Web Client Programming with Perl-Chapter 5: The LWP Library- P1
Web Client Programming with Perl-Chapter 5: The LWP Library- P1
... 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, as ... computes 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...
Tài liệu Web Client Programming with Perl-Chapter 3: Learning HTTP- P1 pdf
... 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...
Web Client Programming with Perl-Chapter 5: The LWP Library- P2
... response code. In the context of web client programming, you'll usually get an HTTP::Response object from LWP: :UserAgent and LWP: :RobotUA. If you plan to write extensions to LWP or a web server ... get the entity-body of the request, call the content( ) method without any parameters, and it will return the object's current entity- body. To define the entity-...
Web Client Programming with Perl-Chapter 4: The Socket Library- P1
... fully 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, but ... to that port, the server accepts the connection and then converses with the client using whatever protocol they agree on (e.g., HTTP, NNTP, SMTP, etc.). Initial...
Web Client Programming with Perl-Chapter 4: The Socket Library- P2
... open_TCP('F', $the_ url[1], $the_ url[2])) { print "Error connecting to web server: $the_ url[1]\n"; exit(-1); } # request the path of the document to get print F "GET $the_ url[3] HTTP/1.0\n"; ... match, the referenced URL is pushed into an array, which is returned at the end of the function. We've saved this in web. pl, and will include it in...
Web Client Programming with Perl-Chapter 6: Example LWP Programs-P1
... > tags in the response.
4. If "Delivered To : " shows up in the reply (with or without text after
the colon), the query was successful but the document is not at the
destination ... $ua->request($request);
They both do the same thing; they request a document from a user-specified
web server and identify themselves in the User-Agent header. But one looks...
Web Client Programming with Perl-Chapter 6: Example LWP Programs-P2
... For the not _web( ), local( ), and remote( )
methods, a similar associative array is returned, where the URL is a key in
the array and denotes that the URL is not HTTP-based, is local to the web ... Example LWP Programs-P2
Then the scan( ) method does all the real work. The scan( ) method accepts a
URL as a parameter. In a nutshell, here's what happens:
The sca...
Tài liệu Web Client Programming with Perl-Chapter 2: Demystifying the Browser-P1 pdf
... 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, you told the browser to use HTTP, the ... In the third line, beginning with the string User-Agent, the client
identifies itself as Mozilla (Netscape) version 3.0, running on
Windows NT.
4. The fourth l...
Tài liệu Web Client Programming with Perl-Chapter 2: Demystifying the Browser-P2 doc
... 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...
Web Client Programming with Perl-Chapter 3: Learning HTTP- P3
... accommodate client- side caching of documents, the client can use the If- Modified-Since header with the GET method. When using this option, the client requests the server to send the requested ... finishes. The close parameter signifies that either the client or server wishes to end the connection (i.e., this is the last transaction). The keep-alive parameter s...
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