ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/AnyEvent-HTTP/HTTP.pm
Revision: 1.140
Committed: Wed Mar 6 19:29:18 2024 UTC (8 weeks, 2 days ago) by root
Branch: MAIN
CVS Tags: HEAD
Changes since 1.139: +5 -1 lines
Log Message:
*** empty log message ***

File Contents

# Content
1 =head1 NAME
2
3 AnyEvent::HTTP - simple but non-blocking HTTP/HTTPS client
4
5 =head1 SYNOPSIS
6
7 use AnyEvent::HTTP;
8
9 http_get "http://www.nethype.de/", sub {
10 my ($body, $hdr) = @_;
11 print "$hdr->{URL} Status: $hdr->{Status}\n";
12 print $body;
13 };
14
15 # ... do something else here
16
17 =head1 DESCRIPTION
18
19 This module is an L<AnyEvent> user, you need to make sure that you use and
20 run a supported event loop.
21
22 This module implements a simple, stateless and non-blocking HTTP
23 client. It supports GET, POST and other request methods, cookies and more,
24 all on a very low level. It can follow redirects, supports proxies, and
25 automatically limits the number of connections to the values specified in
26 the RFC.
27
28 It should generally be a "good client" that is enough for most HTTP
29 tasks. Simple tasks should be simple, but complex tasks should still be
30 possible as the user retains control over request and response headers.
31
32 The caller is responsible for authentication management, cookies (if
33 the simplistic implementation in this module doesn't suffice), referer
34 and other high-level protocol details for which this module offers only
35 limited support.
36
37 =head2 METHODS
38
39 =over 4
40
41 =cut
42
43 package AnyEvent::HTTP;
44
45 use common::sense;
46
47 use Errno ();
48
49 use AnyEvent 5.0 ();
50 use AnyEvent::Util ();
51 use AnyEvent::Handle ();
52
53 use base Exporter::;
54
55 our $VERSION = 2.25;
56
57 our @EXPORT = qw(http_get http_post http_head http_request);
58
59 our $USERAGENT = "Mozilla/5.0 (compatible; U; AnyEvent-HTTP/$VERSION; +http://software.schmorp.de/pkg/AnyEvent)";
60 our $MAX_RECURSE = 10;
61 our $PERSISTENT_TIMEOUT = 3;
62 our $TIMEOUT = 300;
63 our $MAX_PER_HOST = 4; # changing this is evil
64
65 our $PROXY;
66 our $ACTIVE = 0;
67
68 my %KA_CACHE; # indexed by uhost currently, points to [$handle...] array
69 my %CO_SLOT; # number of open connections, and wait queue, per host
70
71 =item http_get $url, key => value..., $cb->($data, $headers)
72
73 Executes an HTTP-GET request. See the http_request function for details on
74 additional parameters and the return value.
75
76 =item http_head $url, key => value..., $cb->($data, $headers)
77
78 Executes an HTTP-HEAD request. See the http_request function for details
79 on additional parameters and the return value.
80
81 =item http_post $url, $body, key => value..., $cb->($data, $headers)
82
83 Executes an HTTP-POST request with a request body of C<$body>. See the
84 http_request function for details on additional parameters and the return
85 value.
86
87 =item http_request $method => $url, key => value..., $cb->($data, $headers)
88
89 Executes a HTTP request of type C<$method> (e.g. C<GET>, C<POST>). The URL
90 must be an absolute http or https URL.
91
92 When called in void context, nothing is returned. In other contexts,
93 C<http_request> returns a "cancellation guard" - you have to keep the
94 object at least alive until the callback get called. If the object gets
95 destroyed before the callback is called, the request will be cancelled.
96
97 The callback will be called with the response body data as first argument
98 (or C<undef> if an error occurred), and a hash-ref with response headers
99 (and trailers) as second argument.
100
101 All the headers in that hash are lowercased. In addition to the response
102 headers, the "pseudo-headers" (uppercase to avoid clashing with possible
103 response headers) C<HTTPVersion>, C<Status> and C<Reason> contain the
104 three parts of the HTTP Status-Line of the same name. If an error occurs
105 during the body phase of a request, then the original C<Status> and
106 C<Reason> values from the header are available as C<OrigStatus> and
107 C<OrigReason>.
108
109 The pseudo-header C<URL> contains the actual URL (which can differ from
110 the requested URL when following redirects - for example, you might get
111 an error that your URL scheme is not supported even though your URL is a
112 valid http URL because it redirected to an ftp URL, in which case you can
113 look at the URL pseudo header).
114
115 The pseudo-header C<Redirect> only exists when the request was a result
116 of an internal redirect. In that case it is an array reference with
117 the C<($data, $headers)> from the redirect response. Note that this
118 response could in turn be the result of a redirect itself, and C<<
119 $headers->{Redirect}[1]{Redirect} >> will then contain the original
120 response, and so on.
121
122 If the server sends a header multiple times, then their contents will be
123 joined together with a comma (C<,>), as per the HTTP spec.
124
125 If an internal error occurs, such as not being able to resolve a hostname,
126 then C<$data> will be C<undef>, C<< $headers->{Status} >> will be
127 C<590>-C<599> and the C<Reason> pseudo-header will contain an error
128 message. Currently the following status codes are used:
129
130 =over 4
131
132 =item 595 - errors during connection establishment, proxy handshake.
133
134 =item 596 - errors during TLS negotiation, request sending and header processing.
135
136 =item 597 - errors during body receiving or processing.
137
138 =item 598 - user aborted request via C<on_header> or C<on_body>.
139
140 =item 599 - other, usually nonretryable, errors (garbled URL etc.).
141
142 =back
143
144 A typical callback might look like this:
145
146 sub {
147 my ($body, $hdr) = @_;
148
149 if ($hdr->{Status} =~ /^2/) {
150 ... everything should be ok
151 } else {
152 print "error, $hdr->{Status} $hdr->{Reason}\n";
153 }
154 }
155
156 Additional parameters are key-value pairs, and are fully optional. They
157 include:
158
159 =over 4
160
161 =item recurse => $count (default: $MAX_RECURSE)
162
163 Whether to recurse requests or not, e.g. on redirects, authentication and
164 other retries and so on, and how often to do so.
165
166 Only redirects to http and https URLs are supported. While most common
167 redirection forms are handled entirely within this module, some require
168 the use of the optional L<URI> module. If it is required but missing, then
169 the request will fail with an error.
170
171 =item headers => hashref
172
173 The request headers to use. Currently, C<http_request> may provide its own
174 C<Host:>, C<Content-Length:>, C<Connection:> and C<Cookie:> headers and
175 will provide defaults at least for C<TE:>, C<Referer:> and C<User-Agent:>
176 (this can be suppressed by using C<undef> for these headers in which case
177 they won't be sent at all).
178
179 You really should provide your own C<User-Agent:> header value that is
180 appropriate for your program - I wouldn't be surprised if the default
181 AnyEvent string gets blocked by webservers sooner or later.
182
183 Also, make sure that your headers names and values do not contain any
184 embedded newlines.
185
186 =item timeout => $seconds
187
188 The time-out to use for various stages - each connect attempt will reset
189 the timeout, as will read or write activity, i.e. this is not an overall
190 timeout.
191
192 Default timeout is 5 minutes.
193
194 =item proxy => [$host, $port[, $scheme]] or undef
195
196 Use the given http proxy for all requests, or no proxy if C<undef> is
197 used.
198
199 C<$scheme> must be either missing or must be C<http> for HTTP.
200
201 If not specified, then the default proxy is used (see
202 C<AnyEvent::HTTP::set_proxy>).
203
204 Currently, if your proxy requires authorization, you have to specify an
205 appropriate "Proxy-Authorization" header in every request.
206
207 Note that this module will prefer an existing persistent connection,
208 even if that connection was made using another proxy. If you need to
209 ensure that a new connection is made in this case, you can either force
210 C<persistent> to false or e.g. use the proxy address in your C<sessionid>.
211
212 =item body => $string
213
214 The request body, usually empty. Will be sent as-is (future versions of
215 this module might offer more options).
216
217 =item cookie_jar => $hash_ref
218
219 Passing this parameter enables (simplified) cookie-processing, loosely
220 based on the original netscape specification.
221
222 The C<$hash_ref> must be an (initially empty) hash reference which
223 will get updated automatically. It is possible to save the cookie jar
224 to persistent storage with something like JSON or Storable - see the
225 C<AnyEvent::HTTP::cookie_jar_expire> function if you wish to remove
226 expired or session-only cookies, and also for documentation on the format
227 of the cookie jar.
228
229 Note that this cookie implementation is not meant to be complete. If
230 you want complete cookie management you have to do that on your
231 own. C<cookie_jar> is meant as a quick fix to get most cookie-using sites
232 working. Cookies are a privacy disaster, do not use them unless required
233 to.
234
235 When cookie processing is enabled, the C<Cookie:> and C<Set-Cookie:>
236 headers will be set and handled by this module, otherwise they will be
237 left untouched.
238
239 =item tls_ctx => $scheme | $tls_ctx
240
241 Specifies the AnyEvent::TLS context to be used for https connections. This
242 parameter follows the same rules as the C<tls_ctx> parameter to
243 L<AnyEvent::Handle>, but additionally, the two strings C<low> or
244 C<high> can be specified, which give you a predefined low-security (no
245 verification, highest compatibility) and high-security (CA and common-name
246 verification) TLS context.
247
248 The default for this option is C<low>, which could be interpreted as "give
249 me the page, no matter what".
250
251 See also the C<sessionid> parameter.
252
253 =item sessionid => $string
254
255 The module might reuse connections to the same host internally (regardless
256 of other settings, such as C<tcp_connect> or C<proxy>). Sometimes (e.g.
257 when using TLS or a specfic proxy), you do not want to reuse connections
258 from other sessions. This can be achieved by setting this parameter to
259 some unique ID (such as the address of an object storing your state data
260 or the TLS context, or the proxy IP) - only connections using the same
261 unique ID will be reused.
262
263 =item on_prepare => $callback->($fh)
264
265 In rare cases you need to "tune" the socket before it is used to
266 connect (for example, to bind it on a given IP address). This parameter
267 overrides the prepare callback passed to C<AnyEvent::Socket::tcp_connect>
268 and behaves exactly the same way (e.g. it has to provide a
269 timeout). See the description for the C<$prepare_cb> argument of
270 C<AnyEvent::Socket::tcp_connect> for details.
271
272 =item tcp_connect => $callback->($host, $service, $connect_cb, $prepare_cb)
273
274 In even rarer cases you want total control over how AnyEvent::HTTP
275 establishes connections. Normally it uses L<AnyEvent::Socket::tcp_connect>
276 to do this, but you can provide your own C<tcp_connect> function -
277 obviously, it has to follow the same calling conventions, except that it
278 may always return a connection guard object.
279
280 The connections made by this hook will be treated as equivalent to
281 connections made the built-in way, specifically, they will be put into
282 and taken from the persistent connection cache. If your C<$tcp_connect>
283 function is incompatible with this kind of re-use, consider switching off
284 C<persistent> connections and/or providing a C<sessionid> identifier.
285
286 There are probably lots of weird uses for this function, starting from
287 tracing the hosts C<http_request> actually tries to connect, to (inexact
288 but fast) host => IP address caching or even socks protocol support.
289
290 =item on_header => $callback->($headers)
291
292 When specified, this callback will be called with the header hash as soon
293 as headers have been successfully received from the remote server (not on
294 locally-generated errors).
295
296 It has to return either true (in which case AnyEvent::HTTP will continue),
297 or false, in which case AnyEvent::HTTP will cancel the download (and call
298 the finish callback with an error code of C<598>).
299
300 This callback is useful, among other things, to quickly reject unwanted
301 content, which, if it is supposed to be rare, can be faster than first
302 doing a C<HEAD> request.
303
304 The downside is that cancelling the request makes it impossible to re-use
305 the connection. Also, the C<on_header> callback will not receive any
306 trailer (headers sent after the response body).
307
308 Example: cancel the request unless the content-type is "text/html".
309
310 on_header => sub {
311 $_[0]{"content-type"} =~ /^text\/html\s*(?:;|$)/
312 },
313
314 =item on_body => $callback->($partial_body, $headers)
315
316 When specified, all body data will be passed to this callback instead of
317 to the completion callback. The completion callback will get the empty
318 string instead of the body data.
319
320 It has to return either true (in which case AnyEvent::HTTP will continue),
321 or false, in which case AnyEvent::HTTP will cancel the download (and call
322 the completion callback with an error code of C<598>).
323
324 The downside to cancelling the request is that it makes it impossible to
325 re-use the connection.
326
327 This callback is useful when the data is too large to be held in memory
328 (so the callback writes it to a file) or when only some information should
329 be extracted, or when the body should be processed incrementally.
330
331 It is usually preferred over doing your own body handling via
332 C<want_body_handle>, but in case of streaming APIs, where HTTP is
333 only used to create a connection, C<want_body_handle> is the better
334 alternative, as it allows you to install your own event handler, reducing
335 resource usage.
336
337 =item want_body_handle => $enable
338
339 When enabled (default is disabled), the behaviour of AnyEvent::HTTP
340 changes considerably: after parsing the headers, and instead of
341 downloading the body (if any), the completion callback will be
342 called. Instead of the C<$body> argument containing the body data, the
343 callback will receive the L<AnyEvent::Handle> object associated with the
344 connection. In error cases, C<undef> will be passed. When there is no body
345 (e.g. status C<304>), the empty string will be passed.
346
347 The handle object might or might not be in TLS mode, might be connected
348 to a proxy, be a persistent connection, use chunked transfer encoding
349 etc., and configured in unspecified ways. The user is responsible for this
350 handle (it will not be used by this module anymore).
351
352 This is useful with some push-type services, where, after the initial
353 headers, an interactive protocol is used (typical example would be the
354 push-style twitter API which starts a JSON/XML stream).
355
356 If you think you need this, first have a look at C<on_body>, to see if
357 that doesn't solve your problem in a better way.
358
359 =item persistent => $boolean
360
361 Try to create/reuse a persistent connection. When this flag is set
362 (default: true for idempotent requests, false for all others), then
363 C<http_request> tries to re-use an existing (previously-created)
364 persistent connection to same host (i.e. identical URL scheme, hostname,
365 port and sessionid) and, failing that, tries to create a new one.
366
367 Requests failing in certain ways will be automatically retried once, which
368 is dangerous for non-idempotent requests, which is why it defaults to off
369 for them. The reason for this is because the bozos who designed HTTP/1.1
370 made it impossible to distinguish between a fatal error and a normal
371 connection timeout, so you never know whether there was a problem with
372 your request or not.
373
374 When reusing an existent connection, many parameters (such as TLS context)
375 will be ignored. See the C<sessionid> parameter for a workaround.
376
377 =item keepalive => $boolean
378
379 Only used when C<persistent> is also true. This parameter decides whether
380 C<http_request> tries to handshake a HTTP/1.0-style keep-alive connection
381 (as opposed to only a HTTP/1.1 persistent connection).
382
383 The default is true, except when using a proxy, in which case it defaults
384 to false, as HTTP/1.0 proxies cannot support this in a meaningful way.
385
386 =item handle_params => { key => value ... }
387
388 The key-value pairs in this hash will be passed to any L<AnyEvent::Handle>
389 constructor that is called - not all requests will create a handle, and
390 sometimes more than one is created, so this parameter is only good for
391 setting hints.
392
393 Example: set the maximum read size to 4096, to potentially conserve memory
394 at the cost of speed.
395
396 handle_params => {
397 max_read_size => 4096,
398 },
399
400 =back
401
402 Example: do a simple HTTP GET request for http://www.nethype.de/ and print
403 the response body.
404
405 http_request GET => "http://www.nethype.de/", sub {
406 my ($body, $hdr) = @_;
407 print "$body\n";
408 };
409
410 Example: do a HTTP HEAD request on https://www.google.com/, use a
411 timeout of 30 seconds.
412
413 http_request
414 HEAD => "https://www.google.com",
415 headers => { "user-agent" => "MySearchClient 1.0" },
416 timeout => 30,
417 sub {
418 my ($body, $hdr) = @_;
419 use Data::Dumper;
420 print Dumper $hdr;
421 }
422 ;
423
424 Example: do another simple HTTP GET request, but immediately try to
425 cancel it.
426
427 my $request = http_request GET => "http://www.nethype.de/", sub {
428 my ($body, $hdr) = @_;
429 print "$body\n";
430 };
431
432 undef $request;
433
434 =cut
435
436 #############################################################################
437 # wait queue/slots
438
439 sub _slot_schedule;
440 sub _slot_schedule($) {
441 my $host = shift;
442
443 while ($CO_SLOT{$host}[0] < $MAX_PER_HOST) {
444 if (my $cb = shift @{ $CO_SLOT{$host}[1] }) {
445 # somebody wants that slot
446 ++$CO_SLOT{$host}[0];
447 ++$ACTIVE;
448
449 $cb->(AnyEvent::Util::guard {
450 --$ACTIVE;
451 --$CO_SLOT{$host}[0];
452 _slot_schedule $host;
453 });
454 } else {
455 # nobody wants the slot, maybe we can forget about it
456 delete $CO_SLOT{$host} unless $CO_SLOT{$host}[0];
457 last;
458 }
459 }
460 }
461
462 # wait for a free slot on host, call callback
463 sub _get_slot($$) {
464 push @{ $CO_SLOT{$_[0]}[1] }, $_[1];
465
466 _slot_schedule $_[0];
467 }
468
469 #############################################################################
470 # cookie handling
471
472 # expire cookies
473 sub cookie_jar_expire($;$) {
474 my ($jar, $session_end) = @_;
475
476 %$jar = () if $jar->{version} != 2;
477
478 my $anow = AE::now;
479
480 while (my ($chost, $paths) = each %$jar) {
481 next unless ref $paths;
482
483 while (my ($cpath, $cookies) = each %$paths) {
484 while (my ($cookie, $kv) = each %$cookies) {
485 if (exists $kv->{_expires}) {
486 delete $cookies->{$cookie}
487 if $anow > $kv->{_expires};
488 } elsif ($session_end) {
489 delete $cookies->{$cookie};
490 }
491 }
492
493 delete $paths->{$cpath}
494 unless %$cookies;
495 }
496
497 delete $jar->{$chost}
498 unless %$paths;
499 }
500 }
501
502 # extract cookies from jar
503 sub cookie_jar_extract($$$$) {
504 my ($jar, $scheme, $host, $path) = @_;
505
506 %$jar = () if $jar->{version} != 2;
507
508 $host = AnyEvent::Util::idn_to_ascii $host
509 if $host =~ /[^\x00-\x7f]/;
510
511 my @cookies;
512
513 while (my ($chost, $paths) = each %$jar) {
514 next unless ref $paths;
515
516 # exact match or suffix including . match
517 $chost eq $host or ".$chost" eq substr $host, -1 - length $chost
518 or next;
519
520 while (my ($cpath, $cookies) = each %$paths) {
521 next unless $cpath eq substr $path, 0, length $cpath;
522
523 while (my ($cookie, $kv) = each %$cookies) {
524 next if $scheme ne "https" && exists $kv->{secure};
525
526 if (exists $kv->{_expires} and AE::now > $kv->{_expires}) {
527 delete $cookies->{$cookie};
528 next;
529 }
530
531 my $value = $kv->{value};
532
533 if ($value =~ /[=;,[:space:]]/) {
534 $value =~ s/([\\"])/\\$1/g;
535 $value = "\"$value\"";
536 }
537
538 push @cookies, "$cookie=$value";
539 }
540 }
541 }
542
543 \@cookies
544 }
545
546 # parse set_cookie header into jar
547 sub cookie_jar_set_cookie($$$$) {
548 my ($jar, $set_cookie, $host, $date) = @_;
549
550 %$jar = () if $jar->{version} != 2;
551
552 my $anow = int AE::now;
553 my $snow; # server-now
554
555 for ($set_cookie) {
556 # parse NAME=VALUE
557 my @kv;
558
559 # expires is not http-compliant in the original cookie-spec,
560 # we support the official date format and some extensions
561 while (
562 m{
563 \G\s*
564 (?:
565 expires \s*=\s* ([A-Z][a-z][a-z]+,\ [^,;]+)
566 | ([^=;,[:space:]]+) (?: \s*=\s* (?: "((?:[^\\"]+|\\.)*)" | ([^;,[:space:]]*) ) )?
567 )
568 }gcxsi
569 ) {
570 my $name = $2;
571 my $value = $4;
572
573 if (defined $1) {
574 # expires
575 $name = "expires";
576 $value = $1;
577 } elsif (defined $3) {
578 # quoted
579 $value = $3;
580 $value =~ s/\\(.)/$1/gs;
581 }
582
583 push @kv, @kv ? lc $name : $name, $value;
584
585 last unless /\G\s*;/gc;
586 }
587
588 last unless @kv;
589
590 my $name = shift @kv;
591 my %kv = (value => shift @kv, @kv);
592
593 if (exists $kv{"max-age"}) {
594 $kv{_expires} = $anow + delete $kv{"max-age"};
595 } elsif (exists $kv{expires}) {
596 $snow ||= parse_date ($date) || $anow;
597 $kv{_expires} = $anow + (parse_date (delete $kv{expires}) - $snow);
598 } else {
599 delete $kv{_expires};
600 }
601
602 my $cdom;
603 my $cpath = (delete $kv{path}) || "/";
604
605 if (exists $kv{domain}) {
606 $cdom = $kv{domain};
607
608 $cdom =~ s/^\.?/./; # make sure it starts with a "."
609
610 next if $cdom =~ /\.$/;
611
612 # this is not rfc-like and not netscape-like. go figure.
613 my $ndots = $cdom =~ y/.//;
614 next if $ndots < ($cdom =~ /\.[^.][^.]\.[^.][^.]$/ ? 3 : 2);
615
616 $cdom = substr $cdom, 1; # remove initial .
617 } else {
618 $cdom = $host;
619 }
620
621 # store it
622 $jar->{version} = 2;
623 $jar->{lc $cdom}{$cpath}{$name} = \%kv;
624
625 redo if /\G\s*,/gc;
626 }
627 }
628
629 #############################################################################
630 # keepalive/persistent connection cache
631
632 # fetch a connection from the keepalive cache
633 sub ka_fetch($) {
634 my $ka_key = shift;
635
636 my $hdl = pop @{ $KA_CACHE{$ka_key} }; # currently we reuse the MOST RECENTLY USED connection
637 delete $KA_CACHE{$ka_key}
638 unless @{ $KA_CACHE{$ka_key} };
639
640 $hdl
641 }
642
643 sub ka_store($$) {
644 my ($ka_key, $hdl) = @_;
645
646 my $kaa = $KA_CACHE{$ka_key} ||= [];
647
648 my $destroy = sub {
649 my @ka = grep $_ != $hdl, @{ $KA_CACHE{$ka_key} };
650
651 $hdl->destroy;
652
653 @ka
654 ? $KA_CACHE{$ka_key} = \@ka
655 : delete $KA_CACHE{$ka_key};
656 };
657
658 # on error etc., destroy
659 $hdl->on_error ($destroy);
660 $hdl->on_eof ($destroy);
661 $hdl->on_read ($destroy);
662 $hdl->timeout ($PERSISTENT_TIMEOUT);
663
664 push @$kaa, $hdl;
665 shift @$kaa while @$kaa > $MAX_PER_HOST;
666 }
667
668 #############################################################################
669 # utilities
670
671 # continue to parse $_ for headers and place them into the arg
672 sub _parse_hdr() {
673 my %hdr;
674
675 # things seen, not parsed:
676 # p3pP="NON CUR OTPi OUR NOR UNI"
677
678 $hdr{lc $1} .= ",$2"
679 while /\G
680 ([^:\000-\037]*):
681 [\011\040]*
682 ((?: [^\012]+ | \012[\011\040] )*)
683 \012
684 /gxc;
685
686 /\G$/
687 or return;
688
689 # remove the "," prefix we added to all headers above
690 substr $_, 0, 1, ""
691 for values %hdr;
692
693 \%hdr
694 }
695
696 #############################################################################
697 # http_get
698
699 our $qr_nlnl = qr{(?<![^\012])\015?\012};
700
701 our $TLS_CTX_LOW = { cache => 1, sslv2 => 1 };
702 our $TLS_CTX_HIGH = { cache => 1, verify => 1, verify_peername => "https" };
703
704 # maybe it should just become a normal object :/
705
706 sub _destroy_state(\%) {
707 my ($state) = @_;
708
709 $state->{handle}->destroy if $state->{handle};
710 %$state = ();
711 }
712
713 sub _error(\%$$) {
714 my ($state, $cb, $hdr) = @_;
715
716 &_destroy_state ($state);
717
718 $cb->(undef, $hdr);
719 ()
720 }
721
722 our %IDEMPOTENT = (
723 DELETE => 1,
724 GET => 1,
725 QUERY => 1,
726 HEAD => 1,
727 OPTIONS => 1,
728 PUT => 1,
729 TRACE => 1,
730
731 ACL => 1,
732 "BASELINE-CONTROL" => 1,
733 BIND => 1,
734 CHECKIN => 1,
735 CHECKOUT => 1,
736 COPY => 1,
737 LABEL => 1,
738 LINK => 1,
739 MERGE => 1,
740 MKACTIVITY => 1,
741 MKCALENDAR => 1,
742 MKCOL => 1,
743 MKREDIRECTREF => 1,
744 MKWORKSPACE => 1,
745 MOVE => 1,
746 ORDERPATCH => 1,
747 PRI => 1,
748 PROPFIND => 1,
749 PROPPATCH => 1,
750 REBIND => 1,
751 REPORT => 1,
752 SEARCH => 1,
753 UNBIND => 1,
754 UNCHECKOUT => 1,
755 UNLINK => 1,
756 UNLOCK => 1,
757 UPDATE => 1,
758 UPDATEREDIRECTREF => 1,
759 "VERSION-CONTROL" => 1,
760 );
761
762 sub http_request($$@) {
763 my $cb = pop;
764 my ($method, $url, %arg) = @_;
765
766 my %hdr;
767
768 $arg{tls_ctx} = $TLS_CTX_LOW if $arg{tls_ctx} eq "low" || !exists $arg{tls_ctx};
769 $arg{tls_ctx} = $TLS_CTX_HIGH if $arg{tls_ctx} eq "high";
770
771 $method = uc $method;
772
773 if (my $hdr = $arg{headers}) {
774 while (my ($k, $v) = each %$hdr) {
775 $hdr{lc $k} = $v;
776 }
777 }
778
779 # pseudo headers for all subsequent responses
780 my @pseudo = (URL => $url);
781 push @pseudo, Redirect => delete $arg{Redirect} if exists $arg{Redirect};
782
783 my $recurse = exists $arg{recurse} ? delete $arg{recurse} : $MAX_RECURSE;
784
785 return $cb->(undef, { @pseudo, Status => 599, Reason => "Too many redirections" })
786 if $recurse < 0;
787
788 my $proxy = exists $arg{proxy} ? $arg{proxy} : $PROXY;
789 my $timeout = $arg{timeout} || $TIMEOUT;
790
791 my ($uscheme, $uauthority, $upath, $query, undef) = # ignore fragment
792 $url =~ m|^([^:]+):(?://([^/?#]*))?([^?#]*)(?:(\?[^#]*))?(?:#(.*))?$|;
793
794 $uscheme = lc $uscheme;
795
796 my $uport = $uscheme eq "http" ? 80
797 : $uscheme eq "https" ? 443
798 : return $cb->(undef, { @pseudo, Status => 599, Reason => "Only http and https URL schemes supported" });
799
800 $uauthority =~ /^(?: .*\@ )? ([^\@]+?) (?: : (\d+) )?$/x
801 or return $cb->(undef, { @pseudo, Status => 599, Reason => "Unparsable URL" });
802
803 my $uhost = lc $1;
804 $uport = $2 if defined $2;
805
806 $hdr{host} = defined $2 ? "$uhost:$2" : "$uhost"
807 unless exists $hdr{host};
808
809 $uhost =~ s/^\[(.*)\]$/$1/;
810 $upath .= $query if length $query;
811
812 $upath =~ s%^/?%/%;
813
814 # cookie processing
815 if (my $jar = $arg{cookie_jar}) {
816 my $cookies = cookie_jar_extract $jar, $uscheme, $uhost, $upath;
817
818 $hdr{cookie} = join "; ", @$cookies
819 if @$cookies;
820 }
821
822 my ($rhost, $rport, $rscheme, $rpath); # request host, port, path
823
824 if ($proxy) {
825 ($rpath, $rhost, $rport, $rscheme) = ($url, @$proxy);
826
827 $rscheme = "http" unless defined $rscheme;
828
829 # don't support https requests over https-proxy transport,
830 # can't be done with tls as spec'ed, unless you double-encrypt.
831 $rscheme = "http" if $uscheme eq "https" && $rscheme eq "https";
832
833 $rhost = lc $rhost;
834 $rscheme = lc $rscheme;
835 } else {
836 ($rhost, $rport, $rscheme, $rpath) = ($uhost, $uport, $uscheme, $upath);
837 }
838
839 # leave out fragment and query string, just a heuristic
840 $hdr{referer} = "$uscheme://$uauthority$upath" unless exists $hdr{referer};
841 $hdr{"user-agent"} = $USERAGENT unless exists $hdr{"user-agent"};
842
843 $hdr{"content-length"} = length $arg{body}
844 if length $arg{body} || $method ne "GET";
845
846 my $idempotent = $IDEMPOTENT{$method};
847
848 # default value for keepalive is true iff the request is for an idempotent method
849 my $persistent = exists $arg{persistent} ? !!$arg{persistent} : $idempotent;
850 my $keepalive = exists $arg{keepalive} ? !!$arg{keepalive} : !$proxy;
851 my $was_persistent; # true if this is actually a recycled connection
852
853 # the key to use in the keepalive cache
854 my $ka_key = "$uscheme\x00$uhost\x00$uport\x00$arg{sessionid}";
855
856 $hdr{connection} = ($persistent ? $keepalive ? "keep-alive, " : "" : "close, ") . "Te"; #1.1
857 $hdr{te} = "trailers" unless exists $hdr{te}; #1.1
858
859 my %state = (connect_guard => 1);
860
861 my $ae_error = 595; # connecting
862
863 # handle actual, non-tunneled, request
864 my $handle_actual_request = sub {
865 $ae_error = 596; # request phase
866
867 my $hdl = $state{handle};
868
869 $hdl->starttls ("connect") if $uscheme eq "https" && !exists $hdl->{tls};
870
871 # send request
872 $hdl->push_write (
873 "$method $rpath HTTP/1.1\015\012"
874 . (join "", map "\u$_: $hdr{$_}\015\012", grep defined $hdr{$_}, keys %hdr)
875 . "\015\012"
876 . $arg{body}
877 );
878
879 # return if error occurred during push_write()
880 return unless %state;
881
882 # reduce memory usage, save a kitten, also re-use it for the response headers.
883 %hdr = ();
884
885 # status line and headers
886 $state{read_response} = sub {
887 return unless %state;
888
889 for ("$_[1]") {
890 y/\015//d; # weed out any \015, as they show up in the weirdest of places.
891
892 /^HTTP\/0*([0-9\.]+) \s+ ([0-9]{3}) (?: \s+ ([^\012]*) )? \012/gxci
893 or return _error %state, $cb, { @pseudo, Status => 599, Reason => "Invalid server response" };
894
895 # 100 Continue handling
896 # should not happen as we don't send expect: 100-continue,
897 # but we handle it just in case.
898 # since we send the request body regardless, if we get an error
899 # we are out of-sync, which we currently do NOT handle correctly.
900 return $state{handle}->push_read (line => $qr_nlnl, $state{read_response})
901 if $2 eq 100;
902
903 push @pseudo,
904 HTTPVersion => $1,
905 Status => $2,
906 Reason => $3,
907 ;
908
909 my $hdr = _parse_hdr
910 or return _error %state, $cb, { @pseudo, Status => 599, Reason => "Garbled response headers" };
911
912 %hdr = (%$hdr, @pseudo);
913 }
914
915 # redirect handling
916 # relative uri handling forced by microsoft and other shitheads.
917 # we give our best and fall back to URI if available.
918 if (exists $hdr{location}) {
919 my $loc = $hdr{location};
920
921 if ($loc =~ m%^//%) { # //
922 $loc = "$uscheme:$loc";
923
924 } elsif ($loc eq "") {
925 $loc = $url;
926
927 } elsif ($loc !~ /^(?: $ | [^:\/?\#]+ : )/x) { # anything "simple"
928 $loc =~ s/^\.\/+//;
929
930 if ($loc !~ m%^[.?#]%) {
931 my $prefix = "$uscheme://$uauthority";
932
933 unless ($loc =~ s/^\///) {
934 $prefix .= $upath;
935 $prefix =~ s/\/[^\/]*$//;
936 }
937
938 $loc = "$prefix/$loc";
939
940 } elsif (eval { require URI }) { # uri
941 $loc = URI->new_abs ($loc, $url)->as_string;
942
943 } else {
944 return _error %state, $cb, { @pseudo, Status => 599, Reason => "Cannot parse Location (URI module missing)" };
945 #$hdr{Status} = 599;
946 #$hdr{Reason} = "Unparsable Redirect (URI module missing)";
947 #$recurse = 0;
948 }
949 }
950
951 $hdr{location} = $loc;
952 }
953
954 my $redirect;
955
956 if ($recurse) {
957 my $status = $hdr{Status};
958
959 # industry standard is to redirect POST as GET for
960 # 301, 302 and 303, in contrast to HTTP/1.0 and 1.1.
961 # also, the UA should ask the user for 301 and 307 and POST,
962 # industry standard seems to be to simply follow.
963 # we go with the industry standard. 308 is defined
964 # by rfc7538
965 if ($status == 301 or $status == 302 or $status == 303) {
966 $redirect = 1;
967 # HTTP/1.1 is unclear on how to mutate the method
968 unless ($method eq "HEAD") {
969 $method = "GET";
970 delete $arg{body};
971 }
972 } elsif ($status == 307 or $status == 308) {
973 $redirect = 1;
974 }
975 }
976
977 my $finish = sub { # ($data, $err_status, $err_reason[, $persistent])
978 if ($state{handle}) {
979 # handle keepalive
980 if (
981 $persistent
982 && $_[3]
983 && ($hdr{HTTPVersion} < 1.1
984 ? $hdr{connection} =~ /\bkeep-?alive\b/i
985 : $hdr{connection} !~ /\bclose\b/i)
986 ) {
987 ka_store $ka_key, delete $state{handle};
988 } else {
989 # no keepalive, destroy the handle
990 $state{handle}->destroy;
991 }
992 }
993
994 %state = ();
995
996 if (defined $_[1]) {
997 $hdr{OrigStatus} = $hdr{Status}; $hdr{Status} = $_[1];
998 $hdr{OrigReason} = $hdr{Reason}; $hdr{Reason} = $_[2];
999 }
1000
1001 # set-cookie processing
1002 if ($arg{cookie_jar}) {
1003 cookie_jar_set_cookie $arg{cookie_jar}, $hdr{"set-cookie"}, $uhost, $hdr{date};
1004 }
1005
1006 if ($redirect && exists $hdr{location}) {
1007 # we ignore any errors, as it is very common to receive
1008 # Content-Length != 0 but no actual body
1009 # we also access %hdr, as $_[1] might be an erro
1010 $state{recurse} =
1011 http_request (
1012 $method => $hdr{location},
1013 %arg,
1014 recurse => $recurse - 1,
1015 Redirect => [$_[0], \%hdr],
1016 sub {
1017 %state = ();
1018 &$cb
1019 },
1020 );
1021 } else {
1022 $cb->($_[0], \%hdr);
1023 }
1024 };
1025
1026 $ae_error = 597; # body phase
1027
1028 my $chunked = $hdr{"transfer-encoding"} =~ /\bchunked\b/i; # not quite correct...
1029
1030 my $len = $chunked ? undef : $hdr{"content-length"};
1031
1032 # body handling, many different code paths
1033 # - no body expected
1034 # - want_body_handle
1035 # - te chunked
1036 # - 2x length known (with or without on_body)
1037 # - 2x length not known (with or without on_body)
1038 if (!$redirect && $arg{on_header} && !$arg{on_header}(\%hdr)) {
1039 $finish->(undef, 598 => "Request cancelled by on_header");
1040 } elsif (
1041 $hdr{Status} =~ /^(?:1..|204|205|304)$/
1042 or $method eq "HEAD"
1043 or (defined $len && $len == 0) # == 0, not !, because "0 " is true
1044 ) {
1045 # no body
1046 $finish->("", undef, undef, 1);
1047
1048 } elsif (!$redirect && $arg{want_body_handle}) {
1049 $_[0]->on_eof (undef);
1050 $_[0]->on_error (undef);
1051 $_[0]->on_read (undef);
1052
1053 $finish->(delete $state{handle});
1054
1055 } elsif ($chunked) {
1056 my $cl = 0;
1057 my $body = "";
1058 my $on_body = (!$redirect && $arg{on_body}) || sub { $body .= shift; 1 };
1059
1060 $state{read_chunk} = sub {
1061 $_[1] =~ /^([0-9a-fA-F]+)/
1062 or return $finish->(undef, $ae_error => "Garbled chunked transfer encoding");
1063
1064 my $len = hex $1;
1065
1066 if ($len) {
1067 $cl += $len;
1068
1069 $_[0]->push_read (chunk => $len, sub {
1070 $on_body->($_[1], \%hdr)
1071 or return $finish->(undef, 598 => "Request cancelled by on_body");
1072
1073 $_[0]->push_read (line => sub {
1074 length $_[1]
1075 and return $finish->(undef, $ae_error => "Garbled chunked transfer encoding");
1076 $_[0]->push_read (line => $state{read_chunk});
1077 });
1078 });
1079 } else {
1080 $hdr{"content-length"} ||= $cl;
1081
1082 $_[0]->push_read (line => $qr_nlnl, sub {
1083 if (length $_[1]) {
1084 for ("$_[1]") {
1085 y/\015//d; # weed out any \015, as they show up in the weirdest of places.
1086
1087 my $hdr = _parse_hdr
1088 or return $finish->(undef, $ae_error => "Garbled response trailers");
1089
1090 %hdr = (%hdr, %$hdr);
1091 }
1092 }
1093
1094 $finish->($body, undef, undef, 1);
1095 });
1096 }
1097 };
1098
1099 $_[0]->push_read (line => $state{read_chunk});
1100
1101 } elsif (!$redirect && $arg{on_body}) {
1102 if (defined $len) {
1103 $_[0]->on_read (sub {
1104 $len -= length $_[0]{rbuf};
1105
1106 $arg{on_body}(delete $_[0]{rbuf}, \%hdr)
1107 or return $finish->(undef, 598 => "Request cancelled by on_body");
1108
1109 $len > 0
1110 or $finish->("", undef, undef, 1);
1111 });
1112 } else {
1113 $_[0]->on_eof (sub {
1114 $finish->("");
1115 });
1116 $_[0]->on_read (sub {
1117 $arg{on_body}(delete $_[0]{rbuf}, \%hdr)
1118 or $finish->(undef, 598 => "Request cancelled by on_body");
1119 });
1120 }
1121 } else {
1122 $_[0]->on_eof (undef);
1123
1124 if (defined $len) {
1125 $_[0]->on_read (sub {
1126 $finish->((substr delete $_[0]{rbuf}, 0, $len, ""), undef, undef, 1)
1127 if $len <= length $_[0]{rbuf};
1128 });
1129 } else {
1130 $_[0]->on_error (sub {
1131 ($! == Errno::EPIPE || !$!)
1132 ? $finish->(delete $_[0]{rbuf})
1133 : $finish->(undef, $ae_error => $_[2]);
1134 });
1135 $_[0]->on_read (sub { });
1136 }
1137 }
1138 };
1139
1140 # if keepalive is enabled, then the server closing the connection
1141 # before a response can happen legally - we retry on idempotent methods.
1142 if ($was_persistent && $idempotent) {
1143 my $old_eof = $hdl->{on_eof};
1144 $hdl->{on_eof} = sub {
1145 _destroy_state %state;
1146
1147 %state = ();
1148 $state{recurse} =
1149 http_request (
1150 $method => $url,
1151 %arg,
1152 recurse => $recurse - 1,
1153 persistent => 0,
1154 sub {
1155 %state = ();
1156 &$cb
1157 }
1158 );
1159 };
1160 $hdl->on_read (sub {
1161 return unless %state;
1162
1163 # as soon as we receive something, a connection close
1164 # once more becomes a hard error
1165 $hdl->{on_eof} = $old_eof;
1166 $hdl->push_read (line => $qr_nlnl, $state{read_response});
1167 });
1168 } else {
1169 $hdl->push_read (line => $qr_nlnl, $state{read_response});
1170 }
1171 };
1172
1173 my $prepare_handle = sub {
1174 my ($hdl) = $state{handle};
1175
1176 $hdl->on_error (sub {
1177 _error %state, $cb, { @pseudo, Status => $ae_error, Reason => $_[2] };
1178 });
1179 $hdl->on_eof (sub {
1180 _error %state, $cb, { @pseudo, Status => $ae_error, Reason => "Unexpected end-of-file" };
1181 });
1182 $hdl->timeout_reset;
1183 $hdl->timeout ($timeout);
1184 };
1185
1186 # connected to proxy (or origin server)
1187 my $connect_cb = sub {
1188 my $fh = shift
1189 or return _error %state, $cb, { @pseudo, Status => $ae_error, Reason => "$!" };
1190
1191 return unless delete $state{connect_guard};
1192
1193 # get handle
1194 $state{handle} = new AnyEvent::Handle
1195 %{ $arg{handle_params} },
1196 fh => $fh,
1197 peername => $uhost,
1198 tls_ctx => $arg{tls_ctx},
1199 ;
1200
1201 $prepare_handle->();
1202
1203 #$state{handle}->starttls ("connect") if $rscheme eq "https";
1204
1205 # now handle proxy-CONNECT method
1206 if ($proxy && $uscheme eq "https") {
1207 # oh dear, we have to wrap it into a connect request
1208
1209 my $auth = exists $hdr{"proxy-authorization"}
1210 ? "proxy-authorization: " . (delete $hdr{"proxy-authorization"}) . "\015\012"
1211 : "";
1212
1213 # maybe re-use $uauthority with patched port?
1214 $state{handle}->push_write ("CONNECT $uhost:$uport HTTP/1.0\015\012$auth\015\012");
1215 $state{handle}->push_read (line => $qr_nlnl, sub {
1216 $_[1] =~ /^HTTP\/([0-9\.]+) \s+ ([0-9]{3}) (?: \s+ ([^\015\012]*) )?/ix
1217 or return _error %state, $cb, { @pseudo, Status => 599, Reason => "Invalid proxy connect response ($_[1])" };
1218
1219 if ($2 == 200) {
1220 $rpath = $upath;
1221 $handle_actual_request->();
1222 } else {
1223 _error %state, $cb, { @pseudo, Status => $2, Reason => $3 };
1224 }
1225 });
1226 } else {
1227 delete $hdr{"proxy-authorization"} unless $proxy;
1228
1229 $handle_actual_request->();
1230 }
1231 };
1232
1233 _get_slot $uhost, sub {
1234 $state{slot_guard} = shift;
1235
1236 return unless $state{connect_guard};
1237
1238 # try to use an existing keepalive connection, but only if we, ourselves, plan
1239 # on a keepalive request (in theory, this should be a separate config option).
1240 if ($persistent && $KA_CACHE{$ka_key}) {
1241 $was_persistent = 1;
1242
1243 $state{handle} = ka_fetch $ka_key;
1244 # $state{handle}->destroyed
1245 # and die "AnyEvent::HTTP: unexpectedly got a destructed handle (1), please report.";#d#
1246 $prepare_handle->();
1247 # $state{handle}->destroyed
1248 # and die "AnyEvent::HTTP: unexpectedly got a destructed handle (2), please report.";#d#
1249 $rpath = $upath;
1250 $handle_actual_request->();
1251
1252 } else {
1253 my $tcp_connect = $arg{tcp_connect}
1254 || do { require AnyEvent::Socket; \&AnyEvent::Socket::tcp_connect };
1255
1256 $state{connect_guard} = $tcp_connect->($rhost, $rport, $connect_cb, $arg{on_prepare} || sub { $timeout });
1257 }
1258 };
1259
1260 defined wantarray && AnyEvent::Util::guard { _destroy_state %state }
1261 }
1262
1263 sub http_get($@) {
1264 unshift @_, "GET";
1265 &http_request
1266 }
1267
1268 sub http_head($@) {
1269 unshift @_, "HEAD";
1270 &http_request
1271 }
1272
1273 sub http_post($$@) {
1274 my $url = shift;
1275 unshift @_, "POST", $url, "body";
1276 &http_request
1277 }
1278
1279 =back
1280
1281 =head2 DNS CACHING
1282
1283 AnyEvent::HTTP uses the AnyEvent::Socket::tcp_connect function for
1284 the actual connection, which in turn uses AnyEvent::DNS to resolve
1285 hostnames. The latter is a simple stub resolver and does no caching
1286 on its own. If you want DNS caching, you currently have to provide
1287 your own default resolver (by storing a suitable resolver object in
1288 C<$AnyEvent::DNS::RESOLVER>) or your own C<tcp_connect> callback.
1289
1290 =head2 GLOBAL FUNCTIONS AND VARIABLES
1291
1292 =over 4
1293
1294 =item AnyEvent::HTTP::set_proxy "proxy-url"
1295
1296 Sets the default proxy server to use. The proxy-url must begin with a
1297 string of the form C<http://host:port>, croaks otherwise.
1298
1299 To clear an already-set proxy, use C<undef>.
1300
1301 When AnyEvent::HTTP is loaded for the first time it will query the
1302 default proxy from the operating system, currently by looking at
1303 C<$ENV{http_proxy>}.
1304
1305 =item AnyEvent::HTTP::cookie_jar_expire $jar[, $session_end]
1306
1307 Remove all cookies from the cookie jar that have been expired. If
1308 C<$session_end> is given and true, then additionally remove all session
1309 cookies.
1310
1311 You should call this function (with a true C<$session_end>) before you
1312 save cookies to disk, and you should call this function after loading them
1313 again. If you have a long-running program you can additionally call this
1314 function from time to time.
1315
1316 A cookie jar is initially an empty hash-reference that is managed by this
1317 module. Its format is subject to change, but currently it is as follows:
1318
1319 The key C<version> has to contain C<2>, otherwise the hash gets
1320 cleared. All other keys are hostnames or IP addresses pointing to
1321 hash-references. The key for these inner hash references is the
1322 server path for which this cookie is meant, and the values are again
1323 hash-references. Each key of those hash-references is a cookie name, and
1324 the value, you guessed it, is another hash-reference, this time with the
1325 key-value pairs from the cookie, except for C<expires> and C<max-age>,
1326 which have been replaced by a C<_expires> key that contains the cookie
1327 expiry timestamp. Session cookies are indicated by not having an
1328 C<_expires> key.
1329
1330 Here is an example of a cookie jar with a single cookie, so you have a
1331 chance of understanding the above paragraph:
1332
1333 {
1334 version => 2,
1335 "10.0.0.1" => {
1336 "/" => {
1337 "mythweb_id" => {
1338 _expires => 1293917923,
1339 value => "ooRung9dThee3ooyXooM1Ohm",
1340 },
1341 },
1342 },
1343 }
1344
1345 =item $date = AnyEvent::HTTP::format_date $timestamp
1346
1347 Takes a POSIX timestamp (seconds since the epoch) and formats it as a HTTP
1348 Date (RFC 2616).
1349
1350 =item $timestamp = AnyEvent::HTTP::parse_date $date
1351
1352 Takes a HTTP Date (RFC 2616) or a Cookie date (netscape cookie spec) or a
1353 bunch of minor variations of those, and returns the corresponding POSIX
1354 timestamp, or C<undef> if the date cannot be parsed.
1355
1356 =item $AnyEvent::HTTP::MAX_RECURSE
1357
1358 The default value for the C<recurse> request parameter (default: C<10>).
1359
1360 =item $AnyEvent::HTTP::TIMEOUT
1361
1362 The default timeout for connection operations (default: C<300>).
1363
1364 =item $AnyEvent::HTTP::USERAGENT
1365
1366 The default value for the C<User-Agent> header (the default is
1367 C<Mozilla/5.0 (compatible; U; AnyEvent-HTTP/$VERSION; +http://software.schmorp.de/pkg/AnyEvent)>).
1368
1369 =item $AnyEvent::HTTP::MAX_PER_HOST
1370
1371 The maximum number of concurrent connections to the same host (identified
1372 by the hostname). If the limit is exceeded, then additional requests
1373 are queued until previous connections are closed. Both persistent and
1374 non-persistent connections are counted in this limit.
1375
1376 The default value for this is C<4>, and it is highly advisable to not
1377 increase it much.
1378
1379 For comparison: the RFC's recommend 4 non-persistent or 2 persistent
1380 connections, older browsers used 2, newer ones (such as firefox 3)
1381 typically use 6, and Opera uses 8 because like, they have the fastest
1382 browser and give a shit for everybody else on the planet.
1383
1384 =item $AnyEvent::HTTP::PERSISTENT_TIMEOUT
1385
1386 The time after which idle persistent connections get closed by
1387 AnyEvent::HTTP (default: C<3>).
1388
1389 =item $AnyEvent::HTTP::ACTIVE
1390
1391 The number of active connections. This is not the number of currently
1392 running requests, but the number of currently open and non-idle TCP
1393 connections. This number can be useful for load-leveling.
1394
1395 =back
1396
1397 =cut
1398
1399 our @month = qw(Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec);
1400 our @weekday = qw(Sun Mon Tue Wed Thu Fri Sat);
1401
1402 sub format_date($) {
1403 my ($time) = @_;
1404
1405 # RFC 822/1123 format
1406 my ($S, $M, $H, $mday, $mon, $year, $wday, $yday, undef) = gmtime $time;
1407
1408 sprintf "%s, %02d %s %04d %02d:%02d:%02d GMT",
1409 $weekday[$wday], $mday, $month[$mon], $year + 1900,
1410 $H, $M, $S;
1411 }
1412
1413 sub parse_date($) {
1414 my ($date) = @_;
1415
1416 my ($d, $m, $y, $H, $M, $S);
1417
1418 if ($date =~ /^[A-Z][a-z][a-z]+, ([0-9][0-9]?)[\- ]([A-Z][a-z][a-z])[\- ]([0-9][0-9][0-9][0-9]) ([0-9][0-9]?):([0-9][0-9]?):([0-9][0-9]?) GMT$/) {
1419 # RFC 822/1123, required by RFC 2616 (with " ")
1420 # cookie dates (with "-")
1421
1422 ($d, $m, $y, $H, $M, $S) = ($1, $2, $3, $4, $5, $6);
1423
1424 } elsif ($date =~ /^[A-Z][a-z][a-z]+, ([0-9][0-9]?)-([A-Z][a-z][a-z])-([0-9][0-9]) ([0-9][0-9]?):([0-9][0-9]?):([0-9][0-9]?) GMT$/) {
1425 # RFC 850
1426 ($d, $m, $y, $H, $M, $S) = ($1, $2, $3 < 69 ? $3 + 2000 : $3 + 1900, $4, $5, $6);
1427
1428 } elsif ($date =~ /^[A-Z][a-z][a-z]+ ([A-Z][a-z][a-z]) ([0-9 ]?[0-9]) ([0-9][0-9]?):([0-9][0-9]?):([0-9][0-9]?) ([0-9][0-9][0-9][0-9])$/) {
1429 # ISO C's asctime
1430 ($d, $m, $y, $H, $M, $S) = ($2, $1, $6, $3, $4, $5);
1431 }
1432 # other formats fail in the loop below
1433
1434 for (0..11) {
1435 if ($m eq $month[$_]) {
1436 require Time::Local;
1437 return eval { Time::Local::timegm ($S, $M, $H, $d, $_, $y) };
1438 }
1439 }
1440
1441 undef
1442 }
1443
1444 sub set_proxy($) {
1445 if (length $_[0]) {
1446 $_[0] =~ m%^(http):// ([^:/]+) (?: : (\d*) )?%ix
1447 or Carp::croak "$_[0]: invalid proxy URL";
1448 $PROXY = [$2, $3 || 3128, $1]
1449 } else {
1450 undef $PROXY;
1451 }
1452 }
1453
1454 # initialise proxy from environment
1455 eval {
1456 set_proxy $ENV{http_proxy};
1457 };
1458
1459 =head2 SHOWCASE
1460
1461 This section contains some more elaborate "real-world" examples or code
1462 snippets.
1463
1464 =head2 HTTP/1.1 FILE DOWNLOAD
1465
1466 Downloading files with HTTP can be quite tricky, especially when something
1467 goes wrong and you want to resume.
1468
1469 Here is a function that initiates and resumes a download. It uses the
1470 last modified time to check for file content changes, and works with many
1471 HTTP/1.0 servers as well, and usually falls back to a complete re-download
1472 on older servers.
1473
1474 It calls the completion callback with either C<undef>, which means a
1475 nonretryable error occurred, C<0> when the download was partial and should
1476 be retried, and C<1> if it was successful.
1477
1478 use AnyEvent::HTTP;
1479
1480 sub download($$$) {
1481 my ($url, $file, $cb) = @_;
1482
1483 open my $fh, "+<", $file
1484 or die "$file: $!";
1485
1486 my %hdr;
1487 my $ofs = 0;
1488
1489 if (stat $fh and -s _) {
1490 $ofs = -s _;
1491 warn "-s is ", $ofs;
1492 $hdr{"if-unmodified-since"} = AnyEvent::HTTP::format_date +(stat _)[9];
1493 $hdr{"range"} = "bytes=$ofs-";
1494 }
1495
1496 http_get $url,
1497 headers => \%hdr,
1498 on_header => sub {
1499 my ($hdr) = @_;
1500
1501 if ($hdr->{Status} == 200 && $ofs) {
1502 # resume failed
1503 truncate $fh, $ofs = 0;
1504 }
1505
1506 sysseek $fh, $ofs, 0;
1507
1508 1
1509 },
1510 on_body => sub {
1511 my ($data, $hdr) = @_;
1512
1513 if ($hdr->{Status} =~ /^2/) {
1514 length $data == syswrite $fh, $data
1515 or return; # abort on write errors
1516 }
1517
1518 1
1519 },
1520 sub {
1521 my (undef, $hdr) = @_;
1522
1523 my $status = $hdr->{Status};
1524
1525 if (my $time = AnyEvent::HTTP::parse_date $hdr->{"last-modified"}) {
1526 utime $time, $time, $fh;
1527 }
1528
1529 if ($status == 200 || $status == 206 || $status == 416) {
1530 # download ok || resume ok || file already fully downloaded
1531 $cb->(1, $hdr);
1532
1533 } elsif ($status == 412) {
1534 # file has changed while resuming, delete and retry
1535 unlink $file;
1536 $cb->(0, $hdr);
1537
1538 } elsif ($status == 500 or $status == 503 or $status =~ /^59/) {
1539 # retry later
1540 $cb->(0, $hdr);
1541
1542 } else {
1543 $cb->(undef, $hdr);
1544 }
1545 }
1546 ;
1547 }
1548
1549 download "http://server/somelargefile", "/tmp/somelargefile", sub {
1550 if ($_[0]) {
1551 print "OK!\n";
1552 } elsif (defined $_[0]) {
1553 print "please retry later\n";
1554 } else {
1555 print "ERROR\n";
1556 }
1557 };
1558
1559 =head3 SOCKS PROXIES
1560
1561 Socks proxies are not directly supported by AnyEvent::HTTP. You can
1562 compile your perl to support socks, or use an external program such as
1563 F<socksify> (dante) or F<tsocks> to make your program use a socks proxy
1564 transparently.
1565
1566 Alternatively, for AnyEvent::HTTP only, you can use your own
1567 C<tcp_connect> function that does the proxy handshake - here is an example
1568 that works with socks4a proxies:
1569
1570 use Errno;
1571 use AnyEvent::Util;
1572 use AnyEvent::Socket;
1573 use AnyEvent::Handle;
1574
1575 # host, port and username of/for your socks4a proxy
1576 my $socks_host = "10.0.0.23";
1577 my $socks_port = 9050;
1578 my $socks_user = "";
1579
1580 sub socks4a_connect {
1581 my ($host, $port, $connect_cb, $prepare_cb) = @_;
1582
1583 my $hdl = new AnyEvent::Handle
1584 connect => [$socks_host, $socks_port],
1585 on_prepare => sub { $prepare_cb->($_[0]{fh}) },
1586 on_error => sub { $connect_cb->() },
1587 ;
1588
1589 $hdl->push_write (pack "CCnNZ*Z*", 4, 1, $port, 1, $socks_user, $host);
1590
1591 $hdl->push_read (chunk => 8, sub {
1592 my ($hdl, $chunk) = @_;
1593 my ($status, $port, $ipn) = unpack "xCna4", $chunk;
1594
1595 if ($status == 0x5a) {
1596 $connect_cb->($hdl->{fh}, (format_address $ipn) . ":$port");
1597 } else {
1598 $! = Errno::ENXIO; $connect_cb->();
1599 }
1600 });
1601
1602 $hdl
1603 }
1604
1605 Use C<socks4a_connect> instead of C<tcp_connect> when doing C<http_request>s,
1606 possibly after switching off other proxy types:
1607
1608 AnyEvent::HTTP::set_proxy undef; # usually you do not want other proxies
1609
1610 http_get 'http://www.google.com', tcp_connect => \&socks4a_connect, sub {
1611 my ($data, $headers) = @_;
1612 ...
1613 };
1614
1615 =head1 SEE ALSO
1616
1617 L<AnyEvent>.
1618
1619 =head1 AUTHOR
1620
1621 Marc Lehmann <schmorp@schmorp.de>
1622 http://home.schmorp.de/
1623
1624 With many thanks to Дмитрий Шалашов, who provided countless
1625 testcases and bugreports.
1626
1627 =cut
1628
1629 1
1630