Ecosyste.ms: Awesome
An open API service indexing awesome lists of open source software.
https://github.com/houxiaozhao/python3-flask-mysql
python3 flask 使用Mysql数据库
https://github.com/houxiaozhao/python3-flask-mysql
flask mysql python python3-flask-mysql restapi
Last synced: 22 days ago
JSON representation
python3 flask 使用Mysql数据库
- Host: GitHub
- URL: https://github.com/houxiaozhao/python3-flask-mysql
- Owner: houxiaozhao
- Created: 2018-08-25T03:55:20.000Z (over 6 years ago)
- Default Branch: master
- Last Pushed: 2023-05-01T21:37:13.000Z (over 1 year ago)
- Last Synced: 2023-05-12T12:28:38.960Z (over 1 year ago)
- Topics: flask, mysql, python, python3-flask-mysql, restapi
- Language: Python
- Homepage:
- Size: 13.7 KB
- Stars: 8
- Watchers: 2
- Forks: 1
- Open Issues: 2
-
Metadata Files:
- Readme: readme.md
Awesome Lists containing this project
README
# 运行
1. ```pip install -r Requirements```
2. 创建mysql数据库 hhh
3. 进入python shell
```python
db.create_all()# 自动根据模型创建数据库表
```
4. ```python app.py```
# python3 flask 使用Mysql数据库
1. 创建flask基本项目结构
```python
from flask import Flask
app = Flask(__name__)
```
2. 安装`flask-sqlalchemy`
```commandline
pip install flask-sqlalchemy
```
3. 导入配置
```python
from flask_sqlalchemy import SQLAlchemy
app.config['SQLALCHEMY_DATABASE_URI'] = 'mysql+pymysql://root:root@localhost/hhh'
app.config['SQLALCHEMY_COMMIT_ON_TEARDOWN'] = True
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = True
db = SQLAlchemy(app)
```
python3 不再支持MySQKdb,连接mysql数据库需要使用pymysql
安装pymysql
`pip install pymysql`
4. 定义表模型
```python
class User(db.Model):
id = db.Column(db.Integer, primary_key=True)
username = db.Column(db.String(64), unique=True, nullable=True)
def __init__(self, username):
self.username = username
def __repr__(self):
return ''.format(self.username)
```
5. 创建表 在python shell中
```commandline
>>> from app import db
>>> db.create_all()
```
6. 添加数据 在python shell中
```commandline
>>> from app import db
>>> from app import User
>>> user=User('hou')
>>> db.session.add(user)
>>> db.session.commit()
```
7. 查询数据库
```bash
>>> User.query.all()
[]
>>> User.query.filter_by(username='hou').first()
```
8. 一对多或一对一表关联
- 定义Post 表模型
```python
from datetime import datetime
class Post(db.Model):
id = db.Column(db.Integer, primary_key=True)
body = db.Column(db.Text)
timestamp = db.Column(db.DateTime, index=True, default=datetime.utcnow)
# 添加外键声明
user_id = db.Column(db.Integer, db.ForeignKey('user.id'))
def __repr__(self):
return ''.format(self.body)
```
- User添加关系
```python
class User(db.Model):
id = db.Column(db.Integer, primary_key=True)
username = db.Column(db.String(64), unique=True, nullable=True)
# 新加的
# 如果您想要一对一关系，您可以把 uselist=False 传给 relationship() 。
posts = db.relationship('Post', backref='user', lazy='dynamic')
def __init__(self, username):
self.username = username
def __repr__(self):
return ''.format(self.username)
```
- 执行创建表
- 添加数据
```bash
>>> from app import *
>>> user=User.query.filter_by(username='hou').first()
>>> post1=Post(body='post1post1post1post1post1post1',user=user)
>>> db.session.add(post1)
>>> db.session.commit()
```
- 查询数据
```bash
>>> user=User.query.filter_by(username='hou').first()
>>> user.posts.all()
[, ]
>>> user.posts.filter_by(id=4).first()
```
9. 多对多表关联
- 定义Category 表模型
```python
class Category(db.Model):
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.String(50))
def __init__(self, name):
self.name = name
def __repr__(self):
return '' % self.name
```
- 定义关联表
```python
categorys = db.Table('categorys',
db.Column('id', db.Integer, primary_key=True),
db.Column('post_id', db.Integer, db.ForeignKey('post.id')),
db.Column('category_id', db.Integer, db.ForeignKey('category.id'))
)
```
- Post 中添加关系
```python
categorys = db.relationship('Category', secondary=categorys, backref=db.backref('posts', lazy='dynamic'))
```
- 执行创建表
- 准备类别数据
```bash
>>> from app import *
>>> category1=Category(name="前端")
>>> category2=Category(name="nodejs")
>>> category3=Category(name="python")
>>> db.session.add(category1)
>>> db.session.add(category2)
>>> db.session.add(category3)
>>> db.session.commit()
```
- 添加post
```bash
>>> from app import *
>>> category1=Category.query.get(1)
>>> category2=Category.query.get(2)
>>> category3=Category.query.get(3)
>>> user=User.query.get(1)
>>> post1=Post(body='关联的post',user=user,categorys=[category1])
>>> post2=Post(body='关联的post',user=user,categorys=[category1,category2,category3])
>>> db.session.add(post1)
>>> db.session.add(post2)
>>> db.session.commit()
```
10. 修改代码结构使其更好的提供接口
11. 提供简单rest接口`user` (有部分改动,以代码为准)
```python
from flask import jsonify, request
from app.api import bp
from app.models import User
from app import db
from app.error import bad_request
@bp.route('/users', methods=['GET'])
def get_users():
limit = min(request.args.get('limit', 10, int), 100)
offset = (request.args.get('page', 1, int) - 1) * request.args.get('limit', 10, int)
return jsonify([user.to_dict() for user in User.query.limit(limit).offset(offset).all()])
@bp.route('/users/', methods=['GET'])
def get_user(id):
return jsonify(User.query.get_or_404(id).to_dict())
@bp.route('/users', methods=['POST'])
def add_user():
data = request.get_json() or {}
if 'username' not in data:
return bad_request('错误的参数')
user = User(username=data['username'])
db.session.add(user)
db.session.commit()
return jsonify(user.to_dict())
@bp.route('/users/', methods=['PUT'])
def update_user(id):
user = User.query.get_or_404(id)
data = request.get_json() or {}
if 'username' not in data:
return bad_request('错误的参数')
setattr(user, 'username', data['username'])
db.session.commit()
return jsonify(user.to_dict())
@bp.route('/users/', methods=['DELETE'])
def delete_user(id):
user = User.query.get_or_404(id)
db.session.delete(user)
db.session.commit()
return jsonify({'message': 'ok'})
```
12. 源代码地址 https://github.com/houxiaozhao/python3-flask-mysql