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Revision 1.6 by root, Wed Jun 4 12:05:45 2008 UTC vs.
Revision 1.18 by root, Fri Jun 6 16:23:57 2008 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.
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.
13 32
14=head2 METHODS 33=head2 METHODS
15 34
16=over 4 35=over 4
17 36
… …
29use AnyEvent::Socket (); 48use AnyEvent::Socket ();
30use AnyEvent::Handle (); 49use AnyEvent::Handle ();
31 50
32use base Exporter::; 51use base Exporter::;
33 52
34our $VERSION = '1.0'; 53our $VERSION = '1.01';
35 54
36our @EXPORT = qw(http_get http_request); 55our @EXPORT = qw(http_get http_post http_head http_request);
37 56
38our $USERAGENT = "Mozilla/5.0 (compatible; AnyEvent::HTTP/$VERSION; +http://software.schmorp.de/pkg/AnyEvent)"; 57our $USERAGENT = "Mozilla/5.0 (compatible; AnyEvent::HTTP/$VERSION; +http://software.schmorp.de/pkg/AnyEvent)";
39our $MAX_RECURSE = 10; 58our $MAX_RECURSE = 10;
40our $MAX_PERSISTENT = 8; 59our $MAX_PERSISTENT = 8;
41our $PERSISTENT_TIMEOUT = 2; 60our $PERSISTENT_TIMEOUT = 2;
42our $TIMEOUT = 300; 61our $TIMEOUT = 300;
43 62
44# changing these is evil 63# changing these is evil
45our $MAX_PERSISTENT_PER_HOST = 2; 64our $MAX_PERSISTENT_PER_HOST = 2;
46our $MAX_PER_HOST = 4; # not respected yet :( 65our $MAX_PER_HOST = 4;
47 66
48our $PROXY; 67our $PROXY;
68our $ACTIVE = 0;
49 69
50my %KA_COUNT; # number of open keep-alive connections per host 70my %KA_COUNT; # number of open keep-alive connections per host
71my %CO_SLOT; # number of open connections, and wait queue, per host
51 72
52=item http_get $url, key => value..., $cb->($data, $headers) 73=item http_get $url, key => value..., $cb->($data, $headers)
53 74
54Executes an HTTP-GET request. See the http_request function for details on 75Executes an HTTP-GET request. See the http_request function for details on
55additional parameters. 76additional parameters.
… …
59Executes an HTTP-HEAD request. See the http_request function for details on 80Executes an HTTP-HEAD request. See the http_request function for details on
60additional parameters. 81additional parameters.
61 82
62=item http_post $url, $body, key => value..., $cb->($data, $headers) 83=item http_post $url, $body, key => value..., $cb->($data, $headers)
63 84
64Executes an HTTP-POST request with a requets body of C<$bod>. See the 85Executes an HTTP-POST request with a request body of C<$bod>. See the
65http_request function for details on additional parameters. 86http_request function for details on additional parameters.
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<$method> (e.g. C<GET>, C<POST>). The URL
… …
71 92
72The callback will be called with the response data as first argument 93The callback will be called with the response data as first argument
73(or C<undef> if it wasn't available due to errors), and a hash-ref with 94(or C<undef> if it wasn't available due to errors), and a hash-ref with
74response headers as second argument. 95response headers as second argument.
75 96
76All the headers in that has are lowercased. In addition to the response 97All the headers in that hash are lowercased. In addition to the response
77headers, the three "pseudo-headers" C<HTTPVersion>, C<Status> and 98headers, the three "pseudo-headers" C<HTTPVersion>, C<Status> and
78C<Reason> contain the three parts of the HTTP Status-Line of the same 99C<Reason> contain the three parts of the HTTP Status-Line of the same
79name. 100name. If the server sends a header multiple lines, then their contents
101will be joined together with C<\x00>.
80 102
81If an internal error occurs, such as not being able to resolve a hostname, 103If an internal error occurs, such as not being able to resolve a hostname,
82then C<$data> will be C<undef>, C<< $headers->{Status} >> will be C<599> 104then C<$data> will be C<undef>, C<< $headers->{Status} >> will be C<599>
83and the C<Reason> pseudo-header will contain an error message. 105and the C<Reason> pseudo-header will contain an error message.
84 106
… …
104Whether to recurse requests or not, e.g. on redirects, authentication 126Whether to recurse requests or not, e.g. on redirects, authentication
105retries and so on, and how often to do so. 127retries and so on, and how often to do so.
106 128
107=item headers => hashref 129=item headers => hashref
108 130
109The request headers to use. 131The request headers to use. Currently, C<http_request> may provide its
132own C<Host:>, C<Content-Length:>, C<Connection:> and C<Cookie:> headers
133and will provide defaults for C<User-Agent:> and C<Referer:>.
110 134
111=item timeout => $seconds 135=item timeout => $seconds
112 136
113The time-out to use for various stages - each connect attempt will reset 137The 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. 138the timeout, as will read or write activity. Default timeout is 5 minutes.
… …
124=item body => $string 148=item body => $string
125 149
126The request body, usually empty. Will be-sent as-is (future versions of 150The request body, usually empty. Will be-sent as-is (future versions of
127this module might offer more options). 151this module might offer more options).
128 152
153=item cookie_jar => $hash_ref
154
155Passing this parameter enables (simplified) cookie-processing, loosely
156based on the original netscape specification.
157
158The C<$hash_ref> must be an (initially empty) hash reference which will
159get updated automatically. It is possible to save the cookie_jar to
160persistent storage with something like JSON or Storable, but this is not
161recommended, as expire times are currently being ignored.
162
163Note that this cookie implementation is not of very high quality, nor
164meant to be complete. If you want complete cookie management you have to
165do that on your own. C<cookie_jar> is meant as a quick fix to get some
166cookie-using sites working. Cookies are a privacy disaster, do not use
167them unless required to.
168
129=back 169=back
130 170
131=back 171Example: make a simple HTTP GET request for http://www.nethype.de/
172
173 http_request GET => "http://www.nethype.de/", sub {
174 my ($body, $hdr) = @_;
175 print "$body\n";
176 };
177
178Example: make a HTTP HEAD request on https://www.google.com/, use a
179timeout of 30 seconds.
180
181 http_request
182 GET => "https://www.google.com",
183 timeout => 30,
184 sub {
185 my ($body, $hdr) = @_;
186 use Data::Dumper;
187 print Dumper $hdr;
188 }
189 ;
132 190
133=cut 191=cut
134 192
193sub _slot_schedule;
194sub _slot_schedule($) {
195 my $host = shift;
196
197 while ($CO_SLOT{$host}[0] < $MAX_PER_HOST) {
198 if (my $cb = shift @{ $CO_SLOT{$host}[1] }) {
199 # somebody wants that slot
200 ++$CO_SLOT{$host}[0];
201 ++$ACTIVE;
202
203 $cb->(AnyEvent::Util::guard {
204 --$ACTIVE;
205 --$CO_SLOT{$host}[0];
206 _slot_schedule $host;
207 });
208 } else {
209 # nobody wants the slot, maybe we can forget about it
210 delete $CO_SLOT{$host} unless $CO_SLOT{$host}[0];
211 last;
212 }
213 }
214}
215
216# wait for a free slot on host, call callback
217sub _get_slot($$) {
218 push @{ $CO_SLOT{$_[0]}[1] }, $_[1];
219
220 _slot_schedule $_[0];
221}
222
135sub http_request($$$;@) { 223sub http_request($$@) {
136 my $cb = pop; 224 my $cb = pop;
137 my ($method, $url, %arg) = @_; 225 my ($method, $url, %arg) = @_;
138 226
139 my %hdr; 227 my %hdr;
140 228
141 $method = uc $method; 229 $method = uc $method;
142 230
143 if (my $hdr = delete $arg{headers}) { 231 if (my $hdr = $arg{headers}) {
144 while (my ($k, $v) = each %$hdr) { 232 while (my ($k, $v) = each %$hdr) {
145 $hdr{lc $k} = $v; 233 $hdr{lc $k} = $v;
146 } 234 }
147 } 235 }
148 236
237 my $recurse = exists $arg{recurse} ? $arg{recurse} : $MAX_RECURSE;
238
239 return $cb->(undef, { Status => 599, Reason => "recursion limit reached" })
240 if $recurse < 0;
241
149 my $proxy = $arg{proxy} || $PROXY; 242 my $proxy = $arg{proxy} || $PROXY;
150 my $timeout = $arg{timeout} || $TIMEOUT; 243 my $timeout = $arg{timeout} || $TIMEOUT;
151 my $recurse = exists $arg{recurse} ? $arg{recurse} : $MAX_RECURSE;
152 244
153 $hdr{"user-agent"} ||= $USERAGENT; 245 $hdr{"user-agent"} ||= $USERAGENT;
154 246
155 my ($host, $port, $path, $scheme); 247 my ($scheme, $authority, $upath, $query, $fragment) =
248 $url =~ m|(?:([^:/?#]+):)?(?://([^/?#]*))?([^?#]*)(?:\?([^#]*))?(?:#(.*))?|;
249
250 $scheme = lc $scheme;
251
252 my $uport = $scheme eq "http" ? 80
253 : $scheme eq "https" ? 443
254 : return $cb->(undef, { Status => 599, Reason => "only http and https URL schemes supported" });
255
256 $hdr{referer} ||= "$scheme://$authority$upath"; # leave out fragment and query string, just a heuristic
257
258 $authority =~ /^(?: .*\@ )? ([^\@:]+) (?: : (\d+) )?$/x
259 or return $cb->(undef, { Status => 599, Reason => "unparsable URL" });
260
261 my $uhost = $1;
262 $uport = $2 if defined $2;
263
264 $uhost =~ s/^\[(.*)\]$/$1/;
265 $upath .= "?$query" if length $query;
266
267 $upath =~ s%^/?%/%;
268
269 # cookie processing
270 if (my $jar = $arg{cookie_jar}) {
271 %$jar = () if $jar->{version} < 1;
272
273 my @cookie;
274
275 while (my ($chost, $v) = each %$jar) {
276 next unless $chost eq substr $uhost, -length $chost;
277 next unless $chost =~ /^\./;
278
279 while (my ($cpath, $v) = each %$v) {
280 next unless $cpath eq substr $upath, 0, length $cpath;
281
282 while (my ($k, $v) = each %$v) {
283 next if $scheme ne "https" && exists $v->{secure};
284 push @cookie, "$k=$v->{value}";
285 }
286 }
287 }
288
289 $hdr{cookie} = join "; ", @cookie
290 if @cookie;
291 }
292
293 my ($rhost, $rport, $rpath); # request host, port, path
156 294
157 if ($proxy) { 295 if ($proxy) {
158 ($host, $port, $scheme) = @$proxy; 296 ($rhost, $rport, $scheme) = @$proxy;
159 $path = $url; 297 $rpath = $url;
160 } else { 298 } else {
161 ($scheme, my $authority, $path, my $query, my $fragment) = 299 ($rhost, $rport, $rpath) = ($uhost, $uport, $upath);
162 $url =~ m|(?:([^:/?#]+):)?(?://([^/?#]*))?([^?#]*)(?:\?([^#]*))?(?:#(.*))?|;
163
164 $port = $scheme eq "http" ? 80
165 : $scheme eq "https" ? 443
166 : croak "$url: only http and https URLs supported";
167
168 $authority =~ /^(?: .*\@ )? ([^\@:]+) (?: : (\d+) )?$/x
169 or croak "$authority: unparsable URL";
170
171 $host = $1;
172 $port = $2 if defined $2;
173
174 $host =~ s/^\[(.*)\]$/$1/;
175 $path .= "?$query" if length $query;
176
177 $path = "/" unless $path;
178
179 $hdr{host} = $host = lc $host; 300 $hdr{host} = $uhost;
180 } 301 }
181 302
182 $scheme = lc $scheme;
183
184 my %state;
185
186 $state{body} = delete $arg{body};
187
188 $hdr{"content-length"} = length $state{body}; 303 $hdr{"content-length"} = length $arg{body};
189 304
305 my %state = (connect_guard => 1);
306
307 _get_slot $uhost, sub {
308 $state{slot_guard} = shift;
309
310 return unless $state{connect_guard};
311
190 $state{connect_guard} = AnyEvent::Socket::tcp_connect $host, $port, sub { 312 $state{connect_guard} = AnyEvent::Socket::tcp_connect $rhost, $rport, sub {
191 $state{fh} = shift 313 $state{fh} = shift
192 or return $cb->(undef, { Status => 599, Reason => "$!" }); 314 or return $cb->(undef, { Status => 599, Reason => "$!" });
193 315
194 delete $state{connect_guard}; # reduce memory usage, save a tree 316 delete $state{connect_guard}; # reduce memory usage, save a tree
195 317
196 # get handle 318 # get handle
197 $state{handle} = new AnyEvent::Handle 319 $state{handle} = new AnyEvent::Handle
198 fh => $state{fh}, 320 fh => $state{fh},
199 ($scheme eq "https" ? (tls => "connect") : ()); 321 ($scheme eq "https" ? (tls => "connect") : ());
200 322
201 # limit the number of persistent connections 323 # limit the number of persistent connections
202 if ($KA_COUNT{$_[1]} < $MAX_PERSISTENT_PER_HOST) { 324 if ($KA_COUNT{$_[1]} < $MAX_PERSISTENT_PER_HOST) {
203 ++$KA_COUNT{$_[1]}; 325 ++$KA_COUNT{$_[1]};
204 $state{handle}{ka_count_guard} = AnyEvent::Util::guard { --$KA_COUNT{$_[1]} }; 326 $state{handle}{ka_count_guard} = AnyEvent::Util::guard { --$KA_COUNT{$_[1]} };
205 $hdr{connection} = "keep-alive"; 327 $hdr{connection} = "keep-alive";
206 delete $hdr{connection}; # keep-alive not yet supported 328 delete $hdr{connection}; # keep-alive not yet supported
207 } else { 329 } else {
208 delete $hdr{connection}; 330 delete $hdr{connection};
209 } 331 }
210 332
211 # (re-)configure handle 333 # (re-)configure handle
212 $state{handle}->timeout ($timeout); 334 $state{handle}->timeout ($timeout);
213 $state{handle}->on_error (sub { 335 $state{handle}->on_error (sub {
336 my $errno = "$!";
214 %state = (); 337 %state = ();
215 $cb->(undef, { Status => 599, Reason => "$!" }); 338 $cb->(undef, { Status => 599, Reason => $errno });
216 }); 339 });
217 $state{handle}->on_eof (sub { 340 $state{handle}->on_eof (sub {
218 %state = (); 341 %state = ();
219 $cb->(undef, { Status => 599, Reason => "unexpected end-of-file" }); 342 $cb->(undef, { Status => 599, Reason => "unexpected end-of-file" });
220 }); 343 });
221 344
222 # send request 345 # send request
223 $state{handle}->push_write ( 346 $state{handle}->push_write (
224 "$method $path HTTP/1.0\015\012" 347 "$method $rpath HTTP/1.0\015\012"
225 . (join "", map "$_: $hdr{$_}\015\012", keys %hdr) 348 . (join "", map "$_: $hdr{$_}\015\012", keys %hdr)
226 . "\015\012" 349 . "\015\012"
227 . (delete $state{body}) 350 . (delete $arg{body})
228 );
229
230 %hdr = (); # reduce memory usage, save a kitten
231
232 # status line
233 $state{handle}->push_read (line => qr/\015?\012/, sub {
234 $_[1] =~ /^HTTP\/([0-9\.]+) \s+ ([0-9]{3}) \s+ ([^\015\012]+)/ix
235 or return (%state = (), $cb->(undef, { Status => 599, Reason => "invalid server response ($_[1])" }));
236
237 my %hdr = ( # response headers
238 HTTPVersion => ",$1",
239 Status => ",$2",
240 Reason => ",$3",
241 ); 351 );
242 352
353 %hdr = (); # reduce memory usage, save a kitten
354
355 # status line
356 $state{handle}->push_read (line => qr/\015?\012/, sub {
357 $_[1] =~ /^HTTP\/([0-9\.]+) \s+ ([0-9]{3}) \s+ ([^\015\012]+)/ix
358 or return (%state = (), $cb->(undef, { Status => 599, Reason => "invalid server response ($_[1])" }));
359
360 my %hdr = ( # response headers
361 HTTPVersion => "\x00$1",
362 Status => "\x00$2",
363 Reason => "\x00$3",
364 );
365
243 # headers, could be optimized a bit 366 # headers, could be optimized a bit
244 $state{handle}->unshift_read (line => qr/\015?\012\015?\012/, sub { 367 $state{handle}->unshift_read (line => qr/\015?\012\015?\012/, sub {
245 for ("$_[1]\012") { 368 for ("$_[1]\012") {
246 # we support spaces in field names, as lotus domino 369 # we support spaces in field names, as lotus domino
247 # creates them. 370 # creates them.
248 $hdr{lc $1} .= ",$2" 371 $hdr{lc $1} .= "\x00$2"
249 while /\G 372 while /\G
250 ([^:\000-\037]+): 373 ([^:\000-\037]+):
251 [\011\040]* 374 [\011\040]*
252 ((?: [^\015\012]+ | \015?\012[\011\040] )*) 375 ((?: [^\015\012]+ | \015?\012[\011\040] )*)
253 \015?\012 376 \015?\012
254 /gxc; 377 /gxc;
255 378
256 /\G$/ 379 /\G$/
257 or return $cb->(undef, { Status => 599, Reason => "garbled response headers" }); 380 or return (%state = (), $cb->(undef, { Status => 599, Reason => "garbled response headers" }));
258 } 381 }
259 382
260 substr $_, 0, 1, "" 383 substr $_, 0, 1, ""
261 for values %hdr; 384 for values %hdr;
262 385
263 if ($method eq "HEAD") { 386 my $finish = sub {
264 %state = (); 387 %state = ();
265 $cb->(undef, \%hdr); 388
266 } else { 389 # set-cookie processing
267 if (exists $hdr{"content-length"}) { 390 if ($arg{cookie_jar} && exists $hdr{"set-cookie"}) {
268 $_[0]->unshift_read (chunk => $hdr{"content-length"}, sub { 391 for (split /\x00/, $hdr{"set-cookie"}) {
269 # could cache persistent connection now 392 my ($cookie, @arg) = split /;\s*/;
270 if ($hdr{connection} =~ /\bkeep-alive\b/i) { 393 my ($name, $value) = split /=/, $cookie, 2;
271 # but we don't, due to misdesigns, this is annoyingly complex 394 my %kv = (value => $value, map { split /=/, $_, 2 } @arg);
395
396 my $cdom = (delete $kv{domain}) || $uhost;
397 my $cpath = (delete $kv{path}) || "/";
398
399 $cdom =~ s/^.?/./; # make sure it starts with a "."
400
401 next if $cdom =~ /\.$/;
402
403 # this is not rfc-like and not netscape-like. go figure.
404 my $ndots = $cdom =~ y/.//;
405 next if $ndots < ($cdom =~ /\.[^.][^.]\.[^.][^.]$/ ? 3 : 2);
406
407 # store it
408 $arg{cookie_jar}{version} = 1;
409 $arg{cookie_jar}{$cdom}{$cpath}{$name} = \%kv;
272 }; 410 }
273
274 %state = ();
275 $cb->($_[1], \%hdr);
276 }); 411 }
412
413 if ($_[1]{Status} =~ /^30[12]$/ && $recurse) {
414 # microsoft and other assholes don't give a shit for following standards,
415 # try to support a common form of broken Location header.
416 $_[1]{location} =~ s%^/%$scheme://$uhost:$uport/%;
417
418 http_request ($method, $_[1]{location}, %arg, recurse => $recurse - 1, $cb);
419 } else {
420 $cb->($_[0], $_[1]);
421 }
422 };
423
424 if ($hdr{Status} =~ /^(?:1..|204|304)$/ or $method eq "HEAD") {
425 $finish->(undef, \%hdr);
277 } else { 426 } else {
427 if (exists $hdr{"content-length"}) {
428 $_[0]->unshift_read (chunk => $hdr{"content-length"}, sub {
429 # could cache persistent connection now
430 if ($hdr{connection} =~ /\bkeep-alive\b/i) {
431 # but we don't, due to misdesigns, this is annoyingly complex
432 };
433
434 $finish->($_[1], \%hdr);
435 });
436 } else {
278 # too bad, need to read until we get an error or EOF, 437 # too bad, need to read until we get an error or EOF,
279 # no way to detect winged data. 438 # no way to detect winged data.
280 $_[0]->on_error (sub { 439 $_[0]->on_error (sub {
281 %state = ();
282 $cb->($_[0]{rbuf}, \%hdr); 440 $finish->($_[0]{rbuf}, \%hdr);
283 }); 441 });
284 $_[0]->on_eof (undef); 442 $_[0]->on_eof (undef);
285 $_[0]->on_read (sub { }); 443 $_[0]->on_read (sub { });
444 }
286 } 445 }
287 } 446 });
288 }); 447 });
448 }, sub {
449 $timeout
289 }); 450 };
290 }, sub {
291 $timeout
292 }; 451 };
293 452
294 defined wantarray && AnyEvent::Util::guard { %state = () } 453 defined wantarray && AnyEvent::Util::guard { %state = () }
295} 454}
296 455
297sub http_get($$;@) { 456sub http_get($@) {
298 unshift @_, "GET"; 457 unshift @_, "GET";
299 &http_request 458 &http_request
300} 459}
301 460
302sub http_head($$;@) { 461sub http_head($@) {
303 unshift @_, "HEAD"; 462 unshift @_, "HEAD";
304 &http_request 463 &http_request
305} 464}
306 465
307sub http_post($$$;@) { 466sub http_post($$@) {
308 unshift @_, "POST", "body"; 467 unshift @_, "POST", "body";
309 &http_request 468 &http_request
310} 469}
311 470
471=back
472
312=head2 GLOBAL FUNCTIONS AND VARIABLES 473=head2 GLOBAL FUNCTIONS AND VARIABLES
313 474
314=over 4 475=over 4
315 476
316=item AnyEvent::HTTP::set_proxy "proxy-url" 477=item AnyEvent::HTTP::set_proxy "proxy-url"
… …
337 498
338The maximum time to cache a persistent connection, in seconds (default: 2). 499The maximum time to cache a persistent connection, in seconds (default: 2).
339 500
340Not implemented currently. 501Not implemented currently.
341 502
503=item $AnyEvent::HTTP::ACTIVE
504
505The number of active connections. This is not the number of currently
506running requests, but the number of currently open and non-idle TCP
507connections. This number of can be useful for load-leveling.
508
342=back 509=back
343 510
344=cut 511=cut
345 512
346sub set_proxy($) { 513sub set_proxy($) {
… …
354 521
355L<AnyEvent>. 522L<AnyEvent>.
356 523
357=head1 AUTHOR 524=head1 AUTHOR
358 525
359 Marc Lehmann <schmorp@schmorp.de> 526 Marc Lehmann <schmorp@schmorp.de>
360 http://home.schmorp.de/ 527 http://home.schmorp.de/
361 528
362=cut 529=cut
363 530
3641 5311
365 532

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