"Net::Async::FastCGI::Request" - a single active FastCGI request
use Net::Async::FastCGI;
use IO::Async::Loop;
my $fcgi = Net::Async::FastCGI->new(
on_request => sub {
my ( $fcgi, $req ) = @_;
my $path = $req->param( "PATH_INFO" );
$req->print_stdout( "Status: 200 OK\r\n" .
"Content-type: text/plain\r\n" .
"\r\n" .
"You requested $path" );
$req->finish();
}
);
my $loop = IO::Async::Loop->new();
$loop->add( $fcgi );
$loop->run;
Instances of this object class represent individual requests received from the
webserver that are currently in-progress, and have not yet been completed.
When given to the controlling program, each request will already have its
parameters and STDIN data. The program can then write response data to the
STDOUT stream, messages to the STDERR stream, and eventually finish it.
This module would not be used directly by a program using
"Net::Async::FastCGI", but rather, objects in this class are passed
into the "on_request" event of the containing
"Net::Async::FastCGI" object.
This method returns a reference to a hash containing a copy of the request
parameters that had been sent by the webserver as part of the request.
This method returns the value of a single request parameter, or
"undef" if no such key exists.
Returns the value of the "REQUEST_METHOD" parameter, or
"GET" if there is no value set for it.
Returns the value of the "SCRIPT_NAME" parameter.
Returns the value of the "PATH_INFO" parameter.
Returns the full request path by reconstructing it from "script_name"
and "path_info".
Returns the value of the "QUERY_STRING" parameter.
Returns the value of the "SERVER_PROTOCOL" parameter.
Sets the character encoding used by the request's STDIN, STDOUT and STDERR
streams. This method may be called at any time to change the encoding in
effect, which will be used the next time "read_stdin_line",
"read_stdin", "print_stdout" or "print_stderr"
are called. This encoding will remain in effect until changed again. The
encoding of a new request is determined by the "default_encoding"
parameter of the containing "Net::Async::FastCGI" object. If the
value "undef" is passed, the encoding will be removed, and the above
methods will work directly on bytes instead of encoded strings.
This method works similarly to the "<HANDLE>" operator. If at
least one line of data is available then it is returned, including the
linefeed, and removed from the buffer. If not, then any remaining partial line
is returned and removed from the buffer. If no data is available any more,
then "undef" is returned instead.
This method works similarly to the "read(HANDLE)" function. It returns
the next block of up to $size bytes from the STDIN buffer. If no data is
available any more, then "undef" is returned instead. If $size is
not defined, then it will return all the available data.
This method appends the given data to the STDOUT stream of the FastCGI request,
sending it to the webserver to be sent to the client.
This method appends the given data to the STDERR stream of the FastCGI request,
sending it to the webserver.
This method installs a callback for streaming data to the STDOUT stream.
Whenever the output stream is otherwise-idle, the function will be called to
generate some more data to output. When this function returns
"undef" it indicates the end of the stream, and the request will be
finished with the given exit code.
If this method is used, then care should be taken to ensure that the number of
bytes written to the server matches the number that was claimed in the
"Content-Length", if such was provided. This logic should be
performed by the containing application; "Net::Async::FastCGI" will
not track it.
Returns an IO handle representing the request's STDIN buffer. This may be read
from using the "read" or "readline" functions or the
"<$stdin>" operator.
Note that this will be a tied IO handle, it will not be useable directly as an
OS-level filehandle.
Returns an IO handle representing the request's STDOUT or STDERR streams
respectively. These may written to using "print",
"printf", "say", etc..
Note that these will be tied IO handles, they will not be useable directly as an
OS-level filehandle.
When the request has been dealt with, this method should be called to indicate
to the webserver that it is finished. After calling this method, no more data
may be appended to the STDOUT stream. At some point after calling this method,
the request object will be removed from the containing
"Net::Async::FastCGI" object, once all the buffered outbound data
has been sent.
If present, $exitcode should indicate the numeric status code to send to the
webserver. If absent, a value of 0 is presumed.
Similar to the "stdout" method, except that when the "close"
method is called on the returned filehandle, the request will be finished by
calling "finish".
Returns true if the webserver has already closed the control connection. No
further work on this request is necessary, as it will be discarded.
It is not required to call this method; if the request is aborted then any
output will be discarded. It may however be useful to call just before
expensive operations, in case effort can be avoided if it would otherwise be
wasted.
The following pair of methods form an interface that allows the request to be
used as a source of HTTP::Request objects, responding to them by sending
HTTP::Response objects. This may be useful to fit it in to existing code that
already uses these.
Returns a new "HTTP::Request" object that gives a reasonable
approximation to the request. Because the webserver has translated the
original HTTP request into FastCGI parameters, this may not be a perfect
recreation of the request as received by the webserver.
Sends the given "HTTP::Response" object as the response to this
request. The status, headers and content are all written out to the request's
STDOUT stream and then the request is finished with 0 as the exit code.
To serve contents of files on disk, it may be more efficient to use
"stream_stdout_then_finish":
use Net::Async::FastCGI;
use IO::Async::Loop;
my $fcgi = Net::Async::FastCGI->new(
on_request => sub {
my ( $fcgi, $req ) = @_;
open( my $file, "<", "/path/to/file" );
$req->print_stdout( "Status: 200 OK\r\n" .
"Content-type: application/octet-stream\r\n" .
"\r\n" );
$req->stream_stdout_then_finish(
sub { read( $file, my $buffer, 8192 ) or return undef; return $buffer },
0
);
}
my $loop = IO::Async::Loop->new();
$loop->add( $fcgi );
$loop->run;
It may be more efficient again to instead use the "X-Sendfile" feature
of certain webservers, which allows the webserver itself to serve the file
efficiently. See your webserver's documentation for more detail.
Paul Evans <leonerd@leonerd.org.uk>