我正在尝试创建一个 api，用户可以在其中创建程序并向其添加规则。规则必须按优先顺序执行。我正在使用 Django rest 框架来实现这一点，并且我试图在不使用 ModelSerializer 的情况下使用 Serializer 来实现这一点。使用序列化器提供您的解决方案。序列化器类
一个程序可以有很多规则，一个规则可以在多个程序中。所以，我正在使用 many_to_many 关系，我还希望用户更改程序中规则的顺序，为了实现这一点，我使用了一个名为 Priority 的直通表，我在其中使用优先级字段跟踪规则和程序之间的关系
模型.py
class Program(models.Model):
name = models.CharField(max_length=32)
description = models.TextField(blank=True)
rules = models.ManyToManyField(Rule, through='Priority')
class Rule(models.Model):
name = models.CharField(max_length=20)
description = models.TextField(blank=True)
rule = models.CharField(max_length=256)
class Priority(models.Model):
program = models.ForeignKey(Program, on_delete=models.CASCADE)
rule = models.ForeignKey(Rule, on_delete=models.CASCADE)
priority = models.PositiveIntegerField()
def save(self, *args, **kwargs):
super(Priority, self).save(*args, **kwargs)
序列化器.py
class RuleSerializer(serializers.Serializer):
name = serializers.CharField(max_length=20)
description = serializers.CharField(allow_blank=True)
rule = serializers.CharField(max_length=256)
def create(self, validated_data):
return Rule.objects.create(**validated_data)
def update(self, instance, validated_data):
instance.name = validated_data.get('name', instance.name)
instance.description = validated_data.get('description', instance.description)
instance.rule = validated_data.get('rule', instance.rule)
instance.save()
return instance
class PrioritySerializer(serializers.Serializer):
rule_id = serializers.IntegerField(source='rule.id')
rule_name = serializers.CharField(source='rule.name')
rule_rule = serializers.CharField(source='rule.rule')
priority = serializers.IntegerField()
class ProgramSerializer(serializers.Serializer):
id = serializers.IntegerField()
name = serializers.CharField(max_length=32)
description = serializers.CharField(style={'base_template': 'textarea.html'})
rules = PrioritySerializer(source='priority_set', many=True)
def create(self, validated_data):
rules_data = validated_data.pop('rules')
program_obj = Program.objects.create(**validated_data)
priority = 0
for rule in rules_data:
rule_obj = Rule.objects.get(pk=rule.rule_id)
priority += 1
Priority.objects.create(program=program_obj, rule=rule_obj, priority=priority)
return program_obj
views.py
class ProgramList(APIView):
"""
List all programs, or create a new program.
"""
def get(self, request, format=None):
programs = Program.objects.all()
serializers = ProgramSerializer(programs, many=True)
return Response(serializers.data)
def post(self, request, format=None):
serializer = ProgramSerializer(data=request.data, partial=True)
print(serializer.initial_data)
if serializer.is_valid():
serializer.save()
return Response(serializer.data, status=status.HTTP_201_CREATED)
return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
当我向 http://localhost:8000/api/programs/ 发出获取请求时，我得到了这个响应
[
{
"id": 1,
"name": "some",
"description": "hahah",
"rules": [
{
"rule_id": 3,
"rule_name": "DAIEA",
"rule_rule": "date,and,invoice,equal,amount",
"priority": 1
},
{
"rule_id": 2,
"rule_name": "DAIEA",
"rule_rule": "date,and,invoice,equal,amount",
"priority": 2
},
{
"rule_id": 1,
"rule_name": "DAI=A",
"rule_rule": "date,and,invoice,equal,amount",
"priority": 3
}
]
},
{
"id": 2,
"name": "DAI=AS",
"description": "Date and Invoice equal Amount Sumif",
"rules": []
},
]
我在规则字段下获得了规则列表，但是当我使用此 request.data 发出发布请求以在 rule.id 的帮助下创建一个包含规则的新程序时，
发布数据:
{
"name": "DAI=AS",
"description": "Date and Invoice equal Amount Sumif",
"rules": [
{
"rule_id": 1
},
{
"rule_id": 2
}
]
}
在序列化过程之后，validated_data 包含 priority_set 字段而不是 rules 字段，如下所示
{
'name': 'DAI=AS',
'description': 'Date and Invoice equal Amount Sumif',
'priority_set': [
OrderedDict([('rule', {'id': 1})]),
OrderedDict([('rule', {'id': 2})])
]
}
我不希望序列化程序将规则更改为 priority_set
此外，我在 priority_set 中获取 OrderedDict 列表，而不是我需要规则对象字典
这就是我在序列化过程之后想要的，
{
"name": "DAI=AS",
"description": "Date and Invoice equal Amount Sumif",
"rules": [
{
"rule_id": 1
},
{
"rule_id": 2
}
]
}
提前致谢
最佳答案
解决方案一:
验证数据中的字段使用源属性重命名。您可以在序列化程序的 create 方法中使用重命名的属性。
对于嵌套的序列化程序，验证数据似乎包含 OrderedDict。你可以把它转换成普通的Dict，并且可以得到规则id。
class ProgramSerializer(serializers.Serializer):
id = serializers.IntegerField()
name = serializers.CharField(max_length=32)
description = serializers.CharField(style={'base_template': 'textarea.html'})
rules = PrioritySerializer(source='priority_set', many=True)
def create(self, validated_data):
rules_data = validated_data.pop('priority_set')
program_obj = Program.objects.create(**validated_data)
priority = 0
for rule in rules_data:
rule_obj = Rule.objects.get(pk=dict(rule)["rule"]["id"])
priority += 1
Priority.objects.create(program=program_obj, rule=rule_obj, priority=priority)
return program_obj
解决方案 2:
您可以将源名称为 priority_set 的 rules 设置为 read_only 并可以从请求数据中提取它。
class ProgramSerializer(serializers.Serializer):
id = serializers.IntegerField()
name = serializers.CharField(max_length=32)
description = serializers.CharField(style={'base_template': 'textarea.html'})
rules = PrioritySerializer(source='priority_set', many=True, read_only=True)
def create(self, validated_data):
rules_data = self.context["request"].data["rules"]
program_obj = Program.objects.create(**validated_data)
priority = 0
for rule in rules_data:
rule_obj = Rule.objects.get(pk=rule["rule_id"])
priority += 1
Priority.objects.create(program=program_obj, rule=rule_obj, priority=priority)
return program_obj
您需要将请求上下文传递给序列化器
serializer = ProgramSerializer(data=request.data, partial=True, context={"request": request})
解决方案 3:
在Priority模型的program外键中添加related_name
program = models.ForeignKey(Program, related_name="rule", on_delete=models.CASCADE)
将 ProgramSerializer 中的 rules 字段重命名为其他名称，例如规则，并删除源。
class ProgramSerializer(serializers.Serializer):
id = serializers.IntegerField()
name = serializers.CharField(max_length=32)
description = serializers.CharField(style={'base_template': 'textarea.html'})
rule = PrioritySerializer(many=True)
def create(self, validated_data):
rules_data = validated_data.pop('rule')
program_obj = Program.objects.create(**validated_data)
priority = 0
for rule in rules_data:
rule_obj = Rule.objects.get(pk=dict(rule)["rule"]["id"])
priority += 1
Priority.objects.create(program=program_obj, rule=rule_obj, priority=priority)
return program_obj
现在您将能够使用 rule 键发布和检索数据。您可以根据需要重命名它。
关于python - Serializers.validated_data 字段已更改为 DRF 中的源值，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/69297409/