Python Web programming-concept preheating

The internet is triggering a revolution?? Do not like to see the concept of skipping, note here is just a few excerpts from the Python Core programming book

This is the most exciting part of the Web programming

The "language" used by Web clients and server-side interactions, the standard protocol for Web interaction is HTTP (Hypertext Transfer Protocol). HTTP
Protocol is the upper layer protocol of TCP/IP protocol, which means that the HTTP protocol relies on TCP/IP protocol for low level communication. It's
The responsibility is not to route or deliver the message (the TCP/IP protocol handles these), but rather to process the client by sending, accepting HTTP messages
The request.

The HTTP protocol is a stateless protocol that does not track request information from one client to another, and we
The client/server-side architecture used today is very similar. The server side is running continuously, but the client's activity is based on this structure independent
: Once a client's request is completed, the activity is terminated. New requests can be sent at any time, but they will be processed
into a separate service request. Since each request lacks context, you can notice that some URLs have very long variables and values for
As part of the request in order to provide some status information. Another option is "cookie"--the customer status saved on the client
Information. Later in this chapter, we'll see how to use URLs and cookies to save state information.

Companies with large Web sites will have their entire
The WEB server is placed at the ISP. This physical placement is called "consolidation," which means that your servers and other customers ' services
The ISP is "centrally managed" together with the service. These servers may provide different data for the customer or a part of the
Heavy load (high number of user groups) and designed to store duplicate data systems. A small company's web site may not need this
Large hard drives or network devices, perhaps only one or several "consolidated" servers are located at their ISP.

In either case, most "consolidated" servers are deployed on the backbone of a large ISP, which means they
With a higher "bandwidth", if you want, you can get closer to the core of the Internet, making it faster to connect to the Internet.

This allows the client to bypass many networks for direct and fast access to the server, allowing for a specified period of time to make more guest
Access to services.

One thing to keep in mind is that Web applications are one of the most common forms of network applications, but not unique and not the oldest
Types of forms. The internet appeared earlier than the web nearly 30 years ago. Before the advent of the web, the Internet was used primarily for teaching and research purposes. Because
Most of the systems on the Internet are running on UNIX platforms-a multi-user operating system, many of the initial Internet protocols so far
is still being used.

Note here that the Internet and the Web are not the same, the advent of the Internet before the Web

These protocols include Telnet (which allows the user to log on to the remote host on the Internet, which is still used), and the FTP protocol (text
Transfer Protocol, users can share files and data by uploading and downloading files, so far, Gopher (Web search engine
Form-a small software that crawls on the Internet "gopher" can automatically find the data you are interested in, SMTP or a Simple mail
Protocol (This Protocol is used for the oldest and most widely used e-mail), NNTP (News to News Transfer Protocol).

Since Python's initial emphasis is on Internet programming, you can find all the other things that are mentioned above
On. It is possible to differentiate between "Internet programming" and "Web Programming", which only includes application development for the web, which means
WEB clients and servers are the focus of this chapter.

Internet programming covers a wider range of applications: including some of the Internet protocols we mentioned earlier, such as: FTP, SMTP
Including the network programming and socket programming we mentioned earlier.

Create a Web client using Python (note that both Web clients and server-side applications are web apps)

Python Web programming-concept preheating