pip3 install flask

#!flask/bin/python
from flask import Flask, jsonify, render_template, Request, Response
from flask import flask_bootstrap
from flask import g
import sqlite3
import time
import datetime

import dbInit

app = Flask(__name__)

def connect_db():
    conn = sqlite3.connect("testDB.db3",check_same_thread = False)
    return conn

conn = connect_db()
cursor = conn.cursor()

#通过在before_request/teardown_request hook方法可以在每次请求连接开始之前和结束时候连接和断开数据库
@app.before_request
def before_request():
    g.db = connect_db()

@app.teardown_request
def teardown_request(exception):
    if hasattr(g, ‘db‘):
        g.db.close()

#但是该方法的缺陷在于没有请求就没法连接数据库，所以如果要在脚本或者python的交互式终端中访问数据库需要这样做
with app.test_request_context():
    app.preprocess_request()
        #now you can use the g.db object
        # dbInit.init_db()

#缺点，不能离开请求上下文依赖，解决方法
def get_connection():
    db = getattr(g, ‘_db‘, None)
    if db is None:
        db = g._db = connect_db()
    return db
#缺点必须使用 db = get_connection() 而不是仅仅直接使用g.db 来访问数据库连接

def initSqliteBD():
    connect_db()
    createUserTable()

def createUserTable():
    cursor.execute(‘create table user (id varchar(20) primary key, name varchar(20))‘)
    conn.commit()

def deleteTable(tableName):
    cursor.execute(‘delete table‘)
    conn.commit()

def insertAnUser(id, name):
    cursor.execute(‘insert into user values(?,?)‘,(id,name))
    conn.commit()

def queryAllUser():
    cursor.execute(‘select id, name from user‘)
    conn.commit()
    return cursor.fetchone()

#===========page route==========
@app.route(‘/‘)
def index():
    return "Hello, World!"

@app.route(‘/index/<name>‘)
def home(name=None):
    return render_template(‘index.html‘,name = name)

@app.route(‘/register‘)
def regiser():
    return render_template(‘register.html‘)

#===========api route==========
@app.route(‘/todo/api/v1.0/user/register‘, methods=[‘GET‘])
def createAnUser():
    insertAnUser(1,‘Jarvis‘)
    return jsonify(‘ok‘)

@app.route(‘/todo/api/v1.0/users‘,methods=[‘GET‘])
def get_users():
    # return jsonify({"users":users})
    return jsonify(queryAllUser())

@app.route(‘/todo/api/v1.0/users/<string:userName>‘,methods=[‘GET‘])
def get_user(userName):
    users = [{"userName":"Jarvis","age":"24"},{"userName":"Mike","age":"23"}]
    user = filter(lambda t: t[userName] == userName, users)
    if len(user) == 0:
        abort(404)
    return jsonify({"task":task[0]})

if __name__ == ‘__main__‘:
    app.run(debug=True)
    initSqliteBD()