今天整理了一下在django項目中如何使用mongodb, 環境如下:
ubuntu18.04, django2.0.5, drf3.9, mongoengine0.16
第一步:在settings.py中配置mongodb和mysql,配置如下(可以同時使用mysql和mongodb):
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql', # 數據庫引擎
'NAME': 'django_test2', # 你要存儲數據的庫名,事先要創建之
'USER': 'root', # 數據庫用戶名
'PASSWORD': 'wyzane', # 密碼
'HOST': 'localhost', # 主機
'PORT': '3306', # 數據庫使用的端口
},
'mongotest': {
'ENGINE': None,
}
}
import mongoengine
# 連接mongodb中數據庫名稱爲mongotest5的數據庫
conn = mongoengine.connect("mongotest")
第二步:向mongodb中插入數據
1.插入json類型數據
models.py:
import mongoengine
class StudentModel(mongoengine.Document):
name = mongoengine.StringField(max_length=32)
age = mongoengine.IntField()
password = mongoengine.StringField(max_length=32)
views.py:
from rest_framework.views import APIView
class FirstMongoView(APIView):
def post(self, request):
name = request.data["name"]
age = request.data["age"]
password = request.data["password"]
StudentModel.objects.create(name=name, age=age, password=password)
return Response(dict(msg="OK", code=10000))
插入數據格式爲:
{
"name": "nihao",
"age": 18,
"password": "123456"
}
2.插入含有list的json數據
models.py:
import mongoengine
class Student2Model(mongoengine.Document):
name = mongoengine.StringField(max_length=32)
# 用於存儲list類型的數據
score = mongoengine.ListField()
views.py:
from rest_framework.views import APIView
class FirstMongo2View(APIView):
def post(self, request):
name = request.data["name"]
score = request.data["score"]
Student2Model.objects.create(name=name, score=score)
return Response(dict(msg="OK", code=10000))
插入數據格式爲:
{
"name": "test",
"score": [12, 13]
}
3.插入含有dict和list的複雜json數據
models.py:
import mongoengine
class Student3Model(mongoengine.Document):
name = mongoengine.StringField(max_length=32)
# DictField用於存儲字典類型的數據
score = mongoengine.DictField()
views.py:
from rest_framework.views import APIView
class FirstMongo3View(APIView):
def post(self, request):
name = request.data["name"]
score = request.data["score"]
Student3Model.objects.create(name=name, score=score)
return Response(dict(msg="OK", code=10000))
插入數據格式爲:
{
"name": "test",
"score": {"xiaoming": 12, "xiaoli": 13}
}
或者:
{
"name": "test",
"score": {"xiaoming": 12, "xiaoli": {"xiaozhao": 14}}
}
或者:
{
"name": "test",
"score": {"xiaoming": 12, "xiaoli": {"xiaozhao": {"xiaoliu": 12, "xiaojian": 18}}}
}
或者:
{
"name": "test",
"score": {"xiaoming": 12, "xiaoli": {"xiaozhao": {"xiaoliu": 12, "xiaojian": [12,13,14]}}}
}
第三步:查詢mongodb中的數據
1.查詢並序列化複雜json數據
serializers.py:
class StudentSerializer(serializers.Serializer):
name = serializers.CharField()
score = serializers.DictField() # 序列化複雜的json數據
# DictField與EmbeddedDocumentField類似,但是比EmbeddedDocumentField更靈活
views.py:
class FirstMongo4View(APIView):
def get(self, request):
student_info = Student3Model.objects.all()
# 增加過濾條件
# student_info = Student3Model.objects.filter(name="test1")
ser = StudentSerializer(instance=student_info, many=True)
return Response(dict(msg="OK", code="10000", data=ser.data))
2.序列化mongodb中含有嵌套關係的兩個document
models.py:
class AuthorModel(mongoengine.EmbeddedDocument):
author_name = mongoengine.StringField(max_length=32)
age = mongoengine.IntField()
class BookModel(mongoengine.Document):
book_name = mongoengine.StringField(max_length=64)
publish = mongoengine.DateTimeField(default=datetime.datetime.utcnow())
words = mongoengine.IntField()
author = mongoengine.EmbeddedDocumentField(AuthorModel)
serializers.py: 序列化時注意與rest_framework的序列化中DictField()的區別
from rest_framework_mongoengine import serializers as s1
class AuthorSerializer(s1.DocumentSerializer):
# DocumentSerializer繼承自drf中的ModelSerializer,用於代替ModelSerializer序列化mongodb中的document.
# 具體可以到官網上查看
class Meta:
model = AuthorModel
fields = ('author_name', 'age')
class BookSerializer(s1.DocumentSerializer):
author = AuthorSerializer()
class Meta:
model = BookModel
fields = ('book_name', 'publish', 'words', 'author')
AuthorSerializer還可以這樣寫:
class AuthorSerializer(s1.EmbeddedDocumentSerializer):
# EmbeddedDocumentSerializer繼承了DocumentSerializer
class Meta:
model = AuthorModel
fields = ('author_name', 'age')
views.py:
class BookView(APIView):
def get(self, request):
"""
查詢數據
:param request:
:return:
"""
books = BookModel.objects.all()
ser = BookSerializer(instance=books, many=True)
return Response(dict(msg="OK", code="10000", data=ser.data))
序列化mongodb中相關聯的兩個表時,如果序列化器繼承自rest_framework中的Serializer和ModelSerializer,會拋出如下異常:
Django serialization to JSON error: 'MetaDict' object has no attribute 'concrete_model'
此時,序列化器需要繼承自rest_framework_mongoengine的類,具體可以查看官網:
http://umutbozkurt.github.io/...
今天就聊到這裏,如有問題,歡迎交流。