DRF一对多序列化AttributeError from missing field

Question

错误：

AttributeError at /stats/matches

Got AttributeError when attempting to get a value for field players on serializer MatchSerializer. The serializer field might be named incorrectly and not match any attribute or key on the Match instance. Original exception text was: 'Match' object has no attribute 'players'.

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型号：

每个Match有10个玩家。在

class Match(models.Model):
    tournament = models.ForeignKey(Tournament, blank=True)
    mid = models.CharField(primary_key=True, max_length=255)
    mlength = models.CharField(max_length=255)
    win_rad = models.BooleanField(default=True)

class Player(models.Model):
    match = models.ForeignKey(Match, on_delete=models.CASCADE)
    playerid = models.CharField(max_length=255, default='novalue')
    # There is also a Meta class that defines unique_together but its omitted for clarity.

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序列化程序：

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Answer 1

这里的问题是，Match模型没有一个名为players的属性，请记住，您正在尝试获取向后关系对象，因此您需要使用djangodocs所说的players_set作为字段。在

你可以用两种方法来解决这个问题 1。向PlayerSerializer添加一个source参数

class MatchSerializer(serializers.ModelSerializer):
    players = PlayerSerializer(many=True, source='player_set')
    class Meta:
        model = Match
        fields = ("mid", "players")

2。更改查找字段

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Answer 2

MatchSerializer在Match的实例中搜索players属性，但找不到，并出现以下错误：

AttributeError at /stats/matches

Got AttributeError when attempting to get a value for field players on 
serializer MatchSerializer. The serializer field might be named 
incorrectly and not match any attribute or key on the Match instance. 
Original exception text was: 'Match' object has no attribute 'players'.

在DRF序列化程序中，一个名为source的参数将显式地告诉您在哪里查找数据。因此，请按如下方式更改MatchSerializer：

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希望有帮助。在