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) 2003-2023, University of Amsterdam 7 VU University Amsterdam 8 CWI, Amsterdam 9 SWI-Prolog Solutions b.v. 10 All rights reserved. 11 12 Redistribution and use in source and binary forms, with or without 13 modification, are permitted provided that the following conditions 14 are met: 15 16 1. Redistributions of source code must retain the above copyright 17 notice, this list of conditions and the following disclaimer. 18 19 2. Redistributions in binary form must reproduce the above copyright 20 notice, this list of conditions and the following disclaimer in 21 the documentation and/or other materials provided with the 22 distribution. 23 24 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 25 "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 26 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 27 FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 28 COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 29 INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 30 BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 31 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 32 CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 34 ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35 POSSIBILITY OF SUCH DAMAGE. 36*/ 37 38:- module(rdf_db, 39 [ rdf_version/1, % -Version 40 41 rdf/3, % ?Subject, ?Predicate, ?Object 42 rdf/4, % ?Subject, ?Predicate, ?Object, ?DB 43 rdf_has/3, % ?Subject, +Pred, ?Obj 44 rdf_has/4, % ?Subject, +Pred, ?Obj, -RealPred 45 rdf_reachable/3, % ?Subject, +Pred, ?Object 46 rdf_reachable/5, % ?Subject, +Pred, ?Object, +MaxD, ?D 47 rdf_resource/1, % ?Resource 48 rdf_subject/1, % ?Subject 49 50 rdf_member_property/2, % ?Property, ?Index 51 52 rdf_assert/3, % +Subject, +Predicate, +Object 53 rdf_assert/4, % +Subject, +Predicate, +Object, +DB 54 rdf_retractall/3, % ?Subject, ?Predicate, ?Object 55 rdf_retractall/4, % ?Subject, ?Predicate, ?Object, +DB 56 rdf_update/4, % +Subject, +Predicate, +Object, +Act 57 rdf_update/5, % +Subject, +Predicate, +Object, +Src, +Act 58 rdf_set_predicate/2, % +Predicate, +Property 59 rdf_predicate_property/2, % +Predicate, ?Property 60 rdf_current_predicate/1, % -Predicate 61 rdf_current_literal/1, % -Literal 62 rdf_transaction/1, % :Goal 63 rdf_transaction/2, % :Goal, +Id 64 rdf_transaction/3, % :Goal, +Id, +Options 65 rdf_active_transaction/1, % ?Id 66 67 rdf_monitor/2, % :Goal, +Options 68 69 rdf_save_db/1, % +File 70 rdf_save_db/2, % +File, +DB 71 rdf_load_db/1, % +File 72 rdf_reset_db/0, 73 74 rdf_node/1, % -Id 75 rdf_bnode/1, % -Id 76 rdf_is_bnode/1, % +Id 77 78 rdf_is_resource/1, % +Term 79 rdf_is_literal/1, % +Term 80 rdf_literal_value/2, % +Term, -Value 81 82 rdf_load/1, % +File 83 rdf_load/2, % +File, +Options 84 rdf_save/1, % +File 85 rdf_save/2, % +File, +Options 86 rdf_unload/1, % +File 87 rdf_unload_graph/1, % +Graph 88 89 rdf_md5/2, % +DB, -MD5 90 rdf_atom_md5/3, % +Text, +Times, -MD5 91 92 rdf_create_graph/1, % ?Graph 93 rdf_graph_property/2, % ?Graph, ?Property 94 rdf_set_graph/2, % +Graph, +Property 95 rdf_graph/1, % ?Graph 96 rdf_source/1, % ?File 97 rdf_source/2, % ?DB, ?SourceURL 98 rdf_make/0, % Reload modified databases 99 rdf_gc/0, % Garbage collection 100 101 rdf_source_location/2, % +Subject, -Source 102 rdf_statistics/1, % -Key 103 rdf_set/1, % +Term 104 rdf_generation/1, % -Generation 105 rdf_snapshot/1, % -Snapshot 106 rdf_delete_snapshot/1, % +Snapshot 107 rdf_current_snapshot/1, % +Snapshot 108 rdf_estimate_complexity/4, % +S,+P,+O,-Count 109 110 rdf_save_subject/3, % +Stream, +Subject, +DB 111 rdf_save_header/2, % +Out, +Options 112 rdf_save_footer/1, % +Out 113 114 rdf_equal/2, % ?Resource, ?Resource 115 lang_equal/2, % +Lang1, +Lang2 116 lang_matches/2, % +Lang, +Pattern 117 118 rdf_prefix/2, % :Alias, +URI 119 rdf_current_prefix/2, % :Alias, ?URI 120 rdf_register_prefix/2, % +Alias, +URI 121 rdf_register_prefix/3, % +Alias, +URI, +Options 122 rdf_unregister_prefix/1, % +Alias 123 rdf_current_ns/2, % :Alias, ?URI 124 rdf_register_ns/2, % +Alias, +URI 125 rdf_register_ns/3, % +Alias, +URI, +Options 126 rdf_global_id/2, % ?NS:Name, :Global 127 rdf_global_object/2, % +Object, :NSExpandedObject 128 rdf_global_term/2, % +Term, :WithExpandedNS 129 130 rdf_compare/3, % -Dif, +Object1, +Object2 131 rdf_match_label/3, % +How, +String, +Label 132 rdf_split_url/3, % ?Base, ?Local, ?URL 133 rdf_url_namespace/2, % +URL, ?Base 134 135 rdf_warm_indexes/0, 136 rdf_warm_indexes/1, % +Indexed 137 rdf_update_duplicates/0, 138 139 rdf_debug/1, % Set verbosity 140 141 rdf_new_literal_map/1, % -Handle 142 rdf_destroy_literal_map/1, % +Handle 143 rdf_reset_literal_map/1, % +Handle 144 rdf_insert_literal_map/3, % +Handle, +Key, +Literal 145 rdf_insert_literal_map/4, % +Handle, +Key, +Literal, -NewKeys 146 rdf_delete_literal_map/3, % +Handle, +Key, +Literal 147 rdf_delete_literal_map/2, % +Handle, +Key 148 rdf_find_literal_map/3, % +Handle, +KeyList, -Literals 149 rdf_keys_in_literal_map/3, % +Handle, +Spec, -Keys 150 rdf_statistics_literal_map/2, % +Handle, +Name(-Arg...) 151 152 rdf_graph_prefixes/2, % ?Graph, -Prefixes 153 rdf_graph_prefixes/3, % ?Graph, -Prefixes, :Filter 154 155 (rdf_meta)/1, % +Heads 156 op(1150, fx, (rdf_meta)) 157 ]). 158:- use_module(library(semweb/rdf_prefixes), 159 [ (rdf_meta)/1, 160 register_file_prefixes/1, 161 rdf_global_id/2, 162 rdf_register_ns/2, 163 % re-exported predicates 164 rdf_global_object/2, 165 rdf_current_ns/2, 166 rdf_prefix/2, 167 rdf_global_term/2, 168 rdf_register_ns/3, 169 rdf_register_prefix/3, 170 rdf_register_prefix/2, 171 rdf_current_prefix/2, 172 rdf_unregister_prefix/1 173 ]). 174 175:- autoload(library(apply),[maplist/2,maplist/3]). 176:- use_module(library(debug),[debug/3,assertion/1]). 177:- autoload(library(error),[must_be/2,existence_error/2]). 178:- autoload(library(gensym),[gensym/2,reset_gensym/1]). 179:- autoload(library(lists), 180 [member/2,flatten/2,list_to_set/2,append/3,select/3]). 181:- autoload(library(memfile), 182 [atom_to_memory_file/2,open_memory_file/4]). 183:- autoload(library(option), 184 [option/2,option/3,merge_options/3,meta_options/3]). 185:- autoload(library(rdf),[process_rdf/3]). 186:- autoload(library(sgml), 187 [ load_structure/3, 188 xml_quote_attribute/3, 189 xml_name/1, 190 xml_quote_cdata/3, 191 xml_is_dom/1, 192 iri_xml_namespace/3, 193 iri_xml_namespace/2 194 ]). 195:- autoload(library(sgml_write),[xml_write/3]). 196:- autoload(library(uri), 197 [ uri_file_name/2, 198 uri_is_global/1, 199 uri_normalized/2, 200 uri_components/2, 201 uri_data/3, 202 uri_data/4 203 ]). 204:- autoload(library(xsdp_types),[xsdp_numeric_uri/2]). 205:- autoload(library(semweb/rdf_cache),[rdf_cache_file/3]). 206 207:- if(exists_source(library(thread))). 208:- autoload(library(thread), [concurrent/3]). 209:- endif. 210 211:- use_foreign_library(foreign(rdf_db)). 212:- public rdf_print_predicate_cloud/2. % print matrix of reachable predicates 213 214:- meta_predicate 215 rdf_transaction(), 216 rdf_transaction(, ), 217 rdf_transaction(, , ), 218 rdf_monitor(, ), 219 rdf_save(, ), 220 rdf_load(, ). 221 222:- predicate_options(rdf_graph_prefixes/3, 3, 223 [ expand(callable+4), 224 filter(callable+3), 225 get_prefix(callable+2), 226 min_count(nonneg) 227 ]). 228:- predicate_options(rdf_load/2, 2, 229 [ base_uri(atom), 230 blank_nodes(oneof([share,noshare])), 231 cache(boolean), 232 concurrent(positive_integer), 233 db(atom), 234 format(oneof([xml,triples,turtle,trig,nquads,ntriples])), 235 graph(atom), 236 multifile(boolean), 237 if(oneof([true,changed,not_loaded])), 238 modified(-float), 239 prefixes(-list), 240 silent(boolean), 241 register_namespaces(boolean) 242 ]). 243:- predicate_options(rdf_save/2, 2, 244 [ graph(atom), 245 db(atom), 246 anon(boolean), 247 base_uri(atom), 248 write_xml_base(boolean), 249 convert_typed_literal(callable), 250 encoding(encoding), 251 document_language(atom), 252 namespaces(list(atom)), 253 xml_attributes(boolean), 254 inline(boolean) 255 ]). 256:- predicate_options(rdf_save_header/2, 2, 257 [ graph(atom), 258 db(atom), 259 namespaces(list(atom)) 260 ]). 261:- predicate_options(rdf_save_subject/3, 3, 262 [ graph(atom), 263 base_uri(atom), 264 convert_typed_literal(callable), 265 document_language(atom) 266 ]). 267:- predicate_options(rdf_transaction/3, 3, 268 [ snapshot(any) 269 ]). 270 271:- discontiguous 272 term_expansion/2.
288 /******************************* 289 * PREFIXES * 290 *******************************/ 291 292% the ns/2 predicate is historically defined in this module. We'll keep 293% that for compatibility reasons. 294 295:- multifile ns/2. 296:- dynamic ns/2. % ID, URL 297 298:- multifile 299 rdf_prefixes:rdf_empty_prefix_cache/2. 300 301rdf_prefixesrdf_empty_prefix_cache(_Prefix, _IRI) :- 302 rdf_empty_prefix_cache. 303 304:- rdf_meta 305 rdf(r,r,o), 306 rdf_has(r,r,o,r), 307 rdf_has(r,r,o), 308 rdf_assert(r,r,o), 309 rdf_retractall(r,r,o), 310 rdf(r,r,o,?), 311 rdf_assert(r,r,o,+), 312 rdf_retractall(r,r,o,?), 313 rdf_reachable(r,r,o), 314 rdf_reachable(r,r,o,+,?), 315 rdf_update(r,r,o,t), 316 rdf_update(r,r,o,+,t), 317 rdf_equal(o,o), 318 rdf_source_location(r,-), 319 rdf_resource(r), 320 rdf_subject(r), 321 rdf_create_graph(r), 322 rdf_graph(r), 323 rdf_graph_property(r,?), 324 rdf_set_graph(r,+), 325 rdf_unload_graph(r), 326 rdf_set_predicate(r, t), 327 rdf_predicate_property(r, -), 328 rdf_estimate_complexity(r,r,r,-), 329 rdf_print_predicate_cloud(r,+).
335rdf_equal(Resource, Resource).343lang_equal(Lang, Lang) :- !. 344lang_equal(Lang1, Lang2) :- 345 downcase_atom(Lang1, LangCannon), 346 downcase_atom(Lang2, LangCannon).
358 /******************************* 359 * BASIC TRIPLE QUERIES * 360 *******************************/
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 breadth-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.
526rdf_subject(Resource) :-
527 rdf_resource(Resource),
528 ( 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.
541 /******************************* 542 * TRIPLE MODIFICATIONS * 543 *******************************/
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).594 /******************************* 595 * COLLECTIONS * 596 *******************************/
602term_expansion(member_prefix(x), 603 member_prefix(Prefix)) :- 604 rdf_db:ns(rdf, NS), 605 atom_concat(NS, '_', Prefix). 606member_prefix(x). 607 608rdf_member_property(P, N) :- 609 integer(N), 610 !, 611 member_prefix(Prefix), 612 atom_concat(Prefix, N, P). 613rdf_member_property(P, N) :- 614 member_prefix(Prefix), 615 atom_concat(Prefix, Sub, P), 616 atom_number(Sub, N). 617 618 619 /******************************* 620 * ANONYMOUS SUBJECTS * 621 *******************************/
629rdf_node(Resource) :-
630 rdf_bnode(Resource).636rdf_bnode(Value) :- 637 repeat, 638 gensym('_:genid', Value), 639 \+ rdf(Value, _, _), 640 \+ rdf(_, _, Value), 641 \+ rdf(_, Value, _), 642 !. 643 644 645 646 /******************************* 647 * TYPES * 648 *******************************/
_:. For backward compatibility reason, __ is also
considered to be a blank node.
667rdf_is_resource(Term) :-
668 atom(Term).675rdf_is_literal(literal(Value)) :- 676 ground(Value). 677 678 /******************************* 679 * LITERALS * 680 *******************************/
| Plain literals | Atom |
| Language tagged literal | Atom holding plain text |
| xsd:string | Atom |
| rdf:XMLLiteral | XML DOM Tree |
| Numeric XSD type | Number |
705:- rdf_meta 706 rdf_literal_value(o, -), 707 typed_value(r, +, -), 708 numeric_value(r, +, -). 709 710rdf_literal_value(literal(String), Value) :- 711 atom(String), 712 !, 713 Value = String. 714rdf_literal_value(literal(lang(_Lang, String)), String). 715rdf_literal_value(literal(type(Type, String)), Value) :- 716 typed_value(Type, String, Value). 717 718typed_value(Numeric, String, Value) :- 719 xsdp_numeric_uri(Numeric, NumType), 720 !, 721 numeric_value(NumType, String, Value). 722typed_value(xsd:string, String, String). 723typed_value(rdf:'XMLLiteral', Value, DOM) :- 724 ( atom(Value) 725 -> setup_call_cleanup( 726 ( atom_to_memory_file(Value, MF), 727 open_memory_file(MF, read, In, [free_on_close(true)]) 728 ), 729 load_structure(stream(In), DOM, [dialect(xml)]), 730 close(In)) 731 ; DOM = Value 732 ). 733 734numeric_value(xsd:integer, String, Value) :- 735 atom_number(String, Value), 736 integer(Value). 737numeric_value(xsd:float, String, Value) :- 738 atom_number(String, Number), 739 Value is float(Number). 740numeric_value(xsd:double, String, Value) :- 741 atom_number(String, Number), 742 Value is float(Number). 743numeric_value(xsd:decimal, String, Value) :- 744 atom_number(String, Value). 745 746 747 /******************************* 748 * SOURCE * 749 *******************************/
757rdf_source_location(Subject, Source) :- 758 findall(Source, rdf(Subject, _, _, Source), Sources), 759 sort(Sources, Unique), 760 member(Source, Unique). 761 762 763 /******************************* 764 * GARBAGE COLLECT * 765 *******************************/
771:- public 772 rdf_create_gc_thread/0. 773 774rdf_create_gc_thread :- 775 thread_create(rdf_gc_loop, _, 776 [ alias('__rdf_GC') 777 ]).
784rdf_gc_loop :- 785 catch(rdf_gc_loop(0), E, recover_gc(E)). 786 787recover_gc('$aborted') :- 788 !, 789 thread_self(Me), 790 thread_detach(Me). 791recover_gc(Error) :- 792 print_message(error, Error), 793 rdf_gc_loop. 794 795rdf_gc_loop(CPU) :- 796 repeat, 797 ( consider_gc(CPU) 798 -> rdf_gc(CPU1), 799 sleep(CPU1) 800 ; sleep(0.1) 801 ), 802 fail.
810rdf_gc(CPU) :-
811 statistics(cputime, CPU0),
812 ( rdf_gc_
813 -> statistics(cputime, CPU1),
814 CPU is CPU1-CPU0,
815 rdf_add_gc_time(CPU)
816 ; CPU = 0.0
817 ).__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.
829rdf_gc :- 830 has_garbage, 831 !, 832 rdf_gc(_), 833 rdf_gc. 834rdf_gc.
840has_garbage :- 841 rdf_gc_info_(Info), 842 has_garbage(Info), 843 !. 844 845has_garbage(Info) :- arg(2, Info, Garbage), Garbage > 0. 846has_garbage(Info) :- arg(3, Info, Reindexed), Reindexed > 0. 847has_garbage(Info) :- arg(4, Info, Optimizable), Optimizable > 0.
854consider_gc(_CPU) :- 855 ( rdf_gc_info_(gc_info(Triples, % Total #triples in DB 856 Garbage, % Garbage triples in DB 857 Reindexed, % Reindexed & not reclaimed 858 Optimizable, % Non-optimized tables 859 _KeepGen, % Oldest active generation 860 _LastGCGen, % Oldest active gen at last GC 861 _ReindexGen, 862 _LastGCReindexGen)) 863 -> ( (Garbage+Reindexed) * 5 > Triples 864 ; Optimizable > 4 865 ) 866 ; print_message(error, rdf(invalid_gc_info)), 867 sleep(10) 868 ), 869 !. 870 871 872 /******************************* 873 * STATISTICS * 874 *******************************/
triples for the interpretation of this value.920rdf_statistics(graphs(Count)) :- 921 rdf_statistics_(graphs(Count)). 922rdf_statistics(triples(Count)) :- 923 rdf_statistics_(triples(Count)). 924rdf_statistics(duplicates(Count)) :- 925 rdf_statistics_(duplicates(Count)). 926rdf_statistics(lingering(Count)) :- 927 rdf_statistics_(lingering(Count)). 928rdf_statistics(resources(Count)) :- 929 rdf_statistics_(resources(Count)). 930rdf_statistics(properties(Count)) :- 931 rdf_statistics_(predicates(Count)). 932rdf_statistics(literals(Count)) :- 933 rdf_statistics_(literals(Count)). 934rdf_statistics(gc(Count, Reclaimed, Reindexed, Time)) :- 935 rdf_statistics_(gc(Count, Reclaimed, Reindexed, Time)). 936rdf_statistics(searched_nodes(Count)) :- 937 rdf_statistics_(searched_nodes(Count)). 938rdf_statistics(lookup(Index, Count)) :- 939 functor(Indexed, indexed, 16), 940 rdf_statistics_(Indexed), 941 index(Index, I), 942 Arg is I + 1, 943 arg(Arg, Indexed, Count), 944 Count \== 0. 945rdf_statistics(hash_quality(Index, Size, Quality,Optimize)) :- 946 rdf_statistics_(hash_quality(List)), 947 member(hash(Place,Size,Quality,Optimize), List), 948 index(Index, Place). 949rdf_statistics(triples_by_graph(Graph, Count)) :- 950 rdf_graph_(Graph, Count). 951 952index(rdf(-,-,-,-), 0). 953index(rdf(+,-,-,-), 1). 954index(rdf(-,+,-,-), 2). 955index(rdf(+,+,-,-), 3). 956index(rdf(-,-,+,-), 4). 957index(rdf(+,-,+,-), 5). 958index(rdf(-,+,+,-), 6). 959index(rdf(+,+,+,-), 7). 960 961index(rdf(-,-,-,+), 8). 962index(rdf(+,-,-,+), 9). 963index(rdf(-,+,-,+), 10). 964index(rdf(+,+,-,+), 11). 965index(rdf(-,-,+,+), 12). 966index(rdf(+,-,+,+), 13). 967index(rdf(-,+,+,+), 14). 968index(rdf(+,+,+,+), 15). 969 970 971 /******************************* 972 * PREDICATES * 973 *******************************/
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.
989rdf_current_predicate(P, DB) :-
990 rdf_current_predicate(P),
991 ( rdf(_,P,_,DB)
992 -> true
993 ).inverse_of(Self).rdf_subject_branch_factor
property, uniqueness of the object value is computed from the
hash key rather than the actual values.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/3.1046rdf_predicate_property(P, Prop) :- 1047 var(P), 1048 !, 1049 rdf_current_predicate(P), 1050 rdf_predicate_property_(P, Prop). 1051rdf_predicate_property(P, Prop) :- 1052 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.
1077 /******************************* 1078 * SNAPSHOTS * 1079 *******************************/
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.1102rdf_current_snapshot(Term) :- 1103 current_blob(Term, rdf_snapshot). 1104 1105 1106 /******************************* 1107 * TRANSACTION * 1108 *******************************/
rdf_transaction(Goal, user, []). See rdf_transaction/3.rdf_transaction(Goal, Id, []). See rdf_transaction/3.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.1144rdf_transaction(Goal) :- 1145 rdf_transaction(Goal, user, []). 1146rdf_transaction(Goal, Id) :- 1147 rdf_transaction(Goal, Id, []).
1158rdf_active_transaction(Id) :-
1159 rdf_active_transactions_(List),
1160 member(Id, List).1166rdf_monitor(Goal, Options) :- 1167 monitor_mask(Options, 0xffff, Mask), 1168 rdf_monitor_(Goal, Mask). 1169 1170monitor_mask([], Mask, Mask). 1171monitor_mask([H|T], Mask0, Mask) :- 1172 update_mask(H, Mask0, Mask1), 1173 monitor_mask(T, Mask1, Mask). 1174 1175update_mask(-X, Mask0, Mask) :- 1176 !, 1177 monitor_mask(X, M), 1178 Mask is Mask0 /\ \M. 1179update_mask(+X, Mask0, Mask) :- 1180 !, 1181 monitor_mask(X, M), 1182 Mask is Mask0 \/ M. 1183update_mask(X, Mask0, Mask) :- 1184 monitor_mask(X, M), 1185 Mask is Mask0 \/ M.
1192 % C-defined broadcasts 1193monitor_mask(assert, 0x0001). 1194monitor_mask(assert(load), 0x0002). 1195monitor_mask(retract, 0x0004). 1196monitor_mask(update, 0x0008). 1197monitor_mask(new_literal, 0x0010). 1198monitor_mask(old_literal, 0x0020). 1199monitor_mask(transaction, 0x0040). 1200monitor_mask(load, 0x0080). 1201monitor_mask(create_graph, 0x0100). 1202monitor_mask(reset, 0x0200). 1203 % prolog defined broadcasts 1204monitor_mask(parse, 0x1000). 1205monitor_mask(unload, 0x1000). % FIXME: Duplicate 1206 % mask for all 1207monitor_mask(all, 0xffff). 1208 1209%rdf_broadcast(Term, MaskName) :- 1210%% monitor_mask(MaskName, Mask), 1211%% rdf_broadcast_(Term, Mask). 1212 1213 1214 /******************************* 1215 * WARM * 1216 *******************************/
1222rdf_warm_indexes :- 1223 findall(Index, rdf_index(Index), Indexes), 1224 rdf_warm_indexes(Indexes). 1225 1226rdf_index(s). 1227rdf_index(p). 1228rdf_index(o). 1229rdf_index(sp). 1230rdf_index(o). 1231rdf_index(po). 1232rdf_index(spo). 1233rdf_index(g). 1234rdf_index(sg). 1235rdf_index(pg).
1246 /******************************* 1247 * DUPLICATES * 1248 *******************************/
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.
1263:- public
1264 rdf_update_duplicates_thread/0.
1270rdf_update_duplicates_thread :-
1271 thread_create(rdf_update_duplicates, _,
1272 [ detached(true),
1273 alias('__rdf_duplicate_detecter')
1274 ]).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.
1288 /******************************* 1289 * QUICK BINARY LOAD/SAVE * 1290 *******************************/
1300:- create_prolog_flag(rdf_triple_format, 3, [type(integer)]). 1301 1302rdf_save_db(File) :- 1303 current_prolog_flag(rdf_triple_format, Version), 1304 setup_call_cleanup( 1305 open(File, write, Out, [type(binary)]), 1306 ( set_stream(Out, record_position(false)), 1307 rdf_save_db_(Out, _, Version) 1308 ), 1309 close(Out)). 1310 1311 1312rdf_save_db(File, Graph) :- 1313 current_prolog_flag(rdf_triple_format, Version), 1314 setup_call_cleanup( 1315 open(File, write, Out, [type(binary)]), 1316 ( set_stream(Out, record_position(false)), 1317 rdf_save_db_(Out, Graph, Version) 1318 ), 1319 close(Out)).
1328rdf_load_db_no_admin(File, Id, Graphs) :-
1329 open(File, read, In, [type(binary)]),
1330 set_stream(In, record_position(false)),
1331 call_cleanup(rdf_load_db_(In, Id, Graphs), close(In)).1342check_loaded_cache(DB, [DB], _Modified) :- !. 1343check_loaded_cache(DB, Graphs, _) :- 1344 print_message(warning, rdf(inconsistent_cache(DB, Graphs))).
1351rdf_load_db(File) :- 1352 uri_file_name(URL, File), 1353 rdf_load_db_no_admin(File, URL, _Graphs). 1354 1355 1356 /******************************* 1357 * LOADING RDF * 1358 *******************************/ 1359 1360:- multifile 1361 rdf_open_hook/8, 1362 rdf_open_decode/4, % +Encoding, +File, -Stream, -Cleanup 1363 rdf_load_stream/3, % +Format, +Stream, +Options 1364 rdf_file_type/2, % ?Extension, ?Format 1365 rdf_storage_encoding/2, % ?Extension, ?Encoding 1366 url_protocol/1. % ?Protocol
rdf_load(FileOrList, []). See rdf_load/2.share (default),
equivalent blank nodes are shared in the same resource.file:// URL when loading
a file or, if the specification is a URL, its normalized
version without the optional #fragment.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)).
1458:- dynamic 1459 rdf_loading/3. % Graph, Queue, Thread 1460 1461rdf_load(Spec) :- 1462 rdf_load(Spec, []). 1463 1464:- if(\+current_predicate(concurrent/3)). 1465concurrent(_, Goals, _) :- 1466 forall(member(G, Goals), call(G)). 1467:- endif. 1468 1469% Note that we kill atom garbage collection. This improves performance 1470% with about 15% loading the LUBM Univ_50 benchmark. 1471 1472rdf_load(Spec, M:Options) :- 1473 must_be(list, Options), 1474 current_prolog_flag(agc_margin, Old), 1475 setup_call_cleanup( 1476 set_prolog_flag(agc_margin, 0), 1477 rdf_load_noagc(Spec, M, Options), 1478 set_prolog_flag(agc_margin, Old)). 1479 1480rdf_load_noagc(List, M, Options) :- 1481 is_list(List), 1482 !, 1483 flatten(List, Inputs), % Compatibility: allow nested lists 1484 maplist(must_be(ground), Inputs), 1485 length(Inputs, Count), 1486 load_jobs(Count, Jobs, Options), 1487 ( Jobs =:= 1 1488 -> forall(member(Spec, Inputs), 1489 rdf_load_one(Spec, M, Options)) 1490 ; maplist(load_goal(Options, M), Inputs, Goals), 1491 concurrent(Jobs, Goals, []) 1492 ). 1493rdf_load_noagc(One, M, Options) :- 1494 must_be(ground, One), 1495 rdf_load_one(One, M, Options). 1496 1497load_goal(Options, M, Spec, rdf_load_one(Spec, M, Options)). 1498 1499load_jobs(_, Jobs, Options) :- 1500 option(concurrent(Jobs), Options), 1501 !, 1502 must_be(positive_integer, Jobs). 1503load_jobs(Count, Jobs, _) :- 1504 current_prolog_flag(cpu_count, CPUs), 1505 CPUs > 0, 1506 !, 1507 Jobs is max(1, min(CPUs, Count)). 1508load_jobs(_, 1, _). 1509 1510 1511rdf_load_one(Spec, M, Options) :- 1512 source_url(Spec, Protocol, SourceURL), 1513 load_graph(SourceURL, Graph, Options), 1514 setup_call_cleanup( 1515 with_mutex(rdf_load_file, 1516 rdf_start_load(SourceURL, Loading)), 1517 rdf_load_file(Loading, Spec, SourceURL, Protocol, 1518 Graph, M, Options), 1519 rdf_end_load(Loading)).
1536rdf_start_load(SourceURL, queue(Queue)) :- 1537 rdf_loading(SourceURL, Queue, LoadThread), 1538 \+ thread_self(LoadThread), 1539 !, 1540 debug(rdf(load), '~p is being loaded by thread ~w; waiting ...', 1541 [ SourceURL, LoadThread]). 1542rdf_start_load(SourceURL, Ref) :- 1543 thread_self(Me), 1544 message_queue_create(Queue), 1545 assertz(rdf_loading(SourceURL, Queue, Me), Ref). 1546 1547rdf_end_load(queue(_)) :- !. 1548rdf_end_load(Ref) :- 1549 clause(rdf_loading(_, Queue, _), _, Ref), 1550 erase(Ref), 1551 thread_send_message(Queue, done), 1552 message_queue_destroy(Queue). 1553 1554rdf_load_file(queue(Queue), _Spec, _SourceURL, _Protocol, _Graph, _M, _Options) :- 1555 !, 1556 catch(thread_get_message(Queue, _), _, true). 1557rdf_load_file(_Ref, _Spec, SourceURL, Protocol, Graph, M, Options) :- 1558 debug(rdf(load), 'RDF: Loading ~q into ~q', [SourceURL, Graph]), 1559 statistics(cputime, T0), 1560 rdf_open_input(SourceURL, Protocol, Graph, 1561 In, Cleanup, Modified, Format, Options), 1562 supported_format(Format, Cleanup), 1563 return_modified(Modified, Options), 1564 ( Modified == not_modified 1565 -> Action = none 1566 ; Modified = cached(CacheFile) 1567 -> do_unload(Graph), 1568 catch(rdf_load_db_no_admin(CacheFile, cache(Graph), Graphs), _, fail), 1569 check_loaded_cache(Graph, Graphs, Modified), 1570 Action = load 1571 ; option(base_uri(BaseURI), Options, Graph), 1572 ( var(BaseURI) 1573 -> BaseURI = SourceURL 1574 ; true 1575 ), 1576 once(phrase(derived_options(Options, NSList), Extra)), 1577 merge_options([ base_uri(BaseURI), 1578 graph(Graph), 1579 format(Format) 1580 | Extra 1581 ], Options, RDFOptions), 1582 ( option(multifile(true), Options) 1583 -> true 1584 ; do_unload(Graph) 1585 ), 1586 graph_modified(Modified, ModifiedStamp), 1587 rdf_set_graph_source(Graph, SourceURL, ModifiedStamp), 1588 call_cleanup(rdf_load_stream(Format, In, M:RDFOptions), 1589 Cleanup), 1590 save_cache(Graph, SourceURL, Options), 1591 register_file_prefixes(NSList), 1592 format_action(Format, Action) 1593 ), 1594 rdf_statistics_(triples(Graph, Triples)), 1595 report_loaded(Action, SourceURL, Graph, Triples, T0, Options). 1596 1597supported_format(Format, _Cleanup) :- 1598 rdf_file_type(_, Format), 1599 !. 1600supported_format(Format, Cleanup) :- 1601 call(Cleanup), 1602 existence_error(rdf_format_plugin, Format). 1603 1604format_action(triples, load) :- !. 1605format_action(_, parsed). 1606 1607save_cache(Graph, SourceURL, Options) :- 1608 option(cache(true), Options, true), 1609 rdf_cache_file(SourceURL, write, CacheFile), 1610 !, 1611 catch(save_cache(Graph, CacheFile), E, 1612 print_message(warning, E)). 1613save_cache(_, _, _). 1614 1615derived_options([], _) --> 1616 []. 1617derived_options([H|T], NSList) --> 1618 ( { H == register_namespaces(true) 1619 ; H == (register_namespaces = true) 1620 } 1621 -> [ namespaces(NSList) ] 1622 ; [] 1623 ), 1624 derived_options(T, NSList). 1625 1626graph_modified(last_modified(Stamp), Stamp). 1627graph_modified(unknown, Stamp) :- 1628 get_time(Stamp). 1629 1630return_modified(Modified, Options) :- 1631 option(modified(M0), Options), 1632 !, 1633 M0 = Modified. 1634return_modified(_, _). 1635 1636 1637 /******************************* 1638 * INPUT HANDLING * 1639 *******************************/ 1640 1641/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1642This section deals with pluggable input sources. The task of the input 1643layer is 1644 1645 * Decide on the graph-name 1646 * Decide on the source-location 1647 * Decide whether loading is needed (if-modified) 1648 * Decide on the serialization in the input 1649 1650The protocol must ensure minimal overhead, in particular for network 1651protocols. E.g. for HTTP we want to make a single call on the server and 1652use If-modified-since to verify that we need not reloading this file. 1653- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
Options processed:
graph(Graph)db(Graph)if(Condition)cache(Cache)format(Format)
1671rdf_open_input(SourceURL, Protocol, Graph,
1672 Stream, Cleanup, Modified, Format, Options) :-
1673 ( option(multifile(true), Options)
1674 -> true
1675 ; option(if(If), Options, changed),
1676 ( If == true
1677 -> true
1678 ; rdf_graph_source_(Graph, SourceURL, HaveModified)
1679 -> true
1680 ; option(cache(true), Options, true),
1681 rdf_cache_file(SourceURL, read, CacheFile)
1682 -> time_file(CacheFile, HaveModified)
1683 ; true
1684 )
1685 ),
1686 option(format(Format), Options, _),
1687 open_input_if_modified(Protocol, SourceURL, HaveModified,
1688 Stream, Cleanup, Modified0, Format, Options),
1689 ( Modified0 == not_modified
1690 -> ( nonvar(CacheFile)
1691 -> Modified = cached(CacheFile)
1692 ; Modified = not_modified
1693 )
1694 ; Modified = Modified0
1695 ).stream(Stream)http)1706source_url(stream(In), stream(In), SourceURL) :- 1707 !, 1708 ( stream_property(In, file_name(File)) 1709 -> to_url(File, SourceURL) 1710 ; gensym('stream://', SourceURL) 1711 ). 1712source_url(Stream, Class, SourceURL) :- 1713 is_stream(Stream), 1714 !, 1715 source_url(stream(Stream), Class, SourceURL). 1716source_url(Spec, Protocol, SourceURL) :- 1717 compound(Spec), 1718 !, 1719 source_file(Spec, Protocol, SourceURL). 1720source_url(FileURL, Protocol, SourceURL) :- % or return FileURL? 1721 uri_file_name(FileURL, File), 1722 !, 1723 source_file(File, Protocol, SourceURL). 1724source_url(SourceURL0, Protocol, SourceURL) :- 1725 is_url(SourceURL0, Protocol, SourceURL), 1726 !. 1727source_url(File, Protocol, SourceURL) :- 1728 source_file(File, Protocol, SourceURL). 1729 1730source_file(Spec, file(SExt), SourceURL) :- 1731 findall(Ext, valid_extension(Ext), Exts), 1732 absolute_file_name(Spec, File, [access(read), extensions([''|Exts])]), 1733 storage_extension(_Plain, SExt, File), 1734 uri_file_name(SourceURL, File). 1735 1736to_url(URL, URL) :- 1737 uri_is_global(URL), 1738 !. 1739to_url(File, URL) :- 1740 absolute_file_name(File, Path), 1741 uri_file_name(URL, Path). 1742 1743storage_extension(Plain, SExt, File) :- 1744 file_name_extension(Plain, SExt, File), 1745 SExt \== '', 1746 rdf_storage_encoding(SExt, _), 1747 !. 1748storage_extension(File, '', File).
graph(Graph) optiondb(Graph) option (backward compatibility)base_uri(BaseURI) option1760load_graph(_Source, Graph, Options) :- 1761 option(multifile(true), Options), 1762 !, 1763 ( ( option(graph(Graph), Options) 1764 -> true 1765 ; option(db(Graph), Options) 1766 ), 1767 ground(Graph) 1768 -> true 1769 ; throw(error(existence_error(option, graph), 1770 context(_, "rdf_load/2: using multifile requires graph"))) 1771 ). 1772load_graph(Source, Graph, Options) :- 1773 ( option(graph(Graph), Options) 1774 ; option(db(Graph), Options) 1775 ), 1776 !, 1777 load_graph2(Source, Graph, Options). 1778load_graph(Source, Graph, Options) :- 1779 load_graph2(Source, Graph, Options). 1780 1781load_graph2(_, Graph, _) :- 1782 ground(Graph), 1783 !. 1784load_graph2(_Source, Graph, Options) :- 1785 option(base_uri(Graph), Options), 1786 Graph \== [], 1787 ground(Graph), 1788 !. 1789load_graph2(Source, Graph, _) :- 1790 load_graph(Source, Graph). 1791 1792load_graph(SourceURL, BaseURI) :- 1793 file_name_extension(BaseURI, Ext, SourceURL), 1794 rdf_storage_encoding(Ext, _), 1795 !. 1796load_graph(SourceURL, SourceURL). 1797 1798 1799open_input_if_modified(stream(In), SourceURL, _, In, true, 1800 unknown, Format, _) :- 1801 !, 1802 ( var(Format) 1803 -> guess_format(SourceURL, Format) 1804 ; true 1805 ). 1806open_input_if_modified(file(SExt), SourceURL, HaveModified, Stream, Cleanup, 1807 Modified, Format, _) :- 1808 !, 1809 uri_file_name(SourceURL, File), 1810 ( SExt == '' -> Plain = File; file_name_extension(Plain, SExt, File)), 1811 time_file(File, LastModified), 1812 ( nonvar(HaveModified), 1813 HaveModified >= LastModified 1814 -> Modified = not_modified, 1815 Cleanup = true 1816 ; storage_open(SExt, File, Stream, Cleanup), 1817 Modified = last_modified(LastModified), 1818 ( var(Format) 1819 -> guess_format(Plain, Format) 1820 ; true 1821 ) 1822 ). 1823open_input_if_modified(file, SourceURL, HaveModified, Stream, Cleanup, 1824 Modified, Format, Options) :- 1825 !, 1826 open_input_if_modified(file(''), SourceURL, HaveModified, 1827 Stream, Cleanup, 1828 Modified, Format, Options). 1829open_input_if_modified(Protocol, SourceURL, HaveModified, Stream, Cleanup, 1830 Modified, Format, Options) :- 1831 rdf_open_hook(Protocol, SourceURL, HaveModified, Stream, Cleanup, 1832 Modified, Format, Options). 1833 1834guess_format(File, Format) :- 1835 file_name_extension(_, Ext, File), 1836 ( rdf_file_type(Ext, Format) 1837 -> true 1838 ; Format = xml, 1839 print_message(warning, rdf(guess_format(Ext))) 1840 ).
1848storage_open('', File, Stream, close(Stream)) :- 1849 !, 1850 open(File, read, Stream, [type(binary)]). 1851storage_open(Ext, File, Stream, Cleanup) :- 1852 rdf_storage_encoding(Ext, Encoding), 1853 rdf_open_decode(Encoding, File, Stream, Cleanup). 1854 1855valid_extension(Ext) :- 1856 rdf_file_type(Ext, _). 1857valid_extension(Ext) :- 1858 rdf_storage_encoding(Ext, _).
1868is_url(URL, Scheme, FetchURL) :- 1869 atom(URL), 1870 uri_is_global(URL), 1871 uri_normalized(URL, URL1), % case normalization 1872 uri_components(URL1, Components), 1873 uri_data(scheme, Components, Scheme0), 1874 url_protocol(Scheme0), 1875 !, 1876 Scheme = Scheme0, 1877 uri_data(fragment, Components, _, Components1), 1878 uri_components(FetchURL, Components1). 1879 1880url_protocol(file). % built-in
1888rdf_file_type(xml, xml). 1889rdf_file_type(rdf, xml). 1890rdf_file_type(rdfs, xml). 1891rdf_file_type(owl, xml). 1892rdf_file_type(htm, xhtml). 1893rdf_file_type(html, xhtml). 1894rdf_file_type(xhtml, xhtml). 1895rdf_file_type(trp, triples).
1902rdf_storage_encoding('', plain).1911rdf_load_stream(xml, Stream, Options) :- 1912 !, 1913 graph(Options, Graph), 1914 rdf_transaction(load_stream(Stream, Options), 1915 parse(Graph)). 1916rdf_load_stream(xhtml, Stream, M:Options) :- 1917 !, 1918 graph(Options, Graph), 1919 rdf_transaction(load_stream(Stream, M:[embedded(true)|Options]), 1920 parse(Graph)). 1921rdf_load_stream(triples, Stream, Options) :- 1922 !, 1923 graph(Options, Graph), 1924 rdf_load_db_(Stream, Graph, _Graphs). 1925 1926load_stream(Stream, M:Options) :- 1927 process_rdf(Stream, assert_triples, M:Options), 1928 option(graph(Graph), Options), 1929 rdf_graph_clear_modified_(Graph).
1934report_loaded(none, _, _, _, _, _) :- !. 1935report_loaded(Action, Source, DB, Triples, T0, Options) :- 1936 statistics(cputime, T1), 1937 Time is T1 - T0, 1938 ( option(silent(true), Options) 1939 -> Level = silent 1940 ; Level = informational 1941 ), 1942 print_message(Level, 1943 rdf(loaded(Action, Source, DB, Triples, Time))).
1956rdf_unload(Spec) :- 1957 source_url(Spec, _Protocol, SourceURL), 1958 rdf_graph_source_(Graph, SourceURL, _), 1959 !, 1960 rdf_unload_graph(Graph). 1961rdf_unload(Graph) :- 1962 atom(Graph), 1963 rdf_graph(Graph), 1964 !, 1965 warn_deprecated_unload(Graph), 1966 rdf_unload_graph(Graph). 1967rdf_unload(_). 1968 1969:- dynamic 1970 warned/0. 1971 1972warn_deprecated_unload(_) :- 1973 warned, 1974 !. 1975warn_deprecated_unload(Graph) :- 1976 assertz(warned), 1977 print_message(warning, rdf(deprecated(rdf_unload(Graph)))).
1985rdf_unload_graph(Graph) :- 1986 must_be(atom, Graph), 1987 ( rdf_graph(Graph) 1988 -> rdf_transaction(do_unload(Graph), unload(Graph)) 1989 ; true 1990 ). 1991 1992do_unload(Graph) :- 1993 ( rdf_graph_(Graph, Triples), 1994 Triples > 0 1995 -> rdf_retractall(_,_,_,Graph) 1996 ; true 1997 ), 1998 rdf_destroy_graph(Graph). 1999 2000 /******************************* 2001 * GRAPH QUERIES * 2002 *******************************/
2014rdf_graph(Graph) :-
2015 rdf_graph_(Graph, _Triples).
2023rdf_source(Graph, SourceURL) :-
2024 rdf_graph(Graph),
2025 rdf_graph_source_(Graph, SourceURL, _Modified).
2033rdf_source(SourceURL) :-
2034 rdf_source(_Graph, SourceURL).2041rdf_make :- 2042 findall(Source-Graph, modified_graph(Source, Graph), Modified), 2043 forall(member(Source-Graph, Modified), 2044 catch(rdf_load(Source, [graph(Graph), if(changed)]), E, 2045 print_message(error, E))). 2046 2047modified_graph(SourceURL, Graph) :- 2048 rdf_graph(Graph), 2049 rdf_graph_source_(Graph, SourceURL, Modified), 2050 \+ sub_atom(SourceURL, 0, _, _, 'stream://'), 2051 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:
true if the graph is persistent.2079rdf_graph_property(Graph, Property) :- 2080 rdf_graph(Graph), 2081 property_of_graph(Property, Graph). 2082 2083:- multifile 2084 property_of_graph/2. 2085 2086property_of_graph(hash(Hash), Graph) :- 2087 rdf_md5(Graph, Hash). 2088property_of_graph(modified(Boolean), Graph) :- 2089 rdf_graph_modified_(Graph, Boolean, _). 2090property_of_graph(source(URL), Graph) :- 2091 rdf_graph_source_(Graph, URL, _). 2092property_of_graph(source_last_modified(Time), Graph) :- 2093 rdf_graph_source_(Graph, _, Time), 2094 Time > 0.0. 2095property_of_graph(triples(Count), Graph) :- 2096 rdf_graph_(Graph, Count).
2105rdf_set_graph(Graph, modified(Modified)) :-
2106 must_be(oneof([false]), Modified),
2107 rdf_graph_clear_modified_(Graph).
2114save_cache(DB, Cache) :-
2115 current_prolog_flag(rdf_triple_format, Version),
2116 setup_call_cleanup(
2117 catch(open(Cache, write, CacheStream, [type(binary)]), _, fail),
2118 rdf_save_db_(CacheStream, DB, Version),
2119 close(CacheStream)).2127assert_triples([], _). 2128assert_triples([rdf(S,P,O)|T], DB) :- 2129 !, 2130 rdf_assert(S, P, O, DB), 2131 assert_triples(T, DB). 2132assert_triples([H|_], _) :- 2133 throw(error(type_error(rdf_triple, H), _)). 2134 2135 2136 /******************************* 2137 * RESET * 2138 *******************************/
2151rdf_reset_db :- 2152 reset_gensym('_:genid'), 2153 rdf_reset_db_. 2154 2155 2156 /******************************* 2157 * SAVE RDF * 2158 *******************************/
rdf_save(Out, []). See rdf_save/2 for details.false (default true) do not save blank nodes that do
not appear (indirectly) as object of a named resource.write_xml_base option.xml:lang saved with rdf:RDF element.true (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>.2220:- thread_local 2221 named_anon/2, % +Resource, -Id 2222 inlined/1. % +Resource 2223 2224rdf_save(File) :- 2225 rdf_save2(File, []). 2226 2227rdf_save(Spec, M:Options0) :- 2228 is_list(Options0), 2229 !, 2230 meta_options(save_meta_option, M:Options0, Options), 2231 to_file(Spec, File), 2232 rdf_save2(File, Options). 2233rdf_save(Spec, _:DB) :- 2234 atom(DB), % backward compatibility 2235 !, 2236 to_file(Spec, File), 2237 rdf_save2(File, [graph(DB)]). 2238 2239save_meta_option(convert_typed_literal). 2240 2241to_file(URL, File) :- 2242 atom(URL), 2243 uri_file_name(URL, File), 2244 !. 2245to_file(File, File). 2246 2247rdf_save2(File, Options) :- 2248 option(encoding(Encoding), Options, utf8), 2249 valid_encoding(Encoding), 2250 open_output(File, Encoding, Out, Close), 2251 flag(rdf_db_saved_subjects, OSavedSubjects, 0), 2252 flag(rdf_db_saved_triples, OSavedTriples, 0), 2253 call_cleanup(rdf_do_save(Out, Options), 2254 Reason, 2255 cleanup_save(Reason, 2256 File, 2257 OSavedSubjects, 2258 OSavedTriples, 2259 Close)). 2260 2261open_output(stream(Out), Encoding, Out, Cleanup) :- 2262 !, 2263 stream_property(Out, encoding(Old)), 2264 ( ( Old == Encoding 2265 ; Old == wchar_t % Internal encoding 2266 ) 2267 -> Cleanup = true 2268 ; set_stream(Out, encoding(Encoding)), 2269 Cleanup = set_stream(Out, encoding(Old)) 2270 ). 2271open_output(File, Encoding, Out, 2272 close(Out)) :- 2273 open(File, write, Out, [encoding(Encoding)]). 2274 2275valid_encoding(Enc) :- 2276 ( xml_encoding_name(Enc, _) 2277 -> true 2278 ; throw(error(domain_error(encoding, Enc), _)) 2279 ). 2280 2281 2282cleanup_save(Reason, 2283 File, 2284 OSavedSubjects, 2285 OSavedTriples, 2286 Close) :- 2287 call(Close), 2288 flag(rdf_db_saved_subjects, SavedSubjects, OSavedSubjects), 2289 flag(rdf_db_saved_triples, SavedTriples, OSavedTriples), 2290 retractall(named_anon(_, _)), 2291 retractall(inlined(_)), 2292 ( Reason == exit 2293 -> print_message(informational, 2294 rdf(saved(File, SavedSubjects, SavedTriples))) 2295 ; format(user_error, 'Reason = ~w~n', [Reason]) 2296 ). 2297 2298rdf_do_save(Out, Options0) :- 2299 rdf_save_header(Out, Options0, Options), 2300 graph(Options, DB), 2301 ( option(sorted(true), Options, false) 2302 -> ( var(DB) 2303 -> setof(Subject, rdf_subject(Subject), Subjects) 2304 ; findall(Subject, rdf(Subject, _, _, DB:_), SubjectList), 2305 sort(SubjectList, Subjects) 2306 ), 2307 forall(member(Subject, Subjects), 2308 rdf_save_non_anon_subject(Out, Subject, Options)) 2309 ; forall(rdf_subject_in_graph(Subject, DB), 2310 rdf_save_non_anon_subject(Out, Subject, Options)) 2311 ), 2312 rdf_save_footer(Out), 2313 !. % dubious cut; without the 2314 % cleanup handlers isn't called!?
2325rdf_subject_in_graph(Subject, DB) :- 2326 var(DB), 2327 !, 2328 rdf_subject(Subject). 2329rdf_subject_in_graph(Subject, DB) :- 2330 rdf_statistics(triples(AllTriples)), 2331 rdf_graph_property(DB, triples(DBTriples)), 2332 DBTriples > AllTriples // 10, 2333 !, 2334 rdf_resource(Subject), 2335 ( rdf(Subject, _, _, DB:_) 2336 -> true 2337 ). 2338rdf_subject_in_graph(Subject, DB) :- 2339 findall(Subject, rdf(Subject, _, _, DB:_), SubjectList), 2340 list_to_set(SubjectList, Subjects), 2341 member(Subject, Subjects). 2342 2343 2344graph(Options0, DB) :- 2345 strip_module(Options0, _, Options), 2346 ( memberchk(graph(DB0), Options) 2347 -> DB = DB0 2348 ; memberchk(db(DB0), Options) 2349 -> DB = DB0 2350 ; true % leave unbound 2351 ).
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.2376rdf_save_header(Out, Options) :- 2377 rdf_save_header(Out, Options, _). 2378 2379rdf_save_header(Out, Options, OptionsOut) :- 2380 is_list(Options), 2381 !, 2382 option(encoding(Enc), Options, utf8), 2383 xml_encoding(Enc, Encoding), 2384 format(Out, '<?xml version=\'1.0\' encoding=\'~w\'?>~n', [Encoding]), 2385 format(Out, '<!DOCTYPE rdf:RDF [', []), 2386 header_namespaces(Options, NSIdList), 2387 nsmap(NSIdList, NsMap), 2388 append(Options, [nsmap(NsMap)], OptionsOut), 2389 forall(member(Id=URI, NsMap), 2390 ( xml_quote_attribute(URI, NSText0, Enc), 2391 xml_escape_parameter_entity(NSText0, NSText), 2392 format(Out, '~N <!ENTITY ~w \'~w\'>', [Id, NSText]) 2393 )), 2394 format(Out, '~N]>~n~n', []), 2395 format(Out, '<rdf:RDF', []), 2396 ( member(Id, NSIdList), 2397 format(Out, '~N xmlns:~w="&~w;"~n', [Id, Id]), 2398 fail 2399 ; true 2400 ), 2401 ( option(base_uri(Base), Options), 2402 option(write_xml_base(true), Options, true) 2403 -> xml_quote_attribute(Base, BaseText, Enc), 2404 format(Out, '~N xml:base="~w"~n', [BaseText]) 2405 ; true 2406 ), 2407 ( memberchk(document_language(Lang), Options) 2408 -> format(Out, '~N xml:lang="~w"', [Lang]) 2409 ; true 2410 ), 2411 format(Out, '>~n', []). 2412rdf_save_header(Out, FileRef, OptionsOut) :- % compatibility 2413 atom(FileRef), 2414 rdf_save_header(Out, [graph(FileRef)], OptionsOut). 2415 2416xml_encoding(Enc, Encoding) :- 2417 ( xml_encoding_name(Enc, Encoding) 2418 -> true 2419 ; throw(error(domain_error(rdf_encoding, Enc), _)) 2420 ). 2421 2422xml_encoding_name(ascii, 'US-ASCII'). 2423xml_encoding_name(iso_latin_1, 'ISO-8859-1'). 2424xml_encoding_name(utf8, 'UTF-8').
2431nsmap([], []). 2432nsmap([Id|T0], [Id=URI|T]) :- 2433 ns(Id, URI), 2434 nsmap(T0, T).
2440xml_escape_parameter_entity(In, Out) :- 2441 sub_atom(In, _, _, _, '%'), 2442 !, 2443 atom_codes(In, Codes), 2444 phrase(escape_parent(Codes), OutCodes), 2445 atom_codes(Out, OutCodes). 2446xml_escape_parameter_entity(In, In). 2447 2448escape_parent([]) --> []. 2449escape_parent([H|T]) --> 2450 ( { H == 37 } 2451 -> "%" 2452 ; [H] 2453 ), 2454 escape_parent(T).
2461header_namespaces(Options, List) :- 2462 memberchk(namespaces(NSL0), Options), 2463 !, 2464 sort([rdf,rdfs|NSL0], List). 2465header_namespaces(Options, List) :- 2466 graph(Options, DB), 2467 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)
2505:- thread_local 2506 graph_prefix/3. 2507:- meta_predicate 2508 rdf_graph_prefixes(, , ). 2509 2510rdf_graph_prefixes(Graph, List) :- 2511 rdf_graph_prefixes(Graph, List, []). 2512 2513rdf_graph_prefixes(Graph, List, M:QOptions) :- 2514 is_list(QOptions), 2515 !, 2516 meta_options(is_meta, M:QOptions, Options), 2517 option(filter(Filter), Options, true), 2518 option(expand(Expand), Options, rdf_db), 2519 option(min_count(MinCount), Options, 1), 2520 option(get_prefix(GetPrefix), Options, iri_xml_namespace), 2521 call_cleanup(prefixes(Expand, Graph, Prefixes, Filter, MinCount, GetPrefix), 2522 retractall(graph_prefix(_,_,_))), 2523 sort(Prefixes, List). 2524rdf_graph_prefixes(Graph, List, M:Filter) :- 2525 rdf_graph_prefixes(Graph, List, M:[filter(Filter)]). 2526 2527is_meta(filter). 2528is_meta(expand). 2529is_meta(get_prefix). 2530 2531 2532prefixes(Expand, Graph, Prefixes, Filter, MinCount, GetPrefix) :- 2533 ( call(Expand, S, P, O, Graph), 2534 add_ns(subject, GetPrefix, Filter, S, MinCount, s(S)), 2535 add_ns(predicate, GetPrefix, Filter, P, MinCount, sp(S,P)), 2536 add_ns_obj(GetPrefix, Filter, O, MinCount, spo(S,P,O)), 2537 fail 2538 ; true 2539 ), 2540 findall(Prefix, graph_prefix(Prefix, MinCount, _), Prefixes). 2541 2542add_ns(Where, GetPrefix, Filter, S, MinCount, Context) :- 2543 \+ rdf_is_bnode(S), 2544 call(GetPrefix, S, Full), 2545 Full \== '', 2546 !, 2547 ( graph_prefix(Full, MinCount, _) 2548 -> true 2549 ; Filter == true 2550 -> add_ns(Full, Context) 2551 ; call(Filter, Where, Full, S) 2552 -> add_ns(Full, Context) 2553 ; true 2554 ). 2555add_ns(_, _, _, _, _, _). 2556 2557add_ns(Full, Context) :- 2558 graph_prefix(Full, _, Contexts), 2559 memberchk(Context, Contexts), 2560 !. 2561add_ns(Full, Context) :- 2562 retract(graph_prefix(Full, C0, Contexts)), 2563 !, 2564 C1 is C0+1, 2565 asserta(graph_prefix(Full, C1, [Context|Contexts])). 2566add_ns(Full, _) :- 2567 ns(_, Full), 2568 !, 2569 asserta(graph_prefix(Full, _, _)). 2570add_ns(Full, Context) :- 2571 asserta(graph_prefix(Full, 1, [Context])). 2572 2573 2574add_ns_obj(GetPrefix, Filter, O, MinCount, Context) :- 2575 atom(O), 2576 !, 2577 add_ns(object, GetPrefix, Filter, O, MinCount, Context). 2578add_ns_obj(GetPrefix, Filter, literal(type(Type, _)), MinCount, _) :- 2579 atom(Type), 2580 !, 2581 add_ns(type, GetPrefix, Filter, Type, MinCount, t(Type)). 2582add_ns_obj(_, _, _, _, _).
2592used_namespace_entities(List, Graph) :- 2593 decl_used_predicate_ns(Graph), 2594 used_namespaces(List, Graph). 2595 2596used_namespaces(List, DB) :- 2597 rdf_graph_prefixes(DB, FullList), 2598 ns_abbreviations(FullList, List0), 2599 sort([rdf|List0], List). 2600 2601ns_abbreviations([], []). 2602ns_abbreviations([H0|T0], [H|T]) :- 2603 ns(H, H0), 2604 !, 2605 ns_abbreviations(T0, T). 2606ns_abbreviations([_|T0], T) :- 2607 ns_abbreviations(T0, T). 2608 2609 2610/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2611For every URL used as a predicate we *MUST* define a namespace as we 2612cannot use names holding /, :, etc. as XML identifiers. 2613- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ 2614 2615:- thread_local 2616 predicate_ns/2. 2617 2618decl_used_predicate_ns(DB) :- 2619 retractall(predicate_ns(_,_)), 2620 ( rdf_current_predicate(P, DB), 2621 decl_predicate_ns(P), 2622 fail 2623 ; true 2624 ). 2625 2626decl_predicate_ns(Pred) :- 2627 predicate_ns(Pred, _), 2628 !. 2629decl_predicate_ns(Pred) :- 2630 rdf_global_id(NS:Local, Pred), 2631 xml_name(Local), 2632 !, 2633 assert(predicate_ns(Pred, NS)). 2634decl_predicate_ns(Pred) :- 2635 atom_codes(Pred, Codes), 2636 append(NSCodes, LocalCodes, Codes), 2637 xml_codes(LocalCodes), 2638 !, 2639 ( NSCodes \== [] 2640 -> atom_codes(NS, NSCodes), 2641 ( ns(Id, NS) 2642 -> assert(predicate_ns(Pred, Id)) 2643 ; between(1, infinite, N), 2644 atom_concat(ns, N, Id), 2645 \+ ns(Id, _) 2646 -> rdf_register_ns(Id, NS), 2647 print_message(informational, 2648 rdf(using_namespace(Id, NS))) 2649 ), 2650 assert(predicate_ns(Pred, Id)) 2651 ; assert(predicate_ns(Pred, -)) % no namespace used 2652 ). 2653 2654xml_codes([]). 2655xml_codes([H|T]) :- 2656 xml_code(H), 2657 xml_codes(T). 2658 2659xml_code(X) :- 2660 code_type(X, csym), 2661 !. 2662xml_code(0'-). % Match 0'-
2671rdf_save_footer(Out) :-
2672 retractall(named_anon(_, _)),
2673 retractall(inlined(_)),
2674 format(Out, '</rdf:RDF>~n', []).anon(false)
is present in the Options list.2681rdf_save_non_anon_subject(_Out, Subject, Options) :- 2682 rdf_is_bnode(Subject), 2683 ( memberchk(anon(false), Options) 2684 ; graph(Options, DB), 2685 rdf_db(_, _, Subject, DB) 2686 ), 2687 !. 2688rdf_save_non_anon_subject(Out, Subject, Options) :- 2689 rdf_save_subject(Out, Subject, Options), 2690 flag(rdf_db_saved_subjects, X, X+1).
2705rdf_save_subject(Out, Subject, Options) :- 2706 is_list(Options), 2707 !, 2708 option(base_uri(BaseURI), Options, '-'), 2709 ( rdf_save_subject(Out, Subject, BaseURI, 0, Options) 2710 -> format(Out, '~n', []) 2711 ; throw(error(rdf_save_failed(Subject), 'Internal error')) 2712 ). 2713rdf_save_subject(Out, Subject, DB) :- 2714 ( var(DB) 2715 -> rdf_save_subject(Out, Subject, []) 2716 ; rdf_save_subject(Out, Subject, [graph(DB)]) 2717 ).
2727rdf_save_subject(_, Subject, _, _, _) :- 2728 inlined(Subject), 2729 !. 2730rdf_save_subject(Out, Subject, BaseURI, Indent, Options) :- 2731 do_save_subject(Out, Subject, BaseURI, Indent, Options). 2732 2733do_save_subject(Out, Subject, BaseURI, Indent, Options) :- 2734 graph(Options, DB), 2735 findall(Pred=Object, rdf_db(Subject, Pred, Object, DB), Atts0), 2736 sort(Atts0, Atts), % remove duplicates 2737 length(Atts, L), 2738 ( length(Atts0, L0), 2739 Del is L0-L, 2740 Del > 0 2741 -> print_message(informational, 2742 rdf(save_removed_duplicates(Del, Subject))) 2743 ; true 2744 ), 2745 rdf_save_subject(Out, Subject, BaseURI, Atts, Indent, Options), 2746 flag(rdf_db_saved_triples, X, X+L). 2747 2748rdf_db(Subject, Pred, Object, DB) :- 2749 var(DB), 2750 !, 2751 rdf(Subject, Pred, Object). 2752rdf_db(Subject, Pred, Object, DB) :- 2753 rdf(Subject, Pred, Object, DB:_).
2760rdf_save_subject(Out, Subject, BaseURI, Atts, Indent, Options) :- 2761 rdf_equal(rdf:type, RdfType), 2762 select(RdfType=Type, Atts, Atts1), 2763 \+ rdf_is_bnode(Type), 2764 rdf_id(Type, BaseURI, TypeId), 2765 xml_is_name(TypeId), 2766 !, 2767 format(Out, '~*|<', [Indent]), 2768 rdf_write_id(Out, TypeId), 2769 save_about(Out, BaseURI, Subject, Options), 2770 save_attributes(Atts1, BaseURI, Out, TypeId, Indent, Options). 2771rdf_save_subject(Out, Subject, BaseURI, Atts, Indent, Options) :- 2772 format(Out, '~*|<rdf:Description', [Indent]), 2773 save_about(Out, BaseURI, Subject, Options), 2774 save_attributes(Atts, BaseURI, Out, rdf:'Description', Indent, Options). 2775 2776xml_is_name(_NS:Atom) :- 2777 !, 2778 xml_name(Atom). 2779xml_is_name(Atom) :- 2780 xml_name(Atom).
2787save_about(Out, _BaseURI, Subject, _Options) :- 2788 rdf_is_bnode(Subject), 2789 !, 2790 ( named_anon(Subject, NodeID) 2791 -> format(Out, ' rdf:nodeID="~w"', [NodeID]) 2792 ; true 2793 ). 2794save_about(Out, BaseURI, Subject, Options) :- 2795 option(encoding(Encoding), Options, utf8), 2796 rdf_value(Subject, BaseURI, QSubject, Encoding), 2797 format(Out, ' rdf:about="~w"', [QSubject]).
2805save_attributes(Atts, BaseURI, Out, Element, Indent, Options) :-
2806 split_attributes(Atts, InTag, InBody, Options),
2807 SubIndent is Indent + 2,
2808 save_attributes2(InTag, BaseURI, tag, Out, SubIndent, Options),
2809 ( InBody == []
2810 -> format(Out, '/>~n', [])
2811 ; format(Out, '>~n', []),
2812 save_attributes2(InBody, BaseURI, body, Out, SubIndent, Options),
2813 format(Out, '~N~*|</', [Indent]),
2814 rdf_write_id(Out, Element),
2815 format(Out, '>~n', [])
2816 ).2824split_attributes(Atts, [], Atts, Options) :- 2825 option(xml_attributes(false), Options), 2826 !. 2827split_attributes(Atts, HeadAttr, BodyAttr, _) :- 2828 duplicate_attributes(Atts, Dupls, Singles), 2829 simple_literal_attributes(Singles, HeadAttr, Rest), 2830 append(Dupls, Rest, BodyAttr).
2837duplicate_attributes([], [], []). 2838duplicate_attributes([H|T], Dupls, Singles) :- 2839 H = (Name=_), 2840 named_attributes(Name, T, D, R), 2841 D \== [], 2842 append([H|D], Dupls2, Dupls), 2843 !, 2844 duplicate_attributes(R, Dupls2, Singles). 2845duplicate_attributes([H|T], Dupls2, [H|Singles]) :- 2846 duplicate_attributes(T, Dupls2, Singles). 2847 2848named_attributes(_, [], [], []) :- !. 2849named_attributes(Name, [H|T], D, R) :- 2850 ( H = (Name=_) 2851 -> D = [H|DT], 2852 named_attributes(Name, T, DT, R) 2853 ; R = [H|RT], 2854 named_attributes(Name, T, D, RT) 2855 ).
2862simple_literal_attributes([], [], []). 2863simple_literal_attributes([H|TA], [H|TI], B) :- 2864 in_tag_attribute(H), 2865 !, 2866 simple_literal_attributes(TA, TI, B). 2867simple_literal_attributes([H|TA], I, [H|TB]) :- 2868 simple_literal_attributes(TA, I, TB). 2869 2870in_tag_attribute(_=literal(Text)) :- 2871 atom(Text), % may not have lang qualifier 2872 atom_length(Text, Len), 2873 Len < 60.
2879save_attributes2([], _, _, _, _, _). 2880save_attributes2([H|T], BaseURI, Where, Out, Indent, Options) :- 2881 save_attribute(Where, H, BaseURI, Out, Indent, Options), 2882 save_attributes2(T, BaseURI, Where, Out, Indent, Options). 2883 2884save_attribute(tag, Name=literal(Value), BaseURI, Out, Indent, Options) :- 2885 AttIndent is Indent + 2, 2886 rdf_id(Name, BaseURI, NameText), 2887 option(encoding(Encoding), Options, utf8), 2888 xml_quote_attribute(Value, QVal, Encoding), 2889 format(Out, '~N~*|', [AttIndent]), 2890 rdf_write_id(Out, NameText), 2891 format(Out, '="~w"', [QVal]). 2892save_attribute(body, Name=literal(Literal0), BaseURI, Out, Indent, Options) :- 2893 !, 2894 rdf_id(Name, BaseURI, NameText), 2895 ( memberchk(convert_typed_literal(Converter), Options), 2896 call(Converter, Type, Content, Literal0) 2897 -> Literal = type(Type, Content) 2898 ; Literal = Literal0 2899 ), 2900 save_body_literal(Literal, NameText, BaseURI, Out, Indent, Options). 2901save_attribute(body, Name=Value, BaseURI, Out, Indent, Options) :- 2902 rdf_is_bnode(Value), 2903 !, 2904 rdf_id(Name, BaseURI, NameText), 2905 format(Out, '~N~*|<', [Indent]), 2906 rdf_write_id(Out, NameText), 2907 ( named_anon(Value, NodeID) 2908 -> format(Out, ' rdf:nodeID="~w"/>', [NodeID]) 2909 ; ( rdf(S1, Name, Value), 2910 rdf(S2, P2, Value), 2911 (S1 \== S2 ; Name \== P2) 2912 -> predicate_property(named_anon(_,_), number_of_clauses(N)), 2913 atom_concat('bn', N, NodeID), 2914 assertz(named_anon(Value, NodeID)) 2915 ; true 2916 ), 2917 SubIndent is Indent + 2, 2918 ( rdf_collection(Value) 2919 -> save_about(Out, BaseURI, Value, Options), 2920 format(Out, ' rdf:parseType="Collection">~n', []), 2921 rdf_save_list(Out, Value, BaseURI, SubIndent, Options) 2922 ; format(Out, '>~n', []), 2923 rdf_save_subject(Out, Value, BaseURI, SubIndent, Options) 2924 ), 2925 format(Out, '~N~*|</', [Indent]), 2926 rdf_write_id(Out, NameText), 2927 format(Out, '>~n', []) 2928 ). 2929save_attribute(body, Name=Value, BaseURI, Out, Indent, Options) :- 2930 option(inline(true), Options), 2931 has_attributes(Value, Options), 2932 \+ inlined(Value), 2933 !, 2934 assertz(inlined(Value)), 2935 rdf_id(Name, BaseURI, NameText), 2936 format(Out, '~N~*|<', [Indent]), 2937 rdf_write_id(Out, NameText), 2938 SubIndent is Indent + 2, 2939 ( rdf_collection(Value) 2940 -> save_about(Out, BaseURI, Value, Options), 2941 format(Out, ' rdf:parseType="Collection">~n', []), 2942 rdf_save_list(Out, Value, BaseURI, SubIndent, Options) 2943 ; format(Out, '>~n', []), 2944 do_save_subject(Out, Value, BaseURI, SubIndent, Options) 2945 ), 2946 format(Out, '~N~*|</', [Indent]), 2947 rdf_write_id(Out, NameText), 2948 format(Out, '>~n', []). 2949save_attribute(body, Name=Value, BaseURI, Out, Indent, Options) :- 2950 option(encoding(Encoding), Options, utf8), 2951 rdf_value(Value, BaseURI, QVal, Encoding), 2952 rdf_id(Name, BaseURI, NameText), 2953 format(Out, '~N~*|<', [Indent]), 2954 rdf_write_id(Out, NameText), 2955 format(Out, ' rdf:resource="~w"/>', [QVal]). 2956 2957has_attributes(URI, Options) :- 2958 graph(Options, DB), 2959 rdf_db(URI, _, _, DB), 2960 !.
2965save_body_literal(lang(Lang, Value), 2966 NameText, BaseURI, Out, Indent, Options) :- 2967 !, 2968 format(Out, '~N~*|<', [Indent]), 2969 rdf_write_id(Out, NameText), 2970 ( memberchk(document_language(Lang), Options) 2971 -> write(Out, '>') 2972 ; rdf_id(Lang, BaseURI, LangText), 2973 format(Out, ' xml:lang="~w">', [LangText]) 2974 ), 2975 save_attribute_value(Value, Out, Options), 2976 write(Out, '</'), rdf_write_id(Out, NameText), write(Out, '>'). 2977save_body_literal(type(Type, DOM), 2978 NameText, _BaseURI, Out, Indent, Options) :- 2979 rdf_equal(Type, rdf:'XMLLiteral'), 2980 !, 2981 ( atom(DOM) 2982 -> format(Out, '~N~*|<', [Indent]), 2983 rdf_write_id(Out, NameText), 2984 format(Out, ' rdf:parseType="Literal">~w</', [DOM]), 2985 rdf_write_id(Out, NameText), write(Out, '>') 2986 ; save_xml_literal(DOM, NameText, Out, Indent, Options) 2987 ). 2988save_body_literal(type(Type, Value), 2989 NameText, BaseURI, Out, Indent, Options) :- 2990 !, 2991 format(Out, '~N~*|<', [Indent]), 2992 rdf_write_id(Out, NameText), 2993 option(encoding(Encoding), Options, utf8), 2994 rdf_value(Type, BaseURI, QVal, Encoding), 2995 format(Out, ' rdf:datatype="~w">', [QVal]), 2996 save_attribute_value(Value, Out, Options), 2997 write(Out, '</'), rdf_write_id(Out, NameText), write(Out, '>'). 2998save_body_literal(Literal, 2999 NameText, _, Out, Indent, Options) :- 3000 atomic(Literal), 3001 !, 3002 format(Out, '~N~*|<', [Indent]), 3003 rdf_write_id(Out, NameText), 3004 write(Out, '>'), 3005 save_attribute_value(Literal, Out, Options), 3006 write(Out, '</'), rdf_write_id(Out, NameText), write(Out, '>'). 3007save_body_literal(DOM, 3008 NameText, BaseURI, Out, Indent, Options) :- 3009 rdf_equal(Type, rdf:'XMLLiteral'), 3010 save_body_literal(type(Type, DOM), 3011 NameText, BaseURI, Out, Indent, Options). 3012 3013save_attribute_value(Value, Out, Options) :- % strings 3014 ( atom(Value) 3015 ; string(Value) 3016 ), 3017 !, 3018 option(encoding(Encoding), Options, utf8), 3019 xml_quote_cdata(Value, QVal, Encoding), 3020 write(Out, QVal). 3021save_attribute_value(Value, Out, _Options) :- % numbers 3022 number(Value), 3023 !, 3024 writeq(Out, Value). % quoted: preserve floats 3025save_attribute_value(Value, _Out, _Options) :- 3026 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.
3040save_xml_literal(DOM, Attr, Out, Indent, Options) :- 3041 xml_is_dom(DOM), 3042 !, 3043 memberchk(nsmap(NsMap), Options), 3044 id_to_atom(Attr, Atom), 3045 xml_write(Out, 3046 element(Atom, ['rdf:parseType'='Literal'], DOM), 3047 [ header(false), 3048 indent(Indent), 3049 nsmap(NsMap) 3050 ]). 3051save_xml_literal(NoDOM, _, _, _, _) :- 3052 must_be(xml_dom, NoDOM). 3053 3054id_to_atom(NS:Local, Atom) :- 3055 !, 3056 atomic_list_concat([NS,Local], :, Atom). 3057id_to_atom(ID, ID).
3067:- rdf_meta 3068 rdf_collection(r), 3069 collection_p(r,r). 3070 3071rdf_collection(rdf:nil) :- !. 3072rdf_collection(Cell) :- 3073 rdf_is_bnode(Cell), 3074 findall(F, rdf(Cell, rdf:first, F), [_]), 3075 findall(F, rdf(Cell, rdf:rest, F), [Rest]), 3076 forall(rdf(Cell, P, V), 3077 collection_p(P, V)), 3078 rdf_collection(Rest). 3079 3080collection_p(rdf:first, V) :- atom(V). 3081collection_p(rdf:rest, _). 3082collection_p(rdf:type, rdf:'List').
3087rdf_save_list(_, List, _, _, _) :- 3088 rdf_equal(List, rdf:nil), 3089 !. 3090rdf_save_list(Out, List, BaseURI, Indent, Options) :- 3091 rdf_has(List, rdf:first, First), 3092 ( rdf_is_bnode(First) 3093 -> nl(Out), 3094 rdf_save_subject(Out, First, BaseURI, Indent, Options) 3095 ; option(encoding(Encoding), Options, utf8), 3096 rdf_value(First, BaseURI, QVal, Encoding), 3097 format(Out, '~N~*|<rdf:Description rdf:about="~w"/>', 3098 [Indent, QVal]) 3099 ), 3100 flag(rdf_db_saved_triples, X, X+3), 3101 ( rdf_has(List, rdf:rest, List2), 3102 \+ rdf_equal(List2, rdf:nil) 3103 -> rdf_save_list(Out, List2, BaseURI, Indent, Options) 3104 ; true 3105 ).
3113rdf_id(Id, BaseURI, Local) :- 3114 assertion(atom(BaseURI)), 3115 atom_concat(BaseURI, Local, Id), 3116 sub_atom(Local, 0, 1, _, #), 3117 !. 3118rdf_id(Id, _, NS:Local) :- 3119 iri_xml_namespace(Id, Full, Local), 3120 ns(NS, Full), 3121 !. 3122rdf_id(Id, _, NS:Local) :- 3123 ns(NS, Full), 3124 Full \== '', 3125 atom_concat(Full, Local, Id), 3126 !. 3127rdf_id(Id, _, Id).
3135rdf_write_id(Out, NS:Local) :- 3136 !, 3137 format(Out, '~w:~w', [NS, Local]). 3138rdf_write_id(Out, Atom) :- 3139 write(Out, Atom).
3148rdf_value(Base, Base, '', _) :- !. 3149rdf_value(V, Base, Text, Encoding) :- 3150 atom_concat(Base, Local, V), 3151 sub_atom(Local, 0, _, _, #), 3152 !, 3153 xml_quote_attribute(Local, Text, Encoding). 3154rdf_value(V, _, Text, Encoding) :- 3155 ns(NS, Full), 3156 atom_concat(Full, Local, V), 3157 xml_is_name(Local), 3158 !, 3159 xml_quote_attribute(Local, QLocal, Encoding), 3160 atomic_list_concat(['&', NS, (';'), QLocal], Text). 3161rdf_value(V, _, Q, Encoding) :- 3162 xml_quote_attribute(V, Q, Encoding). 3163 3164 3165 /******************************* 3166 * MATCH AND COMPARE * 3167 *******************************/
icase, substring, word, prefix or like. For backward
compatibility, exact is a synonym for icase.3190 /******************************* 3191 * DEPRECATED MATERIAL * 3192 *******************************/
3202rdf_split_url(Prefix, Local, URL) :- 3203 atomic(URL), 3204 !, 3205 iri_xml_namespace(URL, Prefix, Local). 3206rdf_split_url(Prefix, Local, URL) :- 3207 atom_concat(Prefix, Local, URL).
3215rdf_url_namespace(URL, Prefix) :- 3216 iri_xml_namespace(URL, Prefix). 3217 3218 3219 /******************************* 3220 * LITERALS * 3221 *******************************/
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).3309 /******************************* 3310 * MISC * 3311 *******************************/
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.
3408 /******************************* 3409 * MESSAGES * 3410 *******************************/ 3411 3412:- multifile 3413 prolog:message//1. 3414 3415prologmessage(rdf(Term)) --> 3416 message(Term). 3417 3418message(loaded(How, What, BaseURI, Triples, Time)) --> 3419 how(How), 3420 source(What), 3421 into(What, BaseURI), 3422 in_time(Triples, Time). 3423message(save_removed_duplicates(N, Subject)) --> 3424 [ 'Removed ~d duplicate triples about "~p"'-[N,Subject] ]. 3425message(saved(File, SavedSubjects, SavedTriples)) --> 3426 [ 'Saved ~D triples about ~D subjects into ~p'- 3427 [SavedTriples, SavedSubjects, File] 3428 ]. 3429message(using_namespace(Id, NS)) --> 3430 [ 'Using namespace id ~w for ~w'-[Id, NS] ]. 3431message(inconsistent_cache(DB, Graphs)) --> 3432 [ 'RDF cache file for ~w contains the following graphs'-[DB], nl, 3433 '~t~8|~p'-[Graphs] 3434 ]. 3435message(guess_format(Ext)) --> 3436 [ 'Unknown file-extension: ~w. Assuming RDF/XML'-[Ext] ]. 3437message(meta(not_expanded(G))) --> 3438 [ 'rdf_meta/1: ~p is not expanded'-[G] ]. 3439message(deprecated(rdf_unload(Graph))) --> 3440 [ 'rdf_unload/1: Use ~q'-[rdf_unload_graph(Graph)] ]. 3441 3442 3443how(load) --> [ 'Loaded' ]. 3444how(parsed) --> [ 'Parsed' ]. 3445 3446source(SourceURL) --> 3447 { uri_file_name(SourceURL, File), 3448 !, 3449 file_base_name(File, Base) % TBD: relative file? 3450 }, 3451 [ ' "~w"'-[Base] ]. 3452source(SourceURL) --> 3453 [ ' "~w"'-[SourceURL] ]. 3454 3455into(_, _) --> []. % TBD 3456 3457in_time(Triples, ParseTime) --> 3458 [ ' in ~2f sec; ~D triples'-[ParseTime, Triples] 3459 ]
Core RDF database
The file library(semweb/rdf_db) provides the core of the SWI-Prolog RDF store.