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POE::Filter::HTTPD.3pm

NAME

POE::Filter::HTTPD - convert stream to HTTP::Request; HTTP::Response to stream

SYNOPSIS

   $httpd = POE::Filter::HTTPD->new();
   $arrayref_with_http_response_as_string =
     $httpd->put($full_http_response_object);
   $arrayref_with_http_request_object =
     $line->get($arrayref_of_raw_data_chunks_from_driver);
 
 

DESCRIPTION

The HTTPD filter parses the first HTTP 1.0 request from an incoming stream into an HTTP::Request object (if the request is good) or an HTTP::Response object (if the request was malformed). To send a response, give its put() method a HTTP::Response object.

Here is a sample input handler:

   sub got_request {
     my ($heap, $request) = @_[HEAP, ARG0];
 
     # The Filter::HTTPD generated a response instead of a request.
     # There must have been some kind of error.  You could also check
     # (ref($request) eq 'HTTP::Response').
     if ($request->isa('HTTP::Response')) {
       $heap->{wheel}->put($request);
       return;
     }
 
     # Process the request here.
     my $response = HTTP::Response->new(200);
     $response->push_header( 'Content-Type', 'text/html' );
     $response->content( $request->as_string() );
 
     $heap->{wheel}->put($response);
   }
 
 

Please see the documentation for HTTP::Request and HTTP::Response.

PUBLIC FILTER METHODS

Please see POE::Filter.

CAVEATS

It is possible to generate invalid HTTP using libwww. This is specifically a problem if you are talking to a Filter::HTTPD driven daemon using libwww. For example, the following code (taken almost verbatim from the HTTP::Request::Common documentation) will cause an error in a Filter::HTTPD daemon:

   use HTTP::Request::Common;
   use LWP::UserAgent;
 
   my $ua = LWP::UserAgent->new();
   $ua->request(POST 'http://some/poe/driven/site', [ foo => 'bar' ]);
 
 

By default, HTTP::Request is HTTP version agnostic. It makes no attempt to add an HTTP version header unless you specifically declare a protocol using "$request->protocol('HTTP/1.0')".

According to the HTTP 1.0 RFC (1945), when faced with no HTTP version header, the parser is to default to HTTP/0.9. Filter::HTTPD follows this convention. In the transaction detailed above, the Filter::HTTPD based daemon will return a 400 error since POST is not a valid HTTP/0.9 request type.

Streaming Media

It is perfectly possible to use Filter::HTTPD for streaming output media. Even if it's not possible to change the input filter from Filter::HTTPD, by setting the output_filter to Filter::Stream and omitting any content in the HTTP::Response object.

   $wheel->put($response); # Without content, it sends just headers.
   $wheel->set_output_filter(POE::Filter::Stream->new());
   $wheel->put("Raw content.");
 
 

SEE ALSO

POE::Filter.

The SEE ALSO section in POE contains a table of contents covering the entire POE distribution.

BUGS

•

Keep-alive is not supported.

•

The full http 1.0 spec is not supported, specifically DELETE, LINK, and UNLINK.

AUTHORS & COPYRIGHTS

The HTTPD filter was contributed by Artur Bergman.

Please see POE for more information about authors and contributors.