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) 2003-2017, 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(rdf_db, 37 [ rdf_version/1, % -Version 38 39 rdf/3, % ?Subject, ?Predicate, ?Object 40 rdf/4, % ?Subject, ?Predicate, ?Object, ?DB 41 rdf_has/3, % ?Subject, +Pred, ?Obj 42 rdf_has/4, % ?Subject, +Pred, ?Obj, -RealPred 43 rdf_reachable/3, % ?Subject, +Pred, ?Object 44 rdf_reachable/5, % ?Subject, +Pred, ?Object, +MaxD, ?D 45 rdf_resource/1, % ?Resource 46 rdf_subject/1, % ?Subject 47 48 rdf_member_property/2, % ?Property, ?Index 49 50 rdf_assert/3, % +Subject, +Predicate, +Object 51 rdf_assert/4, % +Subject, +Predicate, +Object, +DB 52 rdf_retractall/3, % ?Subject, ?Predicate, ?Object 53 rdf_retractall/4, % ?Subject, ?Predicate, ?Object, +DB 54 rdf_update/4, % +Subject, +Predicate, +Object, +Act 55 rdf_update/5, % +Subject, +Predicate, +Object, +Src, +Act 56 rdf_set_predicate/2, % +Predicate, +Property 57 rdf_predicate_property/2, % +Predicate, ?Property 58 rdf_current_predicate/1, % -Predicate 59 rdf_current_literal/1, % -Literal 60 rdf_transaction/1, % :Goal 61 rdf_transaction/2, % :Goal, +Id 62 rdf_transaction/3, % :Goal, +Id, +Options 63 rdf_active_transaction/1, % ?Id 64 65 rdf_monitor/2, % :Goal, +Options 66 67 rdf_save_db/1, % +File 68 rdf_save_db/2, % +File, +DB 69 rdf_load_db/1, % +File 70 rdf_reset_db/0, 71 72 rdf_node/1, % -Id 73 rdf_bnode/1, % -Id 74 rdf_is_bnode/1, % +Id 75 76 rdf_is_resource/1, % +Term 77 rdf_is_literal/1, % +Term 78 rdf_literal_value/2, % +Term, -Value 79 80 rdf_load/1, % +File 81 rdf_load/2, % +File, +Options 82 rdf_save/1, % +File 83 rdf_save/2, % +File, +Options 84 rdf_unload/1, % +File 85 rdf_unload_graph/1, % +Graph 86 87 rdf_md5/2, % +DB, -MD5 88 rdf_atom_md5/3, % +Text, +Times, -MD5 89 90 rdf_create_graph/1, % ?Graph 91 rdf_graph_property/2, % ?Graph, ?Property 92 rdf_set_graph/2, % +Graph, +Property 93 rdf_graph/1, % ?Graph 94 rdf_source/1, % ?File 95 rdf_source/2, % ?DB, ?SourceURL 96 rdf_make/0, % Reload modified databases 97 rdf_gc/0, % Garbage collection 98 99 rdf_source_location/2, % +Subject, -Source 100 rdf_statistics/1, % -Key 101 rdf_set/1, % +Term 102 rdf_generation/1, % -Generation 103 rdf_snapshot/1, % -Snapshot 104 rdf_delete_snapshot/1, % +Snapshot 105 rdf_current_snapshot/1, % +Snapshot 106 rdf_estimate_complexity/4, % +S,+P,+O,-Count 107 108 rdf_save_subject/3, % +Stream, +Subject, +DB 109 rdf_save_header/2, % +Out, +Options 110 rdf_save_footer/1, % +Out 111 112 rdf_equal/2, % ?Resource, ?Resource 113 lang_equal/2, % +Lang1, +Lang2 114 lang_matches/2, % +Lang, +Pattern 115 116 rdf_prefix/2, % :Alias, +URI 117 rdf_current_prefix/2, % :Alias, ?URI 118 rdf_register_prefix/2, % +Alias, +URI 119 rdf_register_prefix/3, % +Alias, +URI, +Options 120 rdf_unregister_prefix/1, % +Alias 121 rdf_current_ns/2, % :Alias, ?URI 122 rdf_register_ns/2, % +Alias, +URI 123 rdf_register_ns/3, % +Alias, +URI, +Options 124 rdf_global_id/2, % ?NS:Name, :Global 125 rdf_global_object/2, % +Object, :NSExpandedObject 126 rdf_global_term/2, % +Term, :WithExpandedNS 127 128 rdf_compare/3, % -Dif, +Object1, +Object2 129 rdf_match_label/3, % +How, +String, +Label 130 rdf_split_url/3, % ?Base, ?Local, ?URL 131 rdf_url_namespace/2, % +URL, ?Base 132 133 rdf_warm_indexes/0, 134 rdf_warm_indexes/1, % +Indexed 135 rdf_update_duplicates/0, 136 137 rdf_debug/1, % Set verbosity 138 139 rdf_new_literal_map/1, % -Handle 140 rdf_destroy_literal_map/1, % +Handle 141 rdf_reset_literal_map/1, % +Handle 142 rdf_insert_literal_map/3, % +Handle, +Key, +Literal 143 rdf_insert_literal_map/4, % +Handle, +Key, +Literal, -NewKeys 144 rdf_delete_literal_map/3, % +Handle, +Key, +Literal 145 rdf_delete_literal_map/2, % +Handle, +Key 146 rdf_find_literal_map/3, % +Handle, +KeyList, -Literals 147 rdf_keys_in_literal_map/3, % +Handle, +Spec, -Keys 148 rdf_statistics_literal_map/2, % +Handle, +Name(-Arg...) 149 150 rdf_graph_prefixes/2, % ?Graph, -Prefixes 151 rdf_graph_prefixes/3, % ?Graph, -Prefixes, :Filter 152 153 (rdf_meta)/1, % +Heads 154 op(1150, fx, (rdf_meta)) 155 ]). 156:- use_module(library(rdf)). 157:- use_module(library(lists)). 158:- use_module(library(shlib)). 159:- use_module(library(gensym)). 160:- use_module(library(sgml)). 161:- use_module(library(sgml_write)). 162:- use_module(library(option)). 163:- use_module(library(error)). 164:- use_module(library(uri)). 165:- use_module(library(debug)). 166:- use_module(library(apply)). 167:- use_module(library(xsdp_types)). 168:- if(exists_source(library(thread))). 169:- use_module(library(thread)). 170:- endif. 171:- use_module(library(semweb/rdf_cache)). 172:- use_module(library(semweb/rdf_prefixes)). 173 174:- use_foreign_library(foreign(rdf_db)). 175:- public rdf_print_predicate_cloud/2. % print matrix of reachable predicates 176 177:- meta_predicate 178 rdf_transaction(), 179 rdf_transaction(, ), 180 rdf_transaction(, , ), 181 rdf_monitor(, ), 182 rdf_save(, ), 183 rdf_load(, ). 184 185:- predicate_options(rdf_graph_prefixes/3, 3, 186 [expand(callable), filter(callable), min_count(nonneg)]). 187:- predicate_options(rdf_load/2, 2, 188 [ base_uri(atom), 189 cache(boolean), 190 concurrent(positive_integer), 191 db(atom), 192 format(oneof([xml,triples,turtle,trig,nquads,ntriples])), 193 graph(atom), 194 if(oneof([true,changed,not_loaded])), 195 modified(-float), 196 prefixes(-list), 197 silent(boolean), 198 register_namespaces(boolean) 199 ]). 200:- predicate_options(rdf_save/2, 2, 201 [ graph(atom), 202 db(atom), 203 anon(boolean), 204 base_uri(atom), 205 write_xml_base(boolean), 206 convert_typed_literal(callable), 207 encoding(encoding), 208 document_language(atom), 209 namespaces(list(atom)), 210 xml_attributes(boolean), 211 inline(boolean) 212 ]). 213:- predicate_options(rdf_save_header/2, 2, 214 [ graph(atom), 215 db(atom), 216 namespaces(list(atom)) 217 ]). 218:- predicate_options(rdf_save_subject/3, 3, 219 [ graph(atom), 220 base_uri(atom), 221 convert_typed_literal(callable), 222 document_language(atom) 223 ]). 224:- predicate_options(rdf_transaction/3, 3, 225 [ snapshot(any) 226 ]). 227 228:- discontiguous 229 term_expansion/2.
245 /******************************* 246 * PREFIXES * 247 *******************************/ 248 249% the ns/2 predicate is historically defined in this module. We'll keep 250% that for compatibility reasons. 251 252:- multifile ns/2. 253:- dynamic ns/2. % ID, URL 254 255:- multifile 256 rdf_prefixes:rdf_empty_prefix_cache/2. 257 258rdf_prefixesrdf_empty_prefix_cache(_Prefix, _IRI) :- 259 rdf_empty_prefix_cache. 260 261:- rdf_meta 262 rdf(r,r,o), 263 rdf_has(r,r,o,r), 264 rdf_has(r,r,o), 265 rdf_assert(r,r,o), 266 rdf_retractall(r,r,o), 267 rdf(r,r,o,?), 268 rdf_assert(r,r,o,+), 269 rdf_retractall(r,r,o,?), 270 rdf_reachable(r,r,o), 271 rdf_reachable(r,r,o,+,?), 272 rdf_update(r,r,o,t), 273 rdf_update(r,r,o,+,t), 274 rdf_equal(o,o), 275 rdf_source_location(r,-), 276 rdf_resource(r), 277 rdf_subject(r), 278 rdf_create_graph(r), 279 rdf_graph(r), 280 rdf_graph_property(r,?), 281 rdf_set_graph(r,+), 282 rdf_unload_graph(r), 283 rdf_set_predicate(r, t), 284 rdf_predicate_property(r, -), 285 rdf_estimate_complexity(r,r,r,-), 286 rdf_print_predicate_cloud(r,+).
292rdf_equal(Resource, Resource).300lang_equal(Lang, Lang) :- !. 301lang_equal(Lang1, Lang2) :- 302 downcase_atom(Lang1, LangCannon), 303 downcase_atom(Lang2, LangCannon).
315 /******************************* 316 * BASIC TRIPLE QUERIES * 317 *******************************/
literal(Value) if the
object is a literal value. If a value of the form
NameSpaceID:LocalName is provided it is expanded to a ground
atom using expand_goal/2. This implies you can use this
construct in compiled code without paying a performance penalty.
Literal values take one of the following forms:
rdf:datatype
TypeID. The Value is either the textual representation or a
natural Prolog representation. See the option
convert_typed_literal(:Convertor) of the parser. The storage
layer provides efficient handling of atoms, integers (64-bit)
and floats (native C-doubles). All other data is represented
as a Prolog record.
For literal querying purposes, Object can be of the form
literal(+Query, -Value), where Query is one of the terms below.
If the Query takes a literal argument and the value has a
numeric type numerical comparison is performed.
icase(Text). Backward compatibility.
Backtracking never returns duplicate triples. Duplicates can be
retrieved using rdf/4. The predicate rdf/3 raises a type-error
if called with improper arguments. If rdf/3 is called with a
term literal(_) as Subject or Predicate object it fails
silently. This allows for graph matching goals like
rdf(S,P,O),rdf(O,P2,O2) to proceed without errors.
rdf(Subject, Predicate, Object) is true
exploiting the rdfs:subPropertyOf predicate as well as inverse
predicates declared using rdf_set_predicate/2 with the
inverse_of property.inverse_of(Pred).symetric(true) or inverse_of(P2) properties.
If used with either Subject or Object unbound, it first returns the origin, followed by the reachable nodes in breath-first search-order. The implementation internally looks one solution ahead and succeeds deterministically on the last solution. This predicate never generates the same node twice and is robust against cycles in the transitive relation.
With all arguments instantiated, it succeeds deterministically if a path can be found from Subject to Object. Searching starts at Subject, assuming the branching factor is normally lower. A call with both Subject and Object unbound raises an instantiation error. The following example generates all subclasses of rdfs:Resource:
?- rdf_reachable(X, rdfs:subClassOf, rdfs:'Resource'). X = 'http://www.w3.org/2000/01/rdf-schema#Resource' ; X = 'http://www.w3.org/2000/01/rdf-schema#Class' ; X = 'http://www.w3.org/1999/02/22-rdf-syntax-ns#Property' ; ...
infinite to impose no
distance-limit.
483rdf_subject(Resource) :-
484 rdf_resource(Resource),
485 ( rdf(Resource, _, _) -> true ).This predicate is primarily intended as a way to process all resources without processing resources twice. The user must be aware that some of the returned resources may not appear in any visible triple.
498 /******************************* 499 * TRIPLE MODIFICATIONS * 500 *******************************/
user. Subject and Predicate are
resources. Object is either a resource or a term literal(Value).
See rdf/3 for an explanation of Value for typed and language
qualified literals. All arguments are subject to name-space
expansion. Complete duplicates (including the same graph and
`line' and with a compatible `lifespan') are not added to the
database.literal(Value).552 /******************************* 553 * COLLECTIONS * 554 *******************************/
560term_expansion(member_prefix(x), 561 member_prefix(Prefix)) :- 562 rdf_db:ns(rdf, NS), 563 atom_concat(NS, '_', Prefix). 564member_prefix(x). 565 566rdf_member_property(P, N) :- 567 integer(N), 568 !, 569 member_prefix(Prefix), 570 atom_concat(Prefix, N, P). 571rdf_member_property(P, N) :- 572 member_prefix(Prefix), 573 atom_concat(Prefix, Sub, P), 574 atom_number(Sub, N). 575 576 577 /******************************* 578 * ANONYMOUS SUBJECTS * 579 *******************************/
587rdf_node(Resource) :-
588 rdf_bnode(Resource).594rdf_bnode(Value) :- 595 repeat, 596 gensym('_:genid', Value), 597 \+ rdf(Value, _, _), 598 \+ rdf(_, _, Value), 599 \+ rdf(_, Value, _), 600 !. 601 602 603 604 /******************************* 605 * TYPES * 606 *******************************/
_:. For backward compatibility reason, __ is also
considered to be a blank node.
625rdf_is_resource(Term) :-
626 atom(Term).633rdf_is_literal(literal(Value)) :- 634 ground(Value). 635 636 /******************************* 637 * LITERALS * 638 *******************************/
| Plain literals | Atom |
| Language tagged literal | Atom holding plain text |
| xsd:string | Atom |
| rdf:XMLLiteral | XML DOM Tree |
| Numeric XSD type | Number |
663:- rdf_meta 664 rdf_literal_value(o, -), 665 typed_value(r, +, -), 666 numeric_value(r, +, -). 667 668rdf_literal_value(literal(String), Value) :- 669 atom(String), 670 !, 671 Value = String. 672rdf_literal_value(literal(lang(_Lang, String)), String). 673rdf_literal_value(literal(type(Type, String)), Value) :- 674 typed_value(Type, String, Value). 675 676typed_value(Numeric, String, Value) :- 677 xsdp_numeric_uri(Numeric, NumType), 678 !, 679 numeric_value(NumType, String, Value). 680typed_value(xsd:string, String, String). 681typed_value(rdf:'XMLLiteral', Value, DOM) :- 682 ( atom(Value) 683 -> setup_call_cleanup( 684 ( atom_to_memory_file(Value, MF), 685 open_memory_file(MF, read, In, [free_on_close(true)]) 686 ), 687 load_structure(stream(In), DOM, [dialect(xml)]), 688 close(In)) 689 ; DOM = Value 690 ). 691 692numeric_value(xsd:integer, String, Value) :- 693 atom_number(String, Value), 694 integer(Value). 695numeric_value(xsd:float, String, Value) :- 696 atom_number(String, Number), 697 Value is float(Number). 698numeric_value(xsd:double, String, Value) :- 699 atom_number(String, Number), 700 Value is float(Number). 701numeric_value(xsd:decimal, String, Value) :- 702 atom_number(String, Value). 703 704 705 /******************************* 706 * SOURCE * 707 *******************************/
715rdf_source_location(Subject, Source) :- 716 findall(Source, rdf(Subject, _, _, Source), Sources), 717 sort(Sources, Unique), 718 member(Source, Unique). 719 720 721 /******************************* 722 * GARBAGE COLLECT * 723 *******************************/
729:- public 730 rdf_create_gc_thread/0. 731 732rdf_create_gc_thread :- 733 thread_create(rdf_gc_loop, _, 734 [ alias('__rdf_GC') 735 ]).
742rdf_gc_loop :- 743 catch(rdf_gc_loop(0), E, recover_gc(E)). 744 745recover_gc('$aborted') :- 746 !, 747 thread_self(Me), 748 thread_detach(Me). 749recover_gc(Error) :- 750 print_message(error, Error), 751 rdf_gc_loop. 752 753rdf_gc_loop(CPU) :- 754 repeat, 755 ( consider_gc(CPU) 756 -> rdf_gc(CPU1), 757 sleep(CPU1) 758 ; sleep(0.1) 759 ), 760 fail.
768rdf_gc(CPU) :-
769 statistics(cputime, CPU0),
770 ( rdf_gc_
771 -> statistics(cputime, CPU1),
772 CPU is CPU1-CPU0,
773 rdf_add_gc_time(CPU)
774 ; CPU = 0.0
775 ).__rdf_GC performs garbage collection as long as
it is considered `useful'.
Using rdf_gc/0 should only be needed to ensure a fully clean database for analysis purposes such as leak detection.
787rdf_gc :- 788 has_garbage, 789 !, 790 rdf_gc(_), 791 rdf_gc. 792rdf_gc.
798has_garbage :- 799 rdf_gc_info_(Info), 800 has_garbage(Info), 801 !. 802 803has_garbage(Info) :- arg(2, Info, Garbage), Garbage > 0. 804has_garbage(Info) :- arg(3, Info, Reindexed), Reindexed > 0. 805has_garbage(Info) :- arg(4, Info, Optimizable), Optimizable > 0.
812consider_gc(_CPU) :- 813 ( rdf_gc_info_(gc_info(Triples, % Total #triples in DB 814 Garbage, % Garbage triples in DB 815 Reindexed, % Reindexed & not reclaimed 816 Optimizable, % Non-optimized tables 817 _KeepGen, % Oldest active generation 818 _LastGCGen, % Oldest active gen at last GC 819 _ReindexGen, 820 _LastGCReindexGen)) 821 -> ( (Garbage+Reindexed) * 5 > Triples 822 ; Optimizable > 4 823 ) 824 ; print_message(error, rdf(invalid_gc_info)), 825 sleep(10) 826 ), 827 !. 828 829 830 /******************************* 831 * STATISTICS * 832 *******************************/
triples for the interpretation of this value.878rdf_statistics(graphs(Count)) :- 879 rdf_statistics_(graphs(Count)). 880rdf_statistics(triples(Count)) :- 881 rdf_statistics_(triples(Count)). 882rdf_statistics(duplicates(Count)) :- 883 rdf_statistics_(duplicates(Count)). 884rdf_statistics(lingering(Count)) :- 885 rdf_statistics_(lingering(Count)). 886rdf_statistics(resources(Count)) :- 887 rdf_statistics_(resources(Count)). 888rdf_statistics(properties(Count)) :- 889 rdf_statistics_(predicates(Count)). 890rdf_statistics(literals(Count)) :- 891 rdf_statistics_(literals(Count)). 892rdf_statistics(gc(Count, Reclaimed, Reindexed, Time)) :- 893 rdf_statistics_(gc(Count, Reclaimed, Reindexed, Time)). 894rdf_statistics(searched_nodes(Count)) :- 895 rdf_statistics_(searched_nodes(Count)). 896rdf_statistics(lookup(Index, Count)) :- 897 functor(Indexed, indexed, 16), 898 rdf_statistics_(Indexed), 899 index(Index, I), 900 Arg is I + 1, 901 arg(Arg, Indexed, Count), 902 Count \== 0. 903rdf_statistics(hash_quality(Index, Size, Quality,Optimize)) :- 904 rdf_statistics_(hash_quality(List)), 905 member(hash(Place,Size,Quality,Optimize), List), 906 index(Index, Place). 907rdf_statistics(triples_by_graph(Graph, Count)) :- 908 rdf_graph_(Graph, Count). 909 910index(rdf(-,-,-,-), 0). 911index(rdf(+,-,-,-), 1). 912index(rdf(-,+,-,-), 2). 913index(rdf(+,+,-,-), 3). 914index(rdf(-,-,+,-), 4). 915index(rdf(+,-,+,-), 5). 916index(rdf(-,+,+,-), 6). 917index(rdf(+,+,+,-), 7). 918 919index(rdf(-,-,-,+), 8). 920index(rdf(+,-,-,+), 9). 921index(rdf(-,+,-,+), 10). 922index(rdf(+,+,-,+), 11). 923index(rdf(-,-,+,+), 12). 924index(rdf(+,-,+,+), 13). 925index(rdf(-,+,+,+), 14). 926index(rdf(+,+,+,+), 15). 927 928 929 /******************************* 930 * PREDICATES * 931 *******************************/
Note that resources that have rdf:type rdf:Property are
not automatically included in the result-set of this predicate,
while all resources that appear as the second argument of a
triple are included.
947rdf_current_predicate(P, DB) :-
948 rdf_current_predicate(P),
949 ( rdf(_,P,_,DB)
950 -> true
951 ).inverse_of(Self).rdf_subject_branch_factor, but also considering
triples of `subPropertyOf' this relation. See also rdf_has/3.rdf_object_branch_factor, but also considering
triples of `subPropertyOf' this relation. See also rdf_has/3.1004rdf_predicate_property(P, Prop) :- 1005 var(P), 1006 !, 1007 rdf_current_predicate(P), 1008 rdf_predicate_property_(P, Prop). 1009rdf_predicate_property(P, Prop) :- 1010 rdf_predicate_property_(P, Prop).
symmetric(true) is the same as inverse_of(Predicate),
i.e., creating a predicate that is the inverse of
itself.inverse_of([]).
The transitive property is currently not used. The symmetric
and inverse_of properties are considered by rdf_has/3,4 and
rdf_reachable/3.
1035 /******************************* 1036 * SNAPSHOTS * 1037 *******************************/
snapshot option. A
snapshot created outside a transaction exists until it is
deleted. Snapshots taken inside a transaction can only be used
inside this transaction.1060rdf_current_snapshot(Term) :- 1061 current_blob(Term, rdf_snapshot). 1062 1063 1064 /******************************* 1065 * TRANSACTION * 1066 *******************************/
rdf_transaction(Goal, user, []). See rdf_transaction/3.rdf_transaction(Goal, Id, []). See rdf_transaction/3.library(semweb/rdf_persistency).Processed options are:
true, which implies that an anonymous snapshot is
created at the current state of the store. Modifications
due to executing Goal are only visible to Goal.1102rdf_transaction(Goal) :- 1103 rdf_transaction(Goal, user, []). 1104rdf_transaction(Goal, Id) :- 1105 rdf_transaction(Goal, Id, []).
1116rdf_active_transaction(Id) :-
1117 rdf_active_transactions_(List),
1118 member(Id, List).1124rdf_monitor(Goal, Options) :- 1125 monitor_mask(Options, 0xffff, Mask), 1126 rdf_monitor_(Goal, Mask). 1127 1128monitor_mask([], Mask, Mask). 1129monitor_mask([H|T], Mask0, Mask) :- 1130 update_mask(H, Mask0, Mask1), 1131 monitor_mask(T, Mask1, Mask). 1132 1133update_mask(-X, Mask0, Mask) :- 1134 !, 1135 monitor_mask(X, M), 1136 Mask is Mask0 /\ \M. 1137update_mask(+X, Mask0, Mask) :- 1138 !, 1139 monitor_mask(X, M), 1140 Mask is Mask0 \/ M. 1141update_mask(X, Mask0, Mask) :- 1142 monitor_mask(X, M), 1143 Mask is Mask0 \/ M.
1150 % C-defined broadcasts 1151monitor_mask(assert, 0x0001). 1152monitor_mask(assert(load), 0x0002). 1153monitor_mask(retract, 0x0004). 1154monitor_mask(update, 0x0008). 1155monitor_mask(new_literal, 0x0010). 1156monitor_mask(old_literal, 0x0020). 1157monitor_mask(transaction, 0x0040). 1158monitor_mask(load, 0x0080). 1159monitor_mask(create_graph, 0x0100). 1160monitor_mask(reset, 0x0200). 1161 % prolog defined broadcasts 1162monitor_mask(parse, 0x1000). 1163monitor_mask(unload, 0x1000). % FIXME: Duplicate 1164 % mask for all 1165monitor_mask(all, 0xffff). 1166 1167%rdf_broadcast(Term, MaskName) :- 1168%% monitor_mask(MaskName, Mask), 1169%% rdf_broadcast_(Term, Mask). 1170 1171 1172 /******************************* 1173 * WARM * 1174 *******************************/
1180rdf_warm_indexes :- 1181 findall(Index, rdf_index(Index), Indexes), 1182 rdf_warm_indexes(Indexes). 1183 1184rdf_index(s). 1185rdf_index(p). 1186rdf_index(o). 1187rdf_index(sp). 1188rdf_index(o). 1189rdf_index(po). 1190rdf_index(spo). 1191rdf_index(g). 1192rdf_index(sg). 1193rdf_index(pg).
1204 /******************************* 1205 * DUPLICATES * 1206 *******************************/
The duplicates marks are used to reduce the administrative load of avoiding duplicate answers. Normally, the duplicates are marked using a background thread that is started on the first query that produces a substantial amount of duplicates.
1221:- public
1222 rdf_update_duplicates_thread/0.
1228rdf_update_duplicates_thread :-
1229 thread_create(rdf_update_duplicates, _,
1230 [ detached(true),
1231 alias('__rdf_duplicate_detecter')
1232 ]).This predicate is normally executed from a background thread named =__rdf_duplicate_detecter= which is created when a query discovers that checking for duplicates becomes too expensive.
1246 /******************************* 1247 * QUICK BINARY LOAD/SAVE * 1248 *******************************/
1258:- create_prolog_flag(rdf_triple_format, 3, [type(integer)]). 1259 1260rdf_save_db(File) :- 1261 current_prolog_flag(rdf_triple_format, Version), 1262 setup_call_cleanup( 1263 open(File, write, Out, [type(binary)]), 1264 ( set_stream(Out, record_position(false)), 1265 rdf_save_db_(Out, _, Version) 1266 ), 1267 close(Out)). 1268 1269 1270rdf_save_db(File, Graph) :- 1271 current_prolog_flag(rdf_triple_format, Version), 1272 setup_call_cleanup( 1273 open(File, write, Out, [type(binary)]), 1274 ( set_stream(Out, record_position(false)), 1275 rdf_save_db_(Out, Graph, Version) 1276 ), 1277 close(Out)).
1286rdf_load_db_no_admin(File, Id, Graphs) :-
1287 open(File, read, In, [type(binary)]),
1288 set_stream(In, record_position(false)),
1289 call_cleanup(rdf_load_db_(In, Id, Graphs), close(In)).1300check_loaded_cache(DB, [DB], _Modified) :- !. 1301check_loaded_cache(DB, Graphs, _) :- 1302 print_message(warning, rdf(inconsistent_cache(DB, Graphs))).
1309rdf_load_db(File) :- 1310 uri_file_name(URL, File), 1311 rdf_load_db_no_admin(File, URL, _Graphs). 1312 1313 1314 /******************************* 1315 * LOADING RDF * 1316 *******************************/ 1317 1318:- multifile 1319 rdf_open_hook/8, 1320 rdf_open_decode/4, % +Encoding, +File, -Stream, -Cleanup 1321 rdf_load_stream/3, % +Format, +Stream, +Options 1322 rdf_file_type/2, % ?Extension, ?Format 1323 rdf_storage_encoding/2, % ?Extension, ?Encoding 1324 url_protocol/1. % ?Protocol
rdf_load(FileOrList, []). See rdf_load/2.share (default),
equivalent blank nodes are shared in the same resource.library(semweb/turtle) extend the set of recognised
extensions.true, changed (default) or
not_loaded.not_modified, cached(File),
last_modified(Stamp) or unknown.false, do not use or create a cache file.true (default false), register xmlns namespace
declarations or Turtle @prefix prefixes using
rdf_register_prefix/3 if there is no conflict.true, the message reporting completion is printed using
level silent. Otherwise the level is informational. See
also print_message/2.Other options are forwarded to process_rdf/3. By default, rdf_load/2 only loads RDF/XML from files. It can be extended to load data from other formats and locations using plugins. The full set of plugins relevant to support different formats and locations is below:
:- use_module(library(semweb/turtle)). % Turtle and TriG :- use_module(library(semweb/rdf_ntriples)). :- use_module(library(semweb/rdf_zlib_plugin)). :- use_module(library(semweb/rdf_http_plugin)). :- use_module(library(http/http_ssl_plugin)).
1410:- dynamic 1411 rdf_loading/3. % Graph, Queue, Thread 1412 1413rdf_load(Spec) :- 1414 rdf_load(Spec, []). 1415 1416:- if(\+current_predicate(concurrent/3)). 1417concurrent(_, Goals, _) :- 1418 forall(member(G, Goals), call(G)). 1419:- endif. 1420 1421% Note that we kill atom garbage collection. This improves performance 1422% with about 15% loading the LUBM Univ_50 benchmark. 1423 1424rdf_load(Spec, M:Options) :- 1425 must_be(list, Options), 1426 current_prolog_flag(agc_margin, Old), 1427 setup_call_cleanup( 1428 set_prolog_flag(agc_margin, 0), 1429 rdf_load_noagc(Spec, M, Options), 1430 set_prolog_flag(agc_margin, Old)). 1431 1432rdf_load_noagc(List, M, Options) :- 1433 is_list(List), 1434 !, 1435 flatten(List, Inputs), % Compatibility: allow nested lists 1436 maplist(must_be(ground), Inputs), 1437 length(Inputs, Count), 1438 load_jobs(Count, Jobs, Options), 1439 ( Jobs =:= 1 1440 -> forall(member(Spec, Inputs), 1441 rdf_load_one(Spec, M, Options)) 1442 ; maplist(load_goal(Options, M), Inputs, Goals), 1443 concurrent(Jobs, Goals, []) 1444 ). 1445rdf_load_noagc(One, M, Options) :- 1446 must_be(ground, One), 1447 rdf_load_one(One, M, Options). 1448 1449load_goal(Options, M, Spec, rdf_load_one(Spec, M, Options)). 1450 1451load_jobs(_, Jobs, Options) :- 1452 option(concurrent(Jobs), Options), 1453 !, 1454 must_be(positive_integer, Jobs). 1455load_jobs(Count, Jobs, _) :- 1456 current_prolog_flag(cpu_count, CPUs), 1457 CPUs > 0, 1458 !, 1459 Jobs is max(1, min(CPUs, Count)). 1460load_jobs(_, 1, _). 1461 1462 1463rdf_load_one(Spec, M, Options) :- 1464 source_url(Spec, Protocol, SourceURL), 1465 load_graph(SourceURL, Graph, Options), 1466 setup_call_cleanup( 1467 with_mutex(rdf_load_file, 1468 rdf_start_load(SourceURL, Loading)), 1469 rdf_load_file(Loading, Spec, SourceURL, Protocol, 1470 Graph, M, Options), 1471 rdf_end_load(Loading)).
1488rdf_start_load(SourceURL, queue(Queue)) :- 1489 rdf_loading(SourceURL, Queue, LoadThread), 1490 \+ thread_self(LoadThread), 1491 !, 1492 debug(rdf(load), '~p is being loaded by thread ~w; waiting ...', 1493 [ SourceURL, LoadThread]). 1494rdf_start_load(SourceURL, Ref) :- 1495 thread_self(Me), 1496 message_queue_create(Queue), 1497 assertz(rdf_loading(SourceURL, Queue, Me), Ref). 1498 1499rdf_end_load(queue(_)) :- !. 1500rdf_end_load(Ref) :- 1501 clause(rdf_loading(_, Queue, _), _, Ref), 1502 erase(Ref), 1503 thread_send_message(Queue, done), 1504 message_queue_destroy(Queue). 1505 1506rdf_load_file(queue(Queue), _Spec, _SourceURL, _Protocol, _Graph, _M, _Options) :- 1507 !, 1508 catch(thread_get_message(Queue, _), _, true). 1509rdf_load_file(_Ref, _Spec, SourceURL, Protocol, Graph, M, Options) :- 1510 debug(rdf(load), 'RDF: Loading ~q into ~q', [SourceURL, Graph]), 1511 statistics(cputime, T0), 1512 rdf_open_input(SourceURL, Protocol, Graph, 1513 In, Cleanup, Modified, Format, Options), 1514 supported_format(Format, Cleanup), 1515 return_modified(Modified, Options), 1516 ( Modified == not_modified 1517 -> Action = none 1518 ; Modified = cached(CacheFile) 1519 -> do_unload(Graph), 1520 catch(rdf_load_db_no_admin(CacheFile, cache(Graph), Graphs), _, fail), 1521 check_loaded_cache(Graph, Graphs, Modified), 1522 Action = load 1523 ; option(base_uri(BaseURI), Options, Graph), 1524 ( var(BaseURI) 1525 -> BaseURI = SourceURL 1526 ; true 1527 ), 1528 once(phrase(derived_options(Options, NSList), Extra)), 1529 merge_options([ base_uri(BaseURI), 1530 graph(Graph), 1531 format(Format) 1532 | Extra 1533 ], Options, RDFOptions), 1534 do_unload(Graph), 1535 graph_modified(Modified, ModifiedStamp), 1536 rdf_set_graph_source(Graph, SourceURL, ModifiedStamp), 1537 call_cleanup(rdf_load_stream(Format, In, M:RDFOptions), 1538 Cleanup), 1539 save_cache(Graph, SourceURL, Options), 1540 register_file_prefixes(NSList), 1541 format_action(Format, Action) 1542 ), 1543 rdf_statistics_(triples(Graph, Triples)), 1544 report_loaded(Action, SourceURL, Graph, Triples, T0, Options). 1545 1546supported_format(Format, _Cleanup) :- 1547 rdf_file_type(_, Format), 1548 !. 1549supported_format(Format, Cleanup) :- 1550 call(Cleanup), 1551 existence_error(rdf_format_plugin, Format). 1552 1553format_action(triples, load) :- !. 1554format_action(_, parsed). 1555 1556save_cache(Graph, SourceURL, Options) :- 1557 option(cache(true), Options, true), 1558 rdf_cache_file(SourceURL, write, CacheFile), 1559 !, 1560 catch(save_cache(Graph, CacheFile), E, 1561 print_message(warning, E)). 1562save_cache(_, _, _). 1563 1564derived_options([], _) --> 1565 []. 1566derived_options([H|T], NSList) --> 1567 ( { H == register_namespaces(true) 1568 ; H == (register_namespaces = true) 1569 } 1570 -> [ namespaces(NSList) ] 1571 ; [] 1572 ), 1573 derived_options(T, NSList). 1574 1575graph_modified(last_modified(Stamp), Stamp). 1576graph_modified(unknown, Stamp) :- 1577 get_time(Stamp). 1578 1579return_modified(Modified, Options) :- 1580 option(modified(M0), Options), 1581 !, 1582 M0 = Modified. 1583return_modified(_, _). 1584 1585 1586 /******************************* 1587 * INPUT HANDLING * 1588 *******************************/ 1589 1590/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1591This section deals with pluggable input sources. The task of the input 1592layer is 1593 1594 * Decide on the graph-name 1595 * Decide on the source-location 1596 * Decide whether loading is needed (if-modified) 1597 * Decide on the serialization in the input 1598 1599The protocol must ensure minimal overhead, in particular for network 1600protocols. E.g. for HTTP we want to make a single call on the server and 1601use If-modified-since to verify that we need not reloading this file. 1602- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
Options processed:
graph(Graph)db(Graph)if(Condition)cache(Cache)format(Format)
1620rdf_open_input(SourceURL, Protocol, Graph,
1621 Stream, Cleanup, Modified, Format, Options) :-
1622 option(if(If), Options, changed),
1623 ( If == true
1624 -> true
1625 ; rdf_graph_source_(Graph, SourceURL, HaveModified)
1626 -> true
1627 ; option(cache(true), Options, true),
1628 rdf_cache_file(SourceURL, read, CacheFile)
1629 -> time_file(CacheFile, HaveModified)
1630 ; true
1631 ),
1632 option(format(Format), Options, _),
1633 open_input_if_modified(Protocol, SourceURL, HaveModified,
1634 Stream, Cleanup, Modified0, Format, Options),
1635 ( Modified0 == not_modified
1636 -> ( nonvar(CacheFile)
1637 -> Modified = cached(CacheFile)
1638 ; Modified = not_modified
1639 )
1640 ; Modified = Modified0
1641 ).stream(Stream)http)1652source_url(stream(In), stream(In), SourceURL) :- 1653 !, 1654 ( stream_property(In, file_name(File)) 1655 -> to_url(File, SourceURL) 1656 ; gensym('stream://', SourceURL) 1657 ). 1658source_url(Stream, Class, SourceURL) :- 1659 is_stream(Stream), 1660 !, 1661 source_url(stream(Stream), Class, SourceURL). 1662source_url(Spec, Protocol, SourceURL) :- 1663 compound(Spec), 1664 !, 1665 source_file(Spec, Protocol, SourceURL). 1666source_url(FileURL, Protocol, SourceURL) :- % or return FileURL? 1667 uri_file_name(FileURL, File), 1668 !, 1669 source_file(File, Protocol, SourceURL). 1670source_url(SourceURL0, Protocol, SourceURL) :- 1671 is_url(SourceURL0, Protocol, SourceURL), 1672 !. 1673source_url(File, Protocol, SourceURL) :- 1674 source_file(File, Protocol, SourceURL). 1675 1676source_file(Spec, file(SExt), SourceURL) :- 1677 findall(Ext, valid_extension(Ext), Exts), 1678 absolute_file_name(Spec, File, [access(read), extensions([''|Exts])]), 1679 storage_extension(_Plain, SExt, File), 1680 uri_file_name(SourceURL, File). 1681 1682to_url(URL, URL) :- 1683 uri_is_global(URL), 1684 !. 1685to_url(File, URL) :- 1686 absolute_file_name(File, Path), 1687 uri_file_name(URL, Path). 1688 1689storage_extension(Plain, SExt, File) :- 1690 file_name_extension(Plain, SExt, File), 1691 SExt \== '', 1692 rdf_storage_encoding(SExt, _), 1693 !. 1694storage_extension(File, '', File).
graph(Graph) optiondb(Graph) option (backward compatibility)base_uri(BaseURI) option1706load_graph(Source, Graph, Options) :- 1707 ( option(graph(Graph), Options) 1708 ; option(db(Graph), Options) 1709 ), 1710 !, 1711 load_graph2(Source, Graph, Options). 1712load_graph(Source, Graph, Options) :- 1713 load_graph2(Source, Graph, Options). 1714 1715load_graph2(_, Graph, _) :- 1716 ground(Graph), 1717 !. 1718load_graph2(_Source, Graph, Options) :- 1719 option(base_uri(Graph), Options), 1720 Graph \== [], 1721 ground(Graph), 1722 !. 1723load_graph2(Source, Graph, _) :- 1724 load_graph(Source, Graph). 1725 1726load_graph(SourceURL, BaseURI) :- 1727 file_name_extension(BaseURI, Ext, SourceURL), 1728 rdf_storage_encoding(Ext, _), 1729 !. 1730load_graph(SourceURL, SourceURL). 1731 1732 1733open_input_if_modified(stream(In), SourceURL, _, In, true, 1734 unknown, Format, _) :- 1735 !, 1736 ( var(Format) 1737 -> guess_format(SourceURL, Format) 1738 ; true 1739 ). 1740open_input_if_modified(file(SExt), SourceURL, HaveModified, Stream, Cleanup, 1741 Modified, Format, _) :- 1742 !, 1743 uri_file_name(SourceURL, File), 1744 ( SExt == '' -> Plain = File; file_name_extension(Plain, SExt, File)), 1745 time_file(File, LastModified), 1746 ( nonvar(HaveModified), 1747 HaveModified >= LastModified 1748 -> Modified = not_modified, 1749 Cleanup = true 1750 ; storage_open(SExt, File, Stream, Cleanup), 1751 Modified = last_modified(LastModified), 1752 ( var(Format) 1753 -> guess_format(Plain, Format) 1754 ; true 1755 ) 1756 ). 1757open_input_if_modified(file, SourceURL, HaveModified, Stream, Cleanup, 1758 Modified, Format, Options) :- 1759 !, 1760 open_input_if_modified(file(''), SourceURL, HaveModified, 1761 Stream, Cleanup, 1762 Modified, Format, Options). 1763open_input_if_modified(Protocol, SourceURL, HaveModified, Stream, Cleanup, 1764 Modified, Format, Options) :- 1765 rdf_open_hook(Protocol, SourceURL, HaveModified, Stream, Cleanup, 1766 Modified, Format, Options). 1767 1768guess_format(File, Format) :- 1769 file_name_extension(_, Ext, File), 1770 ( rdf_file_type(Ext, Format) 1771 -> true 1772 ; Format = xml, 1773 print_message(warning, rdf(guess_format(Ext))) 1774 ).
1782storage_open('', File, Stream, close(Stream)) :- 1783 !, 1784 open(File, read, Stream, [type(binary)]). 1785storage_open(Ext, File, Stream, Cleanup) :- 1786 rdf_storage_encoding(Ext, Encoding), 1787 rdf_open_decode(Encoding, File, Stream, Cleanup). 1788 1789valid_extension(Ext) :- 1790 rdf_file_type(Ext, _). 1791valid_extension(Ext) :- 1792 rdf_storage_encoding(Ext, _).
1802is_url(URL, Scheme, FetchURL) :- 1803 atom(URL), 1804 uri_is_global(URL), 1805 uri_normalized(URL, URL1), % case normalization 1806 uri_components(URL1, Components), 1807 uri_data(scheme, Components, Scheme0), 1808 url_protocol(Scheme0), 1809 !, 1810 Scheme = Scheme0, 1811 uri_data(fragment, Components, _, Components1), 1812 uri_components(FetchURL, Components1). 1813 1814url_protocol(file). % built-in
1822rdf_file_type(xml, xml). 1823rdf_file_type(rdf, xml). 1824rdf_file_type(rdfs, xml). 1825rdf_file_type(owl, xml). 1826rdf_file_type(htm, xhtml). 1827rdf_file_type(html, xhtml). 1828rdf_file_type(xhtml, xhtml). 1829rdf_file_type(trp, triples).
1836rdf_storage_encoding('', plain).1845rdf_load_stream(xml, Stream, Options) :- 1846 !, 1847 graph(Options, Graph), 1848 rdf_transaction(load_stream(Stream, Options), 1849 parse(Graph)). 1850rdf_load_stream(xhtml, Stream, M:Options) :- 1851 !, 1852 graph(Options, Graph), 1853 rdf_transaction(load_stream(Stream, M:[embedded(true)|Options]), 1854 parse(Graph)). 1855rdf_load_stream(triples, Stream, Options) :- 1856 !, 1857 graph(Options, Graph), 1858 rdf_load_db_(Stream, Graph, _Graphs). 1859 1860load_stream(Stream, M:Options) :- 1861 process_rdf(Stream, assert_triples, M:Options), 1862 option(graph(Graph), Options), 1863 rdf_graph_clear_modified_(Graph).
1868report_loaded(none, _, _, _, _, _) :- !. 1869report_loaded(Action, Source, DB, Triples, T0, Options) :- 1870 statistics(cputime, T1), 1871 Time is T1 - T0, 1872 ( option(silent(true), Options) 1873 -> Level = silent 1874 ; Level = informational 1875 ), 1876 print_message(Level, 1877 rdf(loaded(Action, Source, DB, Triples, Time))).
1890rdf_unload(Spec) :- 1891 source_url(Spec, _Protocol, SourceURL), 1892 rdf_graph_source_(Graph, SourceURL, _), 1893 !, 1894 rdf_unload_graph(Graph). 1895rdf_unload(Graph) :- 1896 atom(Graph), 1897 rdf_graph(Graph), 1898 !, 1899 warn_deprecated_unload(Graph), 1900 rdf_unload_graph(Graph). 1901rdf_unload(_). 1902 1903:- dynamic 1904 warned/0. 1905 1906warn_deprecated_unload(_) :- 1907 warned, 1908 !. 1909warn_deprecated_unload(Graph) :- 1910 assertz(warned), 1911 print_message(warning, rdf(deprecated(rdf_unload(Graph)))).
1919rdf_unload_graph(Graph) :- 1920 must_be(atom, Graph), 1921 ( rdf_graph(Graph) 1922 -> rdf_transaction(do_unload(Graph), unload(Graph)) 1923 ; true 1924 ). 1925 1926do_unload(Graph) :- 1927 ( rdf_graph_(Graph, Triples), 1928 Triples > 0 1929 -> rdf_retractall(_,_,_,Graph) 1930 ; true 1931 ), 1932 rdf_destroy_graph(Graph). 1933 1934 /******************************* 1935 * GRAPH QUERIES * 1936 *******************************/
1948rdf_graph(Graph) :-
1949 rdf_graph_(Graph, _Triples).
1957rdf_source(Graph, SourceURL) :-
1958 rdf_graph(Graph),
1959 rdf_graph_source_(Graph, SourceURL, _Modified).
1967rdf_source(SourceURL) :-
1968 rdf_source(_Graph, SourceURL).1975rdf_make :- 1976 findall(Source-Graph, modified_graph(Source, Graph), Modified), 1977 forall(member(Source-Graph, Modified), 1978 catch(rdf_load(Source, [graph(Graph), if(changed)]), E, 1979 print_message(error, E))). 1980 1981modified_graph(SourceURL, Graph) :- 1982 rdf_graph(Graph), 1983 rdf_graph_source_(Graph, SourceURL, Modified), 1984 \+ sub_atom(SourceURL, 0, _, _, 'stream://'), 1985 Modified > 0.
modified(false).Additional graph properties can be added by defining rules for the multifile predicate property_of_graph/2. Currently, the following extensions are defined:
library(semweb/rdf_persistency)
true if the graph is persistent.2013rdf_graph_property(Graph, Property) :- 2014 rdf_graph(Graph), 2015 property_of_graph(Property, Graph). 2016 2017:- multifile 2018 property_of_graph/2. 2019 2020property_of_graph(hash(Hash), Graph) :- 2021 rdf_md5(Graph, Hash). 2022property_of_graph(modified(Boolean), Graph) :- 2023 rdf_graph_modified_(Graph, Boolean, _). 2024property_of_graph(source(URL), Graph) :- 2025 rdf_graph_source_(Graph, URL, _). 2026property_of_graph(source_last_modified(Time), Graph) :- 2027 rdf_graph_source_(Graph, _, Time), 2028 Time > 0.0. 2029property_of_graph(triples(Count), Graph) :- 2030 rdf_graph_(Graph, Count).
2039rdf_set_graph(Graph, modified(Modified)) :-
2040 must_be(oneof([false]), Modified),
2041 rdf_graph_clear_modified_(Graph).
2048save_cache(DB, Cache) :-
2049 current_prolog_flag(rdf_triple_format, Version),
2050 setup_call_cleanup(
2051 catch(open(Cache, write, CacheStream, [type(binary)]), _, fail),
2052 rdf_save_db_(CacheStream, DB, Version),
2053 close(CacheStream)).2061assert_triples([], _). 2062assert_triples([rdf(S,P,O)|T], DB) :- 2063 !, 2064 rdf_assert(S, P, O, DB), 2065 assert_triples(T, DB). 2066assert_triples([H|_], _) :- 2067 throw(error(type_error(rdf_triple, H), _)). 2068 2069 2070 /******************************* 2071 * RESET * 2072 *******************************/
2085rdf_reset_db :- 2086 reset_gensym('_:genid'), 2087 rdf_reset_db_. 2088 2089 2090 /******************************* 2091 * SAVE RDF * 2092 *******************************/
rdf_save(Out, []). See rdf_save/2 for details.write_xml_base optiontrue (default false), inline resources when
encountered for the first time. Normally, only bnodes
are handled this way.true (default false), emit subjects sorted on
the full URI. Useful to make file comparison easier.false, do not include the xml:base
declaration that is written normally when using the
base_uri option.false (default true), never use xml attributes to
save plain literal attributes, i.e., always used an XML
element as in <name>Joe</name>.2154:- thread_local 2155 named_anon/2, % +Resource, -Id 2156 inlined/1. % +Resource 2157 2158rdf_save(File) :- 2159 rdf_save2(File, []). 2160 2161rdf_save(Spec, M:Options0) :- 2162 is_list(Options0), 2163 !, 2164 meta_options(save_meta_option, M:Options0, Options), 2165 to_file(Spec, File), 2166 rdf_save2(File, Options). 2167rdf_save(Spec, _:DB) :- 2168 atom(DB), % backward compatibility 2169 !, 2170 to_file(Spec, File), 2171 rdf_save2(File, [graph(DB)]). 2172 2173save_meta_option(convert_typed_literal). 2174 2175to_file(URL, File) :- 2176 atom(URL), 2177 uri_file_name(URL, File), 2178 !. 2179to_file(File, File). 2180 2181rdf_save2(File, Options) :- 2182 option(encoding(Encoding), Options, utf8), 2183 valid_encoding(Encoding), 2184 open_output(File, Encoding, Out, Close), 2185 flag(rdf_db_saved_subjects, OSavedSubjects, 0), 2186 flag(rdf_db_saved_triples, OSavedTriples, 0), 2187 call_cleanup(rdf_do_save(Out, Options), 2188 Reason, 2189 cleanup_save(Reason, 2190 File, 2191 OSavedSubjects, 2192 OSavedTriples, 2193 Close)). 2194 2195open_output(stream(Out), Encoding, Out, 2196 set_stream(Out, encoding(Old))) :- 2197 !, 2198 stream_property(Out, encoding(Old)), 2199 set_stream(Out, encoding(Encoding)). 2200open_output(File, Encoding, Out, 2201 close(Out)) :- 2202 open(File, write, Out, [encoding(Encoding)]). 2203 2204valid_encoding(Enc) :- 2205 ( xml_encoding_name(Enc, _) 2206 -> true 2207 ; throw(error(domain_error(encoding, Enc), _)) 2208 ). 2209 2210 2211cleanup_save(Reason, 2212 File, 2213 OSavedSubjects, 2214 OSavedTriples, 2215 Close) :- 2216 call(Close), 2217 flag(rdf_db_saved_subjects, SavedSubjects, OSavedSubjects), 2218 flag(rdf_db_saved_triples, SavedTriples, OSavedTriples), 2219 retractall(named_anon(_, _)), 2220 retractall(inlined(_)), 2221 ( Reason == exit 2222 -> print_message(informational, 2223 rdf(saved(File, SavedSubjects, SavedTriples))) 2224 ; format(user_error, 'Reason = ~w~n', [Reason]) 2225 ). 2226 2227rdf_do_save(Out, Options0) :- 2228 rdf_save_header(Out, Options0, Options), 2229 graph(Options, DB), 2230 ( option(sorted(true), Options, false) 2231 -> ( var(DB) 2232 -> setof(Subject, rdf_subject(Subject), Subjects) 2233 ; findall(Subject, rdf(Subject, _, _, DB:_), SubjectList), 2234 sort(SubjectList, Subjects) 2235 ), 2236 forall(member(Subject, Subjects), 2237 rdf_save_non_anon_subject(Out, Subject, Options)) 2238 ; forall(rdf_subject_in_graph(Subject, DB), 2239 rdf_save_non_anon_subject(Out, Subject, Options)) 2240 ), 2241 rdf_save_footer(Out), 2242 !. % dubious cut; without the 2243 % cleanup handlers isn't called!?
2254rdf_subject_in_graph(Subject, DB) :- 2255 var(DB), 2256 !, 2257 rdf_subject(Subject). 2258rdf_subject_in_graph(Subject, DB) :- 2259 rdf_statistics(triples(AllTriples)), 2260 rdf_graph_property(DB, triples(DBTriples)), 2261 DBTriples > AllTriples // 10, 2262 !, 2263 rdf_resource(Subject), 2264 ( rdf(Subject, _, _, DB:_) 2265 -> true 2266 ). 2267rdf_subject_in_graph(Subject, DB) :- 2268 findall(Subject, rdf(Subject, _, _, DB:_), SubjectList), 2269 list_to_set(SubjectList, Subjects), 2270 member(Subject, Subjects). 2271 2272 2273graph(Options0, DB) :- 2274 strip_module(Options0, _, Options), 2275 ( memberchk(graph(DB0), Options) 2276 -> DB = DB0 2277 ; memberchk(db(DB0), Options) 2278 -> DB = DB0 2279 ; true % leave unbound 2280 ).
Save an RDF header, with the XML header, DOCTYPE, ENTITY and opening the rdf:RDF element with appropriate namespace declarations. It uses the primitives from section 3.5 to generate the required namespaces and desired short-name. Options is one of:
rdf and rdfs
are added to the provided List. If a namespace is not
declared, the resource is emitted in non-abreviated form.2305rdf_save_header(Out, Options) :- 2306 rdf_save_header(Out, Options, _). 2307 2308rdf_save_header(Out, Options, OptionsOut) :- 2309 is_list(Options), 2310 !, 2311 stream_property(Out, encoding(Enc)), 2312 xml_encoding(Enc, Encoding), 2313 format(Out, '<?xml version=\'1.0\' encoding=\'~w\'?>~n', [Encoding]), 2314 format(Out, '<!DOCTYPE rdf:RDF [', []), 2315 header_namespaces(Options, NSIdList), 2316 nsmap(NSIdList, NsMap), 2317 append(Options, [nsmap(NsMap)], OptionsOut), 2318 forall(member(Id=URI, NsMap), 2319 ( xml_quote_attribute(URI, NSText0, Enc), 2320 xml_escape_parameter_entity(NSText0, NSText), 2321 format(Out, '~N <!ENTITY ~w \'~w\'>', [Id, NSText]) 2322 )), 2323 format(Out, '~N]>~n~n', []), 2324 format(Out, '<rdf:RDF', []), 2325 ( member(Id, NSIdList), 2326 format(Out, '~N xmlns:~w="&~w;"~n', [Id, Id]), 2327 fail 2328 ; true 2329 ), 2330 ( option(base_uri(Base), Options), 2331 option(write_xml_base(true), Options, true) 2332 -> xml_quote_attribute(Base, BaseText, Enc), 2333 format(Out, '~N xml:base="~w"~n', [BaseText]) 2334 ; true 2335 ), 2336 ( memberchk(document_language(Lang), Options) 2337 -> format(Out, '~N xml:lang="~w"', [Lang]) 2338 ; true 2339 ), 2340 format(Out, '>~n', []). 2341rdf_save_header(Out, FileRef, OptionsOut) :- % compatibility 2342 atom(FileRef), 2343 rdf_save_header(Out, [graph(FileRef)], OptionsOut). 2344 2345xml_encoding(Enc, Encoding) :- 2346 ( xml_encoding_name(Enc, Encoding) 2347 -> true 2348 ; throw(error(domain_error(rdf_encoding, Enc), _)) 2349 ). 2350 2351xml_encoding_name(ascii, 'US-ASCII'). 2352xml_encoding_name(iso_latin_1, 'ISO-8859-1'). 2353xml_encoding_name(utf8, 'UTF-8').
2360nsmap([], []). 2361nsmap([Id|T0], [Id=URI|T]) :- 2362 ns(Id, URI), 2363 nsmap(T0, T).
2369xml_escape_parameter_entity(In, Out) :- 2370 sub_atom(In, _, _, _, '%'), 2371 !, 2372 atom_codes(In, Codes), 2373 phrase(escape_parent(Codes), OutCodes), 2374 atom_codes(Out, OutCodes). 2375xml_escape_parameter_entity(In, In). 2376 2377escape_parent([]) --> []. 2378escape_parent([H|T]) --> 2379 ( { H == 37 } 2380 -> "%" 2381 ; [H] 2382 ), 2383 escape_parent(T).
2390header_namespaces(Options, List) :- 2391 memberchk(namespaces(NSL0), Options), 2392 !, 2393 sort([rdf,rdfs|NSL0], List). 2394header_namespaces(Options, List) :- 2395 graph(Options, DB), 2396 used_namespace_entities(List, DB).
call(Filter, Where, Prefix, URI)
The Where argument gives the location of the prefix ans is
one of subject, predicate, object or type. The
Prefix argument is the potentionally new prefix and URI is
the full URI that is being processed.
call(Goal,S,P,O,Graph)
2434:- thread_local 2435 graph_prefix/3. 2436:- meta_predicate 2437 rdf_graph_prefixes(, , ). 2438 2439rdf_graph_prefixes(Graph, List) :- 2440 rdf_graph_prefixes(Graph, List, []). 2441 2442rdf_graph_prefixes(Graph, List, M:QOptions) :- 2443 is_list(QOptions), 2444 !, 2445 meta_options(is_meta, M:QOptions, Options), 2446 option(filter(Filter), Options, true), 2447 option(expand(Expand), Options, rdf_db), 2448 option(min_count(MinCount), Options, 1), 2449 option(get_prefix(GetPrefix), Options, iri_xml_namespace), 2450 call_cleanup(prefixes(Expand, Graph, Prefixes, Filter, MinCount, GetPrefix), 2451 retractall(graph_prefix(_,_,_))), 2452 sort(Prefixes, List). 2453rdf_graph_prefixes(Graph, List, M:Filter) :- 2454 rdf_graph_prefixes(Graph, List, M:[filter(Filter)]). 2455 2456is_meta(filter). 2457is_meta(expand). 2458is_meta(get_prefix). 2459 2460 2461prefixes(Expand, Graph, Prefixes, Filter, MinCount, GetPrefix) :- 2462 ( call(Expand, S, P, O, Graph), 2463 add_ns(subject, GetPrefix, Filter, S, MinCount, s(S)), 2464 add_ns(predicate, GetPrefix, Filter, P, MinCount, sp(S,P)), 2465 add_ns_obj(GetPrefix, Filter, O, MinCount, spo(S,P,O)), 2466 fail 2467 ; true 2468 ), 2469 findall(Prefix, graph_prefix(Prefix, MinCount, _), Prefixes). 2470 2471add_ns(Where, GetPrefix, Filter, S, MinCount, Context) :- 2472 \+ rdf_is_bnode(S), 2473 call(GetPrefix, S, Full), 2474 Full \== '', 2475 !, 2476 ( graph_prefix(Full, MinCount, _) 2477 -> true 2478 ; Filter == true 2479 -> add_ns(Full, Context) 2480 ; call(Filter, Where, Full, S) 2481 -> add_ns(Full, Context) 2482 ; true 2483 ). 2484add_ns(_, _, _, _, _, _). 2485 2486add_ns(Full, Context) :- 2487 graph_prefix(Full, _, Contexts), 2488 memberchk(Context, Contexts), 2489 !. 2490add_ns(Full, Context) :- 2491 retract(graph_prefix(Full, C0, Contexts)), 2492 !, 2493 C1 is C0+1, 2494 asserta(graph_prefix(Full, C1, [Context|Contexts])). 2495add_ns(Full, _) :- 2496 ns(_, Full), 2497 !, 2498 asserta(graph_prefix(Full, _, _)). 2499add_ns(Full, Context) :- 2500 asserta(graph_prefix(Full, 1, [Context])). 2501 2502 2503add_ns_obj(GetPrefix, Filter, O, MinCount, Context) :- 2504 atom(O), 2505 !, 2506 add_ns(object, GetPrefix, Filter, O, MinCount, Context). 2507add_ns_obj(GetPrefix, Filter, literal(type(Type, _)), MinCount, _) :- 2508 atom(Type), 2509 !, 2510 add_ns(type, GetPrefix, Filter, Type, MinCount, t(Type)). 2511add_ns_obj(_, _, _, _, _).
2521used_namespace_entities(List, Graph) :- 2522 decl_used_predicate_ns(Graph), 2523 used_namespaces(List, Graph). 2524 2525used_namespaces(List, DB) :- 2526 rdf_graph_prefixes(DB, FullList), 2527 ns_abbreviations(FullList, List0), 2528 sort([rdf|List0], List). 2529 2530ns_abbreviations([], []). 2531ns_abbreviations([H0|T0], [H|T]) :- 2532 ns(H, H0), 2533 !, 2534 ns_abbreviations(T0, T). 2535ns_abbreviations([_|T0], T) :- 2536 ns_abbreviations(T0, T). 2537 2538 2539/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2540For every URL used as a predicate we *MUST* define a namespace as we 2541cannot use names holding /, :, etc. as XML identifiers. 2542- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ 2543 2544:- thread_local 2545 predicate_ns/2. 2546 2547decl_used_predicate_ns(DB) :- 2548 retractall(predicate_ns(_,_)), 2549 ( rdf_current_predicate(P, DB), 2550 decl_predicate_ns(P), 2551 fail 2552 ; true 2553 ). 2554 2555decl_predicate_ns(Pred) :- 2556 predicate_ns(Pred, _), 2557 !. 2558decl_predicate_ns(Pred) :- 2559 rdf_global_id(NS:Local, Pred), 2560 xml_name(Local), 2561 !, 2562 assert(predicate_ns(Pred, NS)). 2563decl_predicate_ns(Pred) :- 2564 atom_codes(Pred, Codes), 2565 append(NSCodes, LocalCodes, Codes), 2566 xml_codes(LocalCodes), 2567 !, 2568 ( NSCodes \== [] 2569 -> atom_codes(NS, NSCodes), 2570 ( ns(Id, NS) 2571 -> assert(predicate_ns(Pred, Id)) 2572 ; between(1, infinite, N), 2573 atom_concat(ns, N, Id), 2574 \+ ns(Id, _) 2575 -> rdf_register_ns(Id, NS), 2576 print_message(informational, 2577 rdf(using_namespace(Id, NS))) 2578 ), 2579 assert(predicate_ns(Pred, Id)) 2580 ; assert(predicate_ns(Pred, -)) % no namespace used 2581 ). 2582 2583xml_codes([]). 2584xml_codes([H|T]) :- 2585 xml_code(H), 2586 xml_codes(T). 2587 2588xml_code(X) :- 2589 code_type(X, csym), 2590 !. 2591xml_code(0'-). % Match 0'-
2600rdf_save_footer(Out) :-
2601 retractall(named_anon(_, _)),
2602 retractall(inlined(_)),
2603 format(Out, '</rdf:RDF>~n', []).anon(false)
is present in the Options list.2610rdf_save_non_anon_subject(_Out, Subject, Options) :- 2611 rdf_is_bnode(Subject), 2612 ( memberchk(anon(false), Options) 2613 ; graph(Options, DB), 2614 rdf_db(_, _, Subject, DB) 2615 ), 2616 !. 2617rdf_save_non_anon_subject(Out, Subject, Options) :- 2618 rdf_save_subject(Out, Subject, Options), 2619 flag(rdf_db_saved_subjects, X, X+1).
2634rdf_save_subject(Out, Subject, Options) :- 2635 is_list(Options), 2636 !, 2637 option(base_uri(BaseURI), Options, '-'), 2638 ( rdf_save_subject(Out, Subject, BaseURI, 0, Options) 2639 -> format(Out, '~n', []) 2640 ; throw(error(rdf_save_failed(Subject), 'Internal error')) 2641 ). 2642rdf_save_subject(Out, Subject, DB) :- 2643 ( var(DB) 2644 -> rdf_save_subject(Out, Subject, []) 2645 ; rdf_save_subject(Out, Subject, [graph(DB)]) 2646 ).
2656rdf_save_subject(_, Subject, _, _, _) :- 2657 inlined(Subject), 2658 !. 2659rdf_save_subject(Out, Subject, BaseURI, Indent, Options) :- 2660 do_save_subject(Out, Subject, BaseURI, Indent, Options). 2661 2662do_save_subject(Out, Subject, BaseURI, Indent, Options) :- 2663 graph(Options, DB), 2664 findall(Pred=Object, rdf_db(Subject, Pred, Object, DB), Atts0), 2665 sort(Atts0, Atts), % remove duplicates 2666 length(Atts, L), 2667 ( length(Atts0, L0), 2668 Del is L0-L, 2669 Del > 0 2670 -> print_message(informational, 2671 rdf(save_removed_duplicates(Del, Subject))) 2672 ; true 2673 ), 2674 rdf_save_subject(Out, Subject, BaseURI, Atts, Indent, Options), 2675 flag(rdf_db_saved_triples, X, X+L). 2676 2677rdf_db(Subject, Pred, Object, DB) :- 2678 var(DB), 2679 !, 2680 rdf(Subject, Pred, Object). 2681rdf_db(Subject, Pred, Object, DB) :- 2682 rdf(Subject, Pred, Object, DB:_).
2689rdf_save_subject(Out, Subject, BaseURI, Atts, Indent, Options) :- 2690 rdf_equal(rdf:type, RdfType), 2691 select(RdfType=Type, Atts, Atts1), 2692 \+ rdf_is_bnode(Type), 2693 rdf_id(Type, BaseURI, TypeId), 2694 xml_is_name(TypeId), 2695 !, 2696 format(Out, '~*|<', [Indent]), 2697 rdf_write_id(Out, TypeId), 2698 save_about(Out, BaseURI, Subject), 2699 save_attributes(Atts1, BaseURI, Out, TypeId, Indent, Options). 2700rdf_save_subject(Out, Subject, BaseURI, Atts, Indent, Options) :- 2701 format(Out, '~*|<rdf:Description', [Indent]), 2702 save_about(Out, BaseURI, Subject), 2703 save_attributes(Atts, BaseURI, Out, rdf:'Description', Indent, Options). 2704 2705xml_is_name(_NS:Atom) :- 2706 !, 2707 xml_name(Atom). 2708xml_is_name(Atom) :- 2709 xml_name(Atom).
2716save_about(Out, _, Subject) :- 2717 rdf_is_bnode(Subject), 2718 !, 2719 ( named_anon(Subject, NodeID) 2720 -> format(Out, ' rdf:nodeID="~w"', [NodeID]) 2721 ; true 2722 ). 2723save_about(Out, BaseURI, Subject) :- 2724 stream_property(Out, encoding(Encoding)), 2725 rdf_value(Subject, BaseURI, QSubject, Encoding), 2726 format(Out, ' rdf:about="~w"', [QSubject]).
2734save_attributes(Atts, BaseURI, Out, Element, Indent, Options) :-
2735 split_attributes(Atts, InTag, InBody, Options),
2736 SubIndent is Indent + 2,
2737 save_attributes2(InTag, BaseURI, tag, Out, SubIndent, Options),
2738 ( InBody == []
2739 -> format(Out, '/>~n', [])
2740 ; format(Out, '>~n', []),
2741 save_attributes2(InBody, BaseURI, body, Out, SubIndent, Options),
2742 format(Out, '~N~*|</', [Indent]),
2743 rdf_write_id(Out, Element),
2744 format(Out, '>~n', [])
2745 ).2753split_attributes(Atts, [], Atts, Options) :- 2754 option(xml_attributes(false), Options), 2755 !. 2756split_attributes(Atts, HeadAttr, BodyAttr, _) :- 2757 duplicate_attributes(Atts, Dupls, Singles), 2758 simple_literal_attributes(Singles, HeadAttr, Rest), 2759 append(Dupls, Rest, BodyAttr).
2766duplicate_attributes([], [], []). 2767duplicate_attributes([H|T], Dupls, Singles) :- 2768 H = (Name=_), 2769 named_attributes(Name, T, D, R), 2770 D \== [], 2771 append([H|D], Dupls2, Dupls), 2772 !, 2773 duplicate_attributes(R, Dupls2, Singles). 2774duplicate_attributes([H|T], Dupls2, [H|Singles]) :- 2775 duplicate_attributes(T, Dupls2, Singles). 2776 2777named_attributes(_, [], [], []) :- !. 2778named_attributes(Name, [H|T], D, R) :- 2779 ( H = (Name=_) 2780 -> D = [H|DT], 2781 named_attributes(Name, T, DT, R) 2782 ; R = [H|RT], 2783 named_attributes(Name, T, D, RT) 2784 ).
2791simple_literal_attributes([], [], []). 2792simple_literal_attributes([H|TA], [H|TI], B) :- 2793 in_tag_attribute(H), 2794 !, 2795 simple_literal_attributes(TA, TI, B). 2796simple_literal_attributes([H|TA], I, [H|TB]) :- 2797 simple_literal_attributes(TA, I, TB). 2798 2799in_tag_attribute(_=literal(Text)) :- 2800 atom(Text), % may not have lang qualifier 2801 atom_length(Text, Len), 2802 Len < 60.
2808save_attributes2([], _, _, _, _, _). 2809save_attributes2([H|T], BaseURI, Where, Out, Indent, Options) :- 2810 save_attribute(Where, H, BaseURI, Out, Indent, Options), 2811 save_attributes2(T, BaseURI, Where, Out, Indent, Options). 2812 2813save_attribute(tag, Name=literal(Value), BaseURI, Out, Indent, _DB) :- 2814 AttIndent is Indent + 2, 2815 rdf_id(Name, BaseURI, NameText), 2816 stream_property(Out, encoding(Encoding)), 2817 xml_quote_attribute(Value, QVal, Encoding), 2818 format(Out, '~N~*|', [AttIndent]), 2819 rdf_write_id(Out, NameText), 2820 format(Out, '="~w"', [QVal]). 2821save_attribute(body, Name=literal(Literal0), BaseURI, Out, Indent, Options) :- 2822 !, 2823 rdf_id(Name, BaseURI, NameText), 2824 ( memberchk(convert_typed_literal(Converter), Options), 2825 call(Converter, Type, Content, Literal0) 2826 -> Literal = type(Type, Content) 2827 ; Literal = Literal0 2828 ), 2829 save_body_literal(Literal, NameText, BaseURI, Out, Indent, Options). 2830save_attribute(body, Name=Value, BaseURI, Out, Indent, Options) :- 2831 rdf_is_bnode(Value), 2832 !, 2833 rdf_id(Name, BaseURI, NameText), 2834 format(Out, '~N~*|<', [Indent]), 2835 rdf_write_id(Out, NameText), 2836 ( named_anon(Value, NodeID) 2837 -> format(Out, ' rdf:nodeID="~w"/>', [NodeID]) 2838 ; ( rdf(S1, Name, Value), 2839 rdf(S2, P2, Value), 2840 (S1 \== S2 ; Name \== P2) 2841 -> predicate_property(named_anon(_,_), number_of_clauses(N)), 2842 atom_concat('bn', N, NodeID), 2843 assertz(named_anon(Value, NodeID)) 2844 ; true 2845 ), 2846 SubIndent is Indent + 2, 2847 ( rdf_collection(Value) 2848 -> save_about(Out, BaseURI, Value), 2849 format(Out, ' rdf:parseType="Collection">~n', []), 2850 rdf_save_list(Out, Value, BaseURI, SubIndent, Options) 2851 ; format(Out, '>~n', []), 2852 rdf_save_subject(Out, Value, BaseURI, SubIndent, Options) 2853 ), 2854 format(Out, '~N~*|</', [Indent]), 2855 rdf_write_id(Out, NameText), 2856 format(Out, '>~n', []) 2857 ). 2858save_attribute(body, Name=Value, BaseURI, Out, Indent, Options) :- 2859 option(inline(true), Options), 2860 has_attributes(Value, Options), 2861 \+ inlined(Value), 2862 !, 2863 assertz(inlined(Value)), 2864 rdf_id(Name, BaseURI, NameText), 2865 format(Out, '~N~*|<', [Indent]), 2866 rdf_write_id(Out, NameText), 2867 SubIndent is Indent + 2, 2868 ( rdf_collection(Value) 2869 -> save_about(Out, BaseURI, Value), 2870 format(Out, ' rdf:parseType="Collection">~n', []), 2871 rdf_save_list(Out, Value, BaseURI, SubIndent, Options) 2872 ; format(Out, '>~n', []), 2873 do_save_subject(Out, Value, BaseURI, SubIndent, Options) 2874 ), 2875 format(Out, '~N~*|</', [Indent]), 2876 rdf_write_id(Out, NameText), 2877 format(Out, '>~n', []). 2878save_attribute(body, Name=Value, BaseURI, Out, Indent, _DB) :- 2879 stream_property(Out, encoding(Encoding)), 2880 rdf_value(Value, BaseURI, QVal, Encoding), 2881 rdf_id(Name, BaseURI, NameText), 2882 format(Out, '~N~*|<', [Indent]), 2883 rdf_write_id(Out, NameText), 2884 format(Out, ' rdf:resource="~w"/>', [QVal]). 2885 2886has_attributes(URI, Options) :- 2887 graph(Options, DB), 2888 rdf_db(URI, _, _, DB), 2889 !.
2894save_body_literal(lang(Lang, Value), 2895 NameText, BaseURI, Out, Indent, Options) :- 2896 !, 2897 format(Out, '~N~*|<', [Indent]), 2898 rdf_write_id(Out, NameText), 2899 ( memberchk(document_language(Lang), Options) 2900 -> write(Out, '>') 2901 ; rdf_id(Lang, BaseURI, LangText), 2902 format(Out, ' xml:lang="~w">', [LangText]) 2903 ), 2904 save_attribute_value(Value, Out, Indent), 2905 write(Out, '</'), rdf_write_id(Out, NameText), write(Out, '>'). 2906save_body_literal(type(Type, DOM), 2907 NameText, _BaseURI, Out, Indent, Options) :- 2908 rdf_equal(Type, rdf:'XMLLiteral'), 2909 !, 2910 ( atom(DOM) 2911 -> format(Out, '~N~*|<', [Indent]), 2912 rdf_write_id(Out, NameText), 2913 format(Out, ' rdf:parseType="Literal">~w</', [DOM]), 2914 rdf_write_id(Out, NameText), write(Out, '>') 2915 ; save_xml_literal(DOM, NameText, Out, Indent, Options) 2916 ). 2917save_body_literal(type(Type, Value), 2918 NameText, BaseURI, Out, Indent, _) :- 2919 !, 2920 format(Out, '~N~*|<', [Indent]), 2921 rdf_write_id(Out, NameText), 2922 stream_property(Out, encoding(Encoding)), 2923 rdf_value(Type, BaseURI, QVal, Encoding), 2924 format(Out, ' rdf:datatype="~w">', [QVal]), 2925 save_attribute_value(Value, Out, Indent), 2926 write(Out, '</'), rdf_write_id(Out, NameText), write(Out, '>'). 2927save_body_literal(Literal, 2928 NameText, _, Out, Indent, _) :- 2929 atomic(Literal), 2930 !, 2931 format(Out, '~N~*|<', [Indent]), 2932 rdf_write_id(Out, NameText), 2933 write(Out, '>'), 2934 save_attribute_value(Literal, Out, Indent), 2935 write(Out, '</'), rdf_write_id(Out, NameText), write(Out, '>'). 2936save_body_literal(DOM, 2937 NameText, BaseURI, Out, Indent, Options) :- 2938 rdf_equal(Type, rdf:'XMLLiteral'), 2939 save_body_literal(type(Type, DOM), 2940 NameText, BaseURI, Out, Indent, Options). 2941 2942save_attribute_value(Value, Out, _) :- % strings 2943 atom(Value), 2944 !, 2945 stream_property(Out, encoding(Encoding)), 2946 xml_quote_cdata(Value, QVal, Encoding), 2947 write(Out, QVal). 2948save_attribute_value(Value, Out, _) :- % numbers 2949 number(Value), 2950 !, 2951 writeq(Out, Value). % quoted: preserve floats 2952save_attribute_value(Value, _Out, _) :- 2953 throw(error(save_attribute_value(Value), _)).
<prop parseType="literal"
but not the terminating >. We need to establish the
namespaces used in the DOM. The namespaces in the rdf document
are in the nsmap-option of Options.
2967save_xml_literal(DOM, Attr, Out, Indent, Options) :- 2968 xml_is_dom(DOM), 2969 !, 2970 memberchk(nsmap(NsMap), Options), 2971 id_to_atom(Attr, Atom), 2972 xml_write(Out, 2973 element(Atom, ['rdf:parseType'='Literal'], DOM), 2974 [ header(false), 2975 indent(Indent), 2976 nsmap(NsMap) 2977 ]). 2978save_xml_literal(NoDOM, _, _, _, _) :- 2979 must_be(xml_dom, NoDOM). 2980 2981id_to_atom(NS:Local, Atom) :- 2982 !, 2983 atomic_list_concat([NS,Local], :, Atom). 2984id_to_atom(ID, ID).
2994:- rdf_meta 2995 rdf_collection(r), 2996 collection_p(r,r). 2997 2998rdf_collection(rdf:nil) :- !. 2999rdf_collection(Cell) :- 3000 rdf_is_bnode(Cell), 3001 findall(F, rdf(Cell, rdf:first, F), [_]), 3002 findall(F, rdf(Cell, rdf:rest, F), [Rest]), 3003 forall(rdf(Cell, P, V), 3004 collection_p(P, V)), 3005 rdf_collection(Rest). 3006 3007collection_p(rdf:first, V) :- atom(V). 3008collection_p(rdf:rest, _). 3009collection_p(rdf:type, rdf:'List').
3014rdf_save_list(_, List, _, _, _) :- 3015 rdf_equal(List, rdf:nil), 3016 !. 3017rdf_save_list(Out, List, BaseURI, Indent, Options) :- 3018 rdf_has(List, rdf:first, First), 3019 ( rdf_is_bnode(First) 3020 -> nl(Out), 3021 rdf_save_subject(Out, First, BaseURI, Indent, Options) 3022 ; stream_property(Out, encoding(Encoding)), 3023 rdf_value(First, BaseURI, QVal, Encoding), 3024 format(Out, '~N~*|<rdf:Description rdf:about="~w"/>', 3025 [Indent, QVal]) 3026 ), 3027 flag(rdf_db_saved_triples, X, X+3), 3028 ( rdf_has(List, rdf:rest, List2), 3029 \+ rdf_equal(List2, rdf:nil) 3030 -> rdf_save_list(Out, List2, BaseURI, Indent, Options) 3031 ; true 3032 ).
3040rdf_id(Id, BaseURI, Local) :- 3041 assertion(atom(BaseURI)), 3042 atom_concat(BaseURI, Local, Id), 3043 sub_atom(Local, 0, 1, _, #), 3044 !. 3045rdf_id(Id, _, NS:Local) :- 3046 iri_xml_namespace(Id, Full, Local), 3047 ns(NS, Full), 3048 !. 3049rdf_id(Id, _, NS:Local) :- 3050 ns(NS, Full), 3051 Full \== '', 3052 atom_concat(Full, Local, Id), 3053 !. 3054rdf_id(Id, _, Id).
3062rdf_write_id(Out, NS:Local) :- 3063 !, 3064 format(Out, '~w:~w', [NS, Local]). 3065rdf_write_id(Out, Atom) :- 3066 write(Out, Atom).
3075rdf_value(Base, Base, '', _) :- !. 3076rdf_value(V, Base, Text, Encoding) :- 3077 atom_concat(Base, Local, V), 3078 sub_atom(Local, 0, _, _, #), 3079 !, 3080 xml_quote_attribute(Local, Text, Encoding). 3081rdf_value(V, _, Text, Encoding) :- 3082 ns(NS, Full), 3083 atom_concat(Full, Local, V), 3084 xml_is_name(Local), 3085 !, 3086 xml_quote_attribute(Local, QLocal, Encoding), 3087 atomic_list_concat(['&', NS, (';'), QLocal], Text). 3088rdf_value(V, _, Q, Encoding) :- 3089 xml_quote_attribute(V, Q, Encoding). 3090 3091 3092 /******************************* 3093 * MATCH AND COMPARE * 3094 *******************************/
icase, substring, word, prefix or like. For backward
compatibility, exact is a synonym for icase.3117 /******************************* 3118 * DEPRECATED MATERIAL * 3119 *******************************/
library(sgml).
3129rdf_split_url(Prefix, Local, URL) :- 3130 atomic(URL), 3131 !, 3132 iri_xml_namespace(URL, Prefix, Local). 3133rdf_split_url(Prefix, Local, URL) :- 3134 atom_concat(Prefix, Local, URL).
3142rdf_url_namespace(URL, Prefix) :- 3143 iri_xml_namespace(URL, Prefix). 3144 3145 3146 /******************************* 3147 * LITERALS * 3148 *******************************/
rdf_litindex.pl.not(Key). If not-terms are provided, there
must be at least one positive keywords. The negations are tested
after establishing the positive matches.key(+Key)
Succeeds if Key is a key in the map and unify Answer with the
number of values associated with the key. This provides a fast
test of existence without fetching the possibly large
associated value set as with rdf_find_literal_map/3.prefix(+Prefix)
Unify Answer with an ordered set of all keys that have the
given prefix. See section 3.1 for details on prefix matching.
Prefix must be an atom. This call is intended for
auto-completion in user interfaces.ge(+Min)
Unify Answer with all keys that are larger or equal to the
integer Min.le(+Max)
Unify Answer with all keys that are smaller or equal to the integer
Max.between(+Min, +Max) Unify
Answer with all keys between Min and Max (including).3236 /******************************* 3237 * MISC * 3238 *******************************/
Major*10000 + Minor*100 + Patch.
s,
p, sp, o, po, spo, g, sg or pg. Parameter
is one of:
permission_error exception.When inside a transaction, Generation is unified to a term TransactionStartGen + InsideTransactionGen. E.g., 4+3 means that the transaction was started at generation 4 of the global database and we have created 3 new generations inside the transaction. Note that this choice of representation allows for comparing generations using Prolog arithmetic. Comparing a generation in one transaction with a generation in another transaction is meaningless.
3335 /******************************* 3336 * MESSAGES * 3337 *******************************/ 3338 3339:- multifile 3340 prolog:message//1. 3341 3342prologmessage(rdf(Term)) --> 3343 message(Term). 3344 3345message(loaded(How, What, BaseURI, Triples, Time)) --> 3346 how(How), 3347 source(What), 3348 into(What, BaseURI), 3349 in_time(Triples, Time). 3350message(save_removed_duplicates(N, Subject)) --> 3351 [ 'Removed ~d duplicate triples about "~p"'-[N,Subject] ]. 3352message(saved(File, SavedSubjects, SavedTriples)) --> 3353 [ 'Saved ~D triples about ~D subjects into ~p'- 3354 [SavedTriples, SavedSubjects, File] 3355 ]. 3356message(using_namespace(Id, NS)) --> 3357 [ 'Using namespace id ~w for ~w'-[Id, NS] ]. 3358message(inconsistent_cache(DB, Graphs)) --> 3359 [ 'RDF cache file for ~w contains the following graphs'-[DB], nl, 3360 '~t~8|~p'-[Graphs] 3361 ]. 3362message(guess_format(Ext)) --> 3363 [ 'Unknown file-extension: ~w. Assuming RDF/XML'-[Ext] ]. 3364message(meta(not_expanded(G))) --> 3365 [ 'rdf_meta/1: ~p is not expanded'-[G] ]. 3366message(deprecated(rdf_unload(Graph))) --> 3367 [ 'rdf_unload/1: Use ~q'-[rdf_unload_graph(Graph)] ]. 3368 3369 3370how(load) --> [ 'Loaded' ]. 3371how(parsed) --> [ 'Parsed' ]. 3372 3373source(SourceURL) --> 3374 { uri_file_name(SourceURL, File), 3375 !, 3376 file_base_name(File, Base) % TBD: relative file? 3377 }, 3378 [ ' "~w"'-[Base] ]. 3379source(SourceURL) --> 3380 [ ' "~w"'-[SourceURL] ]. 3381 3382into(_, _) --> []. % TBD 3383 3384in_time(Triples, ParseTime) --> 3385 [ ' in ~2f sec; ~D triples'-[ParseTime, Triples] 3386 ]
Core RDF database
The file
library(semweb/rdf_db)provides the core of the SWI-Prolog RDF store.library(semweb/rdf11), which provides a much more intuitive API to the RDF store, notably for handling literals. Thelibrary(semweb/rdf11)runs currently on top of this library and both can run side-by-side in the same application. Terms retrieved from the database however have a different shape and can not be exchanged without precautions. */