1/* Part of SWI-Prolog 2 3 Author: Jan Wielemaker 4 E-mail: J.Wielemaker@vu.nl 5 WWW: http://www.swi-prolog.org 6 Copyright (c) 2002-2020, University of Amsterdam 7 VU University Amsterdam 8 All rights reserved. 9 10 Redistribution and use in source and binary forms, with or without 11 modification, are permitted provided that the following conditions 12 are met: 13 14 1. Redistributions of source code must retain the above copyright 15 notice, this list of conditions and the following disclaimer. 16 17 2. Redistributions in binary form must reproduce the above copyright 18 notice, this list of conditions and the following disclaimer in 19 the documentation and/or other materials provided with the 20 distribution. 21 22 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 23 "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 24 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 25 FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 26 COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 27 INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 28 BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 29 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 30 CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 32 ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 33 POSSIBILITY OF SUCH DAMAGE. 34*/ 35 36:- module(http_header, 37 [ http_read_request/2, % +Stream, -Request 38 http_read_reply_header/2, % +Stream, -Reply 39 http_reply/2, % +What, +Stream 40 http_reply/3, % +What, +Stream, +HdrExtra 41 http_reply/4, % +What, +Stream, +HdrExtra, -Code 42 http_reply/5, % +What, +Stream, +HdrExtra, +Context, 43 % -Code 44 http_reply/6, % +What, +Stream, +HdrExtra, +Context, 45 % +Request, -Code 46 http_reply_header/3, % +Stream, +What, +HdrExtra 47 http_status_reply/4, % +Status, +Out, +HdrExtra, -Code 48 http_status_reply/5, % +Status, +Out, +HdrExtra, 49 % +Context, -Code 50 51 http_timestamp/2, % +Time, -HTTP string 52 53 http_post_data/3, % +Stream, +Data, +HdrExtra 54 55 http_read_header/2, % +Fd, -Header 56 http_parse_header/2, % +Codes, -Header 57 http_parse_header_value/3, % +Header, +HeaderValue, -MediaTypes 58 http_join_headers/3, % +Default, +InHdr, -OutHdr 59 http_update_encoding/3, % +HeaderIn, -Encoding, -HeaderOut 60 http_update_connection/4, % +HeaderIn, +Request, -Connection, -HeaderOut 61 http_update_transfer/4 % +HeaderIn, +Request, -Transfer, -HeaderOut 62 ]). 63:- autoload(html_write, 64 [ print_html/2, print_html/1, page/4, html/3, 65 html_print_length/2 66 ]). 67:- if(exists_source(http_exception)). 68:- autoload(http_exception,[map_exception_to_http_status/4]). 69:- endif. 70:- autoload(mimepack,[mime_pack/3]). 71:- autoload(mimetype,[file_mime_type/2]). 72:- autoload(library(apply),[maplist/2]). 73:- autoload(library(base64),[base64/2]). 74:- use_module(library(debug),[debug/3,debugging/1]). 75:- autoload(library(error),[syntax_error/1,domain_error/2]). 76:- autoload(library(lists),[append/3,member/2,select/3,delete/3]). 77:- autoload(library(memfile), 78 [ new_memory_file/1, open_memory_file/3, 79 free_memory_file/1, open_memory_file/4, 80 size_memory_file/3 81 ]). 82:- autoload(library(option),[option/3,option/2]). 83:- autoload(library(pairs),[pairs_values/2]). 84:- autoload(library(readutil), 85 [read_line_to_codes/2,read_line_to_codes/3]). 86:- autoload(library(sgml_write),[xml_write/3]). 87:- autoload(library(socket),[gethostname/1]). 88:- autoload(library(uri), 89 [ uri_components/2, uri_data/3, uri_encoded/3, uri_query_components/2 90 ]). 91:- autoload(library(url),[parse_url_search/2]). 92:- autoload(library(dcg/basics), 93 [ integer/3, atom/3, whites/2, blanks_to_nl/2, string/3, 94 number/3, blanks/2, float/3, nonblanks/3, eos/2 95 ]). 96:- use_module(library(settings),[setting/4,setting/2]). 97 98:- multifile 99 http:status_page/3, % +Status, +Context, -HTML 100 http:status_reply/3, % +Status, -Reply, +Options 101 http:serialize_reply/2, % +Reply, -Body 102 http:post_data_hook/3, % +Data, +Out, +HdrExtra 103 http:mime_type_encoding/2. % +MimeType, -Encoding 104 105% see http_update_transfer/4. 106 107:- setting(http:chunked_transfer, oneof([never,on_request,if_possible]), 108 on_request, 'When to use Transfer-Encoding: Chunked').
118:- discontiguous 119 term_expansion/2. 120 121 122 /******************************* 123 * READ REQUEST * 124 *******************************/
end_of_file if FdIn is at the end of input.
132http_read_request(In, Request) :-
133 catch(read_line_to_codes(In, Codes), E, true),
134 ( var(E)
135 -> ( Codes == end_of_file
136 -> debug(http(header), 'end-of-file', []),
137 Request = end_of_file
138 ; debug(http(header), 'First line: ~s', [Codes]),
139 Request = [input(In)|Request1],
140 phrase(request(In, Request1), Codes),
141 ( Request1 = [unknown(Text)|_]
142 -> string_codes(S, Text),
143 syntax_error(http_request(S))
144 ; true
145 )
146 )
147 ; ( debugging(http(request))
148 -> message_to_string(E, Msg),
149 debug(http(request), "Exception reading 1st line: ~s", [Msg])
150 ; true
151 ),
152 Request = end_of_file
153 ).161http_read_reply_header(In, [input(In)|Reply]) :- 162 read_line_to_codes(In, Codes), 163 ( Codes == end_of_file 164 -> debug(http(header), 'end-of-file', []), 165 throw(error(syntax(http_reply_header, end_of_file), _)) 166 ; debug(http(header), 'First line: ~s~n', [Codes]), 167 ( phrase(reply(In, Reply), Codes) 168 -> true 169 ; atom_codes(Header, Codes), 170 syntax_error(http_reply_header(Header)) 171 ) 172 ). 173 174 175 /******************************* 176 * FORMULATE REPLY * 177 *******************************/
html_write.plfile, but do not include modification time226http_reply(What, Out) :- 227 http_reply(What, Out, [connection(close)], _). 228 229http_reply(Data, Out, HdrExtra) :- 230 http_reply(Data, Out, HdrExtra, _Code). 231 232http_reply(Data, Out, HdrExtra, Code) :- 233 http_reply(Data, Out, HdrExtra, [], Code). 234 235http_reply(Data, Out, HdrExtra, Context, Code) :- 236 http_reply(Data, Out, HdrExtra, Context, [method(get)], Code). 237 238http_reply(Data, Out, HdrExtra, _Context, Request, Code) :- 239 byte_count(Out, C0), 240 memberchk(method(Method), Request), 241 catch(http_reply_data(Data, Out, HdrExtra, Method, Code), E, true), 242 !, 243 ( var(E) 244 -> true 245 ; ( E = error(io_error(write,_), _) 246 ; E = error(socket_error(_,_), _) 247 ) 248 -> byte_count(Out, C1), 249 Sent is C1 - C0, 250 throw(error(http_write_short(Data, Sent), _)) 251 ; E = error(timeout_error(write, _), _) 252 -> throw(E) 253 ; map_exception_to_http_status(E, Status, NewHdr, NewContext) 254 -> http_status_reply(Status, Out, NewHdr, NewContext, Request, Code) 255 ; throw(E) 256 ). 257http_reply(Status, Out, HdrExtra, Context, Request, Code) :- 258 http_status_reply(Status, Out, HdrExtra, Context, Request, Code). 259 260:- if(\+current_predicate(map_exception_to_http_status/4)). 261map_exception_to_http_status(_E, _Status, _NewHdr, _NewContext) :- 262 fail. 263:- endif. 264 265:- meta_predicate 266 if_no_head(, ).
275http_reply_data(Data, Out, HdrExtra, Method, Code) :- 276 http_reply_data_(Data, Out, HdrExtra, Method, Code), 277 flush_output(Out). 278 279http_reply_data_(html(HTML), Out, HdrExtra, Method, Code) :- 280 !, 281 phrase(reply_header(html(HTML), HdrExtra, Code), Header), 282 send_reply_header(Out, Header), 283 if_no_head(print_html(Out, HTML), Method). 284http_reply_data_(file(Type, File), Out, HdrExtra, Method, Code) :- 285 !, 286 phrase(reply_header(file(Type, File), HdrExtra, Code), Header), 287 reply_file(Out, File, Header, Method). 288http_reply_data_(gzip_file(Type, File), Out, HdrExtra, Method, Code) :- 289 !, 290 phrase(reply_header(gzip_file(Type, File), HdrExtra, Code), Header), 291 reply_file(Out, File, Header, Method). 292http_reply_data_(file(Type, File, Range), Out, HdrExtra, Method, Code) :- 293 !, 294 phrase(reply_header(file(Type, File, Range), HdrExtra, Code), Header), 295 reply_file_range(Out, File, Header, Range, Method). 296http_reply_data_(tmp_file(Type, File), Out, HdrExtra, Method, Code) :- 297 !, 298 phrase(reply_header(tmp_file(Type, File), HdrExtra, Code), Header), 299 reply_file(Out, File, Header, Method). 300http_reply_data_(bytes(Type, Bytes), Out, HdrExtra, Method, Code) :- 301 !, 302 phrase(reply_header(bytes(Type, Bytes), HdrExtra, Code), Header), 303 send_reply_header(Out, Header), 304 if_no_head(format(Out, '~s', [Bytes]), Method). 305http_reply_data_(stream(In, Len), Out, HdrExtra, Method, Code) :- 306 !, 307 phrase(reply_header(cgi_data(Len), HdrExtra, Code), Header), 308 copy_stream(Out, In, Header, Method, 0, end). 309http_reply_data_(cgi_stream(In, Len), Out, HdrExtra, Method, Code) :- 310 !, 311 http_read_header(In, CgiHeader), 312 seek(In, 0, current, Pos), 313 Size is Len - Pos, 314 http_join_headers(HdrExtra, CgiHeader, Hdr2), 315 phrase(reply_header(cgi_data(Size), Hdr2, Code), Header), 316 copy_stream(Out, In, Header, Method, 0, end). 317 318if_no_head(_, head) :- 319 !. 320if_no_head(Goal, _) :- 321 call(Goal). 322 323reply_file(Out, _File, Header, head) :- 324 !, 325 send_reply_header(Out, Header). 326reply_file(Out, File, Header, _) :- 327 setup_call_cleanup( 328 open(File, read, In, [type(binary)]), 329 copy_stream(Out, In, Header, 0, end), 330 close(In)). 331 332reply_file_range(Out, _File, Header, _Range, head) :- 333 !, 334 send_reply_header(Out, Header). 335reply_file_range(Out, File, Header, bytes(From, To), _) :- 336 setup_call_cleanup( 337 open(File, read, In, [type(binary)]), 338 copy_stream(Out, In, Header, From, To), 339 close(In)). 340 341copy_stream(Out, _, Header, head, _, _) :- 342 !, 343 send_reply_header(Out, Header). 344copy_stream(Out, In, Header, _, From, To) :- 345 copy_stream(Out, In, Header, From, To). 346 347copy_stream(Out, In, Header, From, To) :- 348 ( From == 0 349 -> true 350 ; seek(In, From, bof, _) 351 ), 352 peek_byte(In, _), 353 send_reply_header(Out, Header), 354 ( To == end 355 -> copy_stream_data(In, Out) 356 ; Len is To - From, 357 copy_stream_data(In, Out, Len) 358 ).
Status can be one of the following:
basic(Realm)digest(Digest)authorise(basic(Realm)). Deprecated.392http_status_reply(Status, Out, Options) :- 393 _{header:HdrExtra, context:Context, code:Code, method:Method} :< Options, 394 http_status_reply(Status, Out, HdrExtra, Context, [method(Method)], Code). 395 396http_status_reply(Status, Out, HdrExtra, Code) :- 397 http_status_reply(Status, Out, HdrExtra, [], Code). 398 399http_status_reply(Status, Out, HdrExtra, Context, Code) :- 400 http_status_reply(Status, Out, HdrExtra, Context, [method(get)], Code). 401 402http_status_reply(Status, Out, HdrExtra, Context, Request, Code) :- 403 option(method(Method), Request, get), 404 parsed_accept(Request, Accept), 405 status_reply_flush(Status, Out, 406 _{ context: Context, 407 method: Method, 408 code: Code, 409 accept: Accept, 410 header: HdrExtra 411 }). 412 413parsed_accept(Request, Accept) :- 414 memberchk(accept(Accept0), Request), 415 http_parse_header_value(accept, Accept0, Accept1), 416 !, 417 Accept = Accept1. 418parsed_accept(_, [ media(text/html, [], 0.1, []), 419 media(_, [], 0.01, []) 420 ]). 421 422status_reply_flush(Status, Out, Options) :- 423 status_reply(Status, Out, Options), 424 !, 425 flush_output(Out).
438% Replies without content 439status_reply(no_content, Out, Options) :- 440 !, 441 phrase(reply_header(status(no_content), Options), Header), 442 send_reply_header(Out, Header). 443status_reply(switching_protocols(_Goal,SwitchOptions), Out, Options) :- 444 !, 445 ( option(headers(Extra1), SwitchOptions) 446 -> true 447 ; option(header(Extra1), SwitchOptions, []) 448 ), 449 http_join_headers(Options.header, Extra1, HdrExtra), 450 phrase(reply_header(status(switching_protocols), 451 Options.put(header,HdrExtra)), Header), 452 send_reply_header(Out, Header). 453status_reply(authorise(basic, ''), Out, Options) :- 454 !, 455 status_reply(authorise(basic), Out, Options). 456status_reply(authorise(basic, Realm), Out, Options) :- 457 !, 458 status_reply(authorise(basic(Realm)), Out, Options). 459status_reply(not_modified, Out, Options) :- 460 !, 461 phrase(reply_header(status(not_modified), Options), Header), 462 send_reply_header(Out, Header). 463% aliases (compatibility) 464status_reply(busy, Out, Options) :- 465 status_reply(service_unavailable(busy), Out, Options). 466status_reply(unavailable(Why), Out, Options) :- 467 status_reply(service_unavailable(Why), Out, Options). 468status_reply(resource_error(Why), Out, Options) :- 469 status_reply(service_unavailable(Why), Out, Options). 470% replies with content 471status_reply(Status, Out, Options) :- 472 status_has_content(Status), 473 status_page_hook(Status, Reply, Options), 474 serialize_body(Reply, Body), 475 Status =.. List, 476 append(List, [Body], ExList), 477 ExStatus =.. ExList, 478 phrase(reply_header(ExStatus, Options), Header), 479 send_reply_header(Out, Header), 480 reply_status_body(Out, Body, Options).
487status_has_content(created(_Location)). 488status_has_content(moved(_To)). 489status_has_content(moved_temporary(_To)). 490status_has_content(gone(_URL)). 491status_has_content(see_other(_To)). 492status_has_content(bad_request(_ErrorTerm)). 493status_has_content(authorise(_Method)). 494status_has_content(forbidden(_URL)). 495status_has_content(not_found(_URL)). 496status_has_content(method_not_allowed(_Method, _URL)). 497status_has_content(not_acceptable(_Why)). 498status_has_content(server_error(_ErrorTerm)). 499status_has_content(service_unavailable(_Why)).
510serialize_body(Reply, Body) :- 511 http:serialize_reply(Reply, Body), 512 !. 513serialize_body(html_tokens(Tokens), body(text/html, utf8, Content)) :- 514 !, 515 with_output_to(string(Content), print_html(Tokens)). 516serialize_body(Reply, Reply) :- 517 Reply = body(_,_,_), 518 !. 519serialize_body(Reply, _) :- 520 domain_error(http_reply_body, Reply). 521 522reply_status_body(_, _, Options) :- 523 Options.method == head, 524 !. 525reply_status_body(Out, body(_Type, Encoding, Content), _Options) :- 526 ( Encoding == octet 527 -> format(Out, '~s', [Content]) 528 ; setup_call_cleanup( 529 set_stream(Out, encoding(Encoding)), 530 format(Out, '~s', [Content]), 531 set_stream(Out, encoding(octet))) 532 ).
559status_page_hook(Term, Reply, Options) :- 560 Context = Options.context, 561 functor(Term, Name, _), 562 status_number_fact(Name, Code), 563 ( Options.code = Code, 564 http:status_reply(Term, Reply, Options) 565 ; http:status_page(Term, Context, HTML), 566 Reply = html_tokens(HTML) 567 ; http:status_page(Code, Context, HTML), % deprecated 568 Reply = html_tokens(HTML) 569 ), 570 !. 571status_page_hook(created(Location), html_tokens(HTML), _Options) :- 572 phrase(page([ title('201 Created') 573 ], 574 [ h1('Created'), 575 p(['The document was created ', 576 a(href(Location), ' Here') 577 ]), 578 \address 579 ]), 580 HTML). 581status_page_hook(moved(To), html_tokens(HTML), _Options) :- 582 phrase(page([ title('301 Moved Permanently') 583 ], 584 [ h1('Moved Permanently'), 585 p(['The document has moved ', 586 a(href(To), ' Here') 587 ]), 588 \address 589 ]), 590 HTML). 591status_page_hook(moved_temporary(To), html_tokens(HTML), _Options) :- 592 phrase(page([ title('302 Moved Temporary') 593 ], 594 [ h1('Moved Temporary'), 595 p(['The document is currently ', 596 a(href(To), ' Here') 597 ]), 598 \address 599 ]), 600 HTML). 601status_page_hook(gone(URL), html_tokens(HTML), _Options) :- 602 phrase(page([ title('410 Resource Gone') 603 ], 604 [ h1('Resource Gone'), 605 p(['The document has been removed ', 606 a(href(URL), ' from here') 607 ]), 608 \address 609 ]), 610 HTML). 611status_page_hook(see_other(To), html_tokens(HTML), _Options) :- 612 phrase(page([ title('303 See Other') 613 ], 614 [ h1('See Other'), 615 p(['See other document ', 616 a(href(To), ' Here') 617 ]), 618 \address 619 ]), 620 HTML). 621status_page_hook(bad_request(ErrorTerm), html_tokens(HTML), _Options) :- 622 '$messages':translate_message(ErrorTerm, Lines, []), 623 phrase(page([ title('400 Bad Request') 624 ], 625 [ h1('Bad Request'), 626 p(\html_message_lines(Lines)), 627 \address 628 ]), 629 HTML). 630status_page_hook(authorise(_Method), html_tokens(HTML), _Options):- 631 phrase(page([ title('401 Authorization Required') 632 ], 633 [ h1('Authorization Required'), 634 p(['This server could not verify that you ', 635 'are authorized to access the document ', 636 'requested. Either you supplied the wrong ', 637 'credentials (e.g., bad password), or your ', 638 'browser doesn\'t understand how to supply ', 639 'the credentials required.' 640 ]), 641 \address 642 ]), 643 HTML). 644status_page_hook(forbidden(URL), html_tokens(HTML), _Options) :- 645 phrase(page([ title('403 Forbidden') 646 ], 647 [ h1('Forbidden'), 648 p(['You don\'t have permission to access ', URL, 649 ' on this server' 650 ]), 651 \address 652 ]), 653 HTML). 654status_page_hook(not_found(URL), html_tokens(HTML), _Options) :- 655 phrase(page([ title('404 Not Found') 656 ], 657 [ h1('Not Found'), 658 p(['The requested URL ', tt(URL), 659 ' was not found on this server' 660 ]), 661 \address 662 ]), 663 HTML). 664status_page_hook(method_not_allowed(Method,URL), html_tokens(HTML), _Options) :- 665 upcase_atom(Method, UMethod), 666 phrase(page([ title('405 Method not allowed') 667 ], 668 [ h1('Method not allowed'), 669 p(['The requested URL ', tt(URL), 670 ' does not support method ', tt(UMethod), '.' 671 ]), 672 \address 673 ]), 674 HTML). 675status_page_hook(not_acceptable(WhyHTML), html_tokens(HTML), _Options) :- 676 phrase(page([ title('406 Not Acceptable') 677 ], 678 [ h1('Not Acceptable'), 679 WhyHTML, 680 \address 681 ]), 682 HTML). 683status_page_hook(server_error(ErrorTerm), html_tokens(HTML), _Options) :- 684 '$messages':translate_message(ErrorTerm, Lines, []), 685 phrase(page([ title('500 Internal server error') 686 ], 687 [ h1('Internal server error'), 688 p(\html_message_lines(Lines)), 689 \address 690 ]), 691 HTML). 692status_page_hook(service_unavailable(Why), html_tokens(HTML), _Options) :- 693 phrase(page([ title('503 Service Unavailable') 694 ], 695 [ h1('Service Unavailable'), 696 \unavailable(Why), 697 \address 698 ]), 699 HTML). 700 (busy) --> 702 html(p(['The server is temporarily out of resources, ', 703 'please try again later'])). 704unavailable(error(Formal,Context)) --> 705 { '$messages':translate_message(error(Formal,Context), Lines, []) }, 706 html_message_lines(Lines). 707unavailable(HTML) --> 708 html(HTML). 709 710html_message_lines([]) --> 711 []. 712html_message_lines([nl|T]) --> 713 !, 714 html([br([])]), 715 html_message_lines(T). 716html_message_lines([flush]) --> 717 []. 718html_message_lines([ansi(_Style,Fmt,Args)|T]) --> 719 !, 720 { format(string(S), Fmt, Args) 721 }, 722 html([S]), 723 html_message_lines(T). 724html_message_lines([url(Pos)|T]) --> 725 !, 726 msg_url(Pos), 727 html_message_lines(T). 728html_message_lines([url(URL, Label)|T]) --> 729 !, 730 html(a(href(URL), Label)), 731 html_message_lines(T). 732html_message_lines([Fmt-Args|T]) --> 733 !, 734 { format(string(S), Fmt, Args) 735 }, 736 html([S]), 737 html_message_lines(T). 738html_message_lines([Fmt|T]) --> 739 !, 740 { format(string(S), Fmt, []) 741 }, 742 html([S]), 743 html_message_lines(T). 744 745msg_url(File:Line:Pos) --> 746 !, 747 html([File, :, Line, :, Pos]). 748msg_url(File:Line) --> 749 !, 750 html([File, :, Line]). 751msg_url(File) --> 752 html([File]).
759http_join_headers([], H, H). 760http_join_headers([H|T], Hdr0, Hdr) :- 761 functor(H, N, A), 762 functor(H2, N, A), 763 member(H2, Hdr0), 764 !, 765 http_join_headers(T, Hdr0, Hdr). 766http_join_headers([H|T], Hdr0, [H|Hdr]) :- 767 http_join_headers(T, Hdr0, Hdr).
779http_update_encoding(Header0, utf8, [content_type(Type)|Header]) :- 780 select(content_type(Type0), Header0, Header), 781 sub_atom(Type0, 0, _, _, 'text/'), 782 !, 783 ( sub_atom(Type0, S, _, _, ';') 784 -> sub_atom(Type0, 0, S, _, B) 785 ; B = Type0 786 ), 787 atom_concat(B, '; charset=UTF-8', Type). 788http_update_encoding(Header, Encoding, Header) :- 789 memberchk(content_type(Type), Header), 790 ( sub_atom_icasechk(Type, _, 'utf-8') 791 -> Encoding = utf8 792 ; http:mime_type_encoding(Type, Encoding) 793 -> true 794 ; mime_type_encoding(Type, Encoding) 795 ). 796http_update_encoding(Header, octet, Header).
803mime_type_encoding('application/json', utf8). 804mime_type_encoding('application/jsonrequest', utf8). 805mime_type_encoding('application/x-prolog', utf8). 806mime_type_encoding('application/n-quads', utf8). 807mime_type_encoding('application/n-triples', utf8). 808mime_type_encoding('application/sparql-query', utf8). 809mime_type_encoding('application/trig', utf8). 810mime_type_encoding('application/sparql-results+json', utf8). 811mime_type_encoding('application/sparql-results+xml', utf8).
format('Content-type: <MIME type>~n'). This hook is called before
mime_type_encoding/2. This default defines utf8 for JSON and
Turtle derived application/ MIME types.827http_update_connection(CgiHeader, Request, Connect, 828 [connection(Connect)|Rest]) :- 829 select(connection(CgiConn), CgiHeader, Rest), 830 !, 831 connection(Request, ReqConnection), 832 join_connection(ReqConnection, CgiConn, Connect). 833http_update_connection(CgiHeader, Request, Connect, 834 [connection(Connect)|CgiHeader]) :- 835 connection(Request, Connect). 836 837join_connection(Keep1, Keep2, Connection) :- 838 ( downcase_atom(Keep1, 'keep-alive'), 839 downcase_atom(Keep2, 'keep-alive') 840 -> Connection = 'Keep-Alive' 841 ; Connection = close 842 ).
849connection(Header, Close) :-
850 ( memberchk(connection(Connection), Header)
851 -> Close = Connection
852 ; memberchk(http_version(1-X), Header),
853 X >= 1
854 -> Close = 'Keep-Alive'
855 ; Close = close
856 ).never, even explitic requests are
ignored. If on_request, chunked encoding is used if requested
through the CGI header and allowed by the client. If
if_possible, chunked encoding is used whenever the client
allows for it, which is interpreted as the client supporting
HTTP 1.1 or higher.
Chunked encoding is more space efficient and allows the client to start processing partial results. The drawback is that errors lead to incomplete pages instead of a nicely formatted complete page.
875http_update_transfer(Request, CgiHeader, Transfer, Header) :- 876 setting(http:chunked_transfer, When), 877 http_update_transfer(When, Request, CgiHeader, Transfer, Header). 878 879http_update_transfer(never, _, CgiHeader, none, Header) :- 880 !, 881 delete(CgiHeader, transfer_encoding(_), Header). 882http_update_transfer(_, _, CgiHeader, none, Header) :- 883 memberchk(location(_), CgiHeader), 884 !, 885 delete(CgiHeader, transfer_encoding(_), Header). 886http_update_transfer(_, Request, CgiHeader, Transfer, Header) :- 887 select(transfer_encoding(CgiTransfer), CgiHeader, Rest), 888 !, 889 transfer(Request, ReqConnection), 890 join_transfer(ReqConnection, CgiTransfer, Transfer), 891 ( Transfer == none 892 -> Header = Rest 893 ; Header = [transfer_encoding(Transfer)|Rest] 894 ). 895http_update_transfer(if_possible, Request, CgiHeader, Transfer, Header) :- 896 transfer(Request, Transfer), 897 Transfer \== none, 898 !, 899 Header = [transfer_encoding(Transfer)|CgiHeader]. 900http_update_transfer(_, _, CgiHeader, none, CgiHeader). 901 902join_transfer(chunked, chunked, chunked) :- !. 903join_transfer(_, _, none).
910transfer(Header, Transfer) :-
911 ( memberchk(transfer_encoding(Transfer0), Header)
912 -> Transfer = Transfer0
913 ; memberchk(http_version(1-X), Header),
914 X >= 1
915 -> Transfer = chunked
916 ; Transfer = none
917 ).926content_length_in_encoding(Enc, Stream, Bytes) :- 927 stream_property(Stream, position(Here)), 928 setup_call_cleanup( 929 open_null_stream(Out), 930 ( set_stream(Out, encoding(Enc)), 931 catch(copy_stream_data(Stream, Out), _, fail), 932 flush_output(Out), 933 byte_count(Out, Bytes) 934 ), 935 ( close(Out, [force(true)]), 936 set_stream_position(Stream, Here) 937 )). 938 939 940 /******************************* 941 * POST SUPPORT * 942 *******************************/
http_client.pl to send the
POST data to the server. Data is one of:
html(+Tokens)
Result of html//1 from html_write.pljson(+Term)
Posting a JSON query and processing the JSON reply (or any other
reply understood by http_read_data/3) is simple as
http_post(URL, json(Term), Reply, []), where Term is a JSON
term as described in json.pl and reply is of the same format if
the server replies with JSON, when using module :-
use_module(library(http/http_json)). Note that the module is
used in both http server and http client, see
library(http/http_json).xml(+Term)
Post the result of xml_write/3 using the Mime-type
text/xmlxml(+Type, +Term)
Post the result of xml_write/3 using the given Mime-type
and an empty option list to xml_write/3.xml(+Type, +Term, +Options)
Post the result of xml_write/3 using the given Mime-type
and option list for xml_write/3.file(+File)
Send contents of a file. Mime-type is determined by
file_mime_type/2.file(+Type, +File)
Send file with content of indicated mime-type.memory_file(+Type, +Handle)
Similar to file(+Type, +File), but using a memory file
instead of a real file. See new_memory_file/1.codes(+Codes)
As codes(text/plain, Codes).codes(+Type, +Codes)
Send Codes using the indicated MIME-type.bytes(+Type, +Bytes)
Send Bytes using the indicated MIME-type. Bytes is either a
string of character codes 0..255 or list of integers in the
range 0..255. Out-of-bound codes result in a representation
error exception.atom(+Atom)
As atom(text/plain, Atom).atom(+Type, +Atom)
Send Atom using the indicated MIME-type.string(+String)string(+Type, +String)
Similar to atom(Atom) and atom(Type,Atom), accepting a SWI-Prolog
string.cgi_stream(+Stream, +Len) Read the input from Stream which,
like CGI data starts with a partial HTTP header. The fields of
this header are merged with the provided HdrExtra fields. The
first Len characters of Stream are used.form(+ListOfParameter)
Send data of the MIME type application/x-www-form-urlencoded as
produced by browsers issuing a POST request from an HTML form.
ListOfParameter is a list of Name=Value or Name(Value).form_data(+ListOfData)
Send data of the MIME type multipart/form-data as produced
by browsers issuing a POST request from an HTML form using
enctype multipart/form-data. ListOfData is the same as for
the List alternative described below. Below is an example.
Repository, etc. are atoms providing the value, while the last
argument provides a value from a file.
...,
http_post([ protocol(http),
host(Host),
port(Port),
path(ActionPath)
],
form_data([ repository = Repository,
dataFormat = DataFormat,
baseURI = BaseURI,
verifyData = Verify,
data = file(File)
]),
_Reply,
[]),
...,
1050http_post_data(Data, Out, HdrExtra) :- 1051 http:post_data_hook(Data, Out, HdrExtra), 1052 !. 1053http_post_data(html(HTML), Out, HdrExtra) :- 1054 !, 1055 phrase(post_header(html(HTML), HdrExtra), Header), 1056 send_request_header(Out, Header), 1057 print_html(Out, HTML). 1058http_post_data(xml(XML), Out, HdrExtra) :- 1059 !, 1060 http_post_data(xml(text/xml, XML, []), Out, HdrExtra). 1061http_post_data(xml(Type, XML), Out, HdrExtra) :- 1062 !, 1063 http_post_data(xml(Type, XML, []), Out, HdrExtra). 1064http_post_data(xml(Type, XML, Options), Out, HdrExtra) :- 1065 !, 1066 setup_call_cleanup( 1067 new_memory_file(MemFile), 1068 ( setup_call_cleanup( 1069 open_memory_file(MemFile, write, MemOut), 1070 xml_write(MemOut, XML, Options), 1071 close(MemOut)), 1072 http_post_data(memory_file(Type, MemFile), Out, HdrExtra) 1073 ), 1074 free_memory_file(MemFile)). 1075http_post_data(file(File), Out, HdrExtra) :- 1076 !, 1077 ( file_mime_type(File, Type) 1078 -> true 1079 ; Type = text/plain 1080 ), 1081 http_post_data(file(Type, File), Out, HdrExtra). 1082http_post_data(file(Type, File), Out, HdrExtra) :- 1083 !, 1084 phrase(post_header(file(Type, File), HdrExtra), Header), 1085 send_request_header(Out, Header), 1086 setup_call_cleanup( 1087 open(File, read, In, [type(binary)]), 1088 copy_stream_data(In, Out), 1089 close(In)). 1090http_post_data(memory_file(Type, Handle), Out, HdrExtra) :- 1091 !, 1092 phrase(post_header(memory_file(Type, Handle), HdrExtra), Header), 1093 send_request_header(Out, Header), 1094 setup_call_cleanup( 1095 open_memory_file(Handle, read, In, [encoding(octet)]), 1096 copy_stream_data(In, Out), 1097 close(In)). 1098http_post_data(codes(Codes), Out, HdrExtra) :- 1099 !, 1100 http_post_data(codes(text/plain, Codes), Out, HdrExtra). 1101http_post_data(codes(Type, Codes), Out, HdrExtra) :- 1102 !, 1103 phrase(post_header(codes(Type, Codes), HdrExtra), Header), 1104 send_request_header(Out, Header), 1105 setup_call_cleanup( 1106 set_stream(Out, encoding(utf8)), 1107 format(Out, '~s', [Codes]), 1108 set_stream(Out, encoding(octet))). 1109http_post_data(bytes(Type, Bytes), Out, HdrExtra) :- 1110 !, 1111 phrase(post_header(bytes(Type, Bytes), HdrExtra), Header), 1112 send_request_header(Out, Header), 1113 format(Out, '~s', [Bytes]). 1114http_post_data(atom(Atom), Out, HdrExtra) :- 1115 !, 1116 http_post_data(atom(text/plain, Atom), Out, HdrExtra). 1117http_post_data(atom(Type, Atom), Out, HdrExtra) :- 1118 !, 1119 phrase(post_header(atom(Type, Atom), HdrExtra), Header), 1120 send_request_header(Out, Header), 1121 setup_call_cleanup( 1122 set_stream(Out, encoding(utf8)), 1123 write(Out, Atom), 1124 set_stream(Out, encoding(octet))). 1125http_post_data(string(String), Out, HdrExtra) :- 1126 !, 1127 http_post_data(atom(text/plain, String), Out, HdrExtra). 1128http_post_data(string(Type, String), Out, HdrExtra) :- 1129 !, 1130 phrase(post_header(string(Type, String), HdrExtra), Header), 1131 send_request_header(Out, Header), 1132 setup_call_cleanup( 1133 set_stream(Out, encoding(utf8)), 1134 write(Out, String), 1135 set_stream(Out, encoding(octet))). 1136http_post_data(cgi_stream(In, _Len), Out, HdrExtra) :- 1137 !, 1138 debug(obsolete, 'Obsolete 2nd argument in cgi_stream(In,Len)', []), 1139 http_post_data(cgi_stream(In), Out, HdrExtra). 1140http_post_data(cgi_stream(In), Out, HdrExtra) :- 1141 !, 1142 http_read_header(In, Header0), 1143 http_update_encoding(Header0, Encoding, Header), 1144 content_length_in_encoding(Encoding, In, Size), 1145 http_join_headers(HdrExtra, Header, Hdr2), 1146 phrase(post_header(cgi_data(Size), Hdr2), HeaderText), 1147 send_request_header(Out, HeaderText), 1148 setup_call_cleanup( 1149 set_stream(Out, encoding(Encoding)), 1150 copy_stream_data(In, Out), 1151 set_stream(Out, encoding(octet))). 1152http_post_data(form(Fields), Out, HdrExtra) :- 1153 !, 1154 parse_url_search(Codes, Fields), 1155 length(Codes, Size), 1156 http_join_headers(HdrExtra, 1157 [ content_type('application/x-www-form-urlencoded') 1158 ], Header), 1159 phrase(post_header(cgi_data(Size), Header), HeaderChars), 1160 send_request_header(Out, HeaderChars), 1161 format(Out, '~s', [Codes]). 1162http_post_data(form_data(Data), Out, HdrExtra) :- 1163 !, 1164 setup_call_cleanup( 1165 new_memory_file(MemFile), 1166 ( setup_call_cleanup( 1167 open_memory_file(MemFile, write, MimeOut), 1168 mime_pack(Data, MimeOut, Boundary), 1169 close(MimeOut)), 1170 size_memory_file(MemFile, Size, octet), 1171 format(string(ContentType), 1172 'multipart/form-data; boundary=~w', [Boundary]), 1173 http_join_headers(HdrExtra, 1174 [ mime_version('1.0'), 1175 content_type(ContentType) 1176 ], Header), 1177 phrase(post_header(cgi_data(Size), Header), HeaderChars), 1178 send_request_header(Out, HeaderChars), 1179 setup_call_cleanup( 1180 open_memory_file(MemFile, read, In, [encoding(octet)]), 1181 copy_stream_data(In, Out), 1182 close(In)) 1183 ), 1184 free_memory_file(MemFile)). 1185http_post_data(List, Out, HdrExtra) :- % multipart-mixed 1186 is_list(List), 1187 !, 1188 setup_call_cleanup( 1189 new_memory_file(MemFile), 1190 ( setup_call_cleanup( 1191 open_memory_file(MemFile, write, MimeOut), 1192 mime_pack(List, MimeOut, Boundary), 1193 close(MimeOut)), 1194 size_memory_file(MemFile, Size, octet), 1195 format(string(ContentType), 1196 'multipart/mixed; boundary=~w', [Boundary]), 1197 http_join_headers(HdrExtra, 1198 [ mime_version('1.0'), 1199 content_type(ContentType) 1200 ], Header), 1201 phrase(post_header(cgi_data(Size), Header), HeaderChars), 1202 send_request_header(Out, HeaderChars), 1203 setup_call_cleanup( 1204 open_memory_file(MemFile, read, In, [encoding(octet)]), 1205 copy_stream_data(In, Out), 1206 close(In)) 1207 ), 1208 free_memory_file(MemFile)).
1215post_header(html(Tokens), HdrExtra) --> 1216 header_fields(HdrExtra, Len), 1217 content_length(html(Tokens), Len), 1218 content_type(text/html), 1219 "\r\n". 1220post_header(file(Type, File), HdrExtra) --> 1221 header_fields(HdrExtra, Len), 1222 content_length(file(File), Len), 1223 content_type(Type), 1224 "\r\n". 1225post_header(memory_file(Type, File), HdrExtra) --> 1226 header_fields(HdrExtra, Len), 1227 content_length(memory_file(File), Len), 1228 content_type(Type), 1229 "\r\n". 1230post_header(cgi_data(Size), HdrExtra) --> 1231 header_fields(HdrExtra, Len), 1232 content_length(Size, Len), 1233 "\r\n". 1234post_header(codes(Type, Codes), HdrExtra) --> 1235 header_fields(HdrExtra, Len), 1236 content_length(codes(Codes, utf8), Len), 1237 content_type(Type, utf8), 1238 "\r\n". 1239post_header(bytes(Type, Bytes), HdrExtra) --> 1240 header_fields(HdrExtra, Len), 1241 content_length(bytes(Bytes), Len), 1242 content_type(Type), 1243 "\r\n". 1244post_header(atom(Type, Atom), HdrExtra) --> 1245 header_fields(HdrExtra, Len), 1246 content_length(atom(Atom, utf8), Len), 1247 content_type(Type, utf8), 1248 "\r\n". 1249post_header(string(Type, String), HdrExtra) --> 1250 header_fields(HdrExtra, Len), 1251 content_length(string(String, utf8), Len), 1252 content_type(Type, utf8), 1253 "\r\n". 1254 1255 1256 /******************************* 1257 * OUTPUT HEADER DCG * 1258 *******************************/
1265http_reply_header(Out, What, HdrExtra) :-
1266 phrase(reply_header(What, HdrExtra, _Code), String),
1267 !,
1268 send_reply_header(Out, String).created(+URL, +HTMLTokens)moved(+URL, +HTMLTokens)moved_temporary(+URL, +HTMLTokens)see_other(+URL, +HTMLTokens)status(+Status)status(+Status, +HTMLTokens)authorise(+Method, +Realm, +Tokens)authorise(+Method, +Tokens)not_found(+URL, +HTMLTokens)server_error(+Error, +Tokens)resource_error(+Error, +Tokens)service_unavailable(+Why, +Tokens)1292reply_header(Data, Dict) --> 1293 { _{header:HdrExtra, code:Code} :< Dict }, 1294 reply_header(Data, HdrExtra, Code). 1295 1296reply_header(string(String), HdrExtra, Code) --> 1297 reply_header(string(text/plain, String), HdrExtra, Code). 1298reply_header(string(Type, String), HdrExtra, Code) --> 1299 vstatus(ok, Code, HdrExtra), 1300 date(now), 1301 header_fields(HdrExtra, CLen), 1302 content_length(codes(String, utf8), CLen), 1303 content_type(Type, utf8), 1304 "\r\n". 1305reply_header(bytes(Type, Bytes), HdrExtra, Code) --> 1306 vstatus(ok, Code, HdrExtra), 1307 date(now), 1308 header_fields(HdrExtra, CLen), 1309 content_length(bytes(Bytes), CLen), 1310 content_type(Type), 1311 "\r\n". 1312reply_header(html(Tokens), HdrExtra, Code) --> 1313 vstatus(ok, Code, HdrExtra), 1314 date(now), 1315 header_fields(HdrExtra, CLen), 1316 content_length(html(Tokens), CLen), 1317 content_type(text/html), 1318 "\r\n". 1319reply_header(file(Type, File), HdrExtra, Code) --> 1320 vstatus(ok, Code, HdrExtra), 1321 date(now), 1322 modified(file(File)), 1323 header_fields(HdrExtra, CLen), 1324 content_length(file(File), CLen), 1325 content_type(Type), 1326 "\r\n". 1327reply_header(gzip_file(Type, File), HdrExtra, Code) --> 1328 vstatus(ok, Code, HdrExtra), 1329 date(now), 1330 modified(file(File)), 1331 header_fields(HdrExtra, CLen), 1332 content_length(file(File), CLen), 1333 content_type(Type), 1334 content_encoding(gzip), 1335 "\r\n". 1336reply_header(file(Type, File, Range), HdrExtra, Code) --> 1337 vstatus(partial_content, Code, HdrExtra), 1338 date(now), 1339 modified(file(File)), 1340 header_fields(HdrExtra, CLen), 1341 content_length(file(File, Range), CLen), 1342 content_type(Type), 1343 "\r\n". 1344reply_header(tmp_file(Type, File), HdrExtra, Code) --> 1345 vstatus(ok, Code, HdrExtra), 1346 date(now), 1347 header_fields(HdrExtra, CLen), 1348 content_length(file(File), CLen), 1349 content_type(Type), 1350 "\r\n". 1351reply_header(cgi_data(Size), HdrExtra, Code) --> 1352 vstatus(ok, Code, HdrExtra), 1353 date(now), 1354 header_fields(HdrExtra, CLen), 1355 content_length(Size, CLen), 1356 "\r\n". 1357reply_header(chunked_data, HdrExtra, Code) --> 1358 vstatus(ok, Code, HdrExtra), 1359 date(now), 1360 header_fields(HdrExtra, _), 1361 ( {memberchk(transfer_encoding(_), HdrExtra)} 1362 -> "" 1363 ; transfer_encoding(chunked) 1364 ), 1365 "\r\n". 1366% non-200 replies without a body (e.g., 1xx, 204, 304) 1367reply_header(status(Status), HdrExtra, Code) --> 1368 vstatus(Status, Code), 1369 header_fields(HdrExtra, Clen), 1370 { Clen = 0 }, 1371 "\r\n". 1372% non-200 replies with a body 1373reply_header(Data, HdrExtra, Code) --> 1374 { status_reply_headers(Data, 1375 body(Type, Encoding, Content), 1376 ReplyHeaders), 1377 http_join_headers(ReplyHeaders, HdrExtra, Headers), 1378 functor(Data, CodeName, _) 1379 }, 1380 vstatus(CodeName, Code, Headers), 1381 date(now), 1382 header_fields(Headers, CLen), 1383 content_length(codes(Content, Encoding), CLen), 1384 content_type(Type, Encoding), 1385 "\r\n". 1386 1387status_reply_headers(created(Location, Body), Body, 1388 [ location(Location) ]). 1389status_reply_headers(moved(To, Body), Body, 1390 [ location(To) ]). 1391status_reply_headers(moved_temporary(To, Body), Body, 1392 [ location(To) ]). 1393status_reply_headers(gone(_URL, Body), Body, []). 1394status_reply_headers(see_other(To, Body), Body, 1395 [ location(To) ]). 1396status_reply_headers(authorise(Method, Body), Body, 1397 [ www_authenticate(Method) ]). 1398status_reply_headers(not_found(_URL, Body), Body, []). 1399status_reply_headers(forbidden(_URL, Body), Body, []). 1400status_reply_headers(method_not_allowed(_Method, _URL, Body), Body, []). 1401status_reply_headers(server_error(_Error, Body), Body, []). 1402status_reply_headers(service_unavailable(_Why, Body), Body, []). 1403status_reply_headers(not_acceptable(_Why, Body), Body, []). 1404status_reply_headers(bad_request(_Error, Body), Body, []).
1412vstatus(_Status, Code, HdrExtra) --> 1413 {memberchk(status(Code), HdrExtra)}, 1414 !, 1415 vstatus(_NewStatus, Code). 1416vstatus(Status, Code, _) --> 1417 vstatus(Status, Code). 1418 1419vstatus(Status, Code) --> 1420 "HTTP/1.1 ", 1421 status_number(Status, Code), 1422 " ", 1423 status_comment(Status), 1424 "\r\n".
1433status_number(Status, Code) --> 1434 { var(Status) }, 1435 !, 1436 integer(Code), 1437 { status_number(Status, Code) }, 1438 !. 1439status_number(Status, Code) --> 1440 { status_number(Status, Code) }, 1441 integer(Code).
1455% Unrecognized status codes that are within a defined code class. 1456% RFC 7231 states: 1457% "[...] a client MUST understand the class of any status code, 1458% as indicated by the first digit, and treat an unrecognized status code 1459% as being equivalent to the `x00` status code of that class [...] 1460% " 1461% @see http://tools.ietf.org/html/rfc7231#section-6 1462 1463status_number(Status, Code) :- 1464 nonvar(Status), 1465 !, 1466 status_number_fact(Status, Code). 1467status_number(Status, Code) :- 1468 nonvar(Code), 1469 !, 1470 ( between(100, 599, Code) 1471 -> ( status_number_fact(Status, Code) 1472 -> true 1473 ; ClassCode is Code // 100 * 100, 1474 status_number_fact(Status, ClassCode) 1475 ) 1476 ; domain_error(http_code, Code) 1477 ). 1478 1479status_number_fact(continue, 100). 1480status_number_fact(switching_protocols, 101). 1481status_number_fact(ok, 200). 1482status_number_fact(created, 201). 1483status_number_fact(accepted, 202). 1484status_number_fact(non_authoritative_info, 203). 1485status_number_fact(no_content, 204). 1486status_number_fact(reset_content, 205). 1487status_number_fact(partial_content, 206). 1488status_number_fact(multiple_choices, 300). 1489status_number_fact(moved, 301). 1490status_number_fact(moved_temporary, 302). 1491status_number_fact(see_other, 303). 1492status_number_fact(not_modified, 304). 1493status_number_fact(use_proxy, 305). 1494status_number_fact(unused, 306). 1495status_number_fact(temporary_redirect, 307). 1496status_number_fact(bad_request, 400). 1497status_number_fact(authorise, 401). 1498status_number_fact(payment_required, 402). 1499status_number_fact(forbidden, 403). 1500status_number_fact(not_found, 404). 1501status_number_fact(method_not_allowed, 405). 1502status_number_fact(not_acceptable, 406). 1503status_number_fact(request_timeout, 408). 1504status_number_fact(conflict, 409). 1505status_number_fact(gone, 410). 1506status_number_fact(length_required, 411). 1507status_number_fact(payload_too_large, 413). 1508status_number_fact(uri_too_long, 414). 1509status_number_fact(unsupported_media_type, 415). 1510status_number_fact(expectation_failed, 417). 1511status_number_fact(upgrade_required, 426). 1512status_number_fact(server_error, 500). 1513status_number_fact(not_implemented, 501). 1514status_number_fact(bad_gateway, 502). 1515status_number_fact(service_unavailable, 503). 1516status_number_fact(gateway_timeout, 504). 1517status_number_fact(http_version_not_supported, 505).
1524status_comment(continue) --> 1525 "Continue". 1526status_comment(switching_protocols) --> 1527 "Switching Protocols". 1528status_comment(ok) --> 1529 "OK". 1530status_comment(created) --> 1531 "Created". 1532status_comment(accepted) --> 1533 "Accepted". 1534status_comment(non_authoritative_info) --> 1535 "Non-Authoritative Information". 1536status_comment(no_content) --> 1537 "No Content". 1538status_comment(reset_content) --> 1539 "Reset Content". 1540status_comment(created) --> 1541 "Created". 1542status_comment(partial_content) --> 1543 "Partial content". 1544status_comment(multiple_choices) --> 1545 "Multiple Choices". 1546status_comment(moved) --> 1547 "Moved Permanently". 1548status_comment(moved_temporary) --> 1549 "Moved Temporary". 1550status_comment(see_other) --> 1551 "See Other". 1552status_comment(not_modified) --> 1553 "Not Modified". 1554status_comment(use_proxy) --> 1555 "Use Proxy". 1556status_comment(unused) --> 1557 "Unused". 1558status_comment(temporary_redirect) --> 1559 "Temporary Redirect". 1560status_comment(bad_request) --> 1561 "Bad Request". 1562status_comment(authorise) --> 1563 "Authorization Required". 1564status_comment(payment_required) --> 1565 "Payment Required". 1566status_comment(forbidden) --> 1567 "Forbidden". 1568status_comment(not_found) --> 1569 "Not Found". 1570status_comment(method_not_allowed) --> 1571 "Method Not Allowed". 1572status_comment(not_acceptable) --> 1573 "Not Acceptable". 1574status_comment(request_timeout) --> 1575 "Request Timeout". 1576status_comment(conflict) --> 1577 "Conflict". 1578status_comment(gone) --> 1579 "Gone". 1580status_comment(length_required) --> 1581 "Length Required". 1582status_comment(payload_too_large) --> 1583 "Payload Too Large". 1584status_comment(uri_too_long) --> 1585 "URI Too Long". 1586status_comment(unsupported_media_type) --> 1587 "Unsupported Media Type". 1588status_comment(expectation_failed) --> 1589 "Expectation Failed". 1590status_comment(upgrade_required) --> 1591 "Upgrade Required". 1592status_comment(server_error) --> 1593 "Internal Server Error". 1594status_comment(not_implemented) --> 1595 "Not Implemented". 1596status_comment(bad_gateway) --> 1597 "Bad Gateway". 1598status_comment(service_unavailable) --> 1599 "Service Unavailable". 1600status_comment(gateway_timeout) --> 1601 "Gateway Timeout". 1602status_comment(http_version_not_supported) --> 1603 "HTTP Version Not Supported". 1604 1605date(Time) --> 1606 "Date: ", 1607 ( { Time == now } 1608 -> now 1609 ; rfc_date(Time) 1610 ), 1611 "\r\n". 1612 1613modified(file(File)) --> 1614 !, 1615 { time_file(File, Time) 1616 }, 1617 modified(Time). 1618modified(Time) --> 1619 "Last-modified: ", 1620 ( { Time == now } 1621 -> now 1622 ; rfc_date(Time) 1623 ), 1624 "\r\n".
1634content_length(file(File, bytes(From, To)), Len) --> 1635 !, 1636 { size_file(File, Size), 1637 ( To == end 1638 -> Len is Size - From, 1639 RangeEnd is Size - 1 1640 ; Len is To+1 - From, % To is index of last byte 1641 RangeEnd = To 1642 ) 1643 }, 1644 content_range(bytes, From, RangeEnd, Size), 1645 content_length(Len, Len). 1646content_length(Reply, Len) --> 1647 { length_of(Reply, Len) 1648 }, 1649 "Content-Length: ", integer(Len), 1650 "\r\n". 1651 1652 1653length_of(_, Len) :- 1654 nonvar(Len), 1655 !. 1656length_of(string(String, Encoding), Len) :- 1657 length_of(codes(String, Encoding), Len). 1658length_of(codes(String, Encoding), Len) :- 1659 !, 1660 setup_call_cleanup( 1661 open_null_stream(Out), 1662 ( set_stream(Out, encoding(Encoding)), 1663 format(Out, '~s', [String]), 1664 byte_count(Out, Len) 1665 ), 1666 close(Out)). 1667length_of(atom(Atom, Encoding), Len) :- 1668 !, 1669 setup_call_cleanup( 1670 open_null_stream(Out), 1671 ( set_stream(Out, encoding(Encoding)), 1672 format(Out, '~a', [Atom]), 1673 byte_count(Out, Len) 1674 ), 1675 close(Out)). 1676length_of(file(File), Len) :- 1677 !, 1678 size_file(File, Len). 1679length_of(memory_file(Handle), Len) :- 1680 !, 1681 size_memory_file(Handle, Len, octet). 1682length_of(html_tokens(Tokens), Len) :- 1683 !, 1684 html_print_length(Tokens, Len). 1685length_of(html(Tokens), Len) :- % deprecated 1686 !, 1687 html_print_length(Tokens, Len). 1688length_of(bytes(Bytes), Len) :- 1689 !, 1690 ( string(Bytes) 1691 -> string_length(Bytes, Len) 1692 ; length(Bytes, Len) % assuming a list of 0..255 1693 ). 1694length_of(Len, Len).
Content-Range header for partial content (206)
replies.1702content_range(Unit, From, RangeEnd, Size) --> 1703 "Content-Range: ", atom(Unit), " ", 1704 integer(From), "-", integer(RangeEnd), "/", integer(Size), 1705 "\r\n". 1706 1707content_encoding(Encoding) --> 1708 "Content-Encoding: ", atom(Encoding), "\r\n". 1709 1710transfer_encoding(Encoding) --> 1711 "Transfer-Encoding: ", atom(Encoding), "\r\n". 1712 1713content_type(Type) --> 1714 content_type(Type, _). 1715 1716content_type(Type, Charset) --> 1717 ctype(Type), 1718 charset(Charset), 1719 "\r\n". 1720 1721ctype(Main/Sub) --> 1722 !, 1723 "Content-Type: ", 1724 atom(Main), 1725 "/", 1726 atom(Sub). 1727ctype(Type) --> 1728 !, 1729 "Content-Type: ", 1730 atom(Type). 1731 1732charset(Var) --> 1733 { var(Var) }, 1734 !. 1735charset(utf8) --> 1736 !, 1737 "; charset=UTF-8". 1738charset(CharSet) --> 1739 "; charset=", 1740 atom(CharSet).
1748header_field(Name, Value) --> 1749 { var(Name) }, % parsing 1750 !, 1751 field_name(Name), 1752 ":", 1753 whites, 1754 read_field_value(ValueChars), 1755 blanks_to_nl, 1756 !, 1757 { field_to_prolog(Name, ValueChars, Value) 1758 -> true 1759 ; atom_codes(Value, ValueChars), 1760 domain_error(Name, Value) 1761 }. 1762header_field(Name, Value) --> 1763 field_name(Name), 1764 ": ", 1765 field_value(Name, Value), 1766 "\r\n".
1772read_field_value([H|T]) --> 1773 [H], 1774 { \+ code_type(H, space) }, 1775 !, 1776 read_field_value(T). 1777read_field_value([]) --> 1778 "". 1779read_field_value([H|T]) --> 1780 [H], 1781 read_field_value(T).
1788send_reply_header(Out, String) :- 1789 debug(http(send_reply), "< ~s", [String]), 1790 format(Out, '~s', [String]). 1791 1792send_request_header(Out, String) :- 1793 debug(http(send_request), "> ~s", [String]), 1794 format(Out, '~s', [String]).
set_cookie(Name, Value, Options).
Options is a list consisting of Name=Value or a single
atom (e.g., secure)bytes(From, To), where From is an integer
and To is either an integer or the atom end.media(Type, TypeParams, Quality, AcceptExts). The list is
sorted according to preference.disposition(Name, Attributes), where Attributes is
a list of Name=Value pairs.media(Type/SubType, Attributes), where Attributes
is a list of Name=Value pairs.As some fields are already parsed in the Request, this predicate is a no-op when called on an already parsed field.
1834http_parse_header_value(Field, Value, Prolog) :- 1835 known_field(Field, _, Type), 1836 ( already_parsed(Type, Value) 1837 -> Prolog = Value 1838 ; to_codes(Value, Codes), 1839 parse_header_value(Field, Codes, Prolog) 1840 ). 1841 1842already_parsed(integer, V) :- !, integer(V). 1843already_parsed(list(Type), L) :- !, is_list(L), maplist(already_parsed(Type), L). 1844already_parsed(Term, V) :- subsumes_term(Term, V).
1852known_field(content_length, true, integer). 1853known_field(status, true, integer). 1854known_field(cookie, true, list(_=_)). 1855known_field(set_cookie, true, list(set_cookie(_Name,_Value,_Options))). 1856known_field(host, true, _Host:_Port). 1857known_field(range, maybe, bytes(_,_)). 1858known_field(accept, maybe, list(media(_Type, _Parms, _Q, _Exts))). 1859known_field(content_disposition, maybe, disposition(_Name, _Attributes)). 1860known_field(content_type, false, media(_Type/_Sub, _Attributes)). 1861 1862to_codes(In, Codes) :- 1863 ( is_list(In) 1864 -> Codes = In 1865 ; atom_codes(In, Codes) 1866 ).
known_fields(_,true), this must succeed. For maybe, we just
return the atom if the translation fails.1874field_to_prolog(Field, Codes, Prolog) :- 1875 known_field(Field, true, _Type), 1876 !, 1877 ( parse_header_value(Field, Codes, Prolog0) 1878 -> Prolog = Prolog0 1879 ). 1880field_to_prolog(Field, Codes, Prolog) :- 1881 known_field(Field, maybe, _Type), 1882 parse_header_value(Field, Codes, Prolog0), 1883 !, 1884 Prolog = Prolog0. 1885field_to_prolog(_, Codes, Atom) :- 1886 atom_codes(Atom, Codes).
1893parse_header_value(content_length, ValueChars, ContentLength) :- 1894 number_codes(ContentLength, ValueChars). 1895parse_header_value(status, ValueChars, Code) :- 1896 ( phrase(" ", L, _), 1897 append(Pre, L, ValueChars) 1898 -> number_codes(Code, Pre) 1899 ; number_codes(Code, ValueChars) 1900 ). 1901parse_header_value(cookie, ValueChars, Cookies) :- 1902 debug(cookie, 'Cookie: ~s', [ValueChars]), 1903 phrase(cookies(Cookies), ValueChars). 1904parse_header_value(set_cookie, ValueChars, SetCookie) :- 1905 debug(cookie, 'SetCookie: ~s', [ValueChars]), 1906 phrase(set_cookie(SetCookie), ValueChars). 1907parse_header_value(host, ValueChars, Host) :- 1908 ( append(HostChars, [0':|PortChars], ValueChars), 1909 catch(number_codes(Port, PortChars), _, fail) 1910 -> atom_codes(HostName, HostChars), 1911 Host = HostName:Port 1912 ; atom_codes(Host, ValueChars) 1913 ). 1914parse_header_value(range, ValueChars, Range) :- 1915 phrase(range(Range), ValueChars). 1916parse_header_value(accept, ValueChars, Media) :- 1917 parse_accept(ValueChars, Media). 1918parse_header_value(content_disposition, ValueChars, Disposition) :- 1919 phrase(content_disposition(Disposition), ValueChars). 1920parse_header_value(content_type, ValueChars, Type) :- 1921 phrase(parse_content_type(Type), ValueChars).
1925field_value(_, set_cookie(Name, Value, Options)) --> 1926 !, 1927 atom(Name), "=", atom(Value), 1928 value_options(Options, cookie). 1929field_value(_, disposition(Disposition, Options)) --> 1930 !, 1931 atom(Disposition), value_options(Options, disposition). 1932field_value(www_authenticate, Auth) --> 1933 auth_field_value(Auth). 1934field_value(_, Atomic) --> 1935 atom(Atomic).
1941auth_field_value(negotiate(Data)) --> 1942 "Negotiate ", 1943 { base64(Data, DataBase64), 1944 atom_codes(DataBase64, Codes) 1945 }, 1946 string(Codes). 1947auth_field_value(negotiate) --> 1948 "Negotiate". 1949auth_field_value(basic) --> 1950 !, 1951 "Basic". 1952auth_field_value(basic(Realm)) --> 1953 "Basic Realm=\"", atom(Realm), "\"". 1954auth_field_value(digest) --> 1955 !, 1956 "Digest". 1957auth_field_value(digest(Details)) --> 1958 "Digest ", atom(Details).
; charset=UTF-8. There
are three versions: a plain key (secure), token values
and quoted string values. Seems we cannot deduce that from
the actual value.1967value_options([], _) --> []. 1968value_options([H|T], Field) --> 1969 "; ", value_option(H, Field), 1970 value_options(T, Field). 1971 1972value_option(secure=true, cookie) --> 1973 !, 1974 "secure". 1975value_option(Name=Value, Type) --> 1976 { string_option(Name, Type) }, 1977 !, 1978 atom(Name), "=", 1979 qstring(Value). 1980value_option(Name=Value, Type) --> 1981 { token_option(Name, Type) }, 1982 !, 1983 atom(Name), "=", atom(Value). 1984value_option(Name=Value, _Type) --> 1985 atom(Name), "=", 1986 option_value(Value). 1987 1988string_option(filename, disposition). 1989 1990token_option(path, cookie). 1991 1992option_value(Value) --> 1993 { number(Value) }, 1994 !, 1995 number(Value). 1996option_value(Value) --> 1997 { ( atom(Value) 1998 -> true 1999 ; string(Value) 2000 ), 2001 forall(string_code(_, Value, C), 2002 token_char(C)) 2003 }, 2004 !, 2005 atom(Value). 2006option_value(Atomic) --> 2007 qstring(Atomic). 2008 2009qstring(Atomic) --> 2010 { string_codes(Atomic, Codes) }, 2011 "\"", 2012 qstring_codes(Codes), 2013 "\"". 2014 2015qstring_codes([]) --> []. 2016qstring_codes([H|T]) --> qstring_code(H), qstring_codes(T). 2017 2018qstring_code(C) --> {qstring_esc(C)}, !, "\\", [C]. 2019qstring_code(C) --> [C]. 2020 2021qstring_esc(0'"). 2022qstring_esc(C) :- ctl(C). 2023 2024 2025 /******************************* 2026 * ACCEPT HEADERS * 2027 *******************************/ 2028 2029:- dynamic accept_cache/2. 2030:- volatile accept_cache/2. 2031 2032parse_accept(Codes, Media) :- 2033 atom_codes(Atom, Codes), 2034 ( accept_cache(Atom, Media0) 2035 -> Media = Media0 2036 ; phrase(accept(Media0), Codes), 2037 keysort(Media0, Media1), 2038 pairs_values(Media1, Media2), 2039 assertz(accept_cache(Atom, Media2)), 2040 Media = Media2 2041 ).
2047accept([H|T]) --> 2048 blanks, 2049 media_range(H), 2050 blanks, 2051 ( "," 2052 -> accept(T) 2053 ; {T=[]} 2054 ). 2055 2056media_range(s(SortQuality,Spec)-media(Type, TypeParams, Quality, AcceptExts)) --> 2057 media_type(Type), 2058 blanks, 2059 ( ";" 2060 -> blanks, 2061 parameters_and_quality(TypeParams, Quality, AcceptExts) 2062 ; { TypeParams = [], 2063 Quality = 1.0, 2064 AcceptExts = [] 2065 } 2066 ), 2067 { SortQuality is float(-Quality), 2068 rank_specialised(Type, TypeParams, Spec) 2069 }.
2076content_disposition(disposition(Disposition, Options)) -->
2077 token(Disposition), blanks,
2078 value_parameters(Options).media(Type/SubType,
Parameters).
2085parse_content_type(media(Type, Parameters)) -->
2086 media_type(Type), blanks,
2087 value_parameters(Parameters).2098rank_specialised(Type/SubType, TypeParams, v(VT, VS, SortVP)) :- 2099 var_or_given(Type, VT), 2100 var_or_given(SubType, VS), 2101 length(TypeParams, VP), 2102 SortVP is -VP. 2103 2104var_or_given(V, Val) :- 2105 ( var(V) 2106 -> Val = 0 2107 ; Val = -1 2108 ). 2109 2110media_type(Type/SubType) --> 2111 type(Type), "/", type(SubType). 2112 2113type(_) --> 2114 "*", 2115 !. 2116type(Type) --> 2117 token(Type). 2118 2119parameters_and_quality(Params, Quality, AcceptExts) --> 2120 token(Name), 2121 blanks, "=", blanks, 2122 ( { Name == q } 2123 -> float(Quality), blanks, 2124 value_parameters(AcceptExts), 2125 { Params = [] } 2126 ; { Params = [Name=Value|T] }, 2127 parameter_value(Value), 2128 blanks, 2129 ( ";" 2130 -> blanks, 2131 parameters_and_quality(T, Quality, AcceptExts) 2132 ; { T = [], 2133 Quality = 1.0, 2134 AcceptExts = [] 2135 } 2136 ) 2137 ).
2144value_parameters([H|T]) --> 2145 ";", 2146 !, 2147 blanks, token(Name), blanks, 2148 ( "=" 2149 -> blanks, 2150 ( token(Value) 2151 -> [] 2152 ; quoted_string(Value) 2153 ), 2154 { H = (Name=Value) } 2155 ; { H = Name } 2156 ), 2157 blanks, 2158 value_parameters(T). 2159value_parameters([]) --> 2160 []. 2161 2162parameter_value(Value) --> token(Value), !. 2163parameter_value(Value) --> quoted_string(Value).
2170token(Name) --> 2171 token_char(C1), 2172 token_chars(Cs), 2173 { atom_codes(Name, [C1|Cs]) }. 2174 2175token_chars([H|T]) --> 2176 token_char(H), 2177 !, 2178 token_chars(T). 2179token_chars([]) --> []. 2180 2181token_char(C) :- 2182 \+ ctl(C), 2183 \+ separator_code(C). 2184 2185ctl(C) :- between(0,31,C), !. 2186ctl(127). 2187 2188separator_code(0'(). 2189separator_code(0')). 2190separator_code(0'<). 2191separator_code(0'>). 2192separator_code(0'@). 2193separator_code(0',). 2194separator_code(0';). 2195separator_code(0':). 2196separator_code(0'\\). 2197separator_code(0'"). 2198separator_code(0'/). 2199separator_code(0'[). 2200separator_code(0']). 2201separator_code(0'?). 2202separator_code(0'=). 2203separator_code(0'{). 2204separator_code(0'}). 2205separator_code(0'\s). 2206separator_code(0'\t). 2207 2208term_expansion(token_char(x) --> [x], Clauses) :- 2209 findall((token_char(C)-->[C]), 2210 ( between(0, 255, C), 2211 token_char(C) 2212 ), 2213 Clauses). 2214 2215token_char(x) --> [x].
2221quoted_string(Text) --> 2222 "\"", 2223 quoted_text(Codes), 2224 { atom_codes(Text, Codes) }. 2225 2226quoted_text([]) --> 2227 "\"", 2228 !. 2229quoted_text([H|T]) --> 2230 "\\", !, [H], 2231 quoted_text(T). 2232quoted_text([H|T]) --> 2233 [H], 2234 !, 2235 quoted_text(T).
content_length(Len) is special. If instantiated
it emits the header. If not it just unifies ContentLength with
the argument of the content_length(Len) term. This allows for
both sending and retrieving the content-length.2246header_fields([], _) --> []. 2247header_fields([content_length(CLen)|T], CLen) --> 2248 !, 2249 ( { var(CLen) } 2250 -> "" 2251 ; header_field(content_length, CLen) 2252 ), 2253 header_fields(T, CLen). % Continue or return first only? 2254header_fields([status(_)|T], CLen) --> % handled by vstatus//3. 2255 !, 2256 header_fields(T, CLen). 2257header_fields([H|T], CLen) --> 2258 { H =.. [Name, Value] }, 2259 header_field(Name, Value), 2260 header_fields(T, CLen).
token = 1*<any CHAR except CTLs or separators>
separators = "(" | ")" | "<" | ">" | "@"
| "," | ";" | ":" | "\" | <">
| "/" | "[" | "]" | "?" | "="
| "{" | "}" | SP | HT
2277:- public 2278 field_name//1. 2279 2280field_name(Name) --> 2281 { var(Name) }, 2282 !, 2283 rd_field_chars(Chars), 2284 { atom_codes(Name, Chars) }. 2285field_name(mime_version) --> 2286 !, 2287 "MIME-Version". 2288field_name(www_authenticate) --> 2289 !, 2290 "WWW-Authenticate". 2291field_name(Name) --> 2292 { atom_codes(Name, Chars) }, 2293 wr_field_chars(Chars). 2294 2295rd_field_chars_no_fold([C|T]) --> 2296 [C], 2297 { rd_field_char(C, _) }, 2298 !, 2299 rd_field_chars_no_fold(T). 2300rd_field_chars_no_fold([]) --> 2301 []. 2302 2303rd_field_chars([C0|T]) --> 2304 [C], 2305 { rd_field_char(C, C0) }, 2306 !, 2307 rd_field_chars(T). 2308rd_field_chars([]) --> 2309 [].
2315separators("()<>@,;:\\\"/[]?={} \t"). 2316 2317term_expansion(rd_field_char('expand me',_), Clauses) :- 2318 2319 Clauses = [ rd_field_char(0'-, 0'_) 2320 | Cls 2321 ], 2322 separators(SepString), 2323 string_codes(SepString, Seps), 2324 findall(rd_field_char(In, Out), 2325 ( between(32, 127, In), 2326 \+ memberchk(In, Seps), 2327 In \== 0'-, % 0' 2328 code_type(Out, to_lower(In))), 2329 Cls). 2330 2331rd_field_char('expand me', _). % avoid recursion 2332 2333wr_field_chars([C|T]) --> 2334 !, 2335 { code_type(C, to_lower(U)) }, 2336 [U], 2337 wr_field_chars2(T). 2338wr_field_chars([]) --> 2339 []. 2340 2341wr_field_chars2([]) --> []. 2342wr_field_chars2([C|T]) --> % 0' 2343 ( { C == 0'_ } 2344 -> "-", 2345 wr_field_chars(T) 2346 ; [C], 2347 wr_field_chars2(T) 2348 ).
2354now -->
2355 { get_time(Time)
2356 },
2357 rfc_date(Time).
2364rfc_date(Time, String, Tail) :-
2365 stamp_date_time(Time, Date, 'UTC'),
2366 format_time(codes(String, Tail),
2367 '%a, %d %b %Y %T GMT',
2368 Date, posix).2374http_timestamp(Time, Atom) :- 2375 stamp_date_time(Time, Date, 'UTC'), 2376 format_time(atom(Atom), 2377 '%a, %d %b %Y %T GMT', 2378 Date, posix). 2379 2380 2381 /******************************* 2382 * REQUEST DCG * 2383 *******************************/ 2384 2385request(Fd, [method(Method),request_uri(ReqURI)|Header]) --> 2386 method(Method), 2387 blanks, 2388 nonblanks(Query), 2389 { atom_codes(ReqURI, Query), 2390 request_uri_parts(ReqURI, Header, Rest) 2391 }, 2392 request_header(Fd, Rest), 2393 !. 2394request(Fd, [unknown(What)|Header]) --> 2395 string(What), 2396 eos, 2397 !, 2398 { http_read_header(Fd, Header) 2399 -> true 2400 ; Header = [] 2401 }. 2402 2403method(get) --> "GET", !. 2404method(put) --> "PUT", !. 2405method(head) --> "HEAD", !. 2406method(post) --> "POST", !. 2407method(delete) --> "DELETE", !. 2408method(patch) --> "PATCH", !. 2409method(options) --> "OPTIONS", !. 2410method(trace) --> "TRACE", !.
2424request_uri_parts(ReqURI, [path(Path)|Parts], Rest) :- 2425 uri_components(ReqURI, Components), 2426 uri_data(path, Components, PathText), 2427 uri_encoded(path, Path, PathText), 2428 phrase(uri_parts(Components), Parts, Rest). 2429 2430uri_parts(Components) --> 2431 uri_search(Components), 2432 uri_fragment(Components). 2433 2434uri_search(Components) --> 2435 { uri_data(search, Components, Search), 2436 nonvar(Search), 2437 catch(uri_query_components(Search, Query), 2438 error(syntax_error(_),_), 2439 fail) 2440 }, 2441 !, 2442 [ search(Query) ]. 2443uri_search(_) --> []. 2444 2445uri_fragment(Components) --> 2446 { uri_data(fragment, Components, String), 2447 nonvar(String), 2448 !, 2449 uri_encoded(fragment, Fragment, String) 2450 }, 2451 [ fragment(Fragment) ]. 2452uri_fragment(_) --> [].
2459request_header(_, []) --> % Old-style non-version header 2460 blanks, 2461 eos, 2462 !. 2463request_header(Fd, [http_version(Version)|Header]) --> 2464 http_version(Version), 2465 blanks, 2466 eos, 2467 !, 2468 { Version = 1-_ 2469 -> http_read_header(Fd, Header) 2470 ; Header = [] 2471 }. 2472 2473http_version(Version) --> 2474 blanks, 2475 "HTTP/", 2476 http_version_number(Version). 2477 2478http_version_number(Major-Minor) --> 2479 integer(Major), 2480 ".", 2481 integer(Minor). 2482 2483 2484 /******************************* 2485 * COOKIES * 2486 *******************************/
2492cookies([Name=Value|T]) --> 2493 blanks, 2494 cookie(Name, Value), 2495 !, 2496 blanks, 2497 ( ";" 2498 -> cookies(T) 2499 ; { T = [] } 2500 ). 2501cookies(List) --> 2502 string(Skipped), 2503 ";", 2504 !, 2505 { print_message(warning, http(skipped_cookie(Skipped))) }, 2506 cookies(List). 2507cookies([]) --> 2508 blanks. 2509 (Name, Value) --> 2511 cookie_name(Name), 2512 blanks, "=", blanks, 2513 cookie_value(Value). 2514 (Name) --> 2516 { var(Name) }, 2517 !, 2518 rd_field_chars_no_fold(Chars), 2519 { atom_codes(Name, Chars) }. 2520 (Value) --> 2522 quoted_string(Value), 2523 !. 2524cookie_value(Value) --> 2525 chars_to_semicolon_or_blank(Chars), 2526 { atom_codes(Value, Chars) 2527 }. 2528 2529chars_to_semicolon_or_blank([]), ";" --> 2530 ";", 2531 !. 2532chars_to_semicolon_or_blank([]) --> 2533 " ", 2534 blanks, 2535 eos, 2536 !. 2537chars_to_semicolon_or_blank([H|T]) --> 2538 [H], 2539 !, 2540 chars_to_semicolon_or_blank(T). 2541chars_to_semicolon_or_blank([]) --> 2542 []. 2543 (set_cookie(Name, Value, Options)) --> 2545 ws, 2546 cookie(Name, Value), 2547 cookie_options(Options). 2548 ([H|T]) --> 2550 ws, 2551 ";", 2552 ws, 2553 cookie_option(H), 2554 !, 2555 cookie_options(T). 2556cookie_options([]) --> 2557 ws. 2558 2559ws --> " ", !, ws. 2560ws --> [].
Secure and HttpOnly.
2572cookie_option(Name=Value) --> 2573 rd_field_chars(NameChars), ws, 2574 { atom_codes(Name, NameChars) }, 2575 ( "=" 2576 -> ws, 2577 chars_to_semicolon(ValueChars), 2578 { atom_codes(Value, ValueChars) 2579 } 2580 ; { Value = true } 2581 ). 2582 2583chars_to_semicolon([H|T]) --> 2584 [H], 2585 { H \== 32, H \== 0'; }, 2586 !, 2587 chars_to_semicolon(T). 2588chars_to_semicolon([]), ";" --> 2589 ws, ";", 2590 !. 2591chars_to_semicolon([H|T]) --> 2592 [H], 2593 chars_to_semicolon(T). 2594chars_to_semicolon([]) --> 2595 [].
end.2605range(bytes(From, To)) --> 2606 "bytes", whites, "=", whites, integer(From), "-", 2607 ( integer(To) 2608 -> "" 2609 ; { To = end } 2610 ). 2611 2612 2613 /******************************* 2614 * REPLY DCG * 2615 *******************************/
2632reply(Fd, [http_version(HttpVersion), status(Code, Status, Comment)|Header]) --> 2633 http_version(HttpVersion), 2634 blanks, 2635 ( status_number(Status, Code) 2636 -> [] 2637 ; integer(Status) 2638 ), 2639 blanks, 2640 string(CommentCodes), 2641 blanks_to_nl, 2642 !, 2643 blanks, 2644 { atom_codes(Comment, CommentCodes), 2645 http_read_header(Fd, Header) 2646 }. 2647 2648 2649 /******************************* 2650 * READ HEADER * 2651 *******************************/
content_type(text/html)2659http_read_header(Fd, Header) :- 2660 read_header_data(Fd, Text), 2661 http_parse_header(Text, Header). 2662 2663read_header_data(Fd, Header) :- 2664 read_line_to_codes(Fd, Header, Tail), 2665 read_header_data(Header, Fd, Tail), 2666 debug(http(header), 'Header = ~n~s~n', [Header]). 2667 2668read_header_data([0'\r,0'\n], _, _) :- !. 2669read_header_data([0'\n], _, _) :- !. 2670read_header_data([], _, _) :- !. 2671read_header_data(_, Fd, Tail) :- 2672 read_line_to_codes(Fd, Tail, NewTail), 2673 read_header_data(Tail, Fd, NewTail).
2682http_parse_header(Text, Header) :- 2683 phrase(header(Header), Text), 2684 debug(http(header), 'Field: ~p', [Header]). 2685 2686header(List) --> 2687 header_field(Name, Value), 2688 !, 2689 { mkfield(Name, Value, List, Tail) 2690 }, 2691 blanks, 2692 header(Tail). 2693header([]) --> 2694 blanks, 2695 eos, 2696 !. 2697header(_) --> 2698 string(S), blanks_to_nl, 2699 !, 2700 { string_codes(Line, S), 2701 syntax_error(http_parameter(Line)) 2702 }.
SWI-Prolog httpd at <hostname>
The address can be modified by providing a definition for the multifile predicate http:http_address//0.
2716:- multifile 2717 http:http_address//0. 2718 2719address --> 2720 http:http_address, 2721 !. 2722address --> 2723 { gethostname(Host) }, 2724 html(address([ a(href('http://www.swi-prolog.org'), 'SWI-Prolog'), 2725 ' httpd at ', Host 2726 ])). 2727 2728mkfield(host, Host:Port, [host(Host),port(Port)|Tail], Tail) :- !. 2729mkfield(Name, Value, [Att|Tail], Tail) :- 2730 Att =.. [Name, Value].
created(Location)moved(To)moved_temporary(To)see_other(To)bad_request(ErrorTerm)authorise(AuthMethod)forbidden(URL)not_found(URL)method_not_allowed(Method,URL)not_acceptable(Why)server_error(ErrorTerm)unavailable(Why)
The hook is tried twice, first using the status term, e.g.,
not_found(URL) and than with the code, e.g. 404. The second
call is deprecated and only exists for compatibility.
2769 /******************************* 2770 * MESSAGES * 2771 *******************************/ 2772 2773:- multifile 2774 prolog:message//1, 2775 prolog:error_message//1. 2776 2777prologerror_message(http_write_short(Data, Sent)) --> 2778 data(Data), 2779 [ ': remote hangup after ~D bytes'-[Sent] ]. 2780prologerror_message(syntax_error(http_request(Request))) --> 2781 [ 'Illegal HTTP request: ~s'-[Request] ]. 2782prologerror_message(syntax_error(http_parameter(Line))) --> 2783 [ 'Illegal HTTP parameter: ~s'-[Line] ]. 2784 2785prologmessage(http(skipped_cookie(S))) --> 2786 [ 'Skipped illegal cookie: ~s'-[S] ]. 2787 2788data(bytes(MimeType, _Bytes)) --> 2789 !, 2790 [ 'bytes(~p, ...)'-[MimeType] ]. 2791data(Data) --> 2792 [ '~p'-[Data] ]
Handling HTTP headers
The library library(http/http_header) provides primitives for parsing and composing HTTP headers. Its functionality is normally hidden by the other parts of the HTTP server and client libraries. */