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Comparing AnyEvent-HTTP/HTTP.pm (file contents):
Revision 1.8 by root, Wed Jun 4 12:32:30 2008 UTC vs.
Revision 1.70 by root, Fri Dec 31 20:31:47 2010 UTC

3AnyEvent::HTTP - simple but non-blocking HTTP/HTTPS client 3AnyEvent::HTTP - simple but non-blocking HTTP/HTTPS client
4 4
5=head1 SYNOPSIS 5=head1 SYNOPSIS
6 6
7 use AnyEvent::HTTP; 7 use AnyEvent::HTTP;
8
9 http_get "http://www.nethype.de/", sub { print $_[1] };
10
11 # ... do something else here
8 12
9=head1 DESCRIPTION 13=head1 DESCRIPTION
10 14
11This module is an L<AnyEvent> user, you need to make sure that you use and 15This module is an L<AnyEvent> user, you need to make sure that you use and
12run a supported event loop. 16run a supported event loop.
13 17
18This module implements a simple, stateless and non-blocking HTTP
19client. It supports GET, POST and other request methods, cookies and more,
20all on a very low level. It can follow redirects supports proxies and
21automatically limits the number of connections to the values specified in
22the RFC.
23
24It should generally be a "good client" that is enough for most HTTP
25tasks. Simple tasks should be simple, but complex tasks should still be
26possible as the user retains control over request and response headers.
27
28The caller is responsible for authentication management, cookies (if
29the simplistic implementation in this module doesn't suffice), referer
30and other high-level protocol details for which this module offers only
31limited support.
32
14=head2 METHODS 33=head2 METHODS
15 34
16=over 4 35=over 4
17 36
18=cut 37=cut
20package AnyEvent::HTTP; 39package AnyEvent::HTTP;
21 40
22use strict; 41use strict;
23no warnings; 42no warnings;
24 43
25use Carp; 44use Errno ();
26 45
27use AnyEvent (); 46use AnyEvent 5.0 ();
28use AnyEvent::Util (); 47use AnyEvent::Util ();
29use AnyEvent::Socket ();
30use AnyEvent::Handle (); 48use AnyEvent::Handle ();
31 49
32use base Exporter::; 50use base Exporter::;
33 51
34our $VERSION = '1.0'; 52our $VERSION = '1.5';
35 53
36our @EXPORT = qw(http_get http_request); 54our @EXPORT = qw(http_get http_post http_head http_request);
37 55
38our $USERAGENT = "Mozilla/5.0 (compatible; AnyEvent::HTTP/$VERSION; +http://software.schmorp.de/pkg/AnyEvent)"; 56our $USERAGENT = "Mozilla/5.0 (compatible; U; AnyEvent-HTTP/$VERSION; +http://software.schmorp.de/pkg/AnyEvent)";
39our $MAX_RECURSE = 10; 57our $MAX_RECURSE = 10;
40our $MAX_PERSISTENT = 8; 58our $MAX_PERSISTENT = 8;
41our $PERSISTENT_TIMEOUT = 2; 59our $PERSISTENT_TIMEOUT = 2;
42our $TIMEOUT = 300; 60our $TIMEOUT = 300;
43 61
44# changing these is evil 62# changing these is evil
45our $MAX_PERSISTENT_PER_HOST = 2; 63our $MAX_PERSISTENT_PER_HOST = 0;
46our $MAX_PER_HOST = 4; # not respected yet :( 64our $MAX_PER_HOST = 4;
47 65
48our $PROXY; 66our $PROXY;
67our $ACTIVE = 0;
49 68
50my %KA_COUNT; # number of open keep-alive connections per host 69my %KA_COUNT; # number of open keep-alive connections per host
70my %CO_SLOT; # number of open connections, and wait queue, per host
51 71
52=item http_get $url, key => value..., $cb->($data, $headers) 72=item http_get $url, key => value..., $cb->($data, $headers)
53 73
54Executes an HTTP-GET request. See the http_request function for details on 74Executes an HTTP-GET request. See the http_request function for details on
55additional parameters. 75additional parameters and the return value.
56 76
57=item http_head $url, key => value..., $cb->($data, $headers) 77=item http_head $url, key => value..., $cb->($data, $headers)
58 78
59Executes an HTTP-HEAD request. See the http_request function for details on 79Executes an HTTP-HEAD request. See the http_request function for details
60additional parameters. 80on additional parameters and the return value.
61 81
62=item http_post $url, $body, key => value..., $cb->($data, $headers) 82=item http_post $url, $body, key => value..., $cb->($data, $headers)
63 83
64Executes an HTTP-POST request with a request body of C<$bod>. See the 84Executes an HTTP-POST request with a request body of C<$body>. See the
65http_request function for details on additional parameters. 85http_request function for details on additional parameters and the return
86value.
66 87
67=item http_request $method => $url, key => value..., $cb->($data, $headers) 88=item http_request $method => $url, key => value..., $cb->($data, $headers)
68 89
69Executes a HTTP request of type C<$method> (e.g. C<GET>, C<POST>). The URL 90Executes a HTTP request of type C<$method> (e.g. C<GET>, C<POST>). The URL
70must be an absolute http or https URL. 91must be an absolute http or https URL.
71 92
93When called in void context, nothing is returned. In other contexts,
94C<http_request> returns a "cancellation guard" - you have to keep the
95object at least alive until the callback get called. If the object gets
96destroyed before the callback is called, the request will be cancelled.
97
72The callback will be called with the response data as first argument 98The callback will be called with the response body data as first argument
73(or C<undef> if it wasn't available due to errors), and a hash-ref with 99(or C<undef> if an error occured), and a hash-ref with response headers
74response headers as second argument. 100(and trailers) as second argument.
75 101
76All the headers in that hash are lowercased. In addition to the response 102All the headers in that hash are lowercased. In addition to the response
77headers, the three "pseudo-headers" C<HTTPVersion>, C<Status> and 103headers, the "pseudo-headers" (uppercase to avoid clashing with possible
78C<Reason> contain the three parts of the HTTP Status-Line of the same 104response headers) C<HTTPVersion>, C<Status> and C<Reason> contain the
79name. 105three parts of the HTTP Status-Line of the same name. If an error occurs
106during the body phase of a request, then the original C<Status> and
107C<Reason> values from the header are available as C<OrigStatus> and
108C<OrigReason>.
109
110The pseudo-header C<URL> contains the actual URL (which can differ from
111the requested URL when following redirects - for example, you might get
112an error that your URL scheme is not supported even though your URL is a
113valid http URL because it redirected to an ftp URL, in which case you can
114look at the URL pseudo header).
115
116The pseudo-header C<Redirect> only exists when the request was a result
117of an internal redirect. In that case it is an array reference with
118the C<($data, $headers)> from the redirect response. Note that this
119response could in turn be the result of a redirect itself, and C<<
120$headers->{Redirect}[1]{Redirect} >> will then contain the original
121response, and so on.
122
123If the server sends a header multiple times, then their contents will be
124joined together with a comma (C<,>), as per the HTTP spec.
80 125
81If an internal error occurs, such as not being able to resolve a hostname, 126If an internal error occurs, such as not being able to resolve a hostname,
82then C<$data> will be C<undef>, C<< $headers->{Status} >> will be C<599> 127then C<$data> will be C<undef>, C<< $headers->{Status} >> will be C<59x>
83and the C<Reason> pseudo-header will contain an error message. 128(usually C<599>) and the C<Reason> pseudo-header will contain an error
129message.
84 130
85A typical callback might look like this: 131A typical callback might look like this:
86 132
87 sub { 133 sub {
88 my ($body, $hdr) = @_; 134 my ($body, $hdr) = @_;
104Whether to recurse requests or not, e.g. on redirects, authentication 150Whether to recurse requests or not, e.g. on redirects, authentication
105retries and so on, and how often to do so. 151retries and so on, and how often to do so.
106 152
107=item headers => hashref 153=item headers => hashref
108 154
109The request headers to use. 155The request headers to use. Currently, C<http_request> may provide its own
156C<Host:>, C<Content-Length:>, C<Connection:> and C<Cookie:> headers and
157will provide defaults at least for C<TE:>, C<Referer:> and C<User-Agent:>
158(this can be suppressed by using C<undef> for these headers in which case
159they won't be sent at all).
110 160
111=item timeout => $seconds 161=item timeout => $seconds
112 162
113The time-out to use for various stages - each connect attempt will reset 163The time-out to use for various stages - each connect attempt will reset
114the timeout, as will read or write activity. Default timeout is 5 minutes. 164the timeout, as will read or write activity, i.e. this is not an overall
165timeout.
166
167Default timeout is 5 minutes.
115 168
116=item proxy => [$host, $port[, $scheme]] or undef 169=item proxy => [$host, $port[, $scheme]] or undef
117 170
118Use the given http proxy for all requests. If not specified, then the 171Use the given http proxy for all requests. If not specified, then the
119default proxy (as specified by C<$ENV{http_proxy}>) is used. 172default proxy (as specified by C<$ENV{http_proxy}>) is used.
120 173
121C<$scheme> must be either missing or C<http> for HTTP, or C<https> for 174C<$scheme> must be either missing, C<http> for HTTP or C<https> for
122HTTPS. 175HTTPS.
123 176
124=item body => $string 177=item body => $string
125 178
126The request body, usually empty. Will be-sent as-is (future versions of 179The request body, usually empty. Will be sent as-is (future versions of
127this module might offer more options). 180this module might offer more options).
128 181
182=item cookie_jar => $hash_ref
183
184Passing this parameter enables (simplified) cookie-processing, loosely
185based on the original netscape specification.
186
187The C<$hash_ref> must be an (initially empty) hash reference which will
188get updated automatically. It is possible to save the cookie jar to
189persistent storage with something like JSON or Storable, but this is not
190recommended, as session-only cookies might survive longer than expected.
191
192Note that this cookie implementation is not meant to be complete. If
193you want complete cookie management you have to do that on your
194own. C<cookie_jar> is meant as a quick fix to get some cookie-using sites
195working. Cookies are a privacy disaster, do not use them unless required
196to.
197
198When cookie processing is enabled, the C<Cookie:> and C<Set-Cookie:>
199headers will be set and handled by this module, otherwise they will be
200left untouched.
201
202=item tls_ctx => $scheme | $tls_ctx
203
204Specifies the AnyEvent::TLS context to be used for https connections. This
205parameter follows the same rules as the C<tls_ctx> parameter to
206L<AnyEvent::Handle>, but additionally, the two strings C<low> or
207C<high> can be specified, which give you a predefined low-security (no
208verification, highest compatibility) and high-security (CA and common-name
209verification) TLS context.
210
211The default for this option is C<low>, which could be interpreted as "give
212me the page, no matter what".
213
214=item on_prepare => $callback->($fh)
215
216In rare cases you need to "tune" the socket before it is used to
217connect (for exmaple, to bind it on a given IP address). This parameter
218overrides the prepare callback passed to C<AnyEvent::Socket::tcp_connect>
219and behaves exactly the same way (e.g. it has to provide a
220timeout). See the description for the C<$prepare_cb> argument of
221C<AnyEvent::Socket::tcp_connect> for details.
222
223=item tcp_connect => $callback->($host, $service, $connect_cb, $prepare_cb)
224
225In even rarer cases you want total control over how AnyEvent::HTTP
226establishes connections. Normally it uses L<AnyEvent::Socket::tcp_connect>
227to do this, but you can provide your own C<tcp_connect> function -
228obviously, it has to follow the same calling conventions, except that it
229may always return a connection guard object.
230
231There are probably lots of weird uses for this function, starting from
232tracing the hosts C<http_request> actually tries to connect, to (inexact
233but fast) host => IP address caching or even socks protocol support.
234
235=item on_header => $callback->($headers)
236
237When specified, this callback will be called with the header hash as soon
238as headers have been successfully received from the remote server (not on
239locally-generated errors).
240
241It has to return either true (in which case AnyEvent::HTTP will continue),
242or false, in which case AnyEvent::HTTP will cancel the download (and call
243the finish callback with an error code of C<598>).
244
245This callback is useful, among other things, to quickly reject unwanted
246content, which, if it is supposed to be rare, can be faster than first
247doing a C<HEAD> request.
248
249The downside is that cancelling the request makes it impossible to re-use
250the connection. Also, the C<on_header> callback will not receive any
251trailer (headers sent after the response body).
252
253Example: cancel the request unless the content-type is "text/html".
254
255 on_header => sub {
256 $_[0]{"content-type"} =~ /^text\/html\s*(?:;|$)/
257 },
258
259=item on_body => $callback->($partial_body, $headers)
260
261When specified, all body data will be passed to this callback instead of
262to the completion callback. The completion callback will get the empty
263string instead of the body data.
264
265It has to return either true (in which case AnyEvent::HTTP will continue),
266or false, in which case AnyEvent::HTTP will cancel the download (and call
267the completion callback with an error code of C<598>).
268
269The downside to cancelling the request is that it makes it impossible to
270re-use the connection.
271
272This callback is useful when the data is too large to be held in memory
273(so the callback writes it to a file) or when only some information should
274be extracted, or when the body should be processed incrementally.
275
276It is usually preferred over doing your own body handling via
277C<want_body_handle>, but in case of streaming APIs, where HTTP is
278only used to create a connection, C<want_body_handle> is the better
279alternative, as it allows you to install your own event handler, reducing
280resource usage.
281
282=item want_body_handle => $enable
283
284When enabled (default is disabled), the behaviour of AnyEvent::HTTP
285changes considerably: after parsing the headers, and instead of
286downloading the body (if any), the completion callback will be
287called. Instead of the C<$body> argument containing the body data, the
288callback will receive the L<AnyEvent::Handle> object associated with the
289connection. In error cases, C<undef> will be passed. When there is no body
290(e.g. status C<304>), the empty string will be passed.
291
292The handle object might or might not be in TLS mode, might be connected to
293a proxy, be a persistent connection etc., and configured in unspecified
294ways. The user is responsible for this handle (it will not be used by this
295module anymore).
296
297This is useful with some push-type services, where, after the initial
298headers, an interactive protocol is used (typical example would be the
299push-style twitter API which starts a JSON/XML stream).
300
301If you think you need this, first have a look at C<on_body>, to see if
302that doesn't solve your problem in a better way.
303
129=back 304=back
130 305
131=back 306Example: do a simple HTTP GET request for http://www.nethype.de/ and print
307the response body.
308
309 http_request GET => "http://www.nethype.de/", sub {
310 my ($body, $hdr) = @_;
311 print "$body\n";
312 };
313
314Example: do a HTTP HEAD request on https://www.google.com/, use a
315timeout of 30 seconds.
316
317 http_request
318 GET => "https://www.google.com",
319 timeout => 30,
320 sub {
321 my ($body, $hdr) = @_;
322 use Data::Dumper;
323 print Dumper $hdr;
324 }
325 ;
326
327Example: do another simple HTTP GET request, but immediately try to
328cancel it.
329
330 my $request = http_request GET => "http://www.nethype.de/", sub {
331 my ($body, $hdr) = @_;
332 print "$body\n";
333 };
334
335 undef $request;
132 336
133=cut 337=cut
134 338
339sub _slot_schedule;
340sub _slot_schedule($) {
341 my $host = shift;
342
343 while ($CO_SLOT{$host}[0] < $MAX_PER_HOST) {
344 if (my $cb = shift @{ $CO_SLOT{$host}[1] }) {
345 # somebody wants that slot
346 ++$CO_SLOT{$host}[0];
347 ++$ACTIVE;
348
349 $cb->(AnyEvent::Util::guard {
350 --$ACTIVE;
351 --$CO_SLOT{$host}[0];
352 _slot_schedule $host;
353 });
354 } else {
355 # nobody wants the slot, maybe we can forget about it
356 delete $CO_SLOT{$host} unless $CO_SLOT{$host}[0];
357 last;
358 }
359 }
360}
361
362# wait for a free slot on host, call callback
363sub _get_slot($$) {
364 push @{ $CO_SLOT{$_[0]}[1] }, $_[1];
365
366 _slot_schedule $_[0];
367}
368
369# continue to parse $_ for headers and place them into the arg
370sub parse_hdr() {
371 my %hdr;
372
373 # things seen, not parsed:
374 # p3pP="NON CUR OTPi OUR NOR UNI"
375
376 $hdr{lc $1} .= ",$2"
377 while /\G
378 ([^:\000-\037]*):
379 [\011\040]*
380 ((?: [^\012]+ | \012[\011\040] )*)
381 \012
382 /gxc;
383
384 /\G$/
385 or return;
386
387 # remove the "," prefix we added to all headers above
388 substr $_, 0, 1, ""
389 for values %hdr;
390
391 \%hdr
392}
393
394our $qr_nlnl = qr{(?<![^\012])\015?\012};
395
396our $TLS_CTX_LOW = { cache => 1, sslv2 => 1 };
397our $TLS_CTX_HIGH = { cache => 1, verify => 1, verify_peername => "https" };
398
135sub http_request($$$;@) { 399sub http_request($$@) {
136 my $cb = pop; 400 my $cb = pop;
137 my ($method, $url, %arg) = @_; 401 my ($method, $url, %arg) = @_;
138 402
139 my %hdr; 403 my %hdr;
404
405 $arg{tls_ctx} = $TLS_CTX_LOW if $arg{tls_ctx} eq "low" || !exists $arg{tls_ctx};
406 $arg{tls_ctx} = $TLS_CTX_HIGH if $arg{tls_ctx} eq "high";
140 407
141 $method = uc $method; 408 $method = uc $method;
142 409
143 if (my $hdr = $arg{headers}) { 410 if (my $hdr = $arg{headers}) {
144 while (my ($k, $v) = each %$hdr) { 411 while (my ($k, $v) = each %$hdr) {
145 $hdr{lc $k} = $v; 412 $hdr{lc $k} = $v;
146 } 413 }
147 } 414 }
148 415
416 # pseudo headers for all subsequent responses
417 my @pseudo = (URL => $url);
418 push @pseudo, Redirect => delete $arg{Redirect} if exists $arg{Redirect};
419
149 my $recurse = exists $arg{recurse} ? $arg{recurse} : $MAX_RECURSE; 420 my $recurse = exists $arg{recurse} ? delete $arg{recurse} : $MAX_RECURSE;
150 421
151 return $cb->(undef, { Status => 599, Reason => "recursion limit reached" }) 422 return $cb->(undef, { @pseudo, Status => 599, Reason => "Too many redirections" })
152 if $recurse < 0; 423 if $recurse < 0;
153 424
154 my $proxy = $arg{proxy} || $PROXY; 425 my $proxy = $arg{proxy} || $PROXY;
155 my $timeout = $arg{timeout} || $TIMEOUT; 426 my $timeout = $arg{timeout} || $TIMEOUT;
156 427
157 $hdr{"user-agent"} ||= $USERAGENT; 428 my ($uscheme, $uauthority, $upath, $query, $fragment) =
429 $url =~ m|(?:([^:/?#]+):)?(?://([^/?#]*))?([^?#]*)(?:(\?[^#]*))?(?:#(.*))?|;
158 430
159 my ($host, $port, $path, $scheme); 431 $uscheme = lc $uscheme;
432
433 my $uport = $uscheme eq "http" ? 80
434 : $uscheme eq "https" ? 443
435 : return $cb->(undef, { @pseudo, Status => 599, Reason => "Only http and https URL schemes supported" });
436
437 $uauthority =~ /^(?: .*\@ )? ([^\@:]+) (?: : (\d+) )?$/x
438 or return $cb->(undef, { @pseudo, Status => 599, Reason => "Unparsable URL" });
439
440 my $uhost = $1;
441 $uport = $2 if defined $2;
442
443 $hdr{host} = defined $2 ? "$uhost:$2" : "$uhost"
444 unless exists $hdr{host};
445
446 $uhost =~ s/^\[(.*)\]$/$1/;
447 $upath .= $query if length $query;
448
449 $upath =~ s%^/?%/%;
450
451 # cookie processing
452 if (my $jar = $arg{cookie_jar}) {
453 %$jar = () if $jar->{version} != 1;
454
455 my @cookie;
456
457 while (my ($chost, $paths) = each %$jar) {
458 if ($chost =~ /^\./) {
459 next unless $chost eq substr $uhost, -length $chost;
460 } elsif ($chost =~ /\./) {
461 next unless $chost eq $uhost;
462 } else {
463 next;
464 }
465
466 while (my ($cpath, $cookies) = each %$paths) {
467 next unless $cpath eq substr $upath, 0, length $cpath;
468
469 while (my ($cookie, $kv) = each %$cookies) {
470 next if $uscheme ne "https" && exists $kv->{secure};
471
472 if (exists $kv->{expires}) {
473 if (AE::now > parse_date ($kv->{expires})) {
474 delete $cookies->{$cookie};
475 next;
476 }
477 }
478
479 my $value = $kv->{value};
480 $value =~ s/([\\"])/\\$1/g;
481 push @cookie, "$cookie=\"$value\"";
482 }
483 }
484 }
485
486 $hdr{cookie} = join "; ", @cookie
487 if @cookie;
488 }
489
490 my ($rhost, $rport, $rscheme, $rpath); # request host, port, path
160 491
161 if ($proxy) { 492 if ($proxy) {
162 ($host, $port, $scheme) = @$proxy; 493 ($rpath, $rhost, $rport, $rscheme) = ($url, @$proxy);
163 $path = $url; 494
495 $rscheme = "http" unless defined $rscheme;
496
497 # don't support https requests over https-proxy transport,
498 # can't be done with tls as spec'ed, unless you double-encrypt.
499 $rscheme = "http" if $uscheme eq "https" && $rscheme eq "https";
164 } else { 500 } else {
165 ($scheme, my $authority, $path, my $query, my $fragment) = 501 ($rhost, $rport, $rscheme, $rpath) = ($uhost, $uport, $uscheme, $upath);
166 $url =~ m|(?:([^:/?#]+):)?(?://([^/?#]*))?([^?#]*)(?:\?([^#]*))?(?:#(.*))?|;
167
168 $port = $scheme eq "http" ? 80
169 : $scheme eq "https" ? 443
170 : return $cb->(undef, { Status => 599, Reason => "$url: only http and https URLs supported" });
171
172 $authority =~ /^(?: .*\@ )? ([^\@:]+) (?: : (\d+) )?$/x
173 or return $cb->(undef, { Status => 599, Reason => "$url: unparsable URL" });
174
175 $host = $1;
176 $port = $2 if defined $2;
177
178 $host =~ s/^\[(.*)\]$/$1/;
179 $path .= "?$query" if length $query;
180
181 $path = "/" unless $path;
182
183 $hdr{host} = $host = lc $host;
184 } 502 }
185 503
186 $scheme = lc $scheme; 504 # leave out fragment and query string, just a heuristic
505 $hdr{referer} = "$uscheme://$uauthority$upath" unless exists $hdr{referer};
506 $hdr{"user-agent"} = $USERAGENT unless exists $hdr{"user-agent"};
187 507
188 my %state;
189
190 $hdr{"content-length"} = length $arg{body}; 508 $hdr{"content-length"} = length $arg{body}
509 if length $arg{body} || $method ne "GET";
191 510
192 $state{connect_guard} = AnyEvent::Socket::tcp_connect $host, $port, sub { 511 $hdr{connection} = "close TE"; #1.1
512 $hdr{te} = "trailers" unless exists $hdr{te}; #1.1
513
514 my %state = (connect_guard => 1);
515
516 _get_slot $uhost, sub {
517 $state{slot_guard} = shift;
518
519 return unless $state{connect_guard};
520
521 my $connect_cb = sub {
193 $state{fh} = shift 522 $state{fh} = shift
523 or do {
524 my $err = "$!";
525 %state = ();
194 or return $cb->(undef, { Status => 599, Reason => "$!" }); 526 return $cb->(undef, { @pseudo, Status => 599, Reason => $err });
527 };
195 528
196 delete $state{connect_guard}; # reduce memory usage, save a tree 529 pop; # free memory, save a tree
197 530
531 return unless delete $state{connect_guard};
532
198 # get handle 533 # get handle
199 $state{handle} = new AnyEvent::Handle 534 $state{handle} = new AnyEvent::Handle
200 fh => $state{fh}, 535 fh => $state{fh},
201 ($scheme eq "https" ? (tls => "connect") : ()); 536 peername => $rhost,
537 tls_ctx => $arg{tls_ctx},
538 # these need to be reconfigured on keepalive handles
539 timeout => $timeout,
540 on_error => sub {
541 %state = ();
542 $cb->(undef, { @pseudo, Status => 599, Reason => $_[2] });
543 },
544 on_eof => sub {
545 %state = ();
546 $cb->(undef, { @pseudo, Status => 599, Reason => "Unexpected end-of-file" });
547 },
548 ;
202 549
203 # limit the number of persistent connections 550 # limit the number of persistent connections
551 # keepalive not yet supported
204 if ($KA_COUNT{$_[1]} < $MAX_PERSISTENT_PER_HOST) { 552# if ($KA_COUNT{$_[1]} < $MAX_PERSISTENT_PER_HOST) {
205 ++$KA_COUNT{$_[1]}; 553# ++$KA_COUNT{$_[1]};
206 $state{handle}{ka_count_guard} = AnyEvent::Util::guard { --$KA_COUNT{$_[1]} }; 554# $state{handle}{ka_count_guard} = AnyEvent::Util::guard {
555# --$KA_COUNT{$_[1]}
556# };
207 $hdr{connection} = "keep-alive"; 557# $hdr{connection} = "keep-alive";
208 delete $hdr{connection}; # keep-alive not yet supported
209 } else {
210 delete $hdr{connection};
211 } 558# }
212 559
213 # (re-)configure handle 560 $state{handle}->starttls ("connect") if $rscheme eq "https";
214 $state{handle}->timeout ($timeout);
215 $state{handle}->on_error (sub {
216 %state = ();
217 $cb->(undef, { Status => 599, Reason => "$!" });
218 });
219 $state{handle}->on_eof (sub {
220 %state = ();
221 $cb->(undef, { Status => 599, Reason => "unexpected end-of-file" });
222 });
223 561
562 # handle actual, non-tunneled, request
563 my $handle_actual_request = sub {
564 $state{handle}->starttls ("connect") if $uscheme eq "https" && !exists $state{handle}{tls};
565
224 # send request 566 # send request
225 $state{handle}->push_write ( 567 $state{handle}->push_write (
226 "$method $path HTTP/1.0\015\012" 568 "$method $rpath HTTP/1.1\015\012"
227 . (join "", map "$_: $hdr{$_}\015\012", keys %hdr) 569 . (join "", map "\u$_: $hdr{$_}\015\012", grep defined $hdr{$_}, keys %hdr)
228 . "\015\012" 570 . "\015\012"
229 . (delete $arg{body}) 571 . (delete $arg{body})
230 );
231
232 %hdr = (); # reduce memory usage, save a kitten
233
234 # status line
235 $state{handle}->push_read (line => qr/\015?\012/, sub {
236 $_[1] =~ /^HTTP\/([0-9\.]+) \s+ ([0-9]{3}) \s+ ([^\015\012]+)/ix
237 or return (%state = (), $cb->(undef, { Status => 599, Reason => "invalid server response ($_[1])" }));
238
239 my %hdr = ( # response headers
240 HTTPVersion => ",$1",
241 Status => ",$2",
242 Reason => ",$3",
243 ); 572 );
244 573
245 # headers, could be optimized a bit 574 # return if error occured during push_write()
246 $state{handle}->unshift_read (line => qr/\015?\012\015?\012/, sub { 575 return unless %state;
576
577 %hdr = (); # reduce memory usage, save a kitten, also make it possible to re-use
578
579 # status line and headers
580 $state{read_response} = sub {
247 for ("$_[1]\012") { 581 for ("$_[1]") {
248 # we support spaces in field names, as lotus domino 582 y/\015//d; # weed out any \015, as they show up in the weirdest of places.
249 # creates them. 583
250 $hdr{lc $1} .= ",$2" 584 /^HTTP\/([0-9\.]+) \s+ ([0-9]{3}) (?: \s+ ([^\012]*) )? \012/igxc
251 while /\G 585 or return (%state = (), $cb->(undef, { @pseudo, Status => 599, Reason => "Invalid server response" }));
252 ([^:\000-\037]+): 586
253 [\011\040]* 587 # 100 Continue handling
254 ((?: [^\015\012]+ | \015?\012[\011\040] )*) 588 # should not happen as we don't send expect: 100-continue,
255 \015?\012 589 # but we handle it just in case.
590 # since we send the request body regardless, if we get an error
591 # we are out of-sync, which we currently do NOT handle correctly.
592 return $state{handle}->push_read (line => $qr_nlnl, $state{read_response})
593 if $2 eq 100;
594
595 push @pseudo,
596 HTTPVersion => $1,
597 Status => $2,
598 Reason => $3,
256 /gxc; 599 ;
257 600
258 /\G$/ 601 my $hdr = parse_hdr
259 or return $cb->(undef, { Status => 599, Reason => "garbled response headers" }); 602 or return (%state = (), $cb->(undef, { @pseudo, Status => 599, Reason => "Garbled response headers" }));
603
604 %hdr = (%$hdr, @pseudo);
260 } 605 }
261 606
262 substr $_, 0, 1, "" 607 # redirect handling
263 for values %hdr; 608 # microsoft and other shitheads don't give a shit for following standards,
609 # try to support some common forms of broken Location headers.
610 if ($hdr{location} !~ /^(?: $ | [^:\/?\#]+ : )/x) {
611 $hdr{location} =~ s/^\.\/+//;
264 612
265 my $finish = sub { 613 my $url = "$rscheme://$uhost:$uport";
266 if ($_[1]{Status} =~ /^30[12]$/ && $recurse) { 614
267 http_request ($method, $_[1]{location}, %arg, recurse => $recurse - 1, $cb); 615 unless ($hdr{location} =~ s/^\///) {
616 $url .= $upath;
617 $url =~ s/\/[^\/]*$//;
618 }
619
620 $hdr{location} = "$url/$hdr{location}";
621 }
622
623 my $redirect;
624
625 if ($recurse) {
626 my $status = $hdr{Status};
627
628 # industry standard is to redirect POST as GET for
629 # 301, 302 and 303, in contrast to http/1.0 and 1.1.
630 # also, the UA should ask the user for 301 and 307 and POST,
631 # industry standard seems to be to simply follow.
632 # we go with the industry standard.
633 if ($status == 301 or $status == 302 or $status == 303) {
634 # HTTP/1.1 is unclear on how to mutate the method
635 $method = "GET" unless $method eq "HEAD";
636 $redirect = 1;
637 } elsif ($status == 307) {
638 $redirect = 1;
639 }
640 }
641
642 my $finish = sub { # ($data, $err_status, $err_reason[, $keepalive])
643 my $keepalive = pop;
644
645 $state{handle}->destroy if $state{handle};
646 %state = ();
647
648 if (defined $_[1]) {
649 $hdr{OrigStatus} = $hdr{Status}; $hdr{Status} = $_[1];
650 $hdr{OrigReason} = $hdr{Reason}; $hdr{Reason} = $_[2];
651 }
652
653 # set-cookie processing
654 if ($arg{cookie_jar}) {
655 for ($hdr{"set-cookie"}) {
656 # parse NAME=VALUE
657 my @kv;
658
659 while (
660 m{
661 \G\s*
662 (?:
663 expires \s*=\s* ([A-Z][a-z][a-z],\ [^,;]+)
664 | ([^=;,[:space:]]+) \s*=\s* (?: "((?:[^\\"]+|\\.)*)" | ([^=;,[:space:]]*) )
665 )
666 }gcxsi
667 ) {
668 my $name = $2;
669 my $value = $4;
670
671 unless (defined $name) {
672 # expires
673 $name = "expires";
674 $value = $1;
675 } elsif (!defined $value) {
676 # quoted
677 $value = $3;
678 $value =~ s/\\(.)/$1/gs;
679 }
680
681 push @kv, lc $name, $value;
682
683 last unless /\G\s*;/gc;
684 }
685
686 last unless @kv;
687
688 my $name = shift @kv;
689 my %kv = (value => shift @kv, @kv);
690
691 $kv{expires} ||= format_date (AE::now + $kv{"max-age"})
692 if exists $kv{"max-age"};
693
694 my $cdom;
695 my $cpath = (delete $kv{path}) || "/";
696
697 if (exists $kv{domain}) {
698 $cdom = delete $kv{domain};
699
700 $cdom =~ s/^\.?/./; # make sure it starts with a "."
701
702 next if $cdom =~ /\.$/;
703
704 # this is not rfc-like and not netscape-like. go figure.
705 my $ndots = $cdom =~ y/.//;
706 next if $ndots < ($cdom =~ /\.[^.][^.]\.[^.][^.]$/ ? 3 : 2);
707 } else {
708 $cdom = $uhost;
709 }
710
711 # store it
712 $arg{cookie_jar}{version} = 1;
713 $arg{cookie_jar}{$cdom}{$cpath}{$name} = \%kv;
714
715 redo if /\G\s*,/gc;
716 }
717 }
718
719 if ($redirect && exists $hdr{location}) {
720 # we ignore any errors, as it is very common to receive
721 # Content-Length != 0 but no actual body
722 # we also access %hdr, as $_[1] might be an erro
723 http_request (
724 $method => $hdr{location},
725 %arg,
726 recurse => $recurse - 1,
727 Redirect => [$_[0], \%hdr],
728 $cb);
729 } else {
730 $cb->($_[0], \%hdr);
731 }
732 };
733
734 my $len = $hdr{"content-length"};
735
736 if (!$redirect && $arg{on_header} && !$arg{on_header}(\%hdr)) {
737 $finish->(undef, 598 => "Request cancelled by on_header");
738 } elsif (
739 $hdr{Status} =~ /^(?:1..|204|205|304)$/
740 or $method eq "HEAD"
741 or (defined $len && !$len)
742 ) {
743 # no body
744 $finish->("", undef, undef, 1);
268 } else { 745 } else {
269 $cb->($_[0], $_[1]); 746 # body handling, many different code paths
747 # - no body expected
748 # - want_body_handle
749 # - te chunked
750 # - 2x length known (with or without on_body)
751 # - 2x length not known (with or without on_body)
752 if (!$redirect && $arg{want_body_handle}) {
753 $_[0]->on_eof (undef);
754 $_[0]->on_error (undef);
755 $_[0]->on_read (undef);
756
757 $finish->(delete $state{handle});
758
759 } elsif ($hdr{"transfer-encoding"} =~ /\bchunked\b/i) {
760 my $cl = 0;
761 my $body = undef;
762 my $on_body = $arg{on_body} || sub { $body .= shift; 1 };
763
764 $_[0]->on_error (sub { $finish->(undef, 599 => $_[2]) });
765
766 my $read_chunk; $read_chunk = sub {
767 $_[1] =~ /^([0-9a-fA-F]+)/
768 or $finish->(undef, 599 => "Garbled chunked transfer encoding");
769
770 my $len = hex $1;
771
772 if ($len) {
773 $cl += $len;
774
775 $_[0]->push_read (chunk => $len, sub {
776 $on_body->($_[1], \%hdr)
777 or return $finish->(undef, 598 => "Request cancelled by on_body");
778
779 $_[0]->push_read (line => sub {
780 length $_[1]
781 and return $finish->(undef, 599 => "Garbled chunked transfer encoding");
782 $_[0]->push_read (line => $read_chunk);
783 });
784 });
785 } else {
786 $hdr{"content-length"} ||= $cl;
787
788 $_[0]->push_read (line => $qr_nlnl, sub {
789 if (length $_[1]) {
790 for ("$_[1]") {
791 y/\015//d; # weed out any \015, as they show up in the weirdest of places.
792
793 my $hdr = parse_hdr
794 or return $finish->(undef, 599 => "Garbled response trailers");
795
796 %hdr = (%hdr, %$hdr);
797 }
798 }
799
800 $finish->($body, undef, undef, 1);
801 });
802 }
803 };
804
805 $_[0]->push_read (line => $read_chunk);
806
807 } elsif ($arg{on_body}) {
808 $_[0]->on_error (sub { $finish->(undef, 599 => $_[2]) });
809
810 if ($len) {
811 $_[0]->on_read (sub {
812 $len -= length $_[0]{rbuf};
813
814 $arg{on_body}(delete $_[0]{rbuf}, \%hdr)
815 or return $finish->(undef, 598 => "Request cancelled by on_body");
816
817 $len > 0
818 or $finish->("", undef, undef, 1);
819 });
820 } else {
821 $_[0]->on_eof (sub {
822 $finish->("");
823 });
824 $_[0]->on_read (sub {
825 $arg{on_body}(delete $_[0]{rbuf}, \%hdr)
826 or $finish->(undef, 598 => "Request cancelled by on_body");
827 });
828 }
829 } else {
830 $_[0]->on_eof (undef);
831
832 if ($len) {
833 $_[0]->on_error (sub { $finish->(undef, 599 => $_[2]) });
834 $_[0]->on_read (sub {
835 $finish->((substr delete $_[0]{rbuf}, 0, $len, ""), undef, undef, 1)
836 if $len <= length $_[0]{rbuf};
837 });
838 } else {
839 $_[0]->on_error (sub {
840 ($! == Errno::EPIPE || !$!)
841 ? $finish->(delete $_[0]{rbuf})
842 : $finish->(undef, 599 => $_[2]);
843 });
844 $_[0]->on_read (sub { });
845 }
846 }
270 } 847 }
271 }; 848 };
272 849
273 if ($hdr{Status} =~ /^(?:1..|204|304)$/ or $method eq "HEAD") { 850 $state{handle}->push_read (line => $qr_nlnl, $state{read_response});
274 %state = (); 851 };
275 $finish->(undef, \%hdr);
276 } else {
277 if (exists $hdr{"content-length"}) {
278 $_[0]->unshift_read (chunk => $hdr{"content-length"}, sub {
279 # could cache persistent connection now
280 if ($hdr{connection} =~ /\bkeep-alive\b/i) {
281 # but we don't, due to misdesigns, this is annoyingly complex
282 };
283 852
284 %state = (); 853 # now handle proxy-CONNECT method
285 $finish->($_[1], \%hdr); 854 if ($proxy && $uscheme eq "https") {
286 }); 855 # oh dear, we have to wrap it into a connect request
856
857 # maybe re-use $uauthority with patched port?
858 $state{handle}->push_write ("CONNECT $uhost:$uport HTTP/1.0\015\012Host: $uhost\015\012\015\012");
859 $state{handle}->push_read (line => $qr_nlnl, sub {
860 $_[1] =~ /^HTTP\/([0-9\.]+) \s+ ([0-9]{3}) (?: \s+ ([^\015\012]*) )?/ix
861 or return (%state = (), $cb->(undef, { @pseudo, Status => 599, Reason => "Invalid proxy connect response ($_[1])" }));
862
863 if ($2 == 200) {
864 $rpath = $upath;
865 &$handle_actual_request;
287 } else { 866 } else {
288 # too bad, need to read until we get an error or EOF,
289 # no way to detect winged data.
290 $_[0]->on_error (sub {
291 %state = (); 867 %state = ();
292 $finish->($_[0]{rbuf}, \%hdr); 868 $cb->(undef, { @pseudo, Status => $2, Reason => $3 });
293 });
294 $_[0]->on_eof (undef);
295 $_[0]->on_read (sub { });
296 } 869 }
297 } 870 });
871 } else {
872 &$handle_actual_request;
298 }); 873 }
299 }); 874 };
300 }, sub { 875
301 $timeout 876 my $tcp_connect = $arg{tcp_connect}
877 || do { require AnyEvent::Socket; \&AnyEvent::Socket::tcp_connect };
878
879 $state{connect_guard} = $tcp_connect->($rhost, $rport, $connect_cb, $arg{on_prepare} || sub { $timeout });
880
302 }; 881 };
303 882
304 defined wantarray && AnyEvent::Util::guard { %state = () } 883 defined wantarray && AnyEvent::Util::guard { %state = () }
305} 884}
306 885
307sub http_get($$;@) { 886sub http_get($@) {
308 unshift @_, "GET"; 887 unshift @_, "GET";
309 &http_request 888 &http_request
310} 889}
311 890
312sub http_head($$;@) { 891sub http_head($@) {
313 unshift @_, "HEAD"; 892 unshift @_, "HEAD";
314 &http_request 893 &http_request
315} 894}
316 895
317sub http_post($$$;@) { 896sub http_post($$@) {
897 my $url = shift;
318 unshift @_, "POST", "body"; 898 unshift @_, "POST", $url, "body";
319 &http_request 899 &http_request
320} 900}
321 901
902=back
903
904=head2 DNS CACHING
905
906AnyEvent::HTTP uses the AnyEvent::Socket::tcp_connect function for
907the actual connection, which in turn uses AnyEvent::DNS to resolve
908hostnames. The latter is a simple stub resolver and does no caching
909on its own. If you want DNS caching, you currently have to provide
910your own default resolver (by storing a suitable resolver object in
911C<$AnyEvent::DNS::RESOLVER>).
912
322=head2 GLOBAL FUNCTIONS AND VARIABLES 913=head2 GLOBAL FUNCTIONS AND VARIABLES
323 914
324=over 4 915=over 4
325 916
326=item AnyEvent::HTTP::set_proxy "proxy-url" 917=item AnyEvent::HTTP::set_proxy "proxy-url"
327 918
328Sets the default proxy server to use. The proxy-url must begin with a 919Sets the default proxy server to use. The proxy-url must begin with a
329string of the form C<http://host:port> (optionally C<https:...>). 920string of the form C<http://host:port> (optionally C<https:...>), croaks
921otherwise.
922
923To clear an already-set proxy, use C<undef>.
924
925=item $date = AnyEvent::HTTP::format_date $timestamp
926
927Takes a POSIX timestamp (seconds since the epoch) and formats it as a HTTP
928Date (RFC 2616).
929
930=item $timestamp = AnyEvent::HTTP::parse_date $date
931
932Takes a HTTP Date (RFC 2616) or a Cookie date (netscape cookie spec) and
933returns the corresponding POSIX timestamp, or C<undef> if the date cannot
934be parsed.
330 935
331=item $AnyEvent::HTTP::MAX_RECURSE 936=item $AnyEvent::HTTP::MAX_RECURSE
332 937
333The default value for the C<recurse> request parameter (default: C<10>). 938The default value for the C<recurse> request parameter (default: C<10>).
334 939
335=item $AnyEvent::HTTP::USERAGENT 940=item $AnyEvent::HTTP::USERAGENT
336 941
337The default value for the C<User-Agent> header (the default is 942The default value for the C<User-Agent> header (the default is
338C<Mozilla/5.0 (compatible; AnyEvent::HTTP/$VERSION; +http://software.schmorp.de/pkg/AnyEvent)>). 943C<Mozilla/5.0 (compatible; U; AnyEvent-HTTP/$VERSION; +http://software.schmorp.de/pkg/AnyEvent)>).
339 944
340=item $AnyEvent::HTTP::MAX_PERSISTENT 945=item $AnyEvent::HTTP::MAX_PER_HOST
341 946
342The maximum number of persistent connections to keep open (default: 8). 947The maximum number of concurrent connections to the same host (identified
948by the hostname). If the limit is exceeded, then the additional requests
949are queued until previous connections are closed.
343 950
344Not implemented currently. 951The default value for this is C<4>, and it is highly advisable to not
952increase it.
345 953
346=item $AnyEvent::HTTP::PERSISTENT_TIMEOUT 954=item $AnyEvent::HTTP::ACTIVE
347 955
348The maximum time to cache a persistent connection, in seconds (default: 2). 956The number of active connections. This is not the number of currently
349 957running requests, but the number of currently open and non-idle TCP
350Not implemented currently. 958connections. This number of can be useful for load-leveling.
351 959
352=back 960=back
353 961
354=cut 962=cut
355 963
964our @month = qw(Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec);
965our @weekday = qw(Sun Mon Tue Wed Thu Fri Sat);
966
967sub format_date($) {
968 my ($time) = @_;
969
970 # RFC 822/1123 format
971 my ($S, $M, $H, $mday, $mon, $year, $wday, $yday, undef) = gmtime $time;
972
973 sprintf "%s, %02d %s %04d %02d:%02d:%02d GMT",
974 $weekday[$wday], $mday, $month[$mon], $year + 1900,
975 $H, $M, $S;
976}
977
978sub parse_date($) {
979 my ($date) = @_;
980
981 my ($d, $m, $y, $H, $M, $S);
982
983 if ($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$/) {
984 # RFC 822/1123, required by RFC 2616 (with " ")
985 # cookie dates (with "-")
986
987 ($d, $m, $y, $H, $M, $S) = ($1, $2, $3, $4, $5, $6);
988
989 } elsif ($date =~ /^[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$/) {
990 # RFC 850
991 ($d, $m, $y, $H, $M, $S) = ($1, $2, $3 < 69 ? $3 + 2000 : $3 + 1900, $4, $5, $6);
992
993 } elsif ($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])$/) {
994 # ISO C's asctime
995 ($d, $m, $y, $H, $M, $S) = ($2, $1, $6, $3, $4, $5);
996 }
997 # other formats fail in the loop below
998
999 for (0..11) {
1000 if ($m eq $month[$_]) {
1001 require Time::Local;
1002 return Time::Local::timegm ($S, $M, $H, $d, $_, $y);
1003 }
1004 }
1005
1006 undef
1007}
1008
356sub set_proxy($) { 1009sub set_proxy($) {
1010 if (length $_[0]) {
357 $PROXY = [$2, $3 || 3128, $1] if $_[0] =~ m%^(https?):// ([^:/]+) (?: : (\d*) )?%ix; 1011 $_[0] =~ m%^(https?):// ([^:/]+) (?: : (\d*) )?%ix
1012 or Carp::croak "$_[0]: invalid proxy URL";
1013 $PROXY = [$2, $3 || 3128, $1]
1014 } else {
1015 undef $PROXY;
1016 }
358} 1017}
359 1018
360# initialise proxy from environment 1019# initialise proxy from environment
1020eval {
361set_proxy $ENV{http_proxy}; 1021 set_proxy $ENV{http_proxy};
1022};
1023
1024=head2 SOCKS PROXIES
1025
1026Socks proxies are not directly supported by AnyEvent::HTTP. You can
1027compile your perl to support socks, or use an external program such as
1028F<socksify> (dante) or F<tsocks> to make your program use a socks proxy
1029transparently.
1030
1031Alternatively, for AnyEvent::HTTP only, you can use your own
1032C<tcp_connect> function that does the proxy handshake - here is an example
1033that works with socks4a proxies:
1034
1035 use Errno;
1036 use AnyEvent::Util;
1037 use AnyEvent::Socket;
1038 use AnyEvent::Handle;
1039
1040 # host, port and username of/for your socks4a proxy
1041 my $socks_host = "10.0.0.23";
1042 my $socks_port = 9050;
1043 my $socks_user = "";
1044
1045 sub socks4a_connect {
1046 my ($host, $port, $connect_cb, $prepare_cb) = @_;
1047
1048 my $hdl = new AnyEvent::Handle
1049 connect => [$socks_host, $socks_port],
1050 on_prepare => sub { $prepare_cb->($_[0]{fh}) },
1051 on_error => sub { $connect_cb->() },
1052 ;
1053
1054 $hdl->push_write (pack "CCnNZ*Z*", 4, 1, $port, 1, $socks_user, $host);
1055
1056 $hdl->push_read (chunk => 8, sub {
1057 my ($hdl, $chunk) = @_;
1058 my ($status, $port, $ipn) = unpack "xCna4", $chunk;
1059
1060 if ($status == 0x5a) {
1061 $connect_cb->($hdl->{fh}, (format_address $ipn) . ":$port");
1062 } else {
1063 $! = Errno::ENXIO; $connect_cb->();
1064 }
1065 });
1066
1067 $hdl
1068 }
1069
1070Use C<socks4a_connect> instead of C<tcp_connect> when doing C<http_request>s,
1071possibly after switching off other proxy types:
1072
1073 AnyEvent::HTTP::set_proxy undef; # usually you do not want other proxies
1074
1075 http_get 'http://www.google.com', tcp_connect => \&socks4a_connect, sub {
1076 my ($data, $headers) = @_;
1077 ...
1078 };
362 1079
363=head1 SEE ALSO 1080=head1 SEE ALSO
364 1081
365L<AnyEvent>. 1082L<AnyEvent>.
366 1083
367=head1 AUTHOR 1084=head1 AUTHOR
368 1085
369 Marc Lehmann <schmorp@schmorp.de> 1086 Marc Lehmann <schmorp@schmorp.de>
370 http://home.schmorp.de/ 1087 http://home.schmorp.de/
1088
1089With many thanks to Дмитрий Шалашов, who provided countless
1090testcases and bugreports.
371 1091
372=cut 1092=cut
373 1093
3741 10941
375 1095

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