Tài liệu Web Client Programming with Perl-Chapter 2: Demystifying the Browser-P1 pdf

... engine. Chapter 2: Demystifying the Browser-P1 Before you start writing your own web programs, you have to become comfortable with the fact that your web browser is just another client. Lots of ... example, the browser is given the following URL: http://hypothetical.ora.com/ The browser interprets the URL as follows: http:// In the first part of the URL,...

Ngày tải lên: 26/01/2014, 07:20

... server response In the server response, the general header and entity headers are the same as those used in the client request. The entity-body is like the one used in the client request, except ... is using. The status code indicates the result of the request, and the reason phrase is a human-readable description of the status-code. The response header t...

Ngày tải lên: 26/01/2014, 07:20

... our source code are the functions that we've bound to the buttons and various actions in the GUI. Remember, this is where the real work comes in; without these functions the GUI would just ... would be nice for the program to remember them, and bring them up automatically the next time we start the program. Here's the final code, with most of the mentioned...

Ngày tải lên: 14/12/2013, 13:15

... protocol, in which the client makes a request, the server responds, and the transaction is then finished. The client initiates the transaction as follows: 1. First, the client contacts the server ... determines that the client used a POST method, processes the URL, executes the program associated with the URL, and pipes the client& apos;s entity-body to...

Ngày tải lên: 26/01/2014, 07:20

... image/jpeg The proxy then examines the URL, contacts www.ora.com, forwards the client& apos;s request, and then returns the response from the server to the original client. When forwarding the request ... on both the inside and outside of the firewall. Computers on the inside of a firewall initiate requests with the proxy, and the proxy then communicates to the...

Ngày tải lên: 26/01/2014, 07:20

... compliant with the HTTP specs, the web server won't understand you! Perhaps your web client works with one web server but not another. Or maybe your web client works most of the time, ... assign the socket to a particular port on the host. The server then uses the listen( ) and accept( ) routines to establish communication on that port. On the other e...

Ngày tải lên: 20/10/2013, 10:15

... example, if the URL used by the client becomes obsolete or is changed, the client may interpret the entity- body incorrectly. Media types for the URL may change, and could be noticed in the HTTP ... not at the location specified by your client. In the event of a redirection, will your client handle it? Does it examine the Location header? The answers to these q...

Ngày tải lên: 20/10/2013, 10:15

... are useful for client programming. The LWP Module The LWP module, in the context of web clients, performs client requests over the network. There are 10 classes in all within the LWP module, ... a client/ server negotiation.  The LWP module is the core of all web client programs. It allows the client to communicate over the network with the server.  T...

Ngày tải lên: 24/10/2013, 08:15

... invoked with no parameters, this returns the default port for the URL defined in the object. The default port is based on the scheme used. Even if the port for the URL is explicitly changed by the ... Since we're programming a web robot, the name of the robot and the email address of the user are mandatory. So, we pass that information to the LWP::RobotU...

Ngày tải lên: 24/10/2013, 08:15

... documents to web browsers without being limited to the functionality of an existing web server. HTTP programming takes you out of the realm of the everyday web user and into the world of the web power ... new page appeared. Clients and Servers Your web browser is an example of a web client. The remote machine containing the document you requested is called a...

Ngày tải lên: 26/01/2014, 07:20