init

backend/utils/serializers.py

@@ -0,0 +1,118 @@
+"""
+@Remark: 自定义序列化器
+"""
+from rest_framework import serializers
+from rest_framework.fields import empty
+from rest_framework.request import Request
+from rest_framework.serializers import ModelSerializer
+from django.utils.functional import cached_property
+from rest_framework.utils.serializer_helpers import BindingDict
+
+from system.models import User
+
+
+class CustomModelSerializer(ModelSerializer):
+    """
+    增强DRF的ModelSerializer,可自动更新模型的审计字段记录
+    (1)self.request能获取到rest_framework.request.Request对象
+    """
+    # 修改人的审计字段名称, 默认modifier, 继承使用时可自定义覆盖
+    modifier_field_id = 'modifier'
+    modifier_name = serializers.SerializerMethodField(read_only=True)
+
+    def get_modifier_name(self, instance):
+        if not hasattr(instance, 'modifier'):
+            return None
+        queryset = User.objects.filter(id=instance.modifier).values_list('name', flat=True).first()
+        if queryset:
+            return queryset
+        return None
+
+    # 创建人的审计字段名称, 默认creator, 继承使用时可自定义覆盖
+    creator_field_id = 'creator'
+    # 添加默认时间返回格式
+    create_time = serializers.DateTimeField(format="%Y-%m-%d %H:%M:%S", required=False, read_only=True)
+    update_time = serializers.DateTimeField(format="%Y-%m-%d %H:%M:%S", required=False)
+
+    def __init__(self, instance=None, data=empty, request=None, **kwargs):
+        super().__init__(instance, data, **kwargs)
+        self.request: Request = request or self.context.get('request', None)
+
+    def save(self, **kwargs):
+        return super().save(**kwargs)
+
+    def create(self, validated_data):
+        if self.request:
+            if self.modifier_field_id in self.fields.fields:
+                validated_data[self.modifier_field_id] = self.get_request_username()
+            if self.creator_field_id in self.fields.fields:
+                validated_data[self.creator_field_id] = self.get_request_username()
+        return super().create(validated_data)
+
+    def update(self, instance, validated_data):
+        if self.request:
+            if hasattr(self.instance, self.modifier_field_id):
+                self.instance.modifier = self.get_request_username()
+        return super().update(instance, validated_data)
+
+    def get_request_username(self):
+        if getattr(self.request, 'user', None):
+            return getattr(self.request.user, 'username', None)
+        return None
+
+    def get_request_name(self):
+        if getattr(self.request, 'user', None):
+            return getattr(self.request.user, 'name', None)
+        return None
+
+    def get_request_user_id(self):
+        if getattr(self.request, 'user', None):
+            return getattr(self.request.user, 'id', None)
+        return None
+
+    @cached_property
+    def fields(self):
+        fields = BindingDict(self)
+        for key, value in self.get_fields().items():
+            fields[key] = value
+
+        if not hasattr(self, '_context'):
+            return fields
+        is_root = self.root == self
+        parent_is_list_root = self.parent == self.root and getattr(self.parent, 'many', False)
+        if not (is_root or parent_is_list_root):
+            return fields
+
+        try:
+            request = self.request or self.context['request']
+        except KeyError:
+            return fields
+        params = getattr(
+            request, 'query_params', getattr(request, 'GET', None)
+        )
+        if params is None:
+            pass
+        try:
+            filter_fields = params.get('_fields', None).split(',')
+        except AttributeError:
+            filter_fields = None
+
+        try:
+            omit_fields = params.get('_exclude', None).split(',')
+        except AttributeError:
+            omit_fields = []
+
+        existing = set(fields.keys())
+        if filter_fields is None:
+            allowed = existing
+        else:
+            allowed = set(filter(None, filter_fields))
+
+        omitted = set(filter(None, omit_fields))
+        for field in existing:
+            if field not in allowed:
+                fields.pop(field, None)
+            if field in omitted:
+                fields.pop(field, None)
+
+        return fields