Flask是Python3开发平台的小型框架，是DJango框架的轻量版，所谓的轻量，并不是说Flask功能没有DJango强大，而是为了提供用户开发过程中更大的灵活空间，缩减了很多框架性的东西，而不会自动生成框架性的代码。为了开发的灵活性，Flask提供了很多扩展库，如Flask-sqlalchemy，就是对数据库操作的扩展库。
平台开发，咱们经常碰到的就是分页展示功能，几乎每个平台都会使用到，而Flask-sqlalchemy分页采用paginate方法，简单粗暴，直接上代码，以下是获取用户列表的分页代码：
@user_sys.route (“/user/query”,methods =[‘GET’])
def query_users ():
判断当前登陆的用户有效性
if not isCurrentUserValid(current_user):
return getResultAnd2Josn(CODE_CURRENT_USER_INVALID ,MSG_CURRENT_USER_INVALID ,{})
接收并解析请求的json数据
res = request.get_data()
data = json.loads(res)
当前选中的组织机构ID(按需求来,该项目的需求是查看当前组织机构的用户列表)
organization_id = data.get(‘organization_id’)
if organization_id
请求的页码
page_num = data.get(‘page_num’)
每页展示数量
data_count = data.get(‘data_count’)
排序, 1-注册时间降序;2-注册时间升序;3-姓名降序;4-姓名升序
order_by = data.get(‘order_by’)
if page_num >=0 and data_count >0 :
user_order_by = User.createDate.desc()
if 2 == order_by:
user_order_by = User.createDate.asc()
elif 3 == order_by:
为了兼容中文，需要CONVERT
user_order_by = func.CONVERT(literal_column(‘name using gbk’)).desc()
elif 4 == order_by:
user_order_by = func.CONVERT(literal_column(‘name using gbk’)).asc()
搜索字符串
filter = data.get(‘filter’)
if None == filter or len (filter) ==0 :
my_current_user = getCurrentuser()
if my_current_user:
if not is_common_user(my_current_user):
organization = Organization.query.get(my_current_user.organizationId)
sub_organization_ids = organization.get_all_sub_organizations_id()
sub_organization_ids.append(organization_id)
# 重点：分页用户列表,通过BaseQuery类的paginate方法进行分页查询，返回Pagination实例，该该包含了数据列表、数据总量，当前页等信息
user_paginate = User.query.order_by(user_order_by).filter(User.organizationId.in_(sub_organization_ids)).paginate(page =page_num ,per_page =data_count)
返回json给前端
return get_json_users_by_user_paginate(user_paginate)
else :
my_organization_id = my_current_user.organizationId
user_paginate = User.query.order_by(user_order_by).filter(and_(User.organizationId == organization_id ,User.id == my_current_user.id)).paginate(page =page_num ,per_page =data_count)
return get_json_users_by_user_paginate(user_paginate)
else :
return getResultAnd2Josn(CODE_CURRENT_USER_INVALID ,MSG_CURRENT_USER_INVALID ,{})
else :
my_current_user = getCurrentuser()
if my_current_user:
if not is_common_user(my_current_user):
organization = Organization.query.get(my_current_user.organizationId)
sub_organization_ids = organization.get_all_sub_organizations_id()
sub_organization_ids.append(organization_id)
user_paginate = User.query.order_by(user_order_by).filter(and_(User.organizationId.in_(sub_organization_ids),or_(User.name.like(‘%’+filter+”%”),User.account.like(‘%’+ filter +”%”))),and_(User.organizationId == organization_id)).paginate(page =page_num ,per_page =data_count)
return get_json_users_by_user_paginate(user_paginate)
else :
user_paginate = User.query.order_by(user_order_by).filter(
and_(User.organizationId == organization_id ,User.id == my_current_user.id ,
or_(User.name.like(‘%’+ filter +’%’),User.account.like(‘%’+ filter +’%’))),
and_(User.organizationId == organization_id)).paginate(page =page_num ,per_page =data_count)
return get_json_users_by_user_paginate(user_paginate)
else :
return getResultAnd2Josn(CODE_CURRENT_USER_INVALID ,MSG_CURRENT_USER_INVALID ,{})
return getResultAnd2Josn(CODE_FAILED ,MSG_FAILED ,{‘total’:0 ,’items’: []})
Original: https://blog.csdn.net/weishengwen2/article/details/125300851
Author: 板砖也快乐
Title: Python3+flask+sqlalchemy分页查询
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