sqlitepython-2.7sqlalchemyhttp-postbasehttpserver

Python - BaseHTTPServer , issue with POST and GET


I am making a very simple application with 2 webpages at the moment under URLs: localhost:8080/restaurants/ and localhost:8080/restaurants/new. I have a sqlite database which i manipulate with SQLAlchemy in my python code.

On my first page localhost:8080/restaurants/, this just contains the lists of restaurants available in my database. My second page localhost:8080/restaurants/new, is where i have a form in order to a new restaurant such that it displays on localhost:8080/restaurants. However Whenever i enter a new restaurant name on form at localhost:8080/restaurants/new, it fails to redirect me back to localhost:8080/restaurants/ in order to show me the new restaurant, instead it just remains on the same url link localhost:8080/restaurants/new with the message "No data received" . Below is my code:

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()

for reference here is my database_setup file where i create the database:

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)

I can't figure out why i cannot add new restuarants


Solution

  • I know this was a long time ago, but I figured out your problem. First, the enctype='multipart/form-data' in your do_GET function under the if self.path.endswith("/restaurants/new"): portion is missing a final single quote. Second, you misspelt 'multipart' in if ctype == 'multipart/form-data':. Hope that can help you or others.