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) 2002-2024, University of Amsterdam 7 VU University Amsterdam 8 SWI-Prolog Solutions b.v. 9 All rights reserved. 10 11 Redistribution and use in source and binary forms, with or without 12 modification, are permitted provided that the following conditions 13 are met: 14 15 1. Redistributions of source code must retain the above copyright 16 notice, this list of conditions and the following disclaimer. 17 18 2. Redistributions in binary form must reproduce the above copyright 19 notice, this list of conditions and the following disclaimer in 20 the documentation and/or other materials provided with the 21 distribution. 22 23 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24 "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 25 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 26 FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 27 COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 28 INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 29 BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 30 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 31 CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 33 ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 34 POSSIBILITY OF SUCH DAMAGE. 35*/ 36 37:- module(http_header, 38 [ http_read_request/2, % +Stream, -Request 39 http_read_reply_header/2, % +Stream, -Reply 40 http_reply/2, % +What, +Stream 41 http_reply/3, % +What, +Stream, +HdrExtra 42 http_reply/4, % +What, +Stream, +HdrExtra, -Code 43 http_reply/5, % +What, +Stream, +HdrExtra, +Context, 44 % -Code 45 http_reply/6, % +What, +Stream, +HdrExtra, +Context, 46 % +Request, -Code 47 http_reply_header/3, % +Stream, +What, +HdrExtra 48 http_status_reply/4, % +Status, +Out, +HdrExtra, -Code 49 http_status_reply/5, % +Status, +Out, +HdrExtra, 50 % +Context, -Code 51 52 http_timestamp/2, % ?Time, ?HTTPstring 53 54 http_post_data/3, % +Stream, +Data, +HdrExtra 55 56 http_read_header/2, % +Fd, -Header 57 http_parse_header/2, % +Codes, -Header 58 http_parse_header_value/3, % +Header, +HeaderValue, -MediaTypes 59 http_join_headers/3, % +Default, +InHdr, -OutHdr 60 http_update_encoding/3, % +HeaderIn, -Encoding, -HeaderOut 61 http_update_connection/4, % +HeaderIn, +Request, -Connection, -HeaderOut 62 http_update_transfer/4 % +HeaderIn, +Request, -Transfer, -HeaderOut 63 ]). 64:- autoload(html_write, 65 [ print_html/2, print_html/1, page/4, html/3, 66 html_print_length/2 67 ]). 68:- if(exists_source(http_exception)). 69:- autoload(http_exception,[map_exception_to_http_status/4]). 70:- endif. 71:- autoload(mimepack,[mime_pack/3]). 72:- autoload(mimetype,[file_mime_type/2]). 73:- autoload(library(apply),[maplist/2]). 74:- autoload(library(base64),[base64/2]). 75:- use_module(library(debug),[debug/3,debugging/1]). 76:- autoload(library(error),[syntax_error/1,domain_error/2]). 77:- autoload(library(lists),[append/3,member/2,select/3,delete/3]). 78:- autoload(library(memfile), 79 [ new_memory_file/1, open_memory_file/3, 80 free_memory_file/1, open_memory_file/4, 81 size_memory_file/3 82 ]). 83:- autoload(library(option),[option/3,option/2]). 84:- autoload(library(pairs),[pairs_values/2]). 85:- autoload(library(readutil), 86 [read_line_to_codes/2,read_line_to_codes/3]). 87:- autoload(library(sgml_write),[xml_write/3]). 88:- autoload(library(socket),[gethostname/1]). 89:- autoload(library(uri), 90 [ uri_components/2, uri_data/3, uri_encoded/3, uri_query_components/2 91 ]). 92:- autoload(library(url),[parse_url_search/2]). 93:- autoload(library(dcg/basics), 94 [ integer/3, atom/3, whites/2, blanks_to_nl/2, string/3, 95 number/3, blanks/2, float/3, nonblanks/3, eos/2 96 ]). 97:- autoload(library(date), [parse_time/3]). 98:- use_module(library(settings),[setting/4,setting/2]). 99 100:- multifile 101 http:status_page/3, % +Status, +Context, -HTML 102 http:status_reply/3, % +Status, -Reply, +Options 103 http:serialize_reply/2, % +Reply, -Body 104 http:post_data_hook/3, % +Data, +Out, +HdrExtra 105 http:mime_type_encoding/2. % +MimeType, -Encoding 106 107% see http_update_transfer/4. 108 109:- setting(http:chunked_transfer, oneof([never,on_request,if_possible]), 110 on_request, 'When to use Transfer-Encoding: Chunked').
120:- discontiguous 121 term_expansion/2. 122 123 124 /******************************* 125 * READ REQUEST * 126 *******************************/
end_of_file if FdIn is at the end of input.
134http_read_request(In, Request) :-
135 catch(read_line_to_codes(In, Codes), E, true),
136 ( var(E)
137 -> ( Codes == end_of_file
138 -> debug(http(header), 'end-of-file', []),
139 Request = end_of_file
140 ; debug(http(header), 'First line: ~s', [Codes]),
141 Request = [input(In)|Request1],
142 phrase(request(In, Request1), Codes),
143 ( Request1 = [unknown(Text)|_]
144 -> string_codes(S, Text),
145 syntax_error(http_request(S))
146 ; true
147 )
148 )
149 ; ( debugging(http(request))
150 -> message_to_string(E, Msg),
151 debug(http(request), "Exception reading 1st line: ~s", [Msg])
152 ; true
153 ),
154 Request = end_of_file
155 ).163http_read_reply_header(In, [input(In)|Reply]) :- 164 read_line_to_codes(In, Codes), 165 ( Codes == end_of_file 166 -> debug(http(header), 'end-of-file', []), 167 throw(error(syntax(http_reply_header, end_of_file), _)) 168 ; debug(http(header), 'First line: ~s~n', [Codes]), 169 ( phrase(reply(In, Reply), Codes) 170 -> true 171 ; atom_codes(Header, Codes), 172 syntax_error(http_reply_header(Header)) 173 ) 174 ). 175 176 177 /******************************* 178 * FORMULATE REPLY * 179 *******************************/
html_write.plfile, but do not include modification time228http_reply(What, Out) :- 229 http_reply(What, Out, [connection(close)], _). 230 231http_reply(Data, Out, HdrExtra) :- 232 http_reply(Data, Out, HdrExtra, _Code). 233 234http_reply(Data, Out, HdrExtra, Code) :- 235 http_reply(Data, Out, HdrExtra, [], Code). 236 237http_reply(Data, Out, HdrExtra, Context, Code) :- 238 http_reply(Data, Out, HdrExtra, Context, [method(get)], Code). 239 240http_reply(Data, Out, HdrExtra, _Context, Request, Code) :- 241 byte_count(Out, C0), 242 memberchk(method(Method), Request), 243 catch(http_reply_data(Data, Out, HdrExtra, Method, Code), E, true), 244 !, 245 ( var(E) 246 -> true 247 ; ( E = error(io_error(write,_), _) 248 ; E = error(socket_error(_,_), _) 249 ) 250 -> byte_count(Out, C1), 251 Sent is C1 - C0, 252 throw(error(http_write_short(Data, Sent), _)) 253 ; E = error(timeout_error(write, _), _) 254 -> throw(E) 255 ; map_exception_to_http_status(E, Status, NewHdr, NewContext) 256 -> http_status_reply(Status, Out, NewHdr, NewContext, Request, Code) 257 ; throw(E) 258 ). 259http_reply(Status, Out, HdrExtra, Context, Request, Code) :- 260 http_status_reply(Status, Out, HdrExtra, Context, Request, Code). 261 262:- if(\+current_predicate(map_exception_to_http_status/4)). 263map_exception_to_http_status(_E, _Status, _NewHdr, _NewContext) :- 264 fail. 265:- endif. 266 267:- meta_predicate 268 if_no_head(, ).
277http_reply_data(Data, Out, HdrExtra, Method, Code) :- 278 http_reply_data_(Data, Out, HdrExtra, Method, Code), 279 flush_output(Out). 280 281http_reply_data_(html(HTML), Out, HdrExtra, Method, Code) :- 282 !, 283 phrase(reply_header(html(HTML), HdrExtra, Code), Header), 284 send_reply_header(Out, Header), 285 if_no_head(print_html(Out, HTML), Method). 286http_reply_data_(file(Type, File), Out, HdrExtra, Method, Code) :- 287 !, 288 phrase(reply_header(file(Type, File), HdrExtra, Code), Header), 289 reply_file(Out, File, Header, Method). 290http_reply_data_(gzip_file(Type, File), Out, HdrExtra, Method, Code) :- 291 !, 292 phrase(reply_header(gzip_file(Type, File), HdrExtra, Code), Header), 293 reply_file(Out, File, Header, Method). 294http_reply_data_(file(Type, File, Range), Out, HdrExtra, Method, Code) :- 295 !, 296 phrase(reply_header(file(Type, File, Range), HdrExtra, Code), Header), 297 reply_file_range(Out, File, Header, Range, Method). 298http_reply_data_(tmp_file(Type, File), Out, HdrExtra, Method, Code) :- 299 !, 300 phrase(reply_header(tmp_file(Type, File), HdrExtra, Code), Header), 301 reply_file(Out, File, Header, Method). 302http_reply_data_(bytes(Type, Bytes), Out, HdrExtra, Method, Code) :- 303 !, 304 phrase(reply_header(bytes(Type, Bytes), HdrExtra, Code), Header), 305 send_reply_header(Out, Header), 306 if_no_head(format(Out, '~s', [Bytes]), Method). 307http_reply_data_(stream(In, Len), Out, HdrExtra, Method, Code) :- 308 !, 309 phrase(reply_header(cgi_data(Len), HdrExtra, Code), Header), 310 copy_stream(Out, In, Header, Method, 0, end). 311http_reply_data_(cgi_stream(In, Len), Out, HdrExtra, Method, Code) :- 312 !, 313 http_read_header(In, CgiHeader), 314 seek(In, 0, current, Pos), 315 Size is Len - Pos, 316 http_join_headers(HdrExtra, CgiHeader, Hdr2), 317 phrase(reply_header(cgi_data(Size), Hdr2, Code), Header), 318 copy_stream(Out, In, Header, Method, 0, end). 319 320if_no_head(_, head) :- 321 !. 322if_no_head(Goal, _) :- 323 call(Goal). 324 325reply_file(Out, _File, Header, head) :- 326 !, 327 send_reply_header(Out, Header). 328reply_file(Out, File, Header, _) :- 329 setup_call_cleanup( 330 open(File, read, In, [type(binary)]), 331 copy_stream(Out, In, Header, 0, end), 332 close(In)). 333 334reply_file_range(Out, _File, Header, _Range, head) :- 335 !, 336 send_reply_header(Out, Header). 337reply_file_range(Out, File, Header, bytes(From, To), _) :- 338 setup_call_cleanup( 339 open(File, read, In, [type(binary)]), 340 copy_stream(Out, In, Header, From, To), 341 close(In)). 342 343copy_stream(Out, _, Header, head, _, _) :- 344 !, 345 send_reply_header(Out, Header). 346copy_stream(Out, In, Header, _, From, To) :- 347 copy_stream(Out, In, Header, From, To). 348 349copy_stream(Out, In, Header, From, To) :- 350 ( From == 0 351 -> true 352 ; seek(In, From, bof, _) 353 ), 354 peek_byte(In, _), 355 send_reply_header(Out, Header), 356 ( To == end 357 -> copy_stream_data(In, Out) 358 ; Len is To - From, 359 copy_stream_data(In, Out, Len) 360 ).
Status can be one of the following:
basic(Realm)digest(Digest)authorise(basic(Realm)). Deprecated.394http_status_reply(Status, Out, Options) :- 395 _{header:HdrExtra, context:Context, code:Code, method:Method} :< Options, 396 http_status_reply(Status, Out, HdrExtra, Context, [method(Method)], Code). 397 398http_status_reply(Status, Out, HdrExtra, Code) :- 399 http_status_reply(Status, Out, HdrExtra, [], Code). 400 401http_status_reply(Status, Out, HdrExtra, Context, Code) :- 402 http_status_reply(Status, Out, HdrExtra, Context, [method(get)], Code). 403 404http_status_reply(Status, Out, HdrExtra, Context, Request, Code) :- 405 option(method(Method), Request, get), 406 parsed_accept(Request, Accept), 407 status_reply_flush(Status, Out, 408 _{ context: Context, 409 method: Method, 410 code: Code, 411 accept: Accept, 412 header: HdrExtra 413 }). 414 415parsed_accept(Request, Accept) :- 416 memberchk(accept(Accept0), Request), 417 http_parse_header_value(accept, Accept0, Accept1), 418 !, 419 Accept = Accept1. 420parsed_accept(_, [ media(text/html, [], 0.1, []), 421 media(_, [], 0.01, []) 422 ]). 423 424status_reply_flush(Status, Out, Options) :- 425 status_reply(Status, Out, Options), 426 !, 427 flush_output(Out).
440% Replies without content 441status_reply(no_content, Out, Options) :- 442 !, 443 phrase(reply_header(status(no_content), Options), Header), 444 send_reply_header(Out, Header). 445status_reply(switching_protocols(_Goal,SwitchOptions), Out, Options) :- 446 !, 447 ( option(headers(Extra1), SwitchOptions) 448 -> true 449 ; option(header(Extra1), SwitchOptions, []) 450 ), 451 http_join_headers(Options.header, Extra1, HdrExtra), 452 phrase(reply_header(status(switching_protocols), 453 Options.put(header,HdrExtra)), Header), 454 send_reply_header(Out, Header). 455status_reply(authorise(basic, ''), Out, Options) :- 456 !, 457 status_reply(authorise(basic), Out, Options). 458status_reply(authorise(basic, Realm), Out, Options) :- 459 !, 460 status_reply(authorise(basic(Realm)), Out, Options). 461status_reply(not_modified, Out, Options) :- 462 !, 463 phrase(reply_header(status(not_modified), Options), Header), 464 send_reply_header(Out, Header). 465% aliases (compatibility) 466status_reply(busy, Out, Options) :- 467 status_reply(service_unavailable(busy), Out, Options). 468status_reply(unavailable(Why), Out, Options) :- 469 status_reply(service_unavailable(Why), Out, Options). 470status_reply(resource_error(Why), Out, Options) :- 471 status_reply(service_unavailable(Why), Out, Options). 472% replies with content 473status_reply(Status, Out, Options) :- 474 status_has_content(Status), 475 status_page_hook(Status, Reply, Options), 476 serialize_body(Reply, Body), 477 Status =.. List, 478 append(List, [Body], ExList), 479 ExStatus =.. ExList, 480 phrase(reply_header(ExStatus, Options), Header), 481 send_reply_header(Out, Header), 482 reply_status_body(Out, Body, Options).
489status_has_content(created(_Location)). 490status_has_content(moved(_To)). 491status_has_content(moved_temporary(_To)). 492status_has_content(gone(_URL)). 493status_has_content(see_other(_To)). 494status_has_content(bad_request(_ErrorTerm)). 495status_has_content(authorise(_Method)). 496status_has_content(forbidden(_URL)). 497status_has_content(not_found(_URL)). 498status_has_content(method_not_allowed(_Method, _URL)). 499status_has_content(not_acceptable(_Why)). 500status_has_content(server_error(_ErrorTerm)). 501status_has_content(service_unavailable(_Why)).
512serialize_body(Reply, Body) :- 513 http:serialize_reply(Reply, Body), 514 !. 515serialize_body(html_tokens(Tokens), body(text/html, utf8, Content)) :- 516 !, 517 with_output_to(string(Content), print_html(Tokens)). 518serialize_body(Reply, Reply) :- 519 Reply = body(_,_,_), 520 !. 521serialize_body(Reply, _) :- 522 domain_error(http_reply_body, Reply). 523 524reply_status_body(_, _, Options) :- 525 Options.method == head, 526 !. 527reply_status_body(Out, body(_Type, Encoding, Content), _Options) :- 528 ( Encoding == octet 529 -> format(Out, '~s', [Content]) 530 ; setup_call_cleanup( 531 set_stream(Out, encoding(Encoding)), 532 format(Out, '~s', [Content]), 533 set_stream(Out, encoding(octet))) 534 ).
561status_page_hook(Term, Reply, Options) :- 562 Context = Options.context, 563 functor(Term, Name, _), 564 status_number_fact(Name, Code), 565 ( Options.code = Code, 566 http:status_reply(Term, Reply, Options) 567 ; http:status_page(Term, Context, HTML), 568 Reply = html_tokens(HTML) 569 ; http:status_page(Code, Context, HTML), % deprecated 570 Reply = html_tokens(HTML) 571 ), 572 !. 573status_page_hook(created(Location), html_tokens(HTML), _Options) :- 574 phrase(page([ title('201 Created') 575 ], 576 [ h1('Created'), 577 p(['The document was created ', 578 a(href(Location), ' Here') 579 ]), 580 \address 581 ]), 582 HTML). 583status_page_hook(moved(To), html_tokens(HTML), _Options) :- 584 phrase(page([ title('301 Moved Permanently') 585 ], 586 [ h1('Moved Permanently'), 587 p(['The document has moved ', 588 a(href(To), ' Here') 589 ]), 590 \address 591 ]), 592 HTML). 593status_page_hook(moved_temporary(To), html_tokens(HTML), _Options) :- 594 phrase(page([ title('302 Moved Temporary') 595 ], 596 [ h1('Moved Temporary'), 597 p(['The document is currently ', 598 a(href(To), ' Here') 599 ]), 600 \address 601 ]), 602 HTML). 603status_page_hook(gone(URL), html_tokens(HTML), _Options) :- 604 phrase(page([ title('410 Resource Gone') 605 ], 606 [ h1('Resource Gone'), 607 p(['The document has been removed ', 608 a(href(URL), ' from here') 609 ]), 610 \address 611 ]), 612 HTML). 613status_page_hook(see_other(To), html_tokens(HTML), _Options) :- 614 phrase(page([ title('303 See Other') 615 ], 616 [ h1('See Other'), 617 p(['See other document ', 618 a(href(To), ' Here') 619 ]), 620 \address 621 ]), 622 HTML). 623status_page_hook(bad_request(ErrorTerm), html_tokens(HTML), _Options) :- 624 '$messages':translate_message(ErrorTerm, Lines, []), 625 phrase(page([ title('400 Bad Request') 626 ], 627 [ h1('Bad Request'), 628 p(\html_message_lines(Lines)), 629 \address 630 ]), 631 HTML). 632status_page_hook(authorise(_Method), html_tokens(HTML), _Options):- 633 phrase(page([ title('401 Authorization Required') 634 ], 635 [ h1('Authorization Required'), 636 p(['This server could not verify that you ', 637 'are authorized to access the document ', 638 'requested. Either you supplied the wrong ', 639 'credentials (e.g., bad password), or your ', 640 'browser doesn\'t understand how to supply ', 641 'the credentials required.' 642 ]), 643 \address 644 ]), 645 HTML). 646status_page_hook(forbidden(URL), html_tokens(HTML), _Options) :- 647 phrase(page([ title('403 Forbidden') 648 ], 649 [ h1('Forbidden'), 650 p(['You don\'t have permission to access ', URL, 651 ' on this server' 652 ]), 653 \address 654 ]), 655 HTML). 656status_page_hook(not_found(URL), html_tokens(HTML), _Options) :- 657 phrase(page([ title('404 Not Found') 658 ], 659 [ h1('Not Found'), 660 p(['The requested URL ', tt(URL), 661 ' was not found on this server' 662 ]), 663 \address 664 ]), 665 HTML). 666status_page_hook(method_not_allowed(Method,URL), html_tokens(HTML), _Options) :- 667 upcase_atom(Method, UMethod), 668 phrase(page([ title('405 Method not allowed') 669 ], 670 [ h1('Method not allowed'), 671 p(['The requested URL ', tt(URL), 672 ' does not support method ', tt(UMethod), '.' 673 ]), 674 \address 675 ]), 676 HTML). 677status_page_hook(not_acceptable(WhyHTML), html_tokens(HTML), _Options) :- 678 phrase(page([ title('406 Not Acceptable') 679 ], 680 [ h1('Not Acceptable'), 681 WhyHTML, 682 \address 683 ]), 684 HTML). 685status_page_hook(server_error(ErrorTerm), html_tokens(HTML), _Options) :- 686 '$messages':translate_message(ErrorTerm, Lines, []), 687 phrase(page([ title('500 Internal server error') 688 ], 689 [ h1('Internal server error'), 690 p(\html_message_lines(Lines)), 691 \address 692 ]), 693 HTML). 694status_page_hook(service_unavailable(Why), html_tokens(HTML), _Options) :- 695 phrase(page([ title('503 Service Unavailable') 696 ], 697 [ h1('Service Unavailable'), 698 \unavailable(Why), 699 \address 700 ]), 701 HTML). 702 (busy) --> 704 html(p(['The server is temporarily out of resources, ', 705 'please try again later'])). 706unavailable(error(Formal,Context)) --> 707 { '$messages':translate_message(error(Formal,Context), Lines, []) }, 708 html_message_lines(Lines). 709unavailable(HTML) --> 710 html(HTML). 711 712html_message_lines([]) --> 713 []. 714html_message_lines([nl|T]) --> 715 !, 716 html([br([])]), 717 html_message_lines(T). 718html_message_lines([flush]) --> 719 []. 720html_message_lines([ansi(_Style,Fmt,Args)|T]) --> 721 !, 722 { format(string(S), Fmt, Args) 723 }, 724 html([S]), 725 html_message_lines(T). 726html_message_lines([url(Pos)|T]) --> 727 !, 728 msg_url(Pos), 729 html_message_lines(T). 730html_message_lines([url(URL, Label)|T]) --> 731 !, 732 html(a(href(URL), Label)), 733 html_message_lines(T). 734html_message_lines([Fmt-Args|T]) --> 735 !, 736 { format(string(S), Fmt, Args) 737 }, 738 html([S]), 739 html_message_lines(T). 740html_message_lines([Fmt|T]) --> 741 !, 742 { format(string(S), Fmt, []) 743 }, 744 html([S]), 745 html_message_lines(T). 746 747msg_url(File:Line:Pos) --> 748 !, 749 html([File, :, Line, :, Pos]). 750msg_url(File:Line) --> 751 !, 752 html([File, :, Line]). 753msg_url(File) --> 754 html([File]).
761http_join_headers([], H, H). 762http_join_headers([H|T], Hdr0, Hdr) :- 763 functor(H, N, A), 764 functor(H2, N, A), 765 member(H2, Hdr0), 766 !, 767 http_join_headers(T, Hdr0, Hdr). 768http_join_headers([H|T], Hdr0, [H|Hdr]) :- 769 http_join_headers(T, Hdr0, Hdr).
781http_update_encoding(Header0, Encoding, Header) :- 782 memberchk(content_type(Type), Header0), 783 !, 784 http_update_encoding(Type, Header0, Encoding, Header). 785http_update_encoding(Header, octet, Header). 786 787http_update_encoding('text/event-stream', Header, utf8, Header) :- 788 !. 789http_update_encoding(Type0, Header0, utf8, [content_type(Type)|Header]) :- 790 sub_atom(Type0, 0, _, _, 'text/'), 791 !, 792 select(content_type(_), Header0, Header), 793 !, 794 ( sub_atom(Type0, S, _, _, ';') 795 -> sub_atom(Type0, 0, S, _, B) 796 ; B = Type0 797 ), 798 atom_concat(B, '; charset=UTF-8', Type). 799http_update_encoding(Type, Header, Encoding, Header) :- 800 ( sub_atom_icasechk(Type, _, 'utf-8') 801 -> Encoding = utf8 802 ; http:mime_type_encoding(Type, Encoding) 803 -> true 804 ; mime_type_encoding(Type, Encoding) 805 -> true 806 ; Encoding = octet 807 ).
814mime_type_encoding('application/json', utf8). 815mime_type_encoding('application/jsonrequest', utf8). 816mime_type_encoding('application/x-prolog', utf8). 817mime_type_encoding('application/n-quads', utf8). 818mime_type_encoding('application/n-triples', utf8). 819mime_type_encoding('application/sparql-query', utf8). 820mime_type_encoding('application/trig', utf8). 821mime_type_encoding('application/sparql-results+json', utf8). 822mime_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.838http_update_connection(CgiHeader, Request, Connect, 839 [connection(Connect)|Rest]) :- 840 select(connection(CgiConn), CgiHeader, Rest), 841 !, 842 connection(Request, ReqConnection), 843 join_connection(ReqConnection, CgiConn, Connect). 844http_update_connection(CgiHeader, Request, Connect, 845 [connection(Connect)|CgiHeader]) :- 846 connection(Request, Connect). 847 848join_connection(Keep1, Keep2, Connection) :- 849 ( downcase_atom(Keep1, 'keep-alive'), 850 downcase_atom(Keep2, 'keep-alive') 851 -> Connection = 'Keep-Alive' 852 ; Connection = close 853 ).
860connection(Header, Close) :-
861 ( memberchk(connection(Connection), Header)
862 -> Close = Connection
863 ; memberchk(http_version(1-X), Header),
864 X >= 1
865 -> Close = 'Keep-Alive'
866 ; Close = close
867 ).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.
886http_update_transfer(Request, CgiHeader, Transfer, Header) :- 887 setting(http:chunked_transfer, When), 888 http_update_transfer(When, Request, CgiHeader, Transfer, Header). 889 890http_update_transfer(never, _, CgiHeader, none, Header) :- 891 !, 892 delete(CgiHeader, transfer_encoding(_), Header). 893http_update_transfer(_, _, CgiHeader, none, Header) :- 894 memberchk(location(_), CgiHeader), 895 !, 896 delete(CgiHeader, transfer_encoding(_), Header). 897http_update_transfer(_, Request, CgiHeader, Transfer, Header) :- 898 select(transfer_encoding(CgiTransfer), CgiHeader, Rest), 899 !, 900 transfer(Request, ReqConnection), 901 join_transfer(ReqConnection, CgiTransfer, Transfer), 902 ( Transfer == none 903 -> Header = Rest 904 ; Header = [transfer_encoding(Transfer)|Rest] 905 ). 906http_update_transfer(if_possible, Request, CgiHeader, Transfer, Header) :- 907 transfer(Request, Transfer), 908 Transfer \== none, 909 !, 910 Header = [transfer_encoding(Transfer)|CgiHeader]. 911http_update_transfer(_, _, CgiHeader, event_stream, CgiHeader) :- 912 memberchk(content_type('text/event-stream'), CgiHeader), 913 !. 914http_update_transfer(_, _, CgiHeader, none, CgiHeader). 915 916join_transfer(chunked, chunked, chunked) :- !. 917join_transfer(_, _, none).
924transfer(Header, Transfer) :-
925 ( memberchk(transfer_encoding(Transfer0), Header)
926 -> Transfer = Transfer0
927 ; memberchk(http_version(1-X), Header),
928 X >= 1
929 -> Transfer = chunked
930 ; Transfer = none
931 ).940content_length_in_encoding(Enc, Stream, Bytes) :- 941 stream_property(Stream, position(Here)), 942 setup_call_cleanup( 943 open_null_stream(Out), 944 ( set_stream(Out, encoding(Enc)), 945 catch(copy_stream_data(Stream, Out), _, fail), 946 flush_output(Out), 947 byte_count(Out, Bytes) 948 ), 949 ( close(Out, [force(true)]), 950 set_stream_position(Stream, Here) 951 )). 952 953 954 /******************************* 955 * POST SUPPORT * 956 *******************************/
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,
[]),
...,
1064http_post_data(Data, Out, HdrExtra) :- 1065 http:post_data_hook(Data, Out, HdrExtra), 1066 !. 1067http_post_data(html(HTML), Out, HdrExtra) :- 1068 !, 1069 phrase(post_header(html(HTML), HdrExtra), Header), 1070 send_request_header(Out, Header), 1071 print_html(Out, HTML). 1072http_post_data(xml(XML), Out, HdrExtra) :- 1073 !, 1074 http_post_data(xml(text/xml, XML, []), Out, HdrExtra). 1075http_post_data(xml(Type, XML), Out, HdrExtra) :- 1076 !, 1077 http_post_data(xml(Type, XML, []), Out, HdrExtra). 1078http_post_data(xml(Type, XML, Options), Out, HdrExtra) :- 1079 !, 1080 setup_call_cleanup( 1081 new_memory_file(MemFile), 1082 ( setup_call_cleanup( 1083 open_memory_file(MemFile, write, MemOut), 1084 xml_write(MemOut, XML, Options), 1085 close(MemOut)), 1086 http_post_data(memory_file(Type, MemFile), Out, HdrExtra) 1087 ), 1088 free_memory_file(MemFile)). 1089http_post_data(file(File), Out, HdrExtra) :- 1090 !, 1091 ( file_mime_type(File, Type) 1092 -> true 1093 ; Type = text/plain 1094 ), 1095 http_post_data(file(Type, File), Out, HdrExtra). 1096http_post_data(file(Type, File), Out, HdrExtra) :- 1097 !, 1098 phrase(post_header(file(Type, File), HdrExtra), Header), 1099 send_request_header(Out, Header), 1100 setup_call_cleanup( 1101 open(File, read, In, [type(binary)]), 1102 copy_stream_data(In, Out), 1103 close(In)). 1104http_post_data(memory_file(Type, Handle), Out, HdrExtra) :- 1105 !, 1106 phrase(post_header(memory_file(Type, Handle), HdrExtra), Header), 1107 send_request_header(Out, Header), 1108 setup_call_cleanup( 1109 open_memory_file(Handle, read, In, [encoding(octet)]), 1110 copy_stream_data(In, Out), 1111 close(In)). 1112http_post_data(codes(Codes), Out, HdrExtra) :- 1113 !, 1114 http_post_data(codes(text/plain, Codes), Out, HdrExtra). 1115http_post_data(codes(Type, Codes), Out, HdrExtra) :- 1116 !, 1117 phrase(post_header(codes(Type, Codes), HdrExtra), Header), 1118 send_request_header(Out, Header), 1119 setup_call_cleanup( 1120 set_stream(Out, encoding(utf8)), 1121 format(Out, '~s', [Codes]), 1122 set_stream(Out, encoding(octet))). 1123http_post_data(bytes(Type, Bytes), Out, HdrExtra) :- 1124 !, 1125 phrase(post_header(bytes(Type, Bytes), HdrExtra), Header), 1126 send_request_header(Out, Header), 1127 format(Out, '~s', [Bytes]). 1128http_post_data(atom(Atom), Out, HdrExtra) :- 1129 !, 1130 http_post_data(atom(text/plain, Atom), Out, HdrExtra). 1131http_post_data(atom(Type, Atom), Out, HdrExtra) :- 1132 !, 1133 phrase(post_header(atom(Type, Atom), HdrExtra), Header), 1134 send_request_header(Out, Header), 1135 setup_call_cleanup( 1136 set_stream(Out, encoding(utf8)), 1137 write(Out, Atom), 1138 set_stream(Out, encoding(octet))). 1139http_post_data(string(String), Out, HdrExtra) :- 1140 !, 1141 http_post_data(atom(text/plain, String), Out, HdrExtra). 1142http_post_data(string(Type, String), Out, HdrExtra) :- 1143 !, 1144 phrase(post_header(string(Type, String), HdrExtra), Header), 1145 send_request_header(Out, Header), 1146 setup_call_cleanup( 1147 set_stream(Out, encoding(utf8)), 1148 write(Out, String), 1149 set_stream(Out, encoding(octet))). 1150http_post_data(cgi_stream(In, _Len), Out, HdrExtra) :- 1151 !, 1152 debug(obsolete, 'Obsolete 2nd argument in cgi_stream(In,Len)', []), 1153 http_post_data(cgi_stream(In), Out, HdrExtra). 1154http_post_data(cgi_stream(In), Out, HdrExtra) :- 1155 !, 1156 http_read_header(In, Header0), 1157 http_update_encoding(Header0, Encoding, Header), 1158 content_length_in_encoding(Encoding, In, Size), 1159 http_join_headers(HdrExtra, Header, Hdr2), 1160 phrase(post_header(cgi_data(Size), Hdr2), HeaderText), 1161 send_request_header(Out, HeaderText), 1162 setup_call_cleanup( 1163 set_stream(Out, encoding(Encoding)), 1164 copy_stream_data(In, Out), 1165 set_stream(Out, encoding(octet))). 1166http_post_data(form(Fields), Out, HdrExtra) :- 1167 !, 1168 parse_url_search(Codes, Fields), 1169 length(Codes, Size), 1170 http_join_headers(HdrExtra, 1171 [ content_type('application/x-www-form-urlencoded') 1172 ], Header), 1173 phrase(post_header(cgi_data(Size), Header), HeaderChars), 1174 send_request_header(Out, HeaderChars), 1175 format(Out, '~s', [Codes]). 1176http_post_data(form_data(Data), Out, HdrExtra) :- 1177 !, 1178 setup_call_cleanup( 1179 new_memory_file(MemFile), 1180 ( setup_call_cleanup( 1181 open_memory_file(MemFile, write, MimeOut), 1182 mime_pack(Data, MimeOut, Boundary), 1183 close(MimeOut)), 1184 size_memory_file(MemFile, Size, octet), 1185 format(string(ContentType), 1186 'multipart/form-data; boundary=~w', [Boundary]), 1187 http_join_headers(HdrExtra, 1188 [ mime_version('1.0'), 1189 content_type(ContentType) 1190 ], Header), 1191 phrase(post_header(cgi_data(Size), Header), HeaderChars), 1192 send_request_header(Out, HeaderChars), 1193 setup_call_cleanup( 1194 open_memory_file(MemFile, read, In, [encoding(octet)]), 1195 copy_stream_data(In, Out), 1196 close(In)) 1197 ), 1198 free_memory_file(MemFile)). 1199http_post_data(List, Out, HdrExtra) :- % multipart-mixed 1200 is_list(List), 1201 !, 1202 setup_call_cleanup( 1203 new_memory_file(MemFile), 1204 ( setup_call_cleanup( 1205 open_memory_file(MemFile, write, MimeOut), 1206 mime_pack(List, MimeOut, Boundary), 1207 close(MimeOut)), 1208 size_memory_file(MemFile, Size, octet), 1209 format(string(ContentType), 1210 'multipart/mixed; boundary=~w', [Boundary]), 1211 http_join_headers(HdrExtra, 1212 [ mime_version('1.0'), 1213 content_type(ContentType) 1214 ], Header), 1215 phrase(post_header(cgi_data(Size), Header), HeaderChars), 1216 send_request_header(Out, HeaderChars), 1217 setup_call_cleanup( 1218 open_memory_file(MemFile, read, In, [encoding(octet)]), 1219 copy_stream_data(In, Out), 1220 close(In)) 1221 ), 1222 free_memory_file(MemFile)).
1229post_header(html(Tokens), HdrExtra) --> 1230 header_fields(HdrExtra, Len), 1231 content_length(html(Tokens), Len), 1232 content_type(text/html), 1233 "\r\n". 1234post_header(file(Type, File), HdrExtra) --> 1235 header_fields(HdrExtra, Len), 1236 content_length(file(File), Len), 1237 content_type(Type), 1238 "\r\n". 1239post_header(memory_file(Type, File), HdrExtra) --> 1240 header_fields(HdrExtra, Len), 1241 content_length(memory_file(File), Len), 1242 content_type(Type), 1243 "\r\n". 1244post_header(cgi_data(Size), HdrExtra) --> 1245 header_fields(HdrExtra, Len), 1246 content_length(Size, Len), 1247 "\r\n". 1248post_header(codes(Type, Codes), HdrExtra) --> 1249 header_fields(HdrExtra, Len), 1250 content_length(codes(Codes, utf8), Len), 1251 content_type(Type, utf8), 1252 "\r\n". 1253post_header(bytes(Type, Bytes), HdrExtra) --> 1254 header_fields(HdrExtra, Len), 1255 content_length(bytes(Bytes), Len), 1256 content_type(Type), 1257 "\r\n". 1258post_header(atom(Type, Atom), HdrExtra) --> 1259 header_fields(HdrExtra, Len), 1260 content_length(atom(Atom, utf8), Len), 1261 content_type(Type, utf8), 1262 "\r\n". 1263post_header(string(Type, String), HdrExtra) --> 1264 header_fields(HdrExtra, Len), 1265 content_length(string(String, utf8), Len), 1266 content_type(Type, utf8), 1267 "\r\n". 1268 1269 1270 /******************************* 1271 * OUTPUT HEADER DCG * 1272 *******************************/
1279http_reply_header(Out, What, HdrExtra) :-
1280 phrase(reply_header(What, HdrExtra, _Code), String),
1281 !,
1282 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)1306reply_header(Data, Dict) --> 1307 { _{header:HdrExtra, code:Code} :< Dict }, 1308 reply_header(Data, HdrExtra, Code). 1309 1310reply_header(string(String), HdrExtra, Code) --> 1311 reply_header(string(text/plain, String), HdrExtra, Code). 1312reply_header(string(Type, String), HdrExtra, Code) --> 1313 vstatus(ok, Code, HdrExtra), 1314 date(now), 1315 header_fields(HdrExtra, CLen), 1316 content_length(codes(String, utf8), CLen), 1317 content_type(Type, utf8), 1318 "\r\n". 1319reply_header(bytes(Type, Bytes), HdrExtra, Code) --> 1320 vstatus(ok, Code, HdrExtra), 1321 date(now), 1322 header_fields(HdrExtra, CLen), 1323 content_length(bytes(Bytes), CLen), 1324 content_type(Type), 1325 "\r\n". 1326reply_header(html(Tokens), HdrExtra, Code) --> 1327 vstatus(ok, Code, HdrExtra), 1328 date(now), 1329 header_fields(HdrExtra, CLen), 1330 content_length(html(Tokens), CLen), 1331 content_type(text/html), 1332 "\r\n". 1333reply_header(file(Type, File), HdrExtra, Code) --> 1334 vstatus(ok, Code, HdrExtra), 1335 date(now), 1336 modified(file(File)), 1337 header_fields(HdrExtra, CLen), 1338 content_length(file(File), CLen), 1339 content_type(Type), 1340 "\r\n". 1341reply_header(gzip_file(Type, File), HdrExtra, Code) --> 1342 vstatus(ok, Code, HdrExtra), 1343 date(now), 1344 modified(file(File)), 1345 header_fields(HdrExtra, CLen), 1346 content_length(file(File), CLen), 1347 content_type(Type), 1348 content_encoding(gzip), 1349 "\r\n". 1350reply_header(file(Type, File, Range), HdrExtra, Code) --> 1351 vstatus(partial_content, Code, HdrExtra), 1352 date(now), 1353 modified(file(File)), 1354 header_fields(HdrExtra, CLen), 1355 content_length(file(File, Range), CLen), 1356 content_type(Type), 1357 "\r\n". 1358reply_header(tmp_file(Type, File), HdrExtra, Code) --> 1359 vstatus(ok, Code, HdrExtra), 1360 date(now), 1361 header_fields(HdrExtra, CLen), 1362 content_length(file(File), CLen), 1363 content_type(Type), 1364 "\r\n". 1365reply_header(cgi_data(Size), HdrExtra, Code) --> 1366 vstatus(ok, Code, HdrExtra), 1367 date(now), 1368 header_fields(HdrExtra, CLen), 1369 content_length(Size, CLen), 1370 "\r\n". 1371reply_header(event_stream, HdrExtra, Code) --> 1372 vstatus(ok, Code, HdrExtra), 1373 date(now), 1374 header_fields(HdrExtra, _), 1375 "\r\n". 1376reply_header(chunked_data, HdrExtra, Code) --> 1377 vstatus(ok, Code, HdrExtra), 1378 date(now), 1379 header_fields(HdrExtra, _), 1380 ( {memberchk(transfer_encoding(_), HdrExtra)} 1381 -> "" 1382 ; transfer_encoding(chunked) 1383 ), 1384 "\r\n". 1385% non-200 replies without a body (e.g., 1xx, 204, 304) 1386reply_header(status(Status), HdrExtra, Code) --> 1387 vstatus(Status, Code), 1388 header_fields(HdrExtra, Clen), 1389 { Clen = 0 }, 1390 "\r\n". 1391% non-200 replies with a body 1392reply_header(Data, HdrExtra, Code) --> 1393 { status_reply_headers(Data, 1394 body(Type, Encoding, Content), 1395 ReplyHeaders), 1396 http_join_headers(ReplyHeaders, HdrExtra, Headers), 1397 functor(Data, CodeName, _) 1398 }, 1399 vstatus(CodeName, Code, Headers), 1400 date(now), 1401 header_fields(Headers, CLen), 1402 content_length(codes(Content, Encoding), CLen), 1403 content_type(Type, Encoding), 1404 "\r\n". 1405 1406status_reply_headers(created(Location, Body), Body, 1407 [ location(Location) ]). 1408status_reply_headers(moved(To, Body), Body, 1409 [ location(To) ]). 1410status_reply_headers(moved_temporary(To, Body), Body, 1411 [ location(To) ]). 1412status_reply_headers(gone(_URL, Body), Body, []). 1413status_reply_headers(see_other(To, Body), Body, 1414 [ location(To) ]). 1415status_reply_headers(authorise(Method, Body), Body, 1416 [ www_authenticate(Method) ]). 1417status_reply_headers(not_found(_URL, Body), Body, []). 1418status_reply_headers(forbidden(_URL, Body), Body, []). 1419status_reply_headers(method_not_allowed(_Method, _URL, Body), Body, []). 1420status_reply_headers(server_error(_Error, Body), Body, []). 1421status_reply_headers(service_unavailable(_Why, Body), Body, []). 1422status_reply_headers(not_acceptable(_Why, Body), Body, []). 1423status_reply_headers(bad_request(_Error, Body), Body, []).
1431vstatus(_Status, Code, HdrExtra) --> 1432 {memberchk(status(Code), HdrExtra)}, 1433 !, 1434 vstatus(_NewStatus, Code). 1435vstatus(Status, Code, _) --> 1436 vstatus(Status, Code). 1437 1438vstatus(Status, Code) --> 1439 "HTTP/1.1 ", 1440 status_number(Status, Code), 1441 " ", 1442 status_comment(Status), 1443 "\r\n".
1452status_number(Status, Code) --> 1453 { var(Status) }, 1454 !, 1455 integer(Code), 1456 { status_number(Status, Code) }, 1457 !. 1458status_number(Status, Code) --> 1459 { status_number(Status, Code) }, 1460 integer(Code).
1474% Unrecognized status codes that are within a defined code class. 1475% RFC 7231 states: 1476% "[...] a client MUST understand the class of any status code, 1477% as indicated by the first digit, and treat an unrecognized status code 1478% as being equivalent to the `x00` status code of that class [...] 1479% " 1480% @see http://tools.ietf.org/html/rfc7231#section-6 1481 1482status_number(Status, Code) :- 1483 nonvar(Status), 1484 !, 1485 status_number_fact(Status, Code). 1486status_number(Status, Code) :- 1487 nonvar(Code), 1488 !, 1489 ( between(100, 599, Code) 1490 -> ( status_number_fact(Status, Code) 1491 -> true 1492 ; ClassCode is Code // 100 * 100, 1493 status_number_fact(Status, ClassCode) 1494 ) 1495 ; domain_error(http_code, Code) 1496 ). 1497 1498status_number_fact(continue, 100). 1499status_number_fact(switching_protocols, 101). 1500status_number_fact(ok, 200). 1501status_number_fact(created, 201). 1502status_number_fact(accepted, 202). 1503status_number_fact(non_authoritative_info, 203). 1504status_number_fact(no_content, 204). 1505status_number_fact(reset_content, 205). 1506status_number_fact(partial_content, 206). 1507status_number_fact(multiple_choices, 300). 1508status_number_fact(moved, 301). 1509status_number_fact(moved_temporary, 302). 1510status_number_fact(see_other, 303). 1511status_number_fact(not_modified, 304). 1512status_number_fact(use_proxy, 305). 1513status_number_fact(unused, 306). 1514status_number_fact(temporary_redirect, 307). 1515status_number_fact(bad_request, 400). 1516status_number_fact(authorise, 401). 1517status_number_fact(payment_required, 402). 1518status_number_fact(forbidden, 403). 1519status_number_fact(not_found, 404). 1520status_number_fact(method_not_allowed, 405). 1521status_number_fact(not_acceptable, 406). 1522status_number_fact(request_timeout, 408). 1523status_number_fact(conflict, 409). 1524status_number_fact(gone, 410). 1525status_number_fact(length_required, 411). 1526status_number_fact(payload_too_large, 413). 1527status_number_fact(uri_too_long, 414). 1528status_number_fact(unsupported_media_type, 415). 1529status_number_fact(expectation_failed, 417). 1530status_number_fact(upgrade_required, 426). 1531status_number_fact(server_error, 500). 1532status_number_fact(not_implemented, 501). 1533status_number_fact(bad_gateway, 502). 1534status_number_fact(service_unavailable, 503). 1535status_number_fact(gateway_timeout, 504). 1536status_number_fact(http_version_not_supported, 505).
1543status_comment(continue) --> 1544 "Continue". 1545status_comment(switching_protocols) --> 1546 "Switching Protocols". 1547status_comment(ok) --> 1548 "OK". 1549status_comment(created) --> 1550 "Created". 1551status_comment(accepted) --> 1552 "Accepted". 1553status_comment(non_authoritative_info) --> 1554 "Non-Authoritative Information". 1555status_comment(no_content) --> 1556 "No Content". 1557status_comment(reset_content) --> 1558 "Reset Content". 1559status_comment(created) --> 1560 "Created". 1561status_comment(partial_content) --> 1562 "Partial content". 1563status_comment(multiple_choices) --> 1564 "Multiple Choices". 1565status_comment(moved) --> 1566 "Moved Permanently". 1567status_comment(moved_temporary) --> 1568 "Moved Temporary". 1569status_comment(see_other) --> 1570 "See Other". 1571status_comment(not_modified) --> 1572 "Not Modified". 1573status_comment(use_proxy) --> 1574 "Use Proxy". 1575status_comment(unused) --> 1576 "Unused". 1577status_comment(temporary_redirect) --> 1578 "Temporary Redirect". 1579status_comment(bad_request) --> 1580 "Bad Request". 1581status_comment(authorise) --> 1582 "Authorization Required". 1583status_comment(payment_required) --> 1584 "Payment Required". 1585status_comment(forbidden) --> 1586 "Forbidden". 1587status_comment(not_found) --> 1588 "Not Found". 1589status_comment(method_not_allowed) --> 1590 "Method Not Allowed". 1591status_comment(not_acceptable) --> 1592 "Not Acceptable". 1593status_comment(request_timeout) --> 1594 "Request Timeout". 1595status_comment(conflict) --> 1596 "Conflict". 1597status_comment(gone) --> 1598 "Gone". 1599status_comment(length_required) --> 1600 "Length Required". 1601status_comment(payload_too_large) --> 1602 "Payload Too Large". 1603status_comment(uri_too_long) --> 1604 "URI Too Long". 1605status_comment(unsupported_media_type) --> 1606 "Unsupported Media Type". 1607status_comment(expectation_failed) --> 1608 "Expectation Failed". 1609status_comment(upgrade_required) --> 1610 "Upgrade Required". 1611status_comment(server_error) --> 1612 "Internal Server Error". 1613status_comment(not_implemented) --> 1614 "Not Implemented". 1615status_comment(bad_gateway) --> 1616 "Bad Gateway". 1617status_comment(service_unavailable) --> 1618 "Service Unavailable". 1619status_comment(gateway_timeout) --> 1620 "Gateway Timeout". 1621status_comment(http_version_not_supported) --> 1622 "HTTP Version Not Supported". 1623 1624date(Time) --> 1625 "Date: ", 1626 ( { Time == now } 1627 -> now 1628 ; rfc_date(Time) 1629 ), 1630 "\r\n". 1631 1632modified(file(File)) --> 1633 !, 1634 { time_file(File, Time) 1635 }, 1636 modified(Time). 1637modified(Time) --> 1638 "Last-modified: ", 1639 ( { Time == now } 1640 -> now 1641 ; rfc_date(Time) 1642 ), 1643 "\r\n".
1653content_length(file(File, bytes(From, To)), Len) --> 1654 !, 1655 { size_file(File, Size), 1656 ( To == end 1657 -> Len is Size - From, 1658 RangeEnd is Size - 1 1659 ; Len is To+1 - From, % To is index of last byte 1660 RangeEnd = To 1661 ) 1662 }, 1663 content_range(bytes, From, RangeEnd, Size), 1664 content_length(Len, Len). 1665content_length(Reply, Len) --> 1666 { length_of(Reply, Len) 1667 }, 1668 "Content-Length: ", integer(Len), 1669 "\r\n". 1670 1671 1672length_of(_, Len) :- 1673 nonvar(Len), 1674 !. 1675length_of(string(String, Encoding), Len) :- 1676 length_of(codes(String, Encoding), Len). 1677length_of(codes(String, Encoding), Len) :- 1678 !, 1679 setup_call_cleanup( 1680 open_null_stream(Out), 1681 ( set_stream(Out, encoding(Encoding)), 1682 format(Out, '~s', [String]), 1683 byte_count(Out, Len) 1684 ), 1685 close(Out)). 1686length_of(atom(Atom, Encoding), Len) :- 1687 !, 1688 setup_call_cleanup( 1689 open_null_stream(Out), 1690 ( set_stream(Out, encoding(Encoding)), 1691 format(Out, '~a', [Atom]), 1692 byte_count(Out, Len) 1693 ), 1694 close(Out)). 1695length_of(file(File), Len) :- 1696 !, 1697 size_file(File, Len). 1698length_of(memory_file(Handle), Len) :- 1699 !, 1700 size_memory_file(Handle, Len, octet). 1701length_of(html_tokens(Tokens), Len) :- 1702 !, 1703 html_print_length(Tokens, Len). 1704length_of(html(Tokens), Len) :- % deprecated 1705 !, 1706 html_print_length(Tokens, Len). 1707length_of(bytes(Bytes), Len) :- 1708 !, 1709 ( string(Bytes) 1710 -> string_length(Bytes, Len) 1711 ; length(Bytes, Len) % assuming a list of 0..255 1712 ). 1713length_of(Len, Len).
Content-Range header for partial content (206)
replies.1721content_range(Unit, From, RangeEnd, Size) --> 1722 "Content-Range: ", atom(Unit), " ", 1723 integer(From), "-", integer(RangeEnd), "/", integer(Size), 1724 "\r\n". 1725 1726content_encoding(Encoding) --> 1727 "Content-Encoding: ", atom(Encoding), "\r\n". 1728 1729transfer_encoding(Encoding) --> 1730 "Transfer-Encoding: ", atom(Encoding), "\r\n". 1731 1732content_type(Type) --> 1733 content_type(Type, _). 1734 1735content_type(Type, Charset) --> 1736 ctype(Type), 1737 charset(Charset), 1738 "\r\n". 1739 1740ctype(Main/Sub) --> 1741 !, 1742 "Content-Type: ", 1743 atom(Main), 1744 "/", 1745 atom(Sub). 1746ctype(Type) --> 1747 !, 1748 "Content-Type: ", 1749 atom(Type). 1750 1751charset(Var) --> 1752 { var(Var) }, 1753 !. 1754charset(utf8) --> 1755 !, 1756 "; charset=UTF-8". 1757charset(CharSet) --> 1758 "; charset=", 1759 atom(CharSet).
1767header_field(Name, Value) --> 1768 { var(Name) }, % parsing 1769 !, 1770 field_name(Name), 1771 ":", 1772 whites, 1773 read_field_value(ValueChars), 1774 blanks_to_nl, 1775 !, 1776 { field_to_prolog(Name, ValueChars, Value) 1777 -> true 1778 ; atom_codes(Value, ValueChars), 1779 domain_error(Name, Value) 1780 }. 1781header_field(Name, Value) --> 1782 field_name(Name), 1783 ": ", 1784 field_value(Name, Value), 1785 "\r\n".
1791read_field_value([H|T]) --> 1792 [H], 1793 { \+ code_type(H, space) }, 1794 !, 1795 read_field_value(T). 1796read_field_value([]) --> 1797 "". 1798read_field_value([H|T]) --> 1799 [H], 1800 read_field_value(T).
1807send_reply_header(Out, String) :- 1808 debug(http(send_reply), "< ~s", [String]), 1809 format(Out, '~s', [String]). 1810 1811send_request_header(Out, String) :- 1812 debug(http(send_request), "> ~s", [String]), 1813 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.
1855http_parse_header_value(Field, Value, Prolog) :- 1856 known_field(Field, _, Type), 1857 ( already_parsed(Type, Value) 1858 -> Prolog = Value 1859 ; parse_header_value_atom(Field, Value, Prolog) 1860 -> true 1861 ; to_codes(Value, Codes), 1862 parse_header_value(Field, Codes, Prolog) 1863 ). 1864 1865already_parsed(integer, V) :- !, integer(V). 1866already_parsed(list(Type), L) :- !, is_list(L), maplist(already_parsed(Type), L). 1867already_parsed(Term, V) :- subsumes_term(Term, V).
1875known_field(content_length, true, integer). 1876known_field(status, true, integer). 1877known_field(expires, false, number). 1878known_field(cookie, true, list(_=_)). 1879known_field(set_cookie, true, list(set_cookie(_Name,_Value,_Options))). 1880known_field(host, true, _Host:_Port). 1881known_field(range, maybe, bytes(_,_)). 1882known_field(accept, maybe, list(media(_Type, _Parms, _Q, _Exts))). 1883known_field(content_disposition, maybe, disposition(_Name, _Attributes)). 1884known_field(content_type, false, media(_Type/_Sub, _Attributes)). 1885 1886to_codes(In, Codes) :- 1887 ( is_list(In) 1888 -> Codes = In 1889 ; atom_codes(In, Codes) 1890 ).
known_fields(_,true), this must succeed. For maybe, we just
return the atom if the translation fails.1898field_to_prolog(Field, Codes, Prolog) :- 1899 known_field(Field, true, _Type), 1900 !, 1901 ( parse_header_value(Field, Codes, Prolog0) 1902 -> Prolog = Prolog0 1903 ). 1904field_to_prolog(Field, Codes, Prolog) :- 1905 known_field(Field, maybe, _Type), 1906 parse_header_value(Field, Codes, Prolog0), 1907 !, 1908 Prolog = Prolog0. 1909field_to_prolog(_, Codes, Atom) :- 1910 atom_codes(Atom, Codes).
1916parse_header_value_atom(content_length, Atom, ContentLength) :- 1917 atomic(Atom), 1918 atom_number(Atom, ContentLength). 1919parse_header_value_atom(expires, Atom, Stamp) :- 1920 http_timestamp(Stamp, Atom).
1927parse_header_value(content_length, ValueChars, ContentLength) :- 1928 number_codes(ContentLength, ValueChars). 1929parse_header_value(expires, ValueCodes, Stamp) :- 1930 http_timestamp(Stamp, ValueCodes). 1931parse_header_value(status, ValueChars, Code) :- 1932 ( phrase(" ", L, _), 1933 append(Pre, L, ValueChars) 1934 -> number_codes(Code, Pre) 1935 ; number_codes(Code, ValueChars) 1936 ). 1937parse_header_value(cookie, ValueChars, Cookies) :- 1938 debug(cookie, 'Cookie: ~s', [ValueChars]), 1939 phrase(cookies(Cookies), ValueChars). 1940parse_header_value(set_cookie, ValueChars, SetCookie) :- 1941 debug(cookie, 'SetCookie: ~s', [ValueChars]), 1942 phrase(set_cookie(SetCookie), ValueChars). 1943parse_header_value(host, ValueChars, Host) :- 1944 ( append(HostChars, [0':|PortChars], ValueChars), 1945 catch(number_codes(Port, PortChars), _, fail) 1946 -> atom_codes(HostName, HostChars), 1947 Host = HostName:Port 1948 ; atom_codes(Host, ValueChars) 1949 ). 1950parse_header_value(range, ValueChars, Range) :- 1951 phrase(range(Range), ValueChars). 1952parse_header_value(accept, ValueChars, Media) :- 1953 parse_accept(ValueChars, Media). 1954parse_header_value(content_disposition, ValueChars, Disposition) :- 1955 phrase(content_disposition(Disposition), ValueChars). 1956parse_header_value(content_type, ValueChars, Type) :- 1957 phrase(parse_content_type(Type), ValueChars).
1961field_value(_, set_cookie(Name, Value, Options)) --> 1962 !, 1963 atom(Name), "=", atom(Value), 1964 value_options(Options, cookie). 1965field_value(_, disposition(Disposition, Options)) --> 1966 !, 1967 atom(Disposition), value_options(Options, disposition). 1968field_value(www_authenticate, Auth) --> 1969 auth_field_value(Auth). 1970field_value(_, Atomic) --> 1971 atom(Atomic).
1977auth_field_value(negotiate(Data)) --> 1978 "Negotiate ", 1979 { base64(Data, DataBase64), 1980 atom_codes(DataBase64, Codes) 1981 }, 1982 string(Codes). 1983auth_field_value(negotiate) --> 1984 "Negotiate". 1985auth_field_value(basic) --> 1986 !, 1987 "Basic". 1988auth_field_value(basic(Realm)) --> 1989 "Basic Realm=\"", atom(Realm), "\"". 1990auth_field_value(digest) --> 1991 !, 1992 "Digest". 1993auth_field_value(digest(Details)) --> 1994 "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.2003value_options([], _) --> []. 2004value_options([H|T], Field) --> 2005 "; ", value_option(H, Field), 2006 value_options(T, Field). 2007 2008value_option(secure=true, cookie) --> 2009 !, 2010 "secure". 2011value_option(Name=Value, Type) --> 2012 { string_option(Name, Type) }, 2013 !, 2014 atom(Name), "=", 2015 qstring(Value). 2016value_option(Name=Value, Type) --> 2017 { token_option(Name, Type) }, 2018 !, 2019 atom(Name), "=", atom(Value). 2020value_option(Name=Value, _Type) --> 2021 atom(Name), "=", 2022 option_value(Value). 2023 2024string_option(filename, disposition). 2025 2026token_option(path, cookie). 2027 2028option_value(Value) --> 2029 { number(Value) }, 2030 !, 2031 number(Value). 2032option_value(Value) --> 2033 { ( atom(Value) 2034 -> true 2035 ; string(Value) 2036 ), 2037 forall(string_code(_, Value, C), 2038 token_char(C)) 2039 }, 2040 !, 2041 atom(Value). 2042option_value(Atomic) --> 2043 qstring(Atomic). 2044 2045qstring(Atomic) --> 2046 { string_codes(Atomic, Codes) }, 2047 "\"", 2048 qstring_codes(Codes), 2049 "\"". 2050 2051qstring_codes([]) --> []. 2052qstring_codes([H|T]) --> qstring_code(H), qstring_codes(T). 2053 2054qstring_code(C) --> {qstring_esc(C)}, !, "\\", [C]. 2055qstring_code(C) --> [C]. 2056 2057qstring_esc(0'"). 2058qstring_esc(C) :- ctl(C). 2059 2060 2061 /******************************* 2062 * ACCEPT HEADERS * 2063 *******************************/ 2064 2065:- dynamic accept_cache/2. 2066:- volatile accept_cache/2. 2067 2068parse_accept(Codes, Media) :- 2069 atom_codes(Atom, Codes), 2070 ( accept_cache(Atom, Media0) 2071 -> Media = Media0 2072 ; phrase(accept(Media0), Codes), 2073 keysort(Media0, Media1), 2074 pairs_values(Media1, Media2), 2075 assertz(accept_cache(Atom, Media2)), 2076 Media = Media2 2077 ).
2083accept([H|T]) --> 2084 blanks, 2085 media_range(H), 2086 blanks, 2087 ( "," 2088 -> accept(T) 2089 ; {T=[]} 2090 ). 2091 2092media_range(s(SortQuality,Spec)-media(Type, TypeParams, Quality, AcceptExts)) --> 2093 media_type(Type), 2094 blanks, 2095 ( ";" 2096 -> blanks, 2097 parameters_and_quality(TypeParams, Quality, AcceptExts) 2098 ; { TypeParams = [], 2099 Quality = 1.0, 2100 AcceptExts = [] 2101 } 2102 ), 2103 { SortQuality is float(-Quality), 2104 rank_specialised(Type, TypeParams, Spec) 2105 }.
2112content_disposition(disposition(Disposition, Options)) -->
2113 token(Disposition), blanks,
2114 value_parameters(Options).media(Type/SubType,
Parameters).
2121parse_content_type(media(Type, Parameters)) -->
2122 media_type(Type), blanks,
2123 value_parameters(Parameters).2134rank_specialised(Type/SubType, TypeParams, v(VT, VS, SortVP)) :- 2135 var_or_given(Type, VT), 2136 var_or_given(SubType, VS), 2137 length(TypeParams, VP), 2138 SortVP is -VP. 2139 2140var_or_given(V, Val) :- 2141 ( var(V) 2142 -> Val = 0 2143 ; Val = -1 2144 ). 2145 2146media_type(Type/SubType) --> 2147 type(Type), "/", type(SubType). 2148 2149type(_) --> 2150 "*", 2151 !. 2152type(Type) --> 2153 token(Type). 2154 2155parameters_and_quality(Params, Quality, AcceptExts) --> 2156 token(Name), 2157 blanks, "=", blanks, 2158 ( { Name == q } 2159 -> float(Quality), blanks, 2160 value_parameters(AcceptExts), 2161 { Params = [] } 2162 ; { Params = [Name=Value|T] }, 2163 parameter_value(Value), 2164 blanks, 2165 ( ";" 2166 -> blanks, 2167 parameters_and_quality(T, Quality, AcceptExts) 2168 ; { T = [], 2169 Quality = 1.0, 2170 AcceptExts = [] 2171 } 2172 ) 2173 ).
2180value_parameters([H|T]) --> 2181 ";", 2182 !, 2183 blanks, token(Name), blanks, 2184 ( "=" 2185 -> blanks, 2186 ( token(Value) 2187 -> [] 2188 ; quoted_string(Value) 2189 ), 2190 { H = (Name=Value) } 2191 ; { H = Name } 2192 ), 2193 blanks, 2194 value_parameters(T). 2195value_parameters([]) --> 2196 []. 2197 2198parameter_value(Value) --> token(Value), !. 2199parameter_value(Value) --> quoted_string(Value).
2206token(Name) --> 2207 token_char(C1), 2208 token_chars(Cs), 2209 { atom_codes(Name, [C1|Cs]) }. 2210 2211token_chars([H|T]) --> 2212 token_char(H), 2213 !, 2214 token_chars(T). 2215token_chars([]) --> []. 2216 2217token_char(C) :- 2218 \+ ctl(C), 2219 \+ separator_code(C). 2220 2221ctl(C) :- between(0,31,C), !. 2222ctl(127). 2223 2224separator_code(0'(). 2225separator_code(0')). 2226separator_code(0'<). 2227separator_code(0'>). 2228separator_code(0'@). 2229separator_code(0',). 2230separator_code(0';). 2231separator_code(0':). 2232separator_code(0'\\). 2233separator_code(0'"). 2234separator_code(0'/). 2235separator_code(0'[). 2236separator_code(0']). 2237separator_code(0'?). 2238separator_code(0'=). 2239separator_code(0'{). 2240separator_code(0'}). 2241separator_code(0'\s). 2242separator_code(0'\t). 2243 2244term_expansion(token_char(x) --> [x], Clauses) :- 2245 findall((token_char(C)-->[C]), 2246 ( between(0, 255, C), 2247 token_char(C) 2248 ), 2249 Clauses). 2250 2251token_char(x) --> [x].
2257quoted_string(Text) --> 2258 "\"", 2259 quoted_text(Codes), 2260 { atom_codes(Text, Codes) }. 2261 2262quoted_text([]) --> 2263 "\"", 2264 !. 2265quoted_text([H|T]) --> 2266 "\\", !, [H], 2267 quoted_text(T). 2268quoted_text([H|T]) --> 2269 [H], 2270 !, 2271 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.2282header_fields([], _) --> []. 2283header_fields([content_length(CLen)|T], CLen) --> 2284 !, 2285 ( { var(CLen) } 2286 -> "" 2287 ; header_field(content_length, CLen) 2288 ), 2289 header_fields(T, CLen). % Continue or return first only? 2290header_fields([status(_)|T], CLen) --> % handled by vstatus//3. 2291 !, 2292 header_fields(T, CLen). 2293header_fields([H|T], CLen) --> 2294 { H =.. [Name, Value] }, 2295 header_field(Name, Value), 2296 header_fields(T, CLen).
token = 1*<any CHAR except CTLs or separators>
separators = "(" | ")" | "<" | ">" | "@"
| "," | ";" | ":" | "\" | <">
| "/" | "[" | "]" | "?" | "="
| "{" | "}" | SP | HT
2313:- public 2314 field_name//1. 2315 2316field_name(Name) --> 2317 { var(Name) }, 2318 !, 2319 rd_field_chars(Chars), 2320 { atom_codes(Name, Chars) }. 2321field_name(mime_version) --> 2322 !, 2323 "MIME-Version". 2324field_name(www_authenticate) --> 2325 !, 2326 "WWW-Authenticate". 2327field_name(Name) --> 2328 { atom_codes(Name, Chars) }, 2329 wr_field_chars(Chars). 2330 2331rd_field_chars_no_fold([C|T]) --> 2332 [C], 2333 { rd_field_char(C, _) }, 2334 !, 2335 rd_field_chars_no_fold(T). 2336rd_field_chars_no_fold([]) --> 2337 []. 2338 2339rd_field_chars([C0|T]) --> 2340 [C], 2341 { rd_field_char(C, C0) }, 2342 !, 2343 rd_field_chars(T). 2344rd_field_chars([]) --> 2345 [].
2351separators("()<>@,;:\\\"/[]?={} \t"). 2352 2353term_expansion(rd_field_char('expand me',_), Clauses) :- 2354 2355 Clauses = [ rd_field_char(0'-, 0'_) 2356 | Cls 2357 ], 2358 separators(SepString), 2359 string_codes(SepString, Seps), 2360 findall(rd_field_char(In, Out), 2361 ( between(32, 127, In), 2362 \+ memberchk(In, Seps), 2363 In \== 0'-, % 0' 2364 code_type(Out, to_lower(In))), 2365 Cls). 2366 2367rd_field_char('expand me', _). % avoid recursion 2368 2369wr_field_chars([C|T]) --> 2370 !, 2371 { code_type(C, to_lower(U)) }, 2372 [U], 2373 wr_field_chars2(T). 2374wr_field_chars([]) --> 2375 []. 2376 2377wr_field_chars2([]) --> []. 2378wr_field_chars2([C|T]) --> % 0' 2379 ( { C == 0'_ } 2380 -> "-", 2381 wr_field_chars(T) 2382 ; [C], 2383 wr_field_chars2(T) 2384 ).
2390now -->
2391 { get_time(Time)
2392 },
2393 rfc_date(Time).
2400rfc_date(Time, String, Tail) :-
2401 stamp_date_time(Time, Date, 'UTC'),
2402 format_time(codes(String, Tail),
2403 '%a, %d %b %Y %T GMT',
2404 Date, posix).2415http_timestamp(Time, Text), nonvar(Text) => 2416 ( parse_time(Text, _Format, Time0) 2417 -> Time =:= Time0 2418 ; syntax_error(http_timestamp(Text)) 2419 ). 2420http_timestamp(Time, Atom), number(Time) => 2421 stamp_date_time(Time, Date, 'UTC'), 2422 format_time(atom(Atom), 2423 '%a, %d %b %Y %T GMT', 2424 Date, posix). 2425 2426 2427 /******************************* 2428 * REQUEST DCG * 2429 *******************************/ 2430 2431request(Fd, [method(Method),request_uri(ReqURI)|Header]) --> 2432 method(Method), 2433 blanks, 2434 nonblanks(Query), 2435 { atom_codes(ReqURI, Query), 2436 request_uri_parts(ReqURI, Header, Rest) 2437 }, 2438 request_header(Fd, Rest), 2439 !. 2440request(Fd, [unknown(What)|Header]) --> 2441 string(What), 2442 eos, 2443 !, 2444 { http_read_header(Fd, Header) 2445 -> true 2446 ; Header = [] 2447 }. 2448 2449method(get) --> "GET", !. 2450method(put) --> "PUT", !. 2451method(head) --> "HEAD", !. 2452method(post) --> "POST", !. 2453method(delete) --> "DELETE", !. 2454method(patch) --> "PATCH", !. 2455method(options) --> "OPTIONS", !. 2456method(trace) --> "TRACE", !.
2470request_uri_parts(ReqURI, [path(Path)|Parts], Rest) :- 2471 uri_components(ReqURI, Components), 2472 uri_data(path, Components, PathText), 2473 uri_encoded(path, Path, PathText), 2474 phrase(uri_parts(Components), Parts, Rest). 2475 2476uri_parts(Components) --> 2477 uri_search(Components), 2478 uri_fragment(Components). 2479 2480uri_search(Components) --> 2481 { uri_data(search, Components, Search), 2482 nonvar(Search), 2483 catch(uri_query_components(Search, Query), 2484 error(syntax_error(_),_), 2485 fail) 2486 }, 2487 !, 2488 [ search(Query) ]. 2489uri_search(_) --> []. 2490 2491uri_fragment(Components) --> 2492 { uri_data(fragment, Components, String), 2493 nonvar(String), 2494 !, 2495 uri_encoded(fragment, Fragment, String) 2496 }, 2497 [ fragment(Fragment) ]. 2498uri_fragment(_) --> [].
2505request_header(_, []) --> % Old-style non-version header 2506 blanks, 2507 eos, 2508 !. 2509request_header(Fd, [http_version(Version)|Header]) --> 2510 http_version(Version), 2511 blanks, 2512 eos, 2513 !, 2514 { Version = 1-_ 2515 -> http_read_header(Fd, Header) 2516 ; Header = [] 2517 }. 2518 2519http_version(Version) --> 2520 blanks, 2521 "HTTP/", 2522 http_version_number(Version). 2523 2524http_version_number(Major-Minor) --> 2525 integer(Major), 2526 ".", 2527 integer(Minor). 2528 2529 2530 /******************************* 2531 * COOKIES * 2532 *******************************/
2538cookies([Name=Value|T]) --> 2539 blanks, 2540 cookie(Name, Value), 2541 !, 2542 blanks, 2543 ( ";" 2544 -> cookies(T) 2545 ; { T = [] } 2546 ). 2547cookies(List) --> 2548 string(Skipped), 2549 ";", 2550 !, 2551 { print_message(warning, http(skipped_cookie(Skipped))) }, 2552 cookies(List). 2553cookies([]) --> 2554 blanks. 2555 (Name, Value) --> 2557 cookie_name(Name), 2558 blanks, "=", blanks, 2559 cookie_value(Value). 2560 (Name) --> 2562 { var(Name) }, 2563 !, 2564 rd_field_chars_no_fold(Chars), 2565 { atom_codes(Name, Chars) }. 2566 (Value) --> 2568 quoted_string(Value), 2569 !. 2570cookie_value(Value) --> 2571 chars_to_semicolon_or_blank(Chars), 2572 { atom_codes(Value, Chars) 2573 }. 2574 2575chars_to_semicolon_or_blank([]), ";" --> 2576 ";", 2577 !. 2578chars_to_semicolon_or_blank([]) --> 2579 " ", 2580 blanks, 2581 eos, 2582 !. 2583chars_to_semicolon_or_blank([H|T]) --> 2584 [H], 2585 !, 2586 chars_to_semicolon_or_blank(T). 2587chars_to_semicolon_or_blank([]) --> 2588 []. 2589 (set_cookie(Name, Value, Options)) --> 2591 ws, 2592 cookie(Name, Value), 2593 cookie_options(Options). 2594 ([H|T]) --> 2596 ws, 2597 ";", 2598 ws, 2599 cookie_option(H), 2600 !, 2601 cookie_options(T). 2602cookie_options([]) --> 2603 ws. 2604 2605ws --> " ", !, ws. 2606ws --> [].
Secure and HttpOnly.
2618cookie_option(Name=Value) --> 2619 rd_field_chars(NameChars), ws, 2620 { atom_codes(Name, NameChars) }, 2621 ( "=" 2622 -> ws, 2623 chars_to_semicolon(ValueChars), 2624 { atom_codes(Value, ValueChars) 2625 } 2626 ; { Value = true } 2627 ). 2628 2629chars_to_semicolon([H|T]) --> 2630 [H], 2631 { H \== 32, H \== 0'; }, 2632 !, 2633 chars_to_semicolon(T). 2634chars_to_semicolon([]), ";" --> 2635 ws, ";", 2636 !. 2637chars_to_semicolon([H|T]) --> 2638 [H], 2639 chars_to_semicolon(T). 2640chars_to_semicolon([]) --> 2641 [].
end.2651range(bytes(From, To)) --> 2652 "bytes", whites, "=", whites, integer(From), "-", 2653 ( integer(To) 2654 -> "" 2655 ; { To = end } 2656 ). 2657 2658 2659 /******************************* 2660 * REPLY DCG * 2661 *******************************/
2678reply(Fd, [http_version(HttpVersion), status(Code, Status, Comment)|Header]) --> 2679 http_version(HttpVersion), 2680 blanks, 2681 ( status_number(Status, Code) 2682 -> [] 2683 ; integer(Status) 2684 ), 2685 blanks, 2686 string(CommentCodes), 2687 blanks_to_nl, 2688 !, 2689 blanks, 2690 { atom_codes(Comment, CommentCodes), 2691 http_read_header(Fd, Header) 2692 }. 2693 2694 2695 /******************************* 2696 * READ HEADER * 2697 *******************************/
content_type(text/html)2705http_read_header(Fd, Header) :- 2706 read_header_data(Fd, Text), 2707 http_parse_header(Text, Header). 2708 2709read_header_data(Fd, Header) :- 2710 read_line_to_codes(Fd, Header, Tail), 2711 read_header_data(Header, Fd, Tail), 2712 debug(http(header), 'Header = ~n~s~n', [Header]). 2713 2714read_header_data([0'\r,0'\n], _, _) :- !. 2715read_header_data([0'\n], _, _) :- !. 2716read_header_data([], _, _) :- !. 2717read_header_data(_, Fd, Tail) :- 2718 read_line_to_codes(Fd, Tail, NewTail), 2719 read_header_data(Tail, Fd, NewTail).
2728http_parse_header(Text, Header) :- 2729 phrase(header(Header), Text), 2730 debug(http(header), 'Field: ~p', [Header]). 2731 2732header(List) --> 2733 header_field(Name, Value), 2734 !, 2735 { mkfield(Name, Value, List, Tail) 2736 }, 2737 blanks, 2738 header(Tail). 2739header([]) --> 2740 blanks, 2741 eos, 2742 !. 2743header(_) --> 2744 string(S), blanks_to_nl, 2745 !, 2746 { string_codes(Line, S), 2747 syntax_error(http_parameter(Line)) 2748 }.
SWI-Prolog httpd at <hostname>
The address can be modified by providing a definition for the multifile predicate http_address//0.
2762:- multifile 2763 http:http_address//0. 2764 2765address --> 2766 http:http_address, 2767 !. 2768address --> 2769 { gethostname(Host) }, 2770 html(address([ a(href('http://www.swi-prolog.org'), 'SWI-Prolog'), 2771 ' httpd at ', Host 2772 ])). 2773 2774mkfield(host, Host:Port, [host(Host),port(Port)|Tail], Tail) :- !. 2775mkfield(Name, Value, [Att|Tail], Tail) :- 2776 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.
2815 /******************************* 2816 * MESSAGES * 2817 *******************************/ 2818 2819:- multifile 2820 prolog:message//1, 2821 prolog:error_message//1. 2822 2823prologerror_message(http_write_short(Data, Sent)) --> 2824 data(Data), 2825 [ ': remote hangup after ~D bytes'-[Sent] ]. 2826prologerror_message(syntax_error(http_request(Request))) --> 2827 [ 'Illegal HTTP request: ~s'-[Request] ]. 2828prologerror_message(syntax_error(http_parameter(Line))) --> 2829 [ 'Illegal HTTP parameter: ~s'-[Line] ]. 2830 2831prologmessage(http(skipped_cookie(S))) --> 2832 [ 'Skipped illegal cookie: ~s'-[S] ]. 2833 2834data(bytes(MimeType, _Bytes)) --> 2835 !, 2836 [ 'bytes(~p, ...)'-[MimeType] ]. 2837data(Data) --> 2838 [ '~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. */