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, Encoding, Header) :- 780 memberchk(content_type(Type), Header0), 781 !, 782 http_update_encoding(Type, Header0, Encoding, Header). 783http_update_encoding(Header, octet, Header). 784 785http_update_encoding('text/event-stream', Header, utf8, Header) :- 786 !. 787http_update_encoding(Type0, Header0, utf8, [content_type(Type)|Header]) :- 788 sub_atom(Type0, 0, _, _, 'text/'), 789 !, 790 select(content_type(_), Header0, Header), 791 !, 792 ( sub_atom(Type0, S, _, _, ';') 793 -> sub_atom(Type0, 0, S, _, B) 794 ; B = Type0 795 ), 796 atom_concat(B, '; charset=UTF-8', Type). 797http_update_encoding(Type, Header, Encoding, Header) :- 798 ( sub_atom_icasechk(Type, _, 'utf-8') 799 -> Encoding = utf8 800 ; http:mime_type_encoding(Type, Encoding) 801 -> true 802 ; mime_type_encoding(Type, Encoding) 803 -> true 804 ; Encoding = octet 805 ).
812mime_type_encoding('application/json', utf8). 813mime_type_encoding('application/jsonrequest', utf8). 814mime_type_encoding('application/x-prolog', utf8). 815mime_type_encoding('application/n-quads', utf8). 816mime_type_encoding('application/n-triples', utf8). 817mime_type_encoding('application/sparql-query', utf8). 818mime_type_encoding('application/trig', utf8). 819mime_type_encoding('application/sparql-results+json', utf8). 820mime_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.836http_update_connection(CgiHeader, Request, Connect, 837 [connection(Connect)|Rest]) :- 838 select(connection(CgiConn), CgiHeader, Rest), 839 !, 840 connection(Request, ReqConnection), 841 join_connection(ReqConnection, CgiConn, Connect). 842http_update_connection(CgiHeader, Request, Connect, 843 [connection(Connect)|CgiHeader]) :- 844 connection(Request, Connect). 845 846join_connection(Keep1, Keep2, Connection) :- 847 ( downcase_atom(Keep1, 'keep-alive'), 848 downcase_atom(Keep2, 'keep-alive') 849 -> Connection = 'Keep-Alive' 850 ; Connection = close 851 ).
858connection(Header, Close) :-
859 ( memberchk(connection(Connection), Header)
860 -> Close = Connection
861 ; memberchk(http_version(1-X), Header),
862 X >= 1
863 -> Close = 'Keep-Alive'
864 ; Close = close
865 ).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.
884http_update_transfer(Request, CgiHeader, Transfer, Header) :- 885 setting(http:chunked_transfer, When), 886 http_update_transfer(When, Request, CgiHeader, Transfer, Header). 887 888http_update_transfer(never, _, CgiHeader, none, Header) :- 889 !, 890 delete(CgiHeader, transfer_encoding(_), Header). 891http_update_transfer(_, _, CgiHeader, none, Header) :- 892 memberchk(location(_), CgiHeader), 893 !, 894 delete(CgiHeader, transfer_encoding(_), Header). 895http_update_transfer(_, Request, CgiHeader, Transfer, Header) :- 896 select(transfer_encoding(CgiTransfer), CgiHeader, Rest), 897 !, 898 transfer(Request, ReqConnection), 899 join_transfer(ReqConnection, CgiTransfer, Transfer), 900 ( Transfer == none 901 -> Header = Rest 902 ; Header = [transfer_encoding(Transfer)|Rest] 903 ). 904http_update_transfer(if_possible, Request, CgiHeader, Transfer, Header) :- 905 transfer(Request, Transfer), 906 Transfer \== none, 907 !, 908 Header = [transfer_encoding(Transfer)|CgiHeader]. 909http_update_transfer(_, _, CgiHeader, event_stream, CgiHeader) :- 910 memberchk(content_type('text/event-stream'), CgiHeader), 911 !. 912http_update_transfer(_, _, CgiHeader, none, CgiHeader). 913 914join_transfer(chunked, chunked, chunked) :- !. 915join_transfer(_, _, none).
922transfer(Header, Transfer) :-
923 ( memberchk(transfer_encoding(Transfer0), Header)
924 -> Transfer = Transfer0
925 ; memberchk(http_version(1-X), Header),
926 X >= 1
927 -> Transfer = chunked
928 ; Transfer = none
929 ).938content_length_in_encoding(Enc, Stream, Bytes) :- 939 stream_property(Stream, position(Here)), 940 setup_call_cleanup( 941 open_null_stream(Out), 942 ( set_stream(Out, encoding(Enc)), 943 catch(copy_stream_data(Stream, Out), _, fail), 944 flush_output(Out), 945 byte_count(Out, Bytes) 946 ), 947 ( close(Out, [force(true)]), 948 set_stream_position(Stream, Here) 949 )). 950 951 952 /******************************* 953 * POST SUPPORT * 954 *******************************/
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,
[]),
...,
1062http_post_data(Data, Out, HdrExtra) :- 1063 http:post_data_hook(Data, Out, HdrExtra), 1064 !. 1065http_post_data(html(HTML), Out, HdrExtra) :- 1066 !, 1067 phrase(post_header(html(HTML), HdrExtra), Header), 1068 send_request_header(Out, Header), 1069 print_html(Out, HTML). 1070http_post_data(xml(XML), Out, HdrExtra) :- 1071 !, 1072 http_post_data(xml(text/xml, XML, []), Out, HdrExtra). 1073http_post_data(xml(Type, XML), Out, HdrExtra) :- 1074 !, 1075 http_post_data(xml(Type, XML, []), Out, HdrExtra). 1076http_post_data(xml(Type, XML, Options), Out, HdrExtra) :- 1077 !, 1078 setup_call_cleanup( 1079 new_memory_file(MemFile), 1080 ( setup_call_cleanup( 1081 open_memory_file(MemFile, write, MemOut), 1082 xml_write(MemOut, XML, Options), 1083 close(MemOut)), 1084 http_post_data(memory_file(Type, MemFile), Out, HdrExtra) 1085 ), 1086 free_memory_file(MemFile)). 1087http_post_data(file(File), Out, HdrExtra) :- 1088 !, 1089 ( file_mime_type(File, Type) 1090 -> true 1091 ; Type = text/plain 1092 ), 1093 http_post_data(file(Type, File), Out, HdrExtra). 1094http_post_data(file(Type, File), Out, HdrExtra) :- 1095 !, 1096 phrase(post_header(file(Type, File), HdrExtra), Header), 1097 send_request_header(Out, Header), 1098 setup_call_cleanup( 1099 open(File, read, In, [type(binary)]), 1100 copy_stream_data(In, Out), 1101 close(In)). 1102http_post_data(memory_file(Type, Handle), Out, HdrExtra) :- 1103 !, 1104 phrase(post_header(memory_file(Type, Handle), HdrExtra), Header), 1105 send_request_header(Out, Header), 1106 setup_call_cleanup( 1107 open_memory_file(Handle, read, In, [encoding(octet)]), 1108 copy_stream_data(In, Out), 1109 close(In)). 1110http_post_data(codes(Codes), Out, HdrExtra) :- 1111 !, 1112 http_post_data(codes(text/plain, Codes), Out, HdrExtra). 1113http_post_data(codes(Type, Codes), Out, HdrExtra) :- 1114 !, 1115 phrase(post_header(codes(Type, Codes), HdrExtra), Header), 1116 send_request_header(Out, Header), 1117 setup_call_cleanup( 1118 set_stream(Out, encoding(utf8)), 1119 format(Out, '~s', [Codes]), 1120 set_stream(Out, encoding(octet))). 1121http_post_data(bytes(Type, Bytes), Out, HdrExtra) :- 1122 !, 1123 phrase(post_header(bytes(Type, Bytes), HdrExtra), Header), 1124 send_request_header(Out, Header), 1125 format(Out, '~s', [Bytes]). 1126http_post_data(atom(Atom), Out, HdrExtra) :- 1127 !, 1128 http_post_data(atom(text/plain, Atom), Out, HdrExtra). 1129http_post_data(atom(Type, Atom), Out, HdrExtra) :- 1130 !, 1131 phrase(post_header(atom(Type, Atom), HdrExtra), Header), 1132 send_request_header(Out, Header), 1133 setup_call_cleanup( 1134 set_stream(Out, encoding(utf8)), 1135 write(Out, Atom), 1136 set_stream(Out, encoding(octet))). 1137http_post_data(string(String), Out, HdrExtra) :- 1138 !, 1139 http_post_data(atom(text/plain, String), Out, HdrExtra). 1140http_post_data(string(Type, String), Out, HdrExtra) :- 1141 !, 1142 phrase(post_header(string(Type, String), HdrExtra), Header), 1143 send_request_header(Out, Header), 1144 setup_call_cleanup( 1145 set_stream(Out, encoding(utf8)), 1146 write(Out, String), 1147 set_stream(Out, encoding(octet))). 1148http_post_data(cgi_stream(In, _Len), Out, HdrExtra) :- 1149 !, 1150 debug(obsolete, 'Obsolete 2nd argument in cgi_stream(In,Len)', []), 1151 http_post_data(cgi_stream(In), Out, HdrExtra). 1152http_post_data(cgi_stream(In), Out, HdrExtra) :- 1153 !, 1154 http_read_header(In, Header0), 1155 http_update_encoding(Header0, Encoding, Header), 1156 content_length_in_encoding(Encoding, In, Size), 1157 http_join_headers(HdrExtra, Header, Hdr2), 1158 phrase(post_header(cgi_data(Size), Hdr2), HeaderText), 1159 send_request_header(Out, HeaderText), 1160 setup_call_cleanup( 1161 set_stream(Out, encoding(Encoding)), 1162 copy_stream_data(In, Out), 1163 set_stream(Out, encoding(octet))). 1164http_post_data(form(Fields), Out, HdrExtra) :- 1165 !, 1166 parse_url_search(Codes, Fields), 1167 length(Codes, Size), 1168 http_join_headers(HdrExtra, 1169 [ content_type('application/x-www-form-urlencoded') 1170 ], Header), 1171 phrase(post_header(cgi_data(Size), Header), HeaderChars), 1172 send_request_header(Out, HeaderChars), 1173 format(Out, '~s', [Codes]). 1174http_post_data(form_data(Data), Out, HdrExtra) :- 1175 !, 1176 setup_call_cleanup( 1177 new_memory_file(MemFile), 1178 ( setup_call_cleanup( 1179 open_memory_file(MemFile, write, MimeOut), 1180 mime_pack(Data, MimeOut, Boundary), 1181 close(MimeOut)), 1182 size_memory_file(MemFile, Size, octet), 1183 format(string(ContentType), 1184 'multipart/form-data; boundary=~w', [Boundary]), 1185 http_join_headers(HdrExtra, 1186 [ mime_version('1.0'), 1187 content_type(ContentType) 1188 ], Header), 1189 phrase(post_header(cgi_data(Size), Header), HeaderChars), 1190 send_request_header(Out, HeaderChars), 1191 setup_call_cleanup( 1192 open_memory_file(MemFile, read, In, [encoding(octet)]), 1193 copy_stream_data(In, Out), 1194 close(In)) 1195 ), 1196 free_memory_file(MemFile)). 1197http_post_data(List, Out, HdrExtra) :- % multipart-mixed 1198 is_list(List), 1199 !, 1200 setup_call_cleanup( 1201 new_memory_file(MemFile), 1202 ( setup_call_cleanup( 1203 open_memory_file(MemFile, write, MimeOut), 1204 mime_pack(List, MimeOut, Boundary), 1205 close(MimeOut)), 1206 size_memory_file(MemFile, Size, octet), 1207 format(string(ContentType), 1208 'multipart/mixed; boundary=~w', [Boundary]), 1209 http_join_headers(HdrExtra, 1210 [ mime_version('1.0'), 1211 content_type(ContentType) 1212 ], Header), 1213 phrase(post_header(cgi_data(Size), Header), HeaderChars), 1214 send_request_header(Out, HeaderChars), 1215 setup_call_cleanup( 1216 open_memory_file(MemFile, read, In, [encoding(octet)]), 1217 copy_stream_data(In, Out), 1218 close(In)) 1219 ), 1220 free_memory_file(MemFile)).
1227post_header(html(Tokens), HdrExtra) --> 1228 header_fields(HdrExtra, Len), 1229 content_length(html(Tokens), Len), 1230 content_type(text/html), 1231 "\r\n". 1232post_header(file(Type, File), HdrExtra) --> 1233 header_fields(HdrExtra, Len), 1234 content_length(file(File), Len), 1235 content_type(Type), 1236 "\r\n". 1237post_header(memory_file(Type, File), HdrExtra) --> 1238 header_fields(HdrExtra, Len), 1239 content_length(memory_file(File), Len), 1240 content_type(Type), 1241 "\r\n". 1242post_header(cgi_data(Size), HdrExtra) --> 1243 header_fields(HdrExtra, Len), 1244 content_length(Size, Len), 1245 "\r\n". 1246post_header(codes(Type, Codes), HdrExtra) --> 1247 header_fields(HdrExtra, Len), 1248 content_length(codes(Codes, utf8), Len), 1249 content_type(Type, utf8), 1250 "\r\n". 1251post_header(bytes(Type, Bytes), HdrExtra) --> 1252 header_fields(HdrExtra, Len), 1253 content_length(bytes(Bytes), Len), 1254 content_type(Type), 1255 "\r\n". 1256post_header(atom(Type, Atom), HdrExtra) --> 1257 header_fields(HdrExtra, Len), 1258 content_length(atom(Atom, utf8), Len), 1259 content_type(Type, utf8), 1260 "\r\n". 1261post_header(string(Type, String), HdrExtra) --> 1262 header_fields(HdrExtra, Len), 1263 content_length(string(String, utf8), Len), 1264 content_type(Type, utf8), 1265 "\r\n". 1266 1267 1268 /******************************* 1269 * OUTPUT HEADER DCG * 1270 *******************************/
1277http_reply_header(Out, What, HdrExtra) :-
1278 phrase(reply_header(What, HdrExtra, _Code), String),
1279 !,
1280 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)1304reply_header(Data, Dict) --> 1305 { _{header:HdrExtra, code:Code} :< Dict }, 1306 reply_header(Data, HdrExtra, Code). 1307 1308reply_header(string(String), HdrExtra, Code) --> 1309 reply_header(string(text/plain, String), HdrExtra, Code). 1310reply_header(string(Type, String), HdrExtra, Code) --> 1311 vstatus(ok, Code, HdrExtra), 1312 date(now), 1313 header_fields(HdrExtra, CLen), 1314 content_length(codes(String, utf8), CLen), 1315 content_type(Type, utf8), 1316 "\r\n". 1317reply_header(bytes(Type, Bytes), HdrExtra, Code) --> 1318 vstatus(ok, Code, HdrExtra), 1319 date(now), 1320 header_fields(HdrExtra, CLen), 1321 content_length(bytes(Bytes), CLen), 1322 content_type(Type), 1323 "\r\n". 1324reply_header(html(Tokens), HdrExtra, Code) --> 1325 vstatus(ok, Code, HdrExtra), 1326 date(now), 1327 header_fields(HdrExtra, CLen), 1328 content_length(html(Tokens), CLen), 1329 content_type(text/html), 1330 "\r\n". 1331reply_header(file(Type, File), HdrExtra, Code) --> 1332 vstatus(ok, Code, HdrExtra), 1333 date(now), 1334 modified(file(File)), 1335 header_fields(HdrExtra, CLen), 1336 content_length(file(File), CLen), 1337 content_type(Type), 1338 "\r\n". 1339reply_header(gzip_file(Type, File), HdrExtra, Code) --> 1340 vstatus(ok, Code, HdrExtra), 1341 date(now), 1342 modified(file(File)), 1343 header_fields(HdrExtra, CLen), 1344 content_length(file(File), CLen), 1345 content_type(Type), 1346 content_encoding(gzip), 1347 "\r\n". 1348reply_header(file(Type, File, Range), HdrExtra, Code) --> 1349 vstatus(partial_content, Code, HdrExtra), 1350 date(now), 1351 modified(file(File)), 1352 header_fields(HdrExtra, CLen), 1353 content_length(file(File, Range), CLen), 1354 content_type(Type), 1355 "\r\n". 1356reply_header(tmp_file(Type, File), HdrExtra, Code) --> 1357 vstatus(ok, Code, HdrExtra), 1358 date(now), 1359 header_fields(HdrExtra, CLen), 1360 content_length(file(File), CLen), 1361 content_type(Type), 1362 "\r\n". 1363reply_header(cgi_data(Size), HdrExtra, Code) --> 1364 vstatus(ok, Code, HdrExtra), 1365 date(now), 1366 header_fields(HdrExtra, CLen), 1367 content_length(Size, CLen), 1368 "\r\n". 1369reply_header(event_stream, HdrExtra, Code) --> 1370 vstatus(ok, Code, HdrExtra), 1371 date(now), 1372 header_fields(HdrExtra, _), 1373 "\r\n". 1374reply_header(chunked_data, HdrExtra, Code) --> 1375 vstatus(ok, Code, HdrExtra), 1376 date(now), 1377 header_fields(HdrExtra, _), 1378 ( {memberchk(transfer_encoding(_), HdrExtra)} 1379 -> "" 1380 ; transfer_encoding(chunked) 1381 ), 1382 "\r\n". 1383% non-200 replies without a body (e.g., 1xx, 204, 304) 1384reply_header(status(Status), HdrExtra, Code) --> 1385 vstatus(Status, Code), 1386 header_fields(HdrExtra, Clen), 1387 { Clen = 0 }, 1388 "\r\n". 1389% non-200 replies with a body 1390reply_header(Data, HdrExtra, Code) --> 1391 { status_reply_headers(Data, 1392 body(Type, Encoding, Content), 1393 ReplyHeaders), 1394 http_join_headers(ReplyHeaders, HdrExtra, Headers), 1395 functor(Data, CodeName, _) 1396 }, 1397 vstatus(CodeName, Code, Headers), 1398 date(now), 1399 header_fields(Headers, CLen), 1400 content_length(codes(Content, Encoding), CLen), 1401 content_type(Type, Encoding), 1402 "\r\n". 1403 1404status_reply_headers(created(Location, Body), Body, 1405 [ location(Location) ]). 1406status_reply_headers(moved(To, Body), Body, 1407 [ location(To) ]). 1408status_reply_headers(moved_temporary(To, Body), Body, 1409 [ location(To) ]). 1410status_reply_headers(gone(_URL, Body), Body, []). 1411status_reply_headers(see_other(To, Body), Body, 1412 [ location(To) ]). 1413status_reply_headers(authorise(Method, Body), Body, 1414 [ www_authenticate(Method) ]). 1415status_reply_headers(not_found(_URL, Body), Body, []). 1416status_reply_headers(forbidden(_URL, Body), Body, []). 1417status_reply_headers(method_not_allowed(_Method, _URL, Body), Body, []). 1418status_reply_headers(server_error(_Error, Body), Body, []). 1419status_reply_headers(service_unavailable(_Why, Body), Body, []). 1420status_reply_headers(not_acceptable(_Why, Body), Body, []). 1421status_reply_headers(bad_request(_Error, Body), Body, []).
1429vstatus(_Status, Code, HdrExtra) --> 1430 {memberchk(status(Code), HdrExtra)}, 1431 !, 1432 vstatus(_NewStatus, Code). 1433vstatus(Status, Code, _) --> 1434 vstatus(Status, Code). 1435 1436vstatus(Status, Code) --> 1437 "HTTP/1.1 ", 1438 status_number(Status, Code), 1439 " ", 1440 status_comment(Status), 1441 "\r\n".
1450status_number(Status, Code) --> 1451 { var(Status) }, 1452 !, 1453 integer(Code), 1454 { status_number(Status, Code) }, 1455 !. 1456status_number(Status, Code) --> 1457 { status_number(Status, Code) }, 1458 integer(Code).
1472% Unrecognized status codes that are within a defined code class. 1473% RFC 7231 states: 1474% "[...] a client MUST understand the class of any status code, 1475% as indicated by the first digit, and treat an unrecognized status code 1476% as being equivalent to the `x00` status code of that class [...] 1477% " 1478% @see http://tools.ietf.org/html/rfc7231#section-6 1479 1480status_number(Status, Code) :- 1481 nonvar(Status), 1482 !, 1483 status_number_fact(Status, Code). 1484status_number(Status, Code) :- 1485 nonvar(Code), 1486 !, 1487 ( between(100, 599, Code) 1488 -> ( status_number_fact(Status, Code) 1489 -> true 1490 ; ClassCode is Code // 100 * 100, 1491 status_number_fact(Status, ClassCode) 1492 ) 1493 ; domain_error(http_code, Code) 1494 ). 1495 1496status_number_fact(continue, 100). 1497status_number_fact(switching_protocols, 101). 1498status_number_fact(ok, 200). 1499status_number_fact(created, 201). 1500status_number_fact(accepted, 202). 1501status_number_fact(non_authoritative_info, 203). 1502status_number_fact(no_content, 204). 1503status_number_fact(reset_content, 205). 1504status_number_fact(partial_content, 206). 1505status_number_fact(multiple_choices, 300). 1506status_number_fact(moved, 301). 1507status_number_fact(moved_temporary, 302). 1508status_number_fact(see_other, 303). 1509status_number_fact(not_modified, 304). 1510status_number_fact(use_proxy, 305). 1511status_number_fact(unused, 306). 1512status_number_fact(temporary_redirect, 307). 1513status_number_fact(bad_request, 400). 1514status_number_fact(authorise, 401). 1515status_number_fact(payment_required, 402). 1516status_number_fact(forbidden, 403). 1517status_number_fact(not_found, 404). 1518status_number_fact(method_not_allowed, 405). 1519status_number_fact(not_acceptable, 406). 1520status_number_fact(request_timeout, 408). 1521status_number_fact(conflict, 409). 1522status_number_fact(gone, 410). 1523status_number_fact(length_required, 411). 1524status_number_fact(payload_too_large, 413). 1525status_number_fact(uri_too_long, 414). 1526status_number_fact(unsupported_media_type, 415). 1527status_number_fact(expectation_failed, 417). 1528status_number_fact(upgrade_required, 426). 1529status_number_fact(server_error, 500). 1530status_number_fact(not_implemented, 501). 1531status_number_fact(bad_gateway, 502). 1532status_number_fact(service_unavailable, 503). 1533status_number_fact(gateway_timeout, 504). 1534status_number_fact(http_version_not_supported, 505).
1541status_comment(continue) --> 1542 "Continue". 1543status_comment(switching_protocols) --> 1544 "Switching Protocols". 1545status_comment(ok) --> 1546 "OK". 1547status_comment(created) --> 1548 "Created". 1549status_comment(accepted) --> 1550 "Accepted". 1551status_comment(non_authoritative_info) --> 1552 "Non-Authoritative Information". 1553status_comment(no_content) --> 1554 "No Content". 1555status_comment(reset_content) --> 1556 "Reset Content". 1557status_comment(created) --> 1558 "Created". 1559status_comment(partial_content) --> 1560 "Partial content". 1561status_comment(multiple_choices) --> 1562 "Multiple Choices". 1563status_comment(moved) --> 1564 "Moved Permanently". 1565status_comment(moved_temporary) --> 1566 "Moved Temporary". 1567status_comment(see_other) --> 1568 "See Other". 1569status_comment(not_modified) --> 1570 "Not Modified". 1571status_comment(use_proxy) --> 1572 "Use Proxy". 1573status_comment(unused) --> 1574 "Unused". 1575status_comment(temporary_redirect) --> 1576 "Temporary Redirect". 1577status_comment(bad_request) --> 1578 "Bad Request". 1579status_comment(authorise) --> 1580 "Authorization Required". 1581status_comment(payment_required) --> 1582 "Payment Required". 1583status_comment(forbidden) --> 1584 "Forbidden". 1585status_comment(not_found) --> 1586 "Not Found". 1587status_comment(method_not_allowed) --> 1588 "Method Not Allowed". 1589status_comment(not_acceptable) --> 1590 "Not Acceptable". 1591status_comment(request_timeout) --> 1592 "Request Timeout". 1593status_comment(conflict) --> 1594 "Conflict". 1595status_comment(gone) --> 1596 "Gone". 1597status_comment(length_required) --> 1598 "Length Required". 1599status_comment(payload_too_large) --> 1600 "Payload Too Large". 1601status_comment(uri_too_long) --> 1602 "URI Too Long". 1603status_comment(unsupported_media_type) --> 1604 "Unsupported Media Type". 1605status_comment(expectation_failed) --> 1606 "Expectation Failed". 1607status_comment(upgrade_required) --> 1608 "Upgrade Required". 1609status_comment(server_error) --> 1610 "Internal Server Error". 1611status_comment(not_implemented) --> 1612 "Not Implemented". 1613status_comment(bad_gateway) --> 1614 "Bad Gateway". 1615status_comment(service_unavailable) --> 1616 "Service Unavailable". 1617status_comment(gateway_timeout) --> 1618 "Gateway Timeout". 1619status_comment(http_version_not_supported) --> 1620 "HTTP Version Not Supported". 1621 1622date(Time) --> 1623 "Date: ", 1624 ( { Time == now } 1625 -> now 1626 ; rfc_date(Time) 1627 ), 1628 "\r\n". 1629 1630modified(file(File)) --> 1631 !, 1632 { time_file(File, Time) 1633 }, 1634 modified(Time). 1635modified(Time) --> 1636 "Last-modified: ", 1637 ( { Time == now } 1638 -> now 1639 ; rfc_date(Time) 1640 ), 1641 "\r\n".
1651content_length(file(File, bytes(From, To)), Len) --> 1652 !, 1653 { size_file(File, Size), 1654 ( To == end 1655 -> Len is Size - From, 1656 RangeEnd is Size - 1 1657 ; Len is To+1 - From, % To is index of last byte 1658 RangeEnd = To 1659 ) 1660 }, 1661 content_range(bytes, From, RangeEnd, Size), 1662 content_length(Len, Len). 1663content_length(Reply, Len) --> 1664 { length_of(Reply, Len) 1665 }, 1666 "Content-Length: ", integer(Len), 1667 "\r\n". 1668 1669 1670length_of(_, Len) :- 1671 nonvar(Len), 1672 !. 1673length_of(string(String, Encoding), Len) :- 1674 length_of(codes(String, Encoding), Len). 1675length_of(codes(String, Encoding), Len) :- 1676 !, 1677 setup_call_cleanup( 1678 open_null_stream(Out), 1679 ( set_stream(Out, encoding(Encoding)), 1680 format(Out, '~s', [String]), 1681 byte_count(Out, Len) 1682 ), 1683 close(Out)). 1684length_of(atom(Atom, Encoding), Len) :- 1685 !, 1686 setup_call_cleanup( 1687 open_null_stream(Out), 1688 ( set_stream(Out, encoding(Encoding)), 1689 format(Out, '~a', [Atom]), 1690 byte_count(Out, Len) 1691 ), 1692 close(Out)). 1693length_of(file(File), Len) :- 1694 !, 1695 size_file(File, Len). 1696length_of(memory_file(Handle), Len) :- 1697 !, 1698 size_memory_file(Handle, Len, octet). 1699length_of(html_tokens(Tokens), Len) :- 1700 !, 1701 html_print_length(Tokens, Len). 1702length_of(html(Tokens), Len) :- % deprecated 1703 !, 1704 html_print_length(Tokens, Len). 1705length_of(bytes(Bytes), Len) :- 1706 !, 1707 ( string(Bytes) 1708 -> string_length(Bytes, Len) 1709 ; length(Bytes, Len) % assuming a list of 0..255 1710 ). 1711length_of(Len, Len).
Content-Range header for partial content (206)
replies.1719content_range(Unit, From, RangeEnd, Size) --> 1720 "Content-Range: ", atom(Unit), " ", 1721 integer(From), "-", integer(RangeEnd), "/", integer(Size), 1722 "\r\n". 1723 1724content_encoding(Encoding) --> 1725 "Content-Encoding: ", atom(Encoding), "\r\n". 1726 1727transfer_encoding(Encoding) --> 1728 "Transfer-Encoding: ", atom(Encoding), "\r\n". 1729 1730content_type(Type) --> 1731 content_type(Type, _). 1732 1733content_type(Type, Charset) --> 1734 ctype(Type), 1735 charset(Charset), 1736 "\r\n". 1737 1738ctype(Main/Sub) --> 1739 !, 1740 "Content-Type: ", 1741 atom(Main), 1742 "/", 1743 atom(Sub). 1744ctype(Type) --> 1745 !, 1746 "Content-Type: ", 1747 atom(Type). 1748 1749charset(Var) --> 1750 { var(Var) }, 1751 !. 1752charset(utf8) --> 1753 !, 1754 "; charset=UTF-8". 1755charset(CharSet) --> 1756 "; charset=", 1757 atom(CharSet).
1765header_field(Name, Value) --> 1766 { var(Name) }, % parsing 1767 !, 1768 field_name(Name), 1769 ":", 1770 whites, 1771 read_field_value(ValueChars), 1772 blanks_to_nl, 1773 !, 1774 { field_to_prolog(Name, ValueChars, Value) 1775 -> true 1776 ; atom_codes(Value, ValueChars), 1777 domain_error(Name, Value) 1778 }. 1779header_field(Name, Value) --> 1780 field_name(Name), 1781 ": ", 1782 field_value(Name, Value), 1783 "\r\n".
1789read_field_value([H|T]) --> 1790 [H], 1791 { \+ code_type(H, space) }, 1792 !, 1793 read_field_value(T). 1794read_field_value([]) --> 1795 "". 1796read_field_value([H|T]) --> 1797 [H], 1798 read_field_value(T).
1805send_reply_header(Out, String) :- 1806 debug(http(send_reply), "< ~s", [String]), 1807 format(Out, '~s', [String]). 1808 1809send_request_header(Out, String) :- 1810 debug(http(send_request), "> ~s", [String]), 1811 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.
1851http_parse_header_value(Field, Value, Prolog) :- 1852 known_field(Field, _, Type), 1853 ( already_parsed(Type, Value) 1854 -> Prolog = Value 1855 ; to_codes(Value, Codes), 1856 parse_header_value(Field, Codes, Prolog) 1857 ). 1858 1859already_parsed(integer, V) :- !, integer(V). 1860already_parsed(list(Type), L) :- !, is_list(L), maplist(already_parsed(Type), L). 1861already_parsed(Term, V) :- subsumes_term(Term, V).
1869known_field(content_length, true, integer). 1870known_field(status, true, integer). 1871known_field(cookie, true, list(_=_)). 1872known_field(set_cookie, true, list(set_cookie(_Name,_Value,_Options))). 1873known_field(host, true, _Host:_Port). 1874known_field(range, maybe, bytes(_,_)). 1875known_field(accept, maybe, list(media(_Type, _Parms, _Q, _Exts))). 1876known_field(content_disposition, maybe, disposition(_Name, _Attributes)). 1877known_field(content_type, false, media(_Type/_Sub, _Attributes)). 1878 1879to_codes(In, Codes) :- 1880 ( is_list(In) 1881 -> Codes = In 1882 ; atom_codes(In, Codes) 1883 ).
known_fields(_,true), this must succeed. For maybe, we just
return the atom if the translation fails.1891field_to_prolog(Field, Codes, Prolog) :- 1892 known_field(Field, true, _Type), 1893 !, 1894 ( parse_header_value(Field, Codes, Prolog0) 1895 -> Prolog = Prolog0 1896 ). 1897field_to_prolog(Field, Codes, Prolog) :- 1898 known_field(Field, maybe, _Type), 1899 parse_header_value(Field, Codes, Prolog0), 1900 !, 1901 Prolog = Prolog0. 1902field_to_prolog(_, Codes, Atom) :- 1903 atom_codes(Atom, Codes).
1910parse_header_value(content_length, ValueChars, ContentLength) :- 1911 number_codes(ContentLength, ValueChars). 1912parse_header_value(status, ValueChars, Code) :- 1913 ( phrase(" ", L, _), 1914 append(Pre, L, ValueChars) 1915 -> number_codes(Code, Pre) 1916 ; number_codes(Code, ValueChars) 1917 ). 1918parse_header_value(cookie, ValueChars, Cookies) :- 1919 debug(cookie, 'Cookie: ~s', [ValueChars]), 1920 phrase(cookies(Cookies), ValueChars). 1921parse_header_value(set_cookie, ValueChars, SetCookie) :- 1922 debug(cookie, 'SetCookie: ~s', [ValueChars]), 1923 phrase(set_cookie(SetCookie), ValueChars). 1924parse_header_value(host, ValueChars, Host) :- 1925 ( append(HostChars, [0':|PortChars], ValueChars), 1926 catch(number_codes(Port, PortChars), _, fail) 1927 -> atom_codes(HostName, HostChars), 1928 Host = HostName:Port 1929 ; atom_codes(Host, ValueChars) 1930 ). 1931parse_header_value(range, ValueChars, Range) :- 1932 phrase(range(Range), ValueChars). 1933parse_header_value(accept, ValueChars, Media) :- 1934 parse_accept(ValueChars, Media). 1935parse_header_value(content_disposition, ValueChars, Disposition) :- 1936 phrase(content_disposition(Disposition), ValueChars). 1937parse_header_value(content_type, ValueChars, Type) :- 1938 phrase(parse_content_type(Type), ValueChars).
1942field_value(_, set_cookie(Name, Value, Options)) --> 1943 !, 1944 atom(Name), "=", atom(Value), 1945 value_options(Options, cookie). 1946field_value(_, disposition(Disposition, Options)) --> 1947 !, 1948 atom(Disposition), value_options(Options, disposition). 1949field_value(www_authenticate, Auth) --> 1950 auth_field_value(Auth). 1951field_value(_, Atomic) --> 1952 atom(Atomic).
1958auth_field_value(negotiate(Data)) --> 1959 "Negotiate ", 1960 { base64(Data, DataBase64), 1961 atom_codes(DataBase64, Codes) 1962 }, 1963 string(Codes). 1964auth_field_value(negotiate) --> 1965 "Negotiate". 1966auth_field_value(basic) --> 1967 !, 1968 "Basic". 1969auth_field_value(basic(Realm)) --> 1970 "Basic Realm=\"", atom(Realm), "\"". 1971auth_field_value(digest) --> 1972 !, 1973 "Digest". 1974auth_field_value(digest(Details)) --> 1975 "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.1984value_options([], _) --> []. 1985value_options([H|T], Field) --> 1986 "; ", value_option(H, Field), 1987 value_options(T, Field). 1988 1989value_option(secure=true, cookie) --> 1990 !, 1991 "secure". 1992value_option(Name=Value, Type) --> 1993 { string_option(Name, Type) }, 1994 !, 1995 atom(Name), "=", 1996 qstring(Value). 1997value_option(Name=Value, Type) --> 1998 { token_option(Name, Type) }, 1999 !, 2000 atom(Name), "=", atom(Value). 2001value_option(Name=Value, _Type) --> 2002 atom(Name), "=", 2003 option_value(Value). 2004 2005string_option(filename, disposition). 2006 2007token_option(path, cookie). 2008 2009option_value(Value) --> 2010 { number(Value) }, 2011 !, 2012 number(Value). 2013option_value(Value) --> 2014 { ( atom(Value) 2015 -> true 2016 ; string(Value) 2017 ), 2018 forall(string_code(_, Value, C), 2019 token_char(C)) 2020 }, 2021 !, 2022 atom(Value). 2023option_value(Atomic) --> 2024 qstring(Atomic). 2025 2026qstring(Atomic) --> 2027 { string_codes(Atomic, Codes) }, 2028 "\"", 2029 qstring_codes(Codes), 2030 "\"". 2031 2032qstring_codes([]) --> []. 2033qstring_codes([H|T]) --> qstring_code(H), qstring_codes(T). 2034 2035qstring_code(C) --> {qstring_esc(C)}, !, "\\", [C]. 2036qstring_code(C) --> [C]. 2037 2038qstring_esc(0'"). 2039qstring_esc(C) :- ctl(C). 2040 2041 2042 /******************************* 2043 * ACCEPT HEADERS * 2044 *******************************/ 2045 2046:- dynamic accept_cache/2. 2047:- volatile accept_cache/2. 2048 2049parse_accept(Codes, Media) :- 2050 atom_codes(Atom, Codes), 2051 ( accept_cache(Atom, Media0) 2052 -> Media = Media0 2053 ; phrase(accept(Media0), Codes), 2054 keysort(Media0, Media1), 2055 pairs_values(Media1, Media2), 2056 assertz(accept_cache(Atom, Media2)), 2057 Media = Media2 2058 ).
2064accept([H|T]) --> 2065 blanks, 2066 media_range(H), 2067 blanks, 2068 ( "," 2069 -> accept(T) 2070 ; {T=[]} 2071 ). 2072 2073media_range(s(SortQuality,Spec)-media(Type, TypeParams, Quality, AcceptExts)) --> 2074 media_type(Type), 2075 blanks, 2076 ( ";" 2077 -> blanks, 2078 parameters_and_quality(TypeParams, Quality, AcceptExts) 2079 ; { TypeParams = [], 2080 Quality = 1.0, 2081 AcceptExts = [] 2082 } 2083 ), 2084 { SortQuality is float(-Quality), 2085 rank_specialised(Type, TypeParams, Spec) 2086 }.
2093content_disposition(disposition(Disposition, Options)) -->
2094 token(Disposition), blanks,
2095 value_parameters(Options).media(Type/SubType,
Parameters).
2102parse_content_type(media(Type, Parameters)) -->
2103 media_type(Type), blanks,
2104 value_parameters(Parameters).2115rank_specialised(Type/SubType, TypeParams, v(VT, VS, SortVP)) :- 2116 var_or_given(Type, VT), 2117 var_or_given(SubType, VS), 2118 length(TypeParams, VP), 2119 SortVP is -VP. 2120 2121var_or_given(V, Val) :- 2122 ( var(V) 2123 -> Val = 0 2124 ; Val = -1 2125 ). 2126 2127media_type(Type/SubType) --> 2128 type(Type), "/", type(SubType). 2129 2130type(_) --> 2131 "*", 2132 !. 2133type(Type) --> 2134 token(Type). 2135 2136parameters_and_quality(Params, Quality, AcceptExts) --> 2137 token(Name), 2138 blanks, "=", blanks, 2139 ( { Name == q } 2140 -> float(Quality), blanks, 2141 value_parameters(AcceptExts), 2142 { Params = [] } 2143 ; { Params = [Name=Value|T] }, 2144 parameter_value(Value), 2145 blanks, 2146 ( ";" 2147 -> blanks, 2148 parameters_and_quality(T, Quality, AcceptExts) 2149 ; { T = [], 2150 Quality = 1.0, 2151 AcceptExts = [] 2152 } 2153 ) 2154 ).
2161value_parameters([H|T]) --> 2162 ";", 2163 !, 2164 blanks, token(Name), blanks, 2165 ( "=" 2166 -> blanks, 2167 ( token(Value) 2168 -> [] 2169 ; quoted_string(Value) 2170 ), 2171 { H = (Name=Value) } 2172 ; { H = Name } 2173 ), 2174 blanks, 2175 value_parameters(T). 2176value_parameters([]) --> 2177 []. 2178 2179parameter_value(Value) --> token(Value), !. 2180parameter_value(Value) --> quoted_string(Value).
2187token(Name) --> 2188 token_char(C1), 2189 token_chars(Cs), 2190 { atom_codes(Name, [C1|Cs]) }. 2191 2192token_chars([H|T]) --> 2193 token_char(H), 2194 !, 2195 token_chars(T). 2196token_chars([]) --> []. 2197 2198token_char(C) :- 2199 \+ ctl(C), 2200 \+ separator_code(C). 2201 2202ctl(C) :- between(0,31,C), !. 2203ctl(127). 2204 2205separator_code(0'(). 2206separator_code(0')). 2207separator_code(0'<). 2208separator_code(0'>). 2209separator_code(0'@). 2210separator_code(0',). 2211separator_code(0';). 2212separator_code(0':). 2213separator_code(0'\\). 2214separator_code(0'"). 2215separator_code(0'/). 2216separator_code(0'[). 2217separator_code(0']). 2218separator_code(0'?). 2219separator_code(0'=). 2220separator_code(0'{). 2221separator_code(0'}). 2222separator_code(0'\s). 2223separator_code(0'\t). 2224 2225term_expansion(token_char(x) --> [x], Clauses) :- 2226 findall((token_char(C)-->[C]), 2227 ( between(0, 255, C), 2228 token_char(C) 2229 ), 2230 Clauses). 2231 2232token_char(x) --> [x].
2238quoted_string(Text) --> 2239 "\"", 2240 quoted_text(Codes), 2241 { atom_codes(Text, Codes) }. 2242 2243quoted_text([]) --> 2244 "\"", 2245 !. 2246quoted_text([H|T]) --> 2247 "\\", !, [H], 2248 quoted_text(T). 2249quoted_text([H|T]) --> 2250 [H], 2251 !, 2252 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.2263header_fields([], _) --> []. 2264header_fields([content_length(CLen)|T], CLen) --> 2265 !, 2266 ( { var(CLen) } 2267 -> "" 2268 ; header_field(content_length, CLen) 2269 ), 2270 header_fields(T, CLen). % Continue or return first only? 2271header_fields([status(_)|T], CLen) --> % handled by vstatus//3. 2272 !, 2273 header_fields(T, CLen). 2274header_fields([H|T], CLen) --> 2275 { H =.. [Name, Value] }, 2276 header_field(Name, Value), 2277 header_fields(T, CLen).
token = 1*<any CHAR except CTLs or separators>
separators = "(" | ")" | "<" | ">" | "@"
| "," | ";" | ":" | "\" | <">
| "/" | "[" | "]" | "?" | "="
| "{" | "}" | SP | HT
2294:- public 2295 field_name//1. 2296 2297field_name(Name) --> 2298 { var(Name) }, 2299 !, 2300 rd_field_chars(Chars), 2301 { atom_codes(Name, Chars) }. 2302field_name(mime_version) --> 2303 !, 2304 "MIME-Version". 2305field_name(www_authenticate) --> 2306 !, 2307 "WWW-Authenticate". 2308field_name(Name) --> 2309 { atom_codes(Name, Chars) }, 2310 wr_field_chars(Chars). 2311 2312rd_field_chars_no_fold([C|T]) --> 2313 [C], 2314 { rd_field_char(C, _) }, 2315 !, 2316 rd_field_chars_no_fold(T). 2317rd_field_chars_no_fold([]) --> 2318 []. 2319 2320rd_field_chars([C0|T]) --> 2321 [C], 2322 { rd_field_char(C, C0) }, 2323 !, 2324 rd_field_chars(T). 2325rd_field_chars([]) --> 2326 [].
2332separators("()<>@,;:\\\"/[]?={} \t"). 2333 2334term_expansion(rd_field_char('expand me',_), Clauses) :- 2335 2336 Clauses = [ rd_field_char(0'-, 0'_) 2337 | Cls 2338 ], 2339 separators(SepString), 2340 string_codes(SepString, Seps), 2341 findall(rd_field_char(In, Out), 2342 ( between(32, 127, In), 2343 \+ memberchk(In, Seps), 2344 In \== 0'-, % 0' 2345 code_type(Out, to_lower(In))), 2346 Cls). 2347 2348rd_field_char('expand me', _). % avoid recursion 2349 2350wr_field_chars([C|T]) --> 2351 !, 2352 { code_type(C, to_lower(U)) }, 2353 [U], 2354 wr_field_chars2(T). 2355wr_field_chars([]) --> 2356 []. 2357 2358wr_field_chars2([]) --> []. 2359wr_field_chars2([C|T]) --> % 0' 2360 ( { C == 0'_ } 2361 -> "-", 2362 wr_field_chars(T) 2363 ; [C], 2364 wr_field_chars2(T) 2365 ).
2371now -->
2372 { get_time(Time)
2373 },
2374 rfc_date(Time).
2381rfc_date(Time, String, Tail) :-
2382 stamp_date_time(Time, Date, 'UTC'),
2383 format_time(codes(String, Tail),
2384 '%a, %d %b %Y %T GMT',
2385 Date, posix).2391http_timestamp(Time, Atom) :- 2392 stamp_date_time(Time, Date, 'UTC'), 2393 format_time(atom(Atom), 2394 '%a, %d %b %Y %T GMT', 2395 Date, posix). 2396 2397 2398 /******************************* 2399 * REQUEST DCG * 2400 *******************************/ 2401 2402request(Fd, [method(Method),request_uri(ReqURI)|Header]) --> 2403 method(Method), 2404 blanks, 2405 nonblanks(Query), 2406 { atom_codes(ReqURI, Query), 2407 request_uri_parts(ReqURI, Header, Rest) 2408 }, 2409 request_header(Fd, Rest), 2410 !. 2411request(Fd, [unknown(What)|Header]) --> 2412 string(What), 2413 eos, 2414 !, 2415 { http_read_header(Fd, Header) 2416 -> true 2417 ; Header = [] 2418 }. 2419 2420method(get) --> "GET", !. 2421method(put) --> "PUT", !. 2422method(head) --> "HEAD", !. 2423method(post) --> "POST", !. 2424method(delete) --> "DELETE", !. 2425method(patch) --> "PATCH", !. 2426method(options) --> "OPTIONS", !. 2427method(trace) --> "TRACE", !.
2441request_uri_parts(ReqURI, [path(Path)|Parts], Rest) :- 2442 uri_components(ReqURI, Components), 2443 uri_data(path, Components, PathText), 2444 uri_encoded(path, Path, PathText), 2445 phrase(uri_parts(Components), Parts, Rest). 2446 2447uri_parts(Components) --> 2448 uri_search(Components), 2449 uri_fragment(Components). 2450 2451uri_search(Components) --> 2452 { uri_data(search, Components, Search), 2453 nonvar(Search), 2454 catch(uri_query_components(Search, Query), 2455 error(syntax_error(_),_), 2456 fail) 2457 }, 2458 !, 2459 [ search(Query) ]. 2460uri_search(_) --> []. 2461 2462uri_fragment(Components) --> 2463 { uri_data(fragment, Components, String), 2464 nonvar(String), 2465 !, 2466 uri_encoded(fragment, Fragment, String) 2467 }, 2468 [ fragment(Fragment) ]. 2469uri_fragment(_) --> [].
2476request_header(_, []) --> % Old-style non-version header 2477 blanks, 2478 eos, 2479 !. 2480request_header(Fd, [http_version(Version)|Header]) --> 2481 http_version(Version), 2482 blanks, 2483 eos, 2484 !, 2485 { Version = 1-_ 2486 -> http_read_header(Fd, Header) 2487 ; Header = [] 2488 }. 2489 2490http_version(Version) --> 2491 blanks, 2492 "HTTP/", 2493 http_version_number(Version). 2494 2495http_version_number(Major-Minor) --> 2496 integer(Major), 2497 ".", 2498 integer(Minor). 2499 2500 2501 /******************************* 2502 * COOKIES * 2503 *******************************/
2509cookies([Name=Value|T]) --> 2510 blanks, 2511 cookie(Name, Value), 2512 !, 2513 blanks, 2514 ( ";" 2515 -> cookies(T) 2516 ; { T = [] } 2517 ). 2518cookies(List) --> 2519 string(Skipped), 2520 ";", 2521 !, 2522 { print_message(warning, http(skipped_cookie(Skipped))) }, 2523 cookies(List). 2524cookies([]) --> 2525 blanks. 2526 (Name, Value) --> 2528 cookie_name(Name), 2529 blanks, "=", blanks, 2530 cookie_value(Value). 2531 (Name) --> 2533 { var(Name) }, 2534 !, 2535 rd_field_chars_no_fold(Chars), 2536 { atom_codes(Name, Chars) }. 2537 (Value) --> 2539 quoted_string(Value), 2540 !. 2541cookie_value(Value) --> 2542 chars_to_semicolon_or_blank(Chars), 2543 { atom_codes(Value, Chars) 2544 }. 2545 2546chars_to_semicolon_or_blank([]), ";" --> 2547 ";", 2548 !. 2549chars_to_semicolon_or_blank([]) --> 2550 " ", 2551 blanks, 2552 eos, 2553 !. 2554chars_to_semicolon_or_blank([H|T]) --> 2555 [H], 2556 !, 2557 chars_to_semicolon_or_blank(T). 2558chars_to_semicolon_or_blank([]) --> 2559 []. 2560 (set_cookie(Name, Value, Options)) --> 2562 ws, 2563 cookie(Name, Value), 2564 cookie_options(Options). 2565 ([H|T]) --> 2567 ws, 2568 ";", 2569 ws, 2570 cookie_option(H), 2571 !, 2572 cookie_options(T). 2573cookie_options([]) --> 2574 ws. 2575 2576ws --> " ", !, ws. 2577ws --> [].
Secure and HttpOnly.
2589cookie_option(Name=Value) --> 2590 rd_field_chars(NameChars), ws, 2591 { atom_codes(Name, NameChars) }, 2592 ( "=" 2593 -> ws, 2594 chars_to_semicolon(ValueChars), 2595 { atom_codes(Value, ValueChars) 2596 } 2597 ; { Value = true } 2598 ). 2599 2600chars_to_semicolon([H|T]) --> 2601 [H], 2602 { H \== 32, H \== 0'; }, 2603 !, 2604 chars_to_semicolon(T). 2605chars_to_semicolon([]), ";" --> 2606 ws, ";", 2607 !. 2608chars_to_semicolon([H|T]) --> 2609 [H], 2610 chars_to_semicolon(T). 2611chars_to_semicolon([]) --> 2612 [].
end.2622range(bytes(From, To)) --> 2623 "bytes", whites, "=", whites, integer(From), "-", 2624 ( integer(To) 2625 -> "" 2626 ; { To = end } 2627 ). 2628 2629 2630 /******************************* 2631 * REPLY DCG * 2632 *******************************/
2649reply(Fd, [http_version(HttpVersion), status(Code, Status, Comment)|Header]) --> 2650 http_version(HttpVersion), 2651 blanks, 2652 ( status_number(Status, Code) 2653 -> [] 2654 ; integer(Status) 2655 ), 2656 blanks, 2657 string(CommentCodes), 2658 blanks_to_nl, 2659 !, 2660 blanks, 2661 { atom_codes(Comment, CommentCodes), 2662 http_read_header(Fd, Header) 2663 }. 2664 2665 2666 /******************************* 2667 * READ HEADER * 2668 *******************************/
content_type(text/html)2676http_read_header(Fd, Header) :- 2677 read_header_data(Fd, Text), 2678 http_parse_header(Text, Header). 2679 2680read_header_data(Fd, Header) :- 2681 read_line_to_codes(Fd, Header, Tail), 2682 read_header_data(Header, Fd, Tail), 2683 debug(http(header), 'Header = ~n~s~n', [Header]). 2684 2685read_header_data([0'\r,0'\n], _, _) :- !. 2686read_header_data([0'\n], _, _) :- !. 2687read_header_data([], _, _) :- !. 2688read_header_data(_, Fd, Tail) :- 2689 read_line_to_codes(Fd, Tail, NewTail), 2690 read_header_data(Tail, Fd, NewTail).
2699http_parse_header(Text, Header) :- 2700 phrase(header(Header), Text), 2701 debug(http(header), 'Field: ~p', [Header]). 2702 2703header(List) --> 2704 header_field(Name, Value), 2705 !, 2706 { mkfield(Name, Value, List, Tail) 2707 }, 2708 blanks, 2709 header(Tail). 2710header([]) --> 2711 blanks, 2712 eos, 2713 !. 2714header(_) --> 2715 string(S), blanks_to_nl, 2716 !, 2717 { string_codes(Line, S), 2718 syntax_error(http_parameter(Line)) 2719 }.
SWI-Prolog httpd at <hostname>
The address can be modified by providing a definition for the multifile predicate http:http_address//0.
2733:- multifile 2734 http:http_address//0. 2735 2736address --> 2737 http:http_address, 2738 !. 2739address --> 2740 { gethostname(Host) }, 2741 html(address([ a(href('http://www.swi-prolog.org'), 'SWI-Prolog'), 2742 ' httpd at ', Host 2743 ])). 2744 2745mkfield(host, Host:Port, [host(Host),port(Port)|Tail], Tail) :- !. 2746mkfield(Name, Value, [Att|Tail], Tail) :- 2747 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.
2786 /******************************* 2787 * MESSAGES * 2788 *******************************/ 2789 2790:- multifile 2791 prolog:message//1, 2792 prolog:error_message//1. 2793 2794prologerror_message(http_write_short(Data, Sent)) --> 2795 data(Data), 2796 [ ': remote hangup after ~D bytes'-[Sent] ]. 2797prologerror_message(syntax_error(http_request(Request))) --> 2798 [ 'Illegal HTTP request: ~s'-[Request] ]. 2799prologerror_message(syntax_error(http_parameter(Line))) --> 2800 [ 'Illegal HTTP parameter: ~s'-[Line] ]. 2801 2802prologmessage(http(skipped_cookie(S))) --> 2803 [ 'Skipped illegal cookie: ~s'-[S] ]. 2804 2805data(bytes(MimeType, _Bytes)) --> 2806 !, 2807 [ 'bytes(~p, ...)'-[MimeType] ]. 2808data(Data) --> 2809 [ '~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. */