HTTP::Server::Simple(3)                    User Contributed Perl Documentation


NAME
       HTTP::Server::Simple - Lightweight HTTP server

SYNOPSIS
        use warnings;
        use strict;

        use HTTP::Server::Simple;

        my $server = HTTP::Server::Simple->new();
        $server->run();

       However, normally you will sub-class the HTTP::Server::Simple::CGI
       module (see HTTP::Server::Simple::CGI);

        package Your::Web::Server;
        use base qw(HTTP::Server::Simple::CGI);

        sub handle_request {
            my ($self, $cgi) = @_;

            #... do something, print output to default
            # selected filehandle...

        }

        1;

DESCRIPTION
       This is a simple standalone HTTP server. By default, it doesn't thread
       or fork. It does, however, act as a simple frontend which can be used
       to build a standalone web-based application or turn a CGI into one.

       It is possible to use Net::Server classes to create forking, pre-
       forking, and other types of more complicated servers; see "net_server".

       By default, the server traps a few signals:

       HUP When you "kill -HUP" the server, it lets the current request finish
           being processed, then uses the "restart" method to re-exec itself.
           Please note that in order to provide restart-on-SIGHUP,
           HTTP::Server::Simple sets a SIGHUP handler during initialisation.
           If your request handling code forks you need to make sure you reset
           this or unexpected things will happen if somebody sends a HUP to
           all running processes spawned by your app (e.g. by "kill -HUP
           <script>")

       PIPE
           If the server detects a broken pipe while writing output to the
           client, it ignores the signal. Otherwise, a client closing the
           connection early could kill the server.

EXAMPLE
        #!/usr/bin/perl
        {
        package MyWebServer;

        use HTTP::Server::Simple::CGI;
        use base qw(HTTP::Server::Simple::CGI);

        my %dispatch = (
            '/hello' => \&resp_hello,
            # ...
        );

        sub handle_request {
            my $self = shift;
            my $cgi  = shift;

            my $path = $cgi->path_info();
            my $handler = $dispatch{$path};

            if (ref($handler) eq "CODE") {
                print "HTTP/1.0 200 OK\r\n";
                $handler->($cgi);

            } else {
                print "HTTP/1.0 404 Not found\r\n";
                print $cgi->header,
                      $cgi->start_html('Not found'),
                      $cgi->h1('Not found'),
                      $cgi->end_html;
            }
        }

        sub resp_hello {
            my $cgi  = shift;   # CGI.pm object
            return if !ref $cgi;

            my $who = $cgi->param('name');

            print $cgi->header,
                  $cgi->start_html("Hello"),
                  $cgi->h1("Hello $who!"),
                  $cgi->end_html;
        }

        }

        # start the server on port 8080
        my $pid = MyWebServer->new(8080)->background();
        print "Use 'kill $pid' to stop server.\n";

METHODS
   HTTP::Server::Simple->new($port, $family)
       API call to start a new server.  Does not actually start listening
       until you call "->run()".  If omitted, $port defaults to 8080, and
       $family defaults to Socket::AF_INET.  The alternative domain is
       Socket::AF_INET6.

   lookup_localhost
       Looks up the local host's IP address, and returns it.  For most hosts,
       this is 127.0.0.1, or possibly "::1".

   port [NUMBER]
       Takes an optional port number for this server to listen on.

       Returns this server's port. (Defaults to 8080)

   family [NUMBER]
       Takes an optional address family for this server to use.  Valid values
       are Socket::AF_INET and Socket::AF_INET6.  All other values are
       silently changed into Socket::AF_INET for backwards compatibility with
       previous versions of the module.

       Returns the address family of the present listening socket.  (Defaults
       to Socket::AF_INET.)

   host [address]
       Takes an optional host address for this server to bind to.

       Returns this server's bound address (if any).  Defaults to "undef"
       (bind to all interfaces).

   background [ARGUMENTS]
       Runs the server in the background, and returns the process ID of the
       started process.  Any arguments will be passed through to "run".

   run [ARGUMENTS]
       Run the server.  If all goes well, this won't ever return, but it will
       start listening for "HTTP" requests.  Any arguments passed to this will
       be passed on to the underlying Net::Server implementation, if one is
       used (see "net_server").

   net_server
       User-overridable method. If you set it to a Net::Server subclass, that
       subclass is used for the "run" method.  Otherwise, a minimal
       implementation is used as default.

   restart
       Restarts the server. Usually called by a HUP signal, not directly.

   stdio_handle [FILEHANDLE]
       When called with an argument, sets the socket to the server to that
       arg.

       Returns the socket to the server; you should only use this for actual
       socket-related calls like "getsockname".  If all you want is to read or
       write to the socket, you should use "stdin_handle" and "stdout_handle"
       to get the in and out filehandles explicitly.

   stdin_handle
       Returns a filehandle used for input from the client.  By default,
       returns whatever was set with "stdio_handle", but a subclass could do
       something interesting here.

   stdout_handle
       Returns a filehandle used for output to the client.  By default,
       returns whatever was set with "stdio_handle", but a subclass could do
       something interesting here.

IMPORTANT SUB-CLASS METHODS
       A selection of these methods should be provided by sub-classes of this
       module.

   handler
       This method is called after setup, with no parameters.  It should print
       a valid, full HTTP response to the default selected filehandle.

   setup(name => $value, ...)
       This method is called with a name => value list of various things to do
       with the request.  This list is given below.

       The default setup handler simply tries to call methods with the names
       of keys of this list.

         ITEM/METHOD   Set to                Example
         -----------  ------------------    ------------------------
         method       Request Method        "GET", "POST", "HEAD"
         protocol     HTTP version          "HTTP/1.1"
         request_uri  Complete Request URI  "/foobar/baz?foo=bar"
         path         Path part of URI      "/foobar/baz"
         query_string Query String          undef, "foo=bar"
         port         Received Port         80, 8080
         peername     Remote name           "200.2.4.5", "foo.com"
         peeraddr     Remote address        "200.2.4.5", "::1"
         peerport     Remote port           42424
         localname    Local interface       "localhost", "myhost.com"

   headers([Header => $value, ...])
       Receives HTTP headers and does something useful with them.  This is
       called by the default setup() method.

       You have lots of options when it comes to how you receive headers.

       You can, if you really want, define parse_headers() and parse them raw
       yourself.

       Secondly, you can intercept them very slightly cooked via the setup()
       method, above.

       Thirdly, you can leave the setup() header as-is (or calling the
       superclass setup() for unknown request items).  Then you can define
       headers() in your sub-class and receive them all at once.

       Finally, you can define handlers to receive individual HTTP headers.
       This can be useful for very simple SOAP servers (to name a crack-fueled
       standard that defines its own special HTTP headers).

       To do so, you'll want to define the header() method in your subclass.
       That method will be handed a (key,value) pair of the header name and
       the value.

   accept_hook
       If defined by a sub-class, this method is called directly after an
       accept happens.  An accept_hook to add SSL support might look like
       this:

           sub accept_hook {
               my $self = shift;
               my $fh   = $self->stdio_handle;

               $self->SUPER::accept_hook(@_);

               my $newfh =
               IO::Socket::SSL->start_SSL( $fh,
                   SSL_server    => 1,
                   SSL_use_cert  => 1,
                   SSL_cert_file => 'myserver.crt',
                   SSL_key_file  => 'myserver.key',
               )
               or warn "problem setting up SSL socket: " . IO::Socket::SSL::errstr();

               $self->stdio_handle($newfh) if $newfh;
           }

   post_setup_hook
       If defined by a sub-class, this method is called after all setup has
       finished, before the handler method.

   print_banner
       This routine prints a banner before the server request-handling loop
       starts.

       Methods below this point are probably not terribly useful to define
       yourself in subclasses.

   parse_request
       Parse the HTTP request line.  Returns three values, the request method,
       request URI and the protocol.

   parse_headers
       Parses incoming HTTP headers from STDIN, and returns an arrayref of
       "(header => value)" pairs.  See "headers" for possibilities on how to
       inspect headers.

   setup_listener
       This routine binds the server to a port and interface.

   after_setup_listener
       This method is called immediately after setup_listener. It's here just
       for you to override.

   bad_request
       This method should print a valid HTTP response that says that the
       request was invalid.

   valid_http_method($method)
       Given a candidate HTTP method in $method, determine if it is valid.
       Override if, for example, you'd like to do some WebDAV.  The default
       implementation only accepts "GET", "POST", "HEAD", "PUT", "PATCH",
       "DELETE" and "OPTIONS".

AUTHOR
       Best Practical Solutions, LLC <modules@bestpractical.com>

CONTRIBUTORS
       Jesse Vincent, <jesse@bestpractical.com>. Original author.

       Marcus Ramberg <drave@thefeed.no> contributed tests, cleanup, etc

       Sam Vilain, <samv@cpan.org> contributed the CGI.pm split-out and
       header/setup API.

       Example section by almut on perlmonks, suggested by Mark Fuller.

BUGS
       There certainly are some. Please report them via rt.cpan.org

LICENSE
       This software is Copyright (c) 2004-2015 Best Practical Solutions

       This library is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself.

perl v5.38.0                      2023-07-25           HTTP::Server::Simple(3)