phpman > perldoc > Net::Server::HTTP(3pm)

NAME
    Net::Server::HTTP - very basic Net::Server based HTTP server class

TEST ONE LINER
        perl -e 'use base qw(Net::Server::HTTP); main->run(port => 8080)'
        # will start up an echo server

SYNOPSIS
        use base qw(Net::Server::HTTP);
        __PACKAGE__->run;

        sub process_http_request {
            my $self = shift;

            print "Content-type: text/html\n\n";
            print "<form method=post action=/bam><input type=text name=foo><input type=submit></form>\n";

            require Data::Dumper;
            local $Data::Dumper::Sortkeys = 1;

            require CGI;
            my $form = {};
            my $q = CGI->new; $form->{$_} = $q->param($_) for $q->param;

            print "<pre>".Data::Dumper->Dump([\%ENV, $form], ['*ENV', 'form'])."</pre>";
        }

DESCRIPTION
    Even though Net::Server::HTTP doesn't fall into the normal parallel of the other Net::Server
    flavors, handling HTTP requests is an often requested feature and is a standard and simple
    protocol.

    Net::Server::HTTP begins with base type MultiType defaulting to Net::Server::Fork. It is easy to
    change it to any of the other Net::Server flavors by passing server_type => $other_flavor in the
    server configuration. The port has also been defaulted to port 80 - but could easily be changed
    to another through the server configuration. You can also very easily add ssl by including,
    proto=>"ssl" and provide a SSL_cert_file and SSL_key_file.

    For example, here is a basic server that will bind to all interfaces, will speak both HTTP on
    port 8080 as well as HTTPS on 8443, and will speak both IPv4, as well as IPv6 if it is
    available.

        use base qw(Net::Server::HTTP);

        __PACKAGE__->run(
            port  => [8080, "8443/ssl"],
            ipv   => '*', # IPv6 if available
            SSL_key_file  => '/my/key',
            SSL_cert_file => '/my/cert',
        );

METHODS
    "_init_access_log"
        Used to open and initialize any requested access_log (see access_log_file and
        access_log_format).

    "_tie_client_stdout"
        Used to initialize automatic response header parsing.

    "process_http_request"
        Will be passed the client handle, and will have STDOUT and STDIN tied to the client.

        During this method, the %ENV will have been set to a standard CGI style environment. You
        will need to be sure to print the Content-type header. This is one change from the other
        standard Net::Server base classes.

        During this method you can read from %ENV and STDIN just like a normal HTTP request in other
        web servers. You can print to STDOUT and Net::Server will handle the header negotiation for
        you.

        Note: Net::Server::HTTP has no concept of document root or script aliases or default
        handling of static content. That is up to the consumer of Net::Server::HTTP to work out.

        Net::Server::HTTP comes with a basic %ENV display installed as the default
        process_http_request method.

    "process_request"
        This method has been overridden in Net::Server::HTTP - you should not use it while using
        Net::Server::HTTP. This overridden method parses the environment and sets up request alarms
        and handles dying failures. It calls process_http_request once the request is ready and
        headers have been parsed.

    "process_headers"
        Used to read in the incoming headers and set the ENV.

    "_init_http_request_info"
        Called at the end of process_headers. Initializes the contents of http_request_info.

    "http_request_info"
        Returns a hashref of information specific to the current request. This information will be
        used for logging later on.

    "send_status"
        Takes an HTTP status and a message. Sends out the correct headers.

    "send_500"
        Calls send_status with 500 and the argument passed to send_500.

    c<log_http_request>
        Called at the end of post_process_request. The default method looks for the default
        access_log_format and checks if logging was initialized during _init_access_log. If both of
        these exist, the http_request_info is formatted using http_log_format and the result is
        logged.

    "http_log_format"
        Takes a format string, and request_info and returns a formatted string. The format should
        follow the apache mod_log_config specification. As in the mod_log_config specification,
        backslashes, quotes should be escaped with backslashes and you may also include \n and \t
        characters as well.

        The following is a listing of the available parameters as well as sample output based on a
        very basic HTTP server.

            %%                %                 # a percent
            %a                ::1               # remote ip
            %A                ::1               # local ip
            %b                83                # response size (- if 0) Common Log Format
            %B                83                # response size
            %{bar}C           baz               # value of cookie by that name
            %D                916               # elapsed in microseconds
            %{HTTP_COOKIE}e   bar=baz           # value of %ENV by that name
            %f                -                 # filename - unused
            %h                ::1               # remote host if lookups are on, remote ip otherwise
            %H                http              # request protocol
            %{Host}i          localhost:8080    # request header by that name
            %I                336               # bytes received including headers
            %l                -                 # remote logname - unsused
            %m                GET               # request method
            %n                Just a note       # http_note by that name
            %{Content-type}o  text/html         # output header by that name
            %O                189               # response size including headers
            %p                8080              # server port
            %P                22999             # pid - does not support %{tid}P
            q                 ?hello=there      # query_string including ? (- otherwise)
            r                 GET /bam?hello=there HTTP/1.1      # the first line of the request
            %s                200               # response status
            %u                -                 # remote user - unused
            %U                /bam              # request path (no query string)
            %t                [06/Jun/2012:12:14:21 -0600]       # http_log_time standard format
            %t{%F %T %z}t     [2012-06-06 12:14:21 -0600]        # http_log_time with format
            %T                0                 # elapsed time in seconds
            %v                localhost:8080    # http_log_vhost - partial implementation
            %V                localhost:8080    # http_log_vhost - partial implementation
            %X                -                 # Connection completed and is 'close' (-)

        Additionally, the log parsing allows for the following formats.

            %>s               200               # status of last request
            %<s               200               # status of original request
            %400a             -                 # remote ip if status is 400
            %!400a            ::1               # remote ip if status is not 400
            %!200a            -                 # remote ip if status is not 200

        There are few bits not completely implemented:

            > and <    # There is no internal redirection
            %I         # The answer to this is based on header size and Content-length
                         instead of the more correct actual number of bytes read though
                         in common cases those would be the same.
            %X         # There is no Connection keepalive in the default server.
            %v and %V  # There are no virtual hosts in the default HTTP server.
            %{tid}P    # The default servers are not threaded.

        See the "access_log_format" option for how to set a different format as well as to see the
        default string.

    "exec_cgi"
        Allow for calling an external script as a CGI. This will use IPC::Open3 to fork a new
        process and read/write from it.

            use base qw(Net::Server::HTTP);
            __PACKAGE__->run;

            sub process_http_request {
                my $self = shift;

                if ($ENV{'PATH_INFO'} && $ENV{'PATH_INFO'} =~ s{^ (/foo) (?= $ | /) }{}x) {
                   $ENV{'SCRIPT_NAME'} = $1;
                   my $file = "/var/www/cgi-bin/foo"; # assuming this exists
                   return $self->exec_cgi($file);
                }

                print "Content-type: text/html\n\n";
                print "<a href=/foo>Foo</a>";
            }

        At this first release, the parent server is not tracking the child script which may cause
        issues if the script is running when a HUP is received.

    "http_log_time"
        Used to implement the %t format.

    "http_log_env"
        Used to implement the %e format.

    "http_log_cookie"
        Used to implement the %C format.

    "http_log_header_in"
        used to implement the %i format.

    "http_log_note"
        Used to implement the %n format.

    "http_note"
        Takes a key and an optional value. If passed a key and value, sets the note for that key.
        Always returns the value. These notes currently only are used for %{key}n output format.

    "http_log_header_out"
        Used to implement the %o format.

    "http_log_pid"
        Used to implement the %P format.

    "http_log_vhost"
        Used to implement the %v and %V formats.

    "http_log_constat"
        Used to implement the %X format.

    "exec_trusted_perl"
        Allow for calling an external perl script. This method will still fork, but instead of using
        IPC::Open3, it simply requires the perl script. That means that the running script will be
        able to make use of any shared memory. It also means that the STDIN/STDOUT/STDERR handles
        the script is using are those directly bound by the server process.

            use base qw(Net::Server::HTTP);
            __PACKAGE__->run;

            sub process_http_request {
                my $self = shift;

                if ($ENV{'PATH_INFO'} && $ENV{'PATH_INFO'} =~ s{^ (/foo) (?= $ | /) }{}x) {
                   $ENV{'SCRIPT_NAME'} = $1;
                   my $file = "/var/www/cgi-bin/foo"; # assuming this exists
                   return $self->exec_trusted_perl($file);
                }

                print "Content-type: text/html\n\n";
                print "<a href=/foo>Foo</a>";
            }

        At this first release, the parent server is not tracking the child script which may cause
        issues if the script is running when a HUP is received.

    "exec_fork_hook"
        This method is called after the fork of exec_trusted_perl and exec_cgi hooks. It is passed
        the pid (0 if the child) and the file being ran. Note, that the hook will not be called from
        the child during exec_cgi.

    "http_dispatch"
        Called if the default process_http_request and process_request methods have not been
        overridden and "app" configuration parameters have been passed. In this case this replaces
        the default echo server. You can also enable this subsystem for your own direct use by
        setting enable_dispatch to true during configuration. See the "app" configuration item. It
        will be passed a dispatch qr (regular expression) generated during _check_dispatch, and a
        dispatch table. The qr will be applied to path_info. This mechanism could be used to augment
        Net::Server::HTTP with document root and virtual host capabilities.

OPTIONS
    In addition to the command line arguments of the Net::Server base classes you can also set the
    following options.

    max_header_size
        Defaults to 100_000. Maximum number of bytes to read while parsing headers.

    server_revision
        Defaults to Net::Server::HTTP/$Net::Server::VERSION.

    timeout_header
        Defaults to 15 - number of seconds to wait for parsing headers.

    timeout_idle
        Defaults to 60 - number of seconds a request can be idle before the request is closed.

    access_log_file
        Defaults to undef. If true, this represents the location of where the access log should be
        written to. If a special value of STDERR is passed, the access log entry will be writing to
        the same location as the ERROR log.

    access_log_format
        Should be a valid apache log format that will be passed to http_log_format. See the
        http_log_format method for more information.

        The default value is the NCSA extended/combined log format:

            '%h %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-Agent}i\"'

    app Takes one or more items and registers them for dispatch. Arguments may be supplied as an
        arrayref containing a location/target pairs, a hashref containing a location/target pairs, a
        bare code ref that will use "/" as the location and the codref as the target, a string with
        a space indicating "location target", a string containing "location=target", or finally a
        string that will be used as both location and target. For items passed as an arrayref or
        hashref, the target may be a coderef which will be called and should handle the request. In
        all other cases the target should be a valid executable suitable for passing to exec_cgi.

        The locations will be added in the order that they are configured. They will be added to a
        regular expression which will be applied to the incoming PATH_INFO string. If the match is
        successful, the $ENV{'SCRIPT_NAME'} will be set to the matched portion and the matched
        portion will be removed from $ENV{'PATH_INFO'}.

        Once an app has been passed, it is necessary for the server to listen on /. Therefore if "/"
        has not been specifically configured for dispatch, the first found dispatch target will also
        be used to handle "/".

        For convenience, if the log_level is 2 or greater, the dispatch table is output to the log.

        This mechanism is left as a generic mechanism suitable for overriding by servers meant to
        handle more complex dispatch. At the moment there is no handling of virtual hosts. At some
        point we will add in the default ability to play static content and likely for the ability
        to configure virtual hosts - or that may have to wait for a third party module.

            app => "/home/paul/foo.cgi",
              # Dispatch: /home/paul/foo.cgi => home/paul/foo.cgi
              # Dispatch: / => home/paul/foo.cgi (default)


            app => "../../foo.cgi",
            app => "./bar.cgi",
            app => "baz ./bar.cgi",
            app => "bim=./bar.cgi",
              # Dispatch: /foo.cgi => ../../foo.cgi
              # Dispatch: /bar.cgi => ./bar.cgi
              # Dispatch: /baz => ./bar.cgi
              # Dispatch: /bim => ./bar.cgi
              # Dispatch: / => ../../foo.cgi (default)


            app => "../../foo.cgi",
            app => "/=./bar.cgi",
              # Dispatch: /foo.cgi => ../../foo.cgi
              # Dispatch: / => ./bar.cgi

            # you could also do this on the commandline
            net-server HTTP app ../../foo.cgi app /=./bar.cgi

            # extended options when configured from code

            Net::Server::HTTP->run(app => { # loses order of matching
              '/' => sub { ... },
              '/foo' => sub { ... },
              '/bar' => '/path/to/some.cgi',
            });

            Net::Server::HTTP->run(app => [
              '/' => sub { ... },
              '/foo' => sub { ... },
              '/bar' => '/path/to/some.cgi',
            ]);

TODO
    Add support for writing out HTTP/1.1.

AUTHOR
    Paul T. Seamons paul AT seamons.com

THANKS
    See Net::Server

SEE ALSO
    Please see also Net::Server::Fork, Net::Server::INET, Net::Server::PreFork,
    Net::Server::PreForkSimple, Net::Server::MultiType, Net::Server::Single Net::Server::SIG
    Net::Server::Daemonize Net::Server::Proto