1HTTP::Daemon(3) User Contributed Perl Documentation HTTP::Daemon(3)
2
6 HTTP::Daemon - a simple http server class
7
9 use HTTP::Daemon;
10 use HTTP::Status;
11 my $d = HTTP::Daemon->new || die;
13 print "Please contact me at: <URL:", $d->url, ">\n";
14 while (my $c = $d->accept) {
15 while (my $r = $c->get_request) {
16 if ($r->method eq 'GET' and $r->uri->path eq "/xyzzy") {
17 # remember, this is *not* recommended practice :-)
18 $c->send_file_response("/etc/passwd");
19 }
20 else {
21 $c->send_error(RC_FORBIDDEN)
22 }
23 }
24 $c->close;
25 undef($c);
26 }
27
29 Instances of the "HTTP::Daemon" class are HTTP/1.1 servers that listen
30 on a socket for incoming requests. The "HTTP::Daemon" is a subclass of
31 "IO::Socket::IP", so you can perform socket operations directly on it
32 too.
33 The accept() method will return when a connection from a client is
35 available. The returned value will be an "HTTP::Daemon::ClientConn"
36 object which is another "IO::Socket::IP" subclass. Calling the
37 get_request() method on this object will read data from the client and
38 return an "HTTP::Request" object. The ClientConn object also provide
39 methods to send back various responses.
40 This HTTP daemon does not fork(2) for you. Your application, i.e. the
42 user of the "HTTP::Daemon" is responsible for forking if that is
43 desirable. Also note that the user is responsible for generating
44 responses that conform to the HTTP/1.1 protocol.
45 The following methods of "HTTP::Daemon" are new (or enhanced) relative
47 to the "IO::Socket::IP" base class:
48 $d = HTTP::Daemon->new
50 $d = HTTP::Daemon->new( %opts )
51 The constructor method takes the same arguments as the
52 "IO::Socket::IP" constructor, but unlike its base class it can also
53 be called without any arguments. The daemon will then set up a
54 listen queue of 5 connections and allocate some random port number.
55 A server that wants to bind to some specific address on the
57 standard HTTP port will be constructed like this:
58 $d = HTTP::Daemon->new(
60 LocalAddr => 'www.thisplace.com',
61 LocalPort => 80,
62 );
63 See IO::Socket::IP for a description of other arguments that can be
65 used configure the daemon during construction.
66 $c = $d->accept
68 $c = $d->accept( $pkg )
69 ($c, $peer_addr) = $d->accept
70 This method works the same the one provided by the base class, but
71 it returns an "HTTP::Daemon::ClientConn" reference by default. If
72 a package name is provided as argument, then the returned object
73 will be blessed into the given class. It is probably a good idea
74 to make that class a subclass of "HTTP::Daemon::ClientConn".
75 The accept method will return "undef" if timeouts have been enabled
77 and no connection is made within the given time. The timeout()
78 method is described in IO::Socket::IP.
79 In list context both the client object and the peer address will be
81 returned; see the description of the accept method IO::Socket for
82 details.
83 $d->url
85 Returns a URL string that can be used to access the server root.
86 $d->product_tokens
88 Returns the name that this server will use to identify itself.
89 This is the string that is sent with the "Server" response header.
90 The main reason to have this method is that subclasses can override
91 it if they want to use another product name.
92 The default is the string "libwww-perl-daemon/#.##" where "#.##" is
94 replaced with the version number of this module.
95 The "HTTP::Daemon::ClientConn" is a "IO::Socket::IP" subclass.
97 Instances of this class are returned by the accept() method of
98 "HTTP::Daemon". The following methods are provided:
99 $c->get_request
101 $c->get_request( $headers_only )
102 This method reads data from the client and turns it into an
103 "HTTP::Request" object which is returned. It returns "undef" if
104 reading fails. If it fails, then the "HTTP::Daemon::ClientConn"
105 object ($c) should be discarded, and you should not try call this
106 method again on it. The $c->reason method might give you some
107 information about why $c->get_request failed.
108 The get_request() method will normally not return until the whole
110 request has been received from the client. This might not be what
111 you want if the request is an upload of a large file (and with
112 chunked transfer encoding HTTP can even support infinite request
113 messages - uploading live audio for instance). If you pass a TRUE
114 value as the $headers_only argument, then get_request() will return
115 immediately after parsing the request headers and you are
116 responsible for reading the rest of the request content. If you
117 are going to call $c->get_request again on the same connection you
118 better read the correct number of bytes.
119 $c->read_buffer
121 $c->read_buffer( $new_value )
122 Bytes read by $c->get_request, but not used are placed in the read
123 buffer. The next time $c->get_request is called it will consume
124 the bytes in this buffer before reading more data from the network
125 connection itself. The read buffer is invalid after
126 $c->get_request has failed.
127 If you handle the reading of the request content yourself you need
129 to empty this buffer before you read more and you need to place
130 unconsumed bytes here. You also need this buffer if you implement
131 services like 101 Switching Protocols.
132 This method always returns the old buffer content and can
134 optionally replace the buffer content if you pass it an argument.
135 $c->reason
137 When $c->get_request returns "undef" you can obtain a short string
138 describing why it happened by calling $c->reason.
139 $c->proto_ge( $proto )
141 Return TRUE if the client announced a protocol with version number
142 greater or equal to the given argument. The $proto argument can be
143 a string like "HTTP/1.1" or just "1.1".
144 $c->antique_client
146 Return TRUE if the client speaks the HTTP/0.9 protocol. No status
147 code and no headers should be returned to such a client. This
148 should be the same as !$c->proto_ge("HTTP/1.0").
149 $c->head_request
151 Return TRUE if the last request was a "HEAD" request. No content
152 body must be generated for these requests.
153 $c->force_last_request
155 Make sure that $c->get_request will not try to read more requests
156 off this connection. If you generate a response that is not self
157 delimiting, then you should signal this fact by calling this
158 method.
159 This attribute is turned on automatically if the client announces
161 protocol HTTP/1.0 or worse and does not include a "Connection:
162 Keep-Alive" header. It is also turned on automatically when
163 HTTP/1.1 or better clients send the "Connection: close" request
164 header.
165 $c->send_status_line
167 $c->send_status_line( $code )
168 $c->send_status_line( $code, $mess )
169 $c->send_status_line( $code, $mess, $proto )
170 Send the status line back to the client. If $code is omitted 200
171 is assumed. If $mess is omitted, then a message corresponding to
172 $code is inserted. If $proto is missing the content of the
173 $HTTP::Daemon::PROTO variable is used.
174 $c->send_crlf
176 Send the CRLF sequence to the client.
177 $c->send_basic_header
179 $c->send_basic_header( $code )
180 $c->send_basic_header( $code, $mess )
181 $c->send_basic_header( $code, $mess, $proto )
182 Send the status line and the "Date:" and "Server:" headers back to
183 the client. This header is assumed to be continued and does not
184 end with an empty CRLF line.
185 See the description of send_status_line() for the description of
187 the accepted arguments.
188 $c->send_header( $field, $value )
190 $c->send_header( $field1, $value1, $field2, $value2, ... )
191 Send one or more header lines.
192 $c->send_response( $res )
194 Write a "HTTP::Response" object to the client as a response. We
195 try hard to make sure that the response is self delimiting so that
196 the connection can stay persistent for further request/response
197 exchanges.
198 The content attribute of the "HTTP::Response" object can be a
200 normal string or a subroutine reference. If it is a subroutine,
201 then whatever this callback routine returns is written back to the
202 client as the response content. The routine will be called until
203 it return an undefined or empty value. If the client is HTTP/1.1
204 aware then we will use chunked transfer encoding for the response.
205 $c->send_redirect( $loc )
207 $c->send_redirect( $loc, $code )
208 $c->send_redirect( $loc, $code, $entity_body )
209 Send a redirect response back to the client. The location ($loc)
210 can be an absolute or relative URL. The $code must be one the
211 redirect status codes, and defaults to "301 Moved Permanently"
212 $c->send_error
214 $c->send_error( $code )
215 $c->send_error( $code, $error_message )
216 Send an error response back to the client. If the $code is missing
217 a "Bad Request" error is reported. The $error_message is a string
218 that is incorporated in the body of the HTML entity body.
219 $c->send_file_response( $filename )
221 Send back a response with the specified $filename as content. If
222 the file is a directory we try to generate an HTML index of it.
223 $c->send_file( $filename )
225 $c->send_file( $fd )
226 Copy the file to the client. The file can be a string (which will
227 be interpreted as a filename) or a reference to an "IO::Handle" or
228 glob.
229 $c->daemon
231 Return a reference to the corresponding "HTTP::Daemon" object.
232
234 RFC 2616
235 IO::Socket::IP, IO::Socket
237
239 Copyright 1996-2003, Gisle Aas
240 This library is free software; you can redistribute it and/or modify it
242 under the same terms as Perl itself.
243perl v5.28.1 2019-02-02 HTTP::Daemon(3)