many=True)

    class Meta:
        model = Team
        fields = ('name', 'user', 'competitions')

    def create(self, validated_data):
        return Team.objects.create(**validated_data)

    def update(self, instance, validated_data):
        instance.players = validated_data
        return instance

这是迄今为止我发现的最好的检索球队球员的方法。但是，我不确定这是否是正确的方法。无论如何，我无法将players 添加到fields，因为Team 模型没有玩家属性（引发异常）。我怎么能以某种方式解决这个问题？我有点迷路了

Answer 1

这真的很容易。您可以使用您在模型中定义的related_name (team)。最好将此字段重命名为players。您可以像以前一样为 Player 定义 Serializer，然后在字段中添加 related_name。在你的情况下team（或players）。然后在 Team serializer 中为玩家添加序列化程序（如果您将他们定义为 related_name，则可以添加玩家）。

在models.py:

class Player(models.Model):
    name = models.CharField(max_length=50)
    age = models.IntegerField(null=True)
    inMarket = models.BooleanField(default=False)
    lastInMarket = models.DateTimeField(null=True)

    team = models.ForeignKey(Team, null=True, on_delete=models.DO_NOTHING, related_name='players')

在serializers.py：

class PlayersSerializer(serializers.ModelSerializer):
    # you don't need RelatedField to Team because players will be under the team
    team = serializers.RelatedField(read_only=True)

    class Meta:
        model = Player
        fields = ('id', 'name', 'age', 'position', 'team')

    def create(self, validated_data):
        pass

    def update(self, instance, validated_data):
        pass

class TeamSerializer(serializers.ModelSerializer):
    players = PlayerSerializer(read_only=True, many=True)

    class Meta:
        model = Team
        fields = ('name', 'user', 'competitions', 'players')

    def create(self, validated_data):
        return Team.objects.create(**validated_data)

    def update(self, instance, validated_data):
        instance.players = validated_data
        return instance

如果您对实施有任何问题，请发送评论并告诉我它是否按预期工作。