Python - BaseHTTPServer ,POST 和 GET 问题

Python - BaseHTTPServer , issue with POST and GET

我正在制作一个非常简单的应用程序,目前在 URL 下有 2 个网页:localhost:8080/restaurants/ 和 localhost:8080/restaurants/new。 我有一个 sqlite 数据库,我在 python 代码中用 SQLAlchemy 操作它。

在我的第一页 localhost:8080/restaurants/ 上,这仅包含我的数据库中可用的餐厅列表。 我的第二页 localhost:8080/restaurants/new 是我有一个新餐厅的表格,它显示在 localhost:8080/restaurants 上。 但是,每当我在 localhost:8080/restaurants/new 的表格中输入新餐厅名称时,它都无法将我重定向回 localhost:8080/restaurants/ 以便向我展示新餐厅,而只是与消息 "No data received" 保持相同的 url link localhost:8080/restaurants/new 。 下面是我的代码:

import cgi
from BaseHTTPServer import BaseHTTPRequestHandler, HTTPServer

#import libraries and modules
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker
from database_setup import Base, Restaurant, MenuItem

#create and connect to database
engine = create_engine('sqlite:///restaurantmenu.db')
Base.metadata.bind=engine
DBSession = sessionmaker(bind=engine)
session = DBSession()


class webServerHandler(BaseHTTPRequestHandler):
    """ class defined in the main method"""

    def do_GET(self):
        try:
            #look for url then ends with '/hello'
            if self.path.endswith("/restaurants"):
                self.send_response(200)

                #indicate reply in form of html to the client
                self.send_header('Content-type', 'text/html')

                #indicates end of https headers in the response
                self.end_headers()

                #obtain all restaurant names from databse
                restaurants = session.query(Restaurant).all()

                output = ""
                output += "<html><body><a href='/restaurants/new'>Add A New Restaurant</a>"
                output += "</br></br>"

                for restaurant in restaurants:
                    output += restaurant.name
                    output += """<div>
                            <a href='#'>Edit</a>
                            <a href='#'>Delete</a>
                            </div>"""
                    output += "</br></br>"
                output += "</body></html>"

                self.wfile.write(output)
                print output
                return


            if self.path.endswith("/restaurants/new"):
                self.send_response(200)
                self.send_header('Content-type', 'text/html')
                self.end_headers()

                output = ""
                output += "<html><body>"
                output += "<h1>Add New Restaurant</h1>"

                output += "<form method='POST' enctype='multipart/form-data action='/restaurants/new'>"
                output += "<input name='newRestaurant' type='text' placeholder='New Restaurant Name'>"
                output += "<input name='Create' type='submit' label='Create'>"
                output += "</form></body></html>"

                self.wfile.write(output)
                return

        except IOError:

            self.send_error(404, "File %s not found" % self.path)



    def do_POST(self):

        try:
            if self.path.endswith("/restaurants/new"):

                ctype, pdict = cgi.parse_header(self.headers.getheader('content-type'))

                #check of content-type is form
                if ctype == 'mulitpart/form-data':

                    #collect all fields from form, fields is a dictionary
                    fields = cgi.parse_multipart(self.rfile, pdict)

                    #extract the name of the restaurant from the form
                    messagecontent = fields.get('newRestaurant')

                    #create the new object
                    newRestaurantName = Restaurant(name = messagecontent[0])
                    session.add(newRestaurantName)
                    session.commit()

                    self.send_response(301)
                    self.send_header('Content-type', 'text/html')
                    self.send_header('Location','/restaurants')
                    self.end_headers()

        except:
            pass




def main():
    """An instance of HTTPServer is created in the main method 
    HTTPServer is built off of a TCP server indicating the 
    transmission protocol
    """
    try:
        port = 8080

        #server address is tuple & contains host and port number
        #host is an empty string in this case
        server = HTTPServer(('', port), webServerHandler)


        print "Web server running on port %s"  % port

        #keep server continually listening until interrupt occurs
        server.serve_forever()


    except KeyboardInterrupt:
        print "^C entered, stopping web server...."

        #shut down server
        server.socket.close()


#run main method
if __name__ == '__main__':
    main()

这里是我创建数据库的 database_setup 文件供参考:

import sys

#importing classes from sqlalchemy module
from sqlalchemy import Column, ForeignKey, Integer, String

#delcaritive_base , used in the configuration
# and class code, used when writing mapper
from sqlalchemy.ext.declarative import declarative_base

#relationship in order to create foreign key relationship
#used when writing the mapper
from sqlalchemy.orm import relationship

#create_engine to used in the configuration code at the
#end of the file
from sqlalchemy import create_engine


#this object will help set up when writing the class code
Base = declarative_base()



class Restaurant(Base):
    """
    class Restaurant corresponds to restaurant table
    in the database to be created.

    table representation for restaurant which
    is in the database 
    """
    __tablename__ = 'restaurant'


    #column definitions for the restaurant table
    id = Column(Integer, primary_key=True)
    name = Column(String(250), nullable=False)



class MenuItem(Base):
    """
    class MenuItem corresponds to restaurant table


    table representation for menu_item which
    is in the database      
    """
    __tablename__ = 'menu_item'

    #column definitions for the restaurant table
    name = Column(String(80), nullable=False)
    id = Column(Integer, primary_key=True)
    course = Column(String(250))
    description = Column(String(250))
    price = Column(String(8))
    restaurant_id = Column(Integer, ForeignKey('restaurant.id'))
    restaurant = relationship(Restaurant)



#create an instance of create_engine class
#and point to the database to be used
engine = create_engine(
    'sqlite:///restaurantmenu.db')


#that will soon be added into the database. makes
#the engine
Base.metadata.create_all(engine)

我不明白为什么我不能添加新的餐厅

我知道这是很久以前的事了,但我发现了你的问题。 首先,do_GET 函数中 if self.path.endswith("/restaurants/new"): 部分下的 enctype='multipart/form-data' 缺少最后一个单引号。其次,您在 if ctype == 'multipart/form-data': 中拼错了 'multipart'。希望对你或其他人有所帮助。

正如 shteeven 所说,问题出在表单中的加密类型上。

由于遗漏了引用,'Content-type' 更改为 'application/x-www-form-urlencoded' 因此在这种情况下,您应该以不同的方式解析它,因为它是一个字符串。

为了管理这两种 enctype,您可以按以下方式修改您的 do_POST

def do_POST(self):

    try:

        if self.path.endswith("/restaurants/new"):

            ctype, pdict = cgi.parse_header(self.headers.getheader('content-type'))

            print ctype

            #check of content-type is form
            if (ctype == 'multipart/form-data') or (ctype == 'application/x-www-form-urlencoded'):

                #collect all fields from form, fields is a dictionary
                if ctype == 'multipart/form-data':
                    fields = cgi.parse_multipart(self.rfile, pdict)
                else:
                    content_length = self.headers.getheaders('Content-length')
                    length = int(content_length[0])
                    body = self.rfile.read(length)
                    fields = urlparse.parse_qs(body)

                #extract the name of the restaurant from the form
                messagecontent = fields.get('newRestaurant')

                #create the new object
                newRestaurantName = Restaurant(name = messagecontent[0])
                session.add(newRestaurantName)
                session.commit()

                self.send_response(301)
                self.send_header('Location','/restaurants')
                self.end_headers()
                return

希望这些额外的信息对您有用!