数据库
mysql中建立数据库，并建立账号tester，密码tester。
SHOW DATABASES ;
CREATE DATABASE IF NOT EXISTS `flask-test`;
CREATE USER 'tester'@'localhost' IDENTIFIED BY 'tester';
GRANT ALL PRIVILEGES ON `flask-test`.* TO 'tester'@'localhost';
USE `flask-test`;
配置flask
在flask项目目录下编写三个文件
1 config.py
最主要的是URI。
按照mysql+pymysql://<username>:<password>@<host>/<dbname>[?<options>]编写，配置时要放在引号中。
SQLALCHEMY_ECHO = True会把查询语句打印到console中。
class Config(object):
pass
class ProdConfig(Config):
pass
class DevConfig(Config):
DEBUG = True
SQLALCHEMY_DATABASE_URI = 'mysql+pymysql://tester:tester@localhost:3306/flask-test?charset=utf8'
SQLALCHEMY_ECHO = True
2 main.py
需要安装第三方包：
- sqlalchemy
- pymysql
- flask-script
首先，引入SQLAlchemy包。
然后，用db=SQLAlchemy(app)实例化。
User类中继承db.Model。
-
__tablename__ = 'user_table_name'设置表名。 - id、username和password是字段名。
-
__init__与__repr__可以不用定义。
from flask import Flask
from config import DevConfig
from flask.ext.sqlalchemy import SQLAlchemy
app = Flask(__name__)
app.config.from_object(DevConfig)
db = SQLAlchemy(app)
class User(db.Model):
__tablename__ = 'user_table_name'
id = db.Column(db.Integer(), primary_key=True)
username = db.Column(db.String(255))
password = db.Column(db.String(255))
def __init__(self, username):
self.username = username
def __repr__(self):
return "<User {}>".format(self.username)
3 manager.py
- 从main中引入db与User
-
make_shell_context()函数中，return的dict参数中加入db与User。
from flask.ext.script import Manager, Server
from main import app, db, User
manager = Manager(app)
manager.add_command("server", Server())
@manager.shell
def make_shell_context():
return dict(app=app, db=db, User=User)
if __name__ == "__main__":
manager.run()
shell运行
在terminal中运行
$ python manager.py shell
进入shell环境后输入db.creat_all()得到sqlalchemy转变成sql语句的logging。
>>> db.create_all()
2017-02-05 21:28:36,073 INFO sqlalchemy.engine.base.Engine SHOW VARIABLES LIKE 'sql_mode'
2017-02-05 21:28:36,073 INFO sqlalchemy.engine.base.Engine {}
2017-02-05 21:28:36,075 INFO sqlalchemy.engine.base.Engine SELECT DATABASE()
2017-02-05 21:28:36,075 INFO sqlalchemy.engine.base.Engine {}
2017-02-05 21:28:36,075 INFO sqlalchemy.engine.base.Engine show collation where `Charset` = 'utf8' and `Collation` = 'utf8_bin'
2017-02-05 21:28:36,075 INFO sqlalchemy.engine.base.Engine {}
2017-02-05 21:28:36,077 INFO sqlalchemy.engine.base.Engine SELECT CAST('test plain returns' AS CHAR(60)) AS anon_1
2017-02-05 21:28:36,077 INFO sqlalchemy.engine.base.Engine {}
2017-02-05 21:28:36,083 INFO sqlalchemy.engine.base.Engine SELECT CAST('test unicode returns' AS CHAR(60)) AS anon_1
2017-02-05 21:28:36,083 INFO sqlalchemy.engine.base.Engine {}
2017-02-05 21:28:36,084 INFO sqlalchemy.engine.base.Engine SELECT CAST('test collated returns' AS CHAR CHARACTER SET utf8) COLLATE utf8_bin AS anon_1
2017-02-05 21:28:36,084 INFO sqlalchemy.engine.base.Engine {}
2017-02-05 21:28:36,085 INFO sqlalchemy.engine.base.Engine DESCRIBE `user_table_name`
2017-02-05 21:28:36,085 INFO sqlalchemy.engine.base.Engine {}
2017-02-05 21:28:36,086 INFO sqlalchemy.engine.base.Engine ROLLBACK
2017-02-05 21:28:36,087 INFO sqlalchemy.engine.base.Engine
CREATE TABLE user_table_name (
id INTEGER NOT NULL AUTO_INCREMENT,
username VARCHAR(255),
password VARCHAR(255),
PRIMARY KEY (id)
)
2017-02-05 21:28:36,087 INFO sqlalchemy.engine.base.Engine {}
2017-02-05 21:28:36,104 INFO sqlalchemy.engine.base.Engine COMMIT
查询mysql数据库。
mysql> show tables;
+----------------------+
| Tables_in_flask-test |
+----------------------+
| user_table_name |
+----------------------+
1 row in set (0.00 sec)
mysql> desc user_table_name;
+----------+--------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+----------+--------------+------+-----+---------+----------------+
| id | int(11) | NO | PRI | NULL | auto_increment |
| username | varchar(255) | YES | | NULL | |
| password | varchar(255) | YES | | NULL | |
+----------+--------------+------+-----+---------+----------------+
3 rows in set (0.00 sec)
在flask中创建mysql的表成功。
*: 参照《深入理解Flask》第2章
