| 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 |
=head1 DESCRIPTION |
| 10 |
|
| 11 |
This module is an L<AnyEvent> user, you need to make sure that you use and |
| 12 |
run a supported event loop. |
| 13 |
|
| 14 |
This module implements a simple, stateless and non-blocking HTTP |
| 15 |
client. It supports GET, POST and other request methods, cookies and more, |
| 16 |
all on a very low level. It can follow redirects supports proxies and |
| 17 |
automatically limits the number of connections to the values specified in |
| 18 |
the RFC. |
| 19 |
|
| 20 |
It should generally be a "good client" that is enough for most HTTP |
| 21 |
tasks. Simple tasks should be simple, but complex tasks should still be |
| 22 |
possible as the user retains control over request and response headers. |
| 23 |
|
| 24 |
The caller is responsible for authentication management, cookies (if |
| 25 |
the simplistic implementation in this module doesn't suffice), referer |
| 26 |
and other high-level protocol details for which this module offers only |
| 27 |
limited support. |
| 28 |
|
| 29 |
=head2 METHODS |
| 30 |
|
| 31 |
=over 4 |
| 32 |
|
| 33 |
=cut |
| 34 |
|
| 35 |
package AnyEvent::HTTP; |
| 36 |
|
| 37 |
use strict; |
| 38 |
no warnings; |
| 39 |
|
| 40 |
use Carp; |
| 41 |
|
| 42 |
use AnyEvent (); |
| 43 |
use AnyEvent::Util (); |
| 44 |
use AnyEvent::Socket (); |
| 45 |
use AnyEvent::Handle (); |
| 46 |
|
| 47 |
use base Exporter::; |
| 48 |
|
| 49 |
our $VERSION = '1.0'; |
| 50 |
|
| 51 |
our @EXPORT = qw(http_get http_request); |
| 52 |
|
| 53 |
our $USERAGENT = "Mozilla/5.0 (compatible; AnyEvent::HTTP/$VERSION; +http://software.schmorp.de/pkg/AnyEvent)"; |
| 54 |
our $MAX_RECURSE = 10; |
| 55 |
our $MAX_PERSISTENT = 8; |
| 56 |
our $PERSISTENT_TIMEOUT = 2; |
| 57 |
our $TIMEOUT = 300; |
| 58 |
|
| 59 |
# changing these is evil |
| 60 |
our $MAX_PERSISTENT_PER_HOST = 2; |
| 61 |
our $MAX_PER_HOST = 4; |
| 62 |
|
| 63 |
our $PROXY; |
| 64 |
|
| 65 |
my %KA_COUNT; # number of open keep-alive connections per host |
| 66 |
my %CO_SLOT; # number of open connections, and wait queue, per host |
| 67 |
|
| 68 |
=item http_get $url, key => value..., $cb->($data, $headers) |
| 69 |
|
| 70 |
Executes an HTTP-GET request. See the http_request function for details on |
| 71 |
additional parameters. |
| 72 |
|
| 73 |
=item http_head $url, key => value..., $cb->($data, $headers) |
| 74 |
|
| 75 |
Executes an HTTP-HEAD request. See the http_request function for details on |
| 76 |
additional parameters. |
| 77 |
|
| 78 |
=item http_post $url, $body, key => value..., $cb->($data, $headers) |
| 79 |
|
| 80 |
Executes an HTTP-POST request with a request body of C<$bod>. See the |
| 81 |
http_request function for details on additional parameters. |
| 82 |
|
| 83 |
=item http_request $method => $url, key => value..., $cb->($data, $headers) |
| 84 |
|
| 85 |
Executes a HTTP request of type C<$method> (e.g. C<GET>, C<POST>). The URL |
| 86 |
must be an absolute http or https URL. |
| 87 |
|
| 88 |
The callback will be called with the response data as first argument |
| 89 |
(or C<undef> if it wasn't available due to errors), and a hash-ref with |
| 90 |
response headers as second argument. |
| 91 |
|
| 92 |
All the headers in that hash are lowercased. In addition to the response |
| 93 |
headers, the three "pseudo-headers" C<HTTPVersion>, C<Status> and |
| 94 |
C<Reason> contain the three parts of the HTTP Status-Line of the same |
| 95 |
name. If the server sends a header multiple lines, then their contents |
| 96 |
will be joined together with C<\x00>. |
| 97 |
|
| 98 |
If an internal error occurs, such as not being able to resolve a hostname, |
| 99 |
then C<$data> will be C<undef>, C<< $headers->{Status} >> will be C<599> |
| 100 |
and the C<Reason> pseudo-header will contain an error message. |
| 101 |
|
| 102 |
A typical callback might look like this: |
| 103 |
|
| 104 |
sub { |
| 105 |
my ($body, $hdr) = @_; |
| 106 |
|
| 107 |
if ($hdr->{Status} =~ /^2/) { |
| 108 |
... everything should be ok |
| 109 |
} else { |
| 110 |
print "error, $hdr->{Status} $hdr->{Reason}\n"; |
| 111 |
} |
| 112 |
} |
| 113 |
|
| 114 |
Additional parameters are key-value pairs, and are fully optional. They |
| 115 |
include: |
| 116 |
|
| 117 |
=over 4 |
| 118 |
|
| 119 |
=item recurse => $count (default: $MAX_RECURSE) |
| 120 |
|
| 121 |
Whether to recurse requests or not, e.g. on redirects, authentication |
| 122 |
retries and so on, and how often to do so. |
| 123 |
|
| 124 |
=item headers => hashref |
| 125 |
|
| 126 |
The request headers to use. Currently, C<http_request> may provide its |
| 127 |
own C<Host:>, C<Content-Length:>, C<Connection:> and C<Cookie:> headers |
| 128 |
and will provide defaults for C<User-Agent:> and C<Referer:>. |
| 129 |
|
| 130 |
=item timeout => $seconds |
| 131 |
|
| 132 |
The time-out to use for various stages - each connect attempt will reset |
| 133 |
the timeout, as will read or write activity. Default timeout is 5 minutes. |
| 134 |
|
| 135 |
=item proxy => [$host, $port[, $scheme]] or undef |
| 136 |
|
| 137 |
Use the given http proxy for all requests. If not specified, then the |
| 138 |
default proxy (as specified by C<$ENV{http_proxy}>) is used. |
| 139 |
|
| 140 |
C<$scheme> must be either missing or C<http> for HTTP, or C<https> for |
| 141 |
HTTPS. |
| 142 |
|
| 143 |
=item body => $string |
| 144 |
|
| 145 |
The request body, usually empty. Will be-sent as-is (future versions of |
| 146 |
this module might offer more options). |
| 147 |
|
| 148 |
=item cookie_jar => $hash_ref |
| 149 |
|
| 150 |
Passing this parameter enables (simplified) cookie-processing, loosely |
| 151 |
based on the original netscape specification. |
| 152 |
|
| 153 |
The C<$hash_ref> must be an (initially empty) hash reference which will |
| 154 |
get updated automatically. It is possible to save the cookie_jar to |
| 155 |
persistent storage with something like JSON or Storable, but this is not |
| 156 |
recommended, as expire times are currently being ignored. |
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|
| 158 |
Note that this cookie implementation is not of very high quality, nor |
| 159 |
meant to be complete. If you want complete cookie management you have to |
| 160 |
do that on your own. C<cookie_jar> is meant as a quick fix to get some |
| 161 |
cookie-using sites working. Cookies are a privacy disaster, do not use |
| 162 |
them unless required to. |
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|
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=back |
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|
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Example: make a simple HTTP GET request for http://www.nethype.de/ |
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|
| 168 |
http_request GET => "http://www.nethype.de/", sub { |
| 169 |
my ($body, $hdr) = @_; |
| 170 |
print "$body\n"; |
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}; |
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|
| 173 |
Example: make a HTTP HEAD request on https://www.google.com/, use a |
| 174 |
timeout of 30 seconds. |
| 175 |
|
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http_request |
| 177 |
GET => "https://www.google.com", |
| 178 |
timeout => 30, |
| 179 |
sub { |
| 180 |
my ($body, $hdr) = @_; |
| 181 |
use Data::Dumper; |
| 182 |
print Dumper $hdr; |
| 183 |
} |
| 184 |
; |
| 185 |
|
| 186 |
=cut |
| 187 |
|
| 188 |
sub _slot_schedule; |
| 189 |
sub _slot_schedule($) { |
| 190 |
my $host = shift; |
| 191 |
|
| 192 |
while ($CO_SLOT{$host}[0] < $MAX_PER_HOST) { |
| 193 |
if (my $cb = shift @{ $CO_SLOT{$host}[1] }) { |
| 194 |
# somebody wants that slot |
| 195 |
++$CO_SLOT{$host}[0]; |
| 196 |
|
| 197 |
$cb->(AnyEvent::Util::guard { |
| 198 |
--$CO_SLOT{$host}[0]; |
| 199 |
_slot_schedule $host; |
| 200 |
}); |
| 201 |
} else { |
| 202 |
# nobody wants the slot, maybe we can forget about it |
| 203 |
delete $CO_SLOT{$host} unless $CO_SLOT{$host}[0]; |
| 204 |
last; |
| 205 |
} |
| 206 |
} |
| 207 |
} |
| 208 |
|
| 209 |
# wait for a free slot on host, call callback |
| 210 |
sub _get_slot($$) { |
| 211 |
push @{ $CO_SLOT{$_[0]}[1] }, $_[1]; |
| 212 |
|
| 213 |
_slot_schedule $_[0]; |
| 214 |
} |
| 215 |
|
| 216 |
sub http_request($$$;@) { |
| 217 |
my $cb = pop; |
| 218 |
my ($method, $url, %arg) = @_; |
| 219 |
|
| 220 |
my %hdr; |
| 221 |
|
| 222 |
$method = uc $method; |
| 223 |
|
| 224 |
if (my $hdr = $arg{headers}) { |
| 225 |
while (my ($k, $v) = each %$hdr) { |
| 226 |
$hdr{lc $k} = $v; |
| 227 |
} |
| 228 |
} |
| 229 |
|
| 230 |
my $recurse = exists $arg{recurse} ? $arg{recurse} : $MAX_RECURSE; |
| 231 |
|
| 232 |
return $cb->(undef, { Status => 599, Reason => "recursion limit reached" }) |
| 233 |
if $recurse < 0; |
| 234 |
|
| 235 |
my $proxy = $arg{proxy} || $PROXY; |
| 236 |
my $timeout = $arg{timeout} || $TIMEOUT; |
| 237 |
|
| 238 |
$hdr{"user-agent"} ||= $USERAGENT; |
| 239 |
|
| 240 |
my ($scheme, $authority, $upath, $query, $fragment) = |
| 241 |
$url =~ m|(?:([^:/?#]+):)?(?://([^/?#]*))?([^?#]*)(?:\?([^#]*))?(?:#(.*))?|; |
| 242 |
|
| 243 |
$scheme = lc $scheme; |
| 244 |
|
| 245 |
my $uport = $scheme eq "http" ? 80 |
| 246 |
: $scheme eq "https" ? 443 |
| 247 |
: return $cb->(undef, { Status => 599, Reason => "only http and https URL schemes supported" }); |
| 248 |
|
| 249 |
$hdr{referer} ||= "$scheme://$authority$upath"; # leave out fragment and query string, just a heuristic |
| 250 |
|
| 251 |
$authority =~ /^(?: .*\@ )? ([^\@:]+) (?: : (\d+) )?$/x |
| 252 |
or return $cb->(undef, { Status => 599, Reason => "unparsable URL" }); |
| 253 |
|
| 254 |
my $uhost = $1; |
| 255 |
$uport = $2 if defined $2; |
| 256 |
|
| 257 |
$uhost =~ s/^\[(.*)\]$/$1/; |
| 258 |
$upath .= "?$query" if length $query; |
| 259 |
|
| 260 |
$upath =~ s%^/?%/%; |
| 261 |
|
| 262 |
# cookie processing |
| 263 |
if (my $jar = $arg{cookie_jar}) { |
| 264 |
%$jar = () if $jar->{version} < 1; |
| 265 |
|
| 266 |
my @cookie; |
| 267 |
|
| 268 |
while (my ($chost, $v) = each %$jar) { |
| 269 |
next unless $chost eq substr $uhost, -length $chost; |
| 270 |
next unless $chost =~ /^\./; |
| 271 |
|
| 272 |
while (my ($cpath, $v) = each %$v) { |
| 273 |
next unless $cpath eq substr $upath, 0, length $cpath; |
| 274 |
|
| 275 |
while (my ($k, $v) = each %$v) { |
| 276 |
next if $scheme ne "https" && exists $v->{secure}; |
| 277 |
push @cookie, "$k=$v->{value}"; |
| 278 |
} |
| 279 |
} |
| 280 |
} |
| 281 |
|
| 282 |
$hdr{cookie} = join "; ", @cookie |
| 283 |
if @cookie; |
| 284 |
} |
| 285 |
|
| 286 |
my ($rhost, $rport, $rpath); # request host, port, path |
| 287 |
|
| 288 |
if ($proxy) { |
| 289 |
($rhost, $rport, $scheme) = @$proxy; |
| 290 |
$rpath = $url; |
| 291 |
} else { |
| 292 |
($rhost, $rport, $rpath) = ($uhost, $uport, $upath); |
| 293 |
$hdr{host} = $uhost; |
| 294 |
} |
| 295 |
|
| 296 |
$hdr{"content-length"} = length $arg{body}; |
| 297 |
|
| 298 |
my %state = (connect_guard => 1); |
| 299 |
|
| 300 |
_get_slot $uhost, sub { |
| 301 |
$state{slot_guard} = shift; |
| 302 |
|
| 303 |
return unless $state{connect_guard}; |
| 304 |
|
| 305 |
$state{connect_guard} = AnyEvent::Socket::tcp_connect $rhost, $rport, sub { |
| 306 |
$state{fh} = shift |
| 307 |
or return $cb->(undef, { Status => 599, Reason => "$!" }); |
| 308 |
|
| 309 |
delete $state{connect_guard}; # reduce memory usage, save a tree |
| 310 |
|
| 311 |
# get handle |
| 312 |
$state{handle} = new AnyEvent::Handle |
| 313 |
fh => $state{fh}, |
| 314 |
($scheme eq "https" ? (tls => "connect") : ()); |
| 315 |
|
| 316 |
# limit the number of persistent connections |
| 317 |
if ($KA_COUNT{$_[1]} < $MAX_PERSISTENT_PER_HOST) { |
| 318 |
++$KA_COUNT{$_[1]}; |
| 319 |
$state{handle}{ka_count_guard} = AnyEvent::Util::guard { --$KA_COUNT{$_[1]} }; |
| 320 |
$hdr{connection} = "keep-alive"; |
| 321 |
delete $hdr{connection}; # keep-alive not yet supported |
| 322 |
} else { |
| 323 |
delete $hdr{connection}; |
| 324 |
} |
| 325 |
|
| 326 |
# (re-)configure handle |
| 327 |
$state{handle}->timeout ($timeout); |
| 328 |
$state{handle}->on_error (sub { |
| 329 |
%state = (); |
| 330 |
$cb->(undef, { Status => 599, Reason => "$!" }); |
| 331 |
}); |
| 332 |
$state{handle}->on_eof (sub { |
| 333 |
%state = (); |
| 334 |
$cb->(undef, { Status => 599, Reason => "unexpected end-of-file" }); |
| 335 |
}); |
| 336 |
|
| 337 |
# send request |
| 338 |
$state{handle}->push_write ( |
| 339 |
"$method $rpath HTTP/1.0\015\012" |
| 340 |
. (join "", map "$_: $hdr{$_}\015\012", keys %hdr) |
| 341 |
. "\015\012" |
| 342 |
. (delete $arg{body}) |
| 343 |
); |
| 344 |
|
| 345 |
%hdr = (); # reduce memory usage, save a kitten |
| 346 |
|
| 347 |
# status line |
| 348 |
$state{handle}->push_read (line => qr/\015?\012/, sub { |
| 349 |
$_[1] =~ /^HTTP\/([0-9\.]+) \s+ ([0-9]{3}) \s+ ([^\015\012]+)/ix |
| 350 |
or return (%state = (), $cb->(undef, { Status => 599, Reason => "invalid server response ($_[1])" })); |
| 351 |
|
| 352 |
my %hdr = ( # response headers |
| 353 |
HTTPVersion => "\x00$1", |
| 354 |
Status => "\x00$2", |
| 355 |
Reason => "\x00$3", |
| 356 |
); |
| 357 |
|
| 358 |
# headers, could be optimized a bit |
| 359 |
$state{handle}->unshift_read (line => qr/\015?\012\015?\012/, sub { |
| 360 |
for ("$_[1]\012") { |
| 361 |
# we support spaces in field names, as lotus domino |
| 362 |
# creates them. |
| 363 |
$hdr{lc $1} .= "\x00$2" |
| 364 |
while /\G |
| 365 |
([^:\000-\037]+): |
| 366 |
[\011\040]* |
| 367 |
((?: [^\015\012]+ | \015?\012[\011\040] )*) |
| 368 |
\015?\012 |
| 369 |
/gxc; |
| 370 |
|
| 371 |
/\G$/ |
| 372 |
or return (%state = (), $cb->(undef, { Status => 599, Reason => "garbled response headers" })); |
| 373 |
} |
| 374 |
|
| 375 |
substr $_, 0, 1, "" |
| 376 |
for values %hdr; |
| 377 |
|
| 378 |
my $finish = sub { |
| 379 |
%state = (); |
| 380 |
|
| 381 |
# set-cookie processing |
| 382 |
if ($arg{cookie_jar} && exists $hdr{"set-cookie"}) { |
| 383 |
for (split /\x00/, $hdr{"set-cookie"}) { |
| 384 |
my ($cookie, @arg) = split /;\s*/; |
| 385 |
my ($name, $value) = split /=/, $cookie, 2; |
| 386 |
my %kv = (value => $value, map { split /=/, $_, 2 } @arg); |
| 387 |
|
| 388 |
my $cdom = (delete $kv{domain}) || $uhost; |
| 389 |
my $cpath = (delete $kv{path}) || "/"; |
| 390 |
|
| 391 |
$cdom =~ s/^.?/./; # make sure it starts with a "." |
| 392 |
|
| 393 |
next if $cdom =~ /\.$/; |
| 394 |
|
| 395 |
# this is not rfc-like and not netscape-like. go figure. |
| 396 |
my $ndots = $cdom =~ y/.//; |
| 397 |
next if $ndots < ($cdom =~ /\.[^.][^.]\.[^.][^.]$/ ? 3 : 2); |
| 398 |
|
| 399 |
# store it |
| 400 |
$arg{cookie_jar}{version} = 1; |
| 401 |
$arg{cookie_jar}{$cdom}{$cpath}{$name} = \%kv; |
| 402 |
} |
| 403 |
} |
| 404 |
|
| 405 |
if ($_[1]{Status} =~ /^30[12]$/ && $recurse) { |
| 406 |
# microsoft and other assholes don't give a shit for following standards, |
| 407 |
# try to support a common form of broken Location header. |
| 408 |
$_[1]{location} =~ s%^/%$scheme://$uhost:$uport/%; |
| 409 |
|
| 410 |
http_request ($method, $_[1]{location}, %arg, recurse => $recurse - 1, $cb); |
| 411 |
} else { |
| 412 |
$cb->($_[0], $_[1]); |
| 413 |
} |
| 414 |
}; |
| 415 |
|
| 416 |
if ($hdr{Status} =~ /^(?:1..|204|304)$/ or $method eq "HEAD") { |
| 417 |
$finish->(undef, \%hdr); |
| 418 |
} else { |
| 419 |
if (exists $hdr{"content-length"}) { |
| 420 |
$_[0]->unshift_read (chunk => $hdr{"content-length"}, sub { |
| 421 |
# could cache persistent connection now |
| 422 |
if ($hdr{connection} =~ /\bkeep-alive\b/i) { |
| 423 |
# but we don't, due to misdesigns, this is annoyingly complex |
| 424 |
}; |
| 425 |
|
| 426 |
$finish->($_[1], \%hdr); |
| 427 |
}); |
| 428 |
} else { |
| 429 |
# too bad, need to read until we get an error or EOF, |
| 430 |
# no way to detect winged data. |
| 431 |
$_[0]->on_error (sub { |
| 432 |
$finish->($_[0]{rbuf}, \%hdr); |
| 433 |
}); |
| 434 |
$_[0]->on_eof (undef); |
| 435 |
$_[0]->on_read (sub { }); |
| 436 |
} |
| 437 |
} |
| 438 |
}); |
| 439 |
}); |
| 440 |
}, sub { |
| 441 |
$timeout |
| 442 |
}; |
| 443 |
}; |
| 444 |
|
| 445 |
defined wantarray && AnyEvent::Util::guard { %state = () } |
| 446 |
} |
| 447 |
|
| 448 |
sub http_get($$;@) { |
| 449 |
unshift @_, "GET"; |
| 450 |
&http_request |
| 451 |
} |
| 452 |
|
| 453 |
sub http_head($$;@) { |
| 454 |
unshift @_, "HEAD"; |
| 455 |
&http_request |
| 456 |
} |
| 457 |
|
| 458 |
sub http_post($$$;@) { |
| 459 |
unshift @_, "POST", "body"; |
| 460 |
&http_request |
| 461 |
} |
| 462 |
|
| 463 |
=back |
| 464 |
|
| 465 |
=head2 GLOBAL FUNCTIONS AND VARIABLES |
| 466 |
|
| 467 |
=over 4 |
| 468 |
|
| 469 |
=item AnyEvent::HTTP::set_proxy "proxy-url" |
| 470 |
|
| 471 |
Sets the default proxy server to use. The proxy-url must begin with a |
| 472 |
string of the form C<http://host:port> (optionally C<https:...>). |
| 473 |
|
| 474 |
=item $AnyEvent::HTTP::MAX_RECURSE |
| 475 |
|
| 476 |
The default value for the C<recurse> request parameter (default: C<10>). |
| 477 |
|
| 478 |
=item $AnyEvent::HTTP::USERAGENT |
| 479 |
|
| 480 |
The default value for the C<User-Agent> header (the default is |
| 481 |
C<Mozilla/5.0 (compatible; AnyEvent::HTTP/$VERSION; +http://software.schmorp.de/pkg/AnyEvent)>). |
| 482 |
|
| 483 |
=item $AnyEvent::HTTP::MAX_PERSISTENT |
| 484 |
|
| 485 |
The maximum number of persistent connections to keep open (default: 8). |
| 486 |
|
| 487 |
Not implemented currently. |
| 488 |
|
| 489 |
=item $AnyEvent::HTTP::PERSISTENT_TIMEOUT |
| 490 |
|
| 491 |
The maximum time to cache a persistent connection, in seconds (default: 2). |
| 492 |
|
| 493 |
Not implemented currently. |
| 494 |
|
| 495 |
=back |
| 496 |
|
| 497 |
=cut |
| 498 |
|
| 499 |
sub set_proxy($) { |
| 500 |
$PROXY = [$2, $3 || 3128, $1] if $_[0] =~ m%^(https?):// ([^:/]+) (?: : (\d*) )?%ix; |
| 501 |
} |
| 502 |
|
| 503 |
# initialise proxy from environment |
| 504 |
set_proxy $ENV{http_proxy}; |
| 505 |
|
| 506 |
=head1 SEE ALSO |
| 507 |
|
| 508 |
L<AnyEvent>. |
| 509 |
|
| 510 |
=head1 AUTHOR |
| 511 |
|
| 512 |
Marc Lehmann <schmorp@schmorp.de> |
| 513 |
http://home.schmorp.de/ |
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|
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=cut |
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|
| 517 |
1 |
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