如何在Tornado中的其他类/文件中访问我的数据库级功能？

Question

我是龙卷风的新手,我现在正试图通过这个最近的绊脚石.目前我定义了一些数据库变量,并在初始化Application类时实例化处理程序,设置和数据库连接信息.我还有一个基本处理程序类(名为BaseHandler),它为其他类提供了一个简单的数据库接口.我想将我的一些类拆分为其他文件,并将大部分数据库逻辑放在其他类方法中,并为路由保留application.py,并在需要时实例化这些其他类,并将必要的数据传递给他们为数据库.如何从这些其他文件/类中访问此self.db函数？

application.py:

import tornado.database
import tornado.httpserver
import tornado.ioloop
import tornado.options
import tornado.web

from tornado.options import define, options
from user import User

# Define some startup settings, can be changed through the command line
define("port", default=8888, help="Run on the given HTTP port", type=int)
define("db_host", default="localhost:3306", help="Database host")
define("db_name", default="database_name", help="Database name")
define("db_user", default="user", help="Database username")
define("db_pass", default="password", help="Database password")

class Application(tornado.web.Application):
    def __init__(self):
        handlers = [
            (r"/", MainHandler)
        ]
        settings = dict(
            application_title = u"Test Application",
            template_path = os.path.join(os.path.dirname(__file__), "templates"),
            static_path = os.path.join(os.path.dirname(__file__), "static"),
            autoescape = None
        )
        tornado.web.Application.__init__(self, handlers, **settings)

        self.db = tornado.database.Connection(
            host=options.db_host, database=options.db_name,
            user=options.db_user, password=options.db_pass)

class BaseHandler(tornado.web.RequestHandler):
    @property
    def db(self):
        return self.application.db

class MainHandler(BaseHandler):
    def get(self):
        u = User()
        self.write(tornado.escape.json_encode(u.get_user("test@test.com)))

user.py:

class User(object):
    def get_user(self, email):
        result = self.db.get("SELECT first_name, last_name FROM users WHERE email = %s", email)
        if not result: return False
        return True, result

当我没有将逻辑分离到单独的文件时,这个逻辑确实工作正常,所以我显然做错了什么/遗漏了什么.

Answer 1

我刚才遇到了同样的情况,然后我在github上查看了一些例子并做了.

我将我的文件分开如:

• server.py:运行app
• urls.py:定义handers和ui_modules
• da.py:定义有用的数据访问方法

以下是每个文件的简要介绍,我认为这可以帮助您解决问题.

urls.py

import main
import topic

handlers=[]
handlers.extend(main.handlers)
handlers.extend(topic.handlers)

ui_modules={}

da.py

import tornado.database

from tornado.options import define,options
define("mysql_host", default="127.0.0.1:3306", help="database host")
define("mysql_database", default="forum", help="database name")
define("mysql_user", default="root", help="database user")
define("mysql_password", default="111111", help="database password")

db = tornado.database.Connection(
    host=options.mysql_host, database=options.mysql_database,
    user=options.mysql_user, password=options.mysql_password)

server.py

import os
import tornado.database
import tornado.httpserver
import tornado.ioloop
import tornado.web

from tornado.options import define, options
define("port", default=8888, help="run on the given port", type=int)

import da

class Application(tornado.web.Application):
    def __init__(self):
        from urls import handlers,ui_modules
        settings = dict(
            template_path=os.path.join(os.path.dirname(__file__), "templates"),
            static_path=os.path.join(os.path.dirname(__file__), "static"),
            xsrf_cookies=True,
            cookie_secret="11oETzKXQAGaYdkL5gEmGeJJFuYh7EQnp2XdTP1o/Vo=",
            login_url="/signin",
            ui_modules=ui_modules,
            debug=True,
        )
        super(Application,self).__init__(handlers,**settings)
#       tornado.web.Application.__init__(self, handlers, **settings)
        # Have one global connection to the blog DB across all handlers
        self.db = da.db

def runserver():
    tornado.options.parse_command_line()
    http_server = tornado.httpserver.HTTPServer(Application())
    http_server.listen(options.port)
    tornado.ioloop.IOLoop.instance().start()

if __name__ == "__main__":
    runserver()

你可以使用db'from da import*'然后一切顺利,或者你可以编写一个BaseHandler extends tornado.web.RequestHandler并定义一个属性:

class BaseHandler(tornado.web.RequestHandler):
    @property
    def db(self):
        return self.application.db

扩展BaseHandler的每个处理程序都可以使用self.db来执行数据库操作.