第三十五节 取消关注的股票

import re
import pymysql


URL_DICT = dict()

'''
给路由添加正则的原因：在实际开发时，URL中往往会带有很多参数，例如：/add/0000007.html,其中
000007(指股票代码：可以用于数据库提取对应的记录)就是参数，
如果此时没有正则的话，那么就要编写N次@route,添加对应的函数到字典中，此时字典中的键值对有N个，浪费空间，
如果采用正则的话，那么只需要编写一次@route就可以完成多个URL，例如/add/00007.html,add/000036.html对应同一个函数，此时字典中的键值对
会少很多
'''
def route(url):
    def set_func(func):
        URL_DICT[url] = func
        def call_func():
            func()
        return call_func
    return set_func

@route(r'/center.html')
def center_p(set):
    pass

@route(r'/add/(d+).html')
def add_focus(ret):
    # 获取股票代码
    stock_code = ret.group(1)
    # 判断是否有这个股票代码
    conn = pymysql.connect('localhost', 'root', '', 'python_test')
    cursor = conn.cursor()
    sql = "select * from info where code=%s"
    cursor.execute(sql, (stock_code,))
    if not cursor.fetchone():
        cursor.close()
        conn.close()
        return '没有这支股票跑，我们是创业公司，请手下流行'
    else:
        # 判断这个股票代码是否已经关注过
        sql = 'select *from focus where info_id=%s'
        cursor.execute(sql, (stock_code,))
        if cursor.fetchone():
            cursor.close()
            conn.close()
            return '已经关注过了，请勿重复关注'
        else:
            # 添加关注
            sql = 'insert into focus (info_id) select id from info where code=%s'
            cursor.execute(sql, (stock_code,))
            conn.commit()
            cursor.close()
            conn.close()
    return 'add(%s) ok ....' % stock_code

@route(r'/add/(d+).html')
def del_focus(ret):
    # 获取股票代码
    stock_code = ret.group(1)
    # 判断是否有这个股票代码
    conn = pymysql.connect('localhost', 'root', '', 'python_test')
    cursor = conn.cursor()
    sql = "select * from info as i inner join focus as f on i.id=f.info_id where i.code=%s"
    cursor.execute(sql, (stock_code,))
    if not cursor.fetchone():
        cursor.close()
        conn.close()
        return '没有这支股票跑，我们是创业公司，请手下流行'
    else:
        # 判断这个股票代码是否已经关注过
        sql = 'select *from focus where info_id=%s'
        cursor.execute(sql, (stock_code,))
        if not cursor.fetchone():
            cursor.close()
            conn.close()
            return '之前未关注，无法取消'
            # 添加关注
        sql = 'delete into focus (info_id) select id from info where code=%s'
        cursor.execute(sql, (stock_code,))
        conn.commit()
        cursor.close()
        conn.close()
    return 'add(%s) ok ....' % stock_code

@route(r'index.html')
def index_p(ret):
    pass


def application(env, start_response):
    '''env是一个空字典，start_response是web服务器里一个方法的引用，函数return的是body'''
    start_response('200 OK', [('Content-Type', 'text/html;charset=utf-8')])
    file_name = env['PATH INFO']

    try:
        # return URL_DICT[file_name]()
        for url, func in URL_DICT.items():
            '''
            {r"/index.html":index,
            r"/center.html":center,
            r"/add/d+.html":add_focus
            } 
            '''
            ret = re.match(url, file_name)
            if ret:
                return func(ret)
    except Exception as ret:
        return '产生了异常%s' % str(ret)