GitHub地址: https://github.com/honmaple/maple-json
sqlalchemy object序列化为json
灵感来源于 Django REST framework
多个实例
posts = Post.query.all()
serializer = Seralizer(posts,many=True)
data = serializer.data
单个实例
post = Post.query.first()
serializer = Seralizer(post,many=False)
data = serializer.data
排除字段
serializer = Seralizer(post,exclude=['title'])
仅包括字段
serializer = Seralizer(post,include=['title'])
关系查询深度
serializer = Seralizer(post,depth=3)
-
depth
默认为2
增加一些自定义的函数
serializer = Serializer(post,extra=['get_post_count'])
Post
class Post(Model):
......
def get_post_count(self):
return 11
可传递参数的函数
class PostSerializer(Serializer):
count = Field(source = 'get_post_count',args={'name':'hello'},default=20)
class Meta:
include = []
depth = 2
include = []
exclude = []
extra = ['count']
像django orm一样使用sqlalchemy
djang orm与sqlalchemy相比,为什么很多人都认为django orm更好用,大概就是因为django orm更方便
基本查询(已实现)
gt
lt
lte
gte
contains
in
exact
iexact
startswith
istartswith
iendswith
endswith
isnull
range
year
month
day
示例:
Post.query.filter_by(title__contains = 'sql').all()
Post.query.exclude_by(title__contains = 'sql').all()
关系查询
Post.query.filter_by(tags__name__contains = 'sql').all()
其它
Post.query.filter_by(tags__name__contains = 'sql').or(Post.id == 1,Post.id == 2).all()
Post.query.filter_by(tags__name__contains = 'sql').and(Post.id == 1,Post.id == 2).all()
Post.query.filter_by(tags__name__contains = 'sql').exists()
Post.query.load_only('title')
去掉一些sqlalchemy的重复工作
以flask-sqlalchemy为例,通过继承 models.py 中的Mixin,就可以去除部分重复工作
ModelMixin
自增ID – id
post = Post(·····)
post.save() # 保存
post.delete() # 保存
批量操作
bulk_insert
bulk_update
bulk_save
ModelTimeMixin
增加两字段
-
created_at
数据创建时间 -
updated_at
数据更新时间
ModelUserMixin
关联用户表,与User表现为多对一关系(即一个用户有多个post)
class Post(ModelUserMixin, Model):
user_related_name = 'posts'
titile = ...