maple-json

Serializer sqlachemy object to json

usage

it’s simple to use(take flask-sqlalchemy as an example)

multi instances

posts = Post.query.all()
serializer = Serializer(posts)
data = serializer.data

single instance

post = Post.query.first()
serializer = Serializer(post)
data = serializer.data

exclude some columns

serializer = Serializer(post,exclude=['title'])

only include some column

serializer = Serializer(post,include=['title'])

relation depth

serializer = Serializer(post,depth=3)

• depth default:2

add some custom function

serializer = Serializer(post,extra=['get_post_count'])

Post

class Post(Model):
    ......
    def get_post_count(self):
        return 11

Other

class PostSerializer(Serializer):
    count = Field(source = 'get_post_count',args={'name':'hello'},default=20)
    class Meta:
        include = []
        depth = 2
        include = []
        exclude = []
        extra = ['count']

Just use sqlalchemy like django orm

base query(have finished)

• gt
• lt
• lte
• gte
• contains
• in
• exact
• iexact
• startswith
• istartswith
• iendswith
• endswith
• isnull
• range
• year
• month
• day

Example:

Post.query.filter_by(title__contains = 'sql').all()
Post.query.exclude_by(title__contains = 'sql').all()

relationship query

Post.query.filter_by(tags__name__contains = 'sql').all()

other

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')

Use sqlalchemy better

take flask-sqlalchemy as an example,you can remove part of the repetitive work by use Mixin of ‘models.py’

ModelMixin

Increment ID – id

post = Post(·····)
post.save() 
post.delete()

bulk operation

• bulk_insert
• bulk_update
• bulk_save

ModelTimeMixin

• created_at Data create time
• updated_at Data update time

ModelUserMixin

relate to *User*(many to one)

class Post(ModelUserMixin, Model):

    user_related_name = 'posts'
    titile = ...