… | |
… | |
64 | so, and even documents what "correct" means. |
64 | so, and even documents what "correct" means. |
65 | |
65 | |
66 | =item * round-trip integrity |
66 | =item * round-trip integrity |
67 | |
67 | |
68 | When you serialise a perl data structure using only data types supported |
68 | When you serialise a perl data structure using only data types supported |
69 | by JSON, the deserialised data structure is identical on the Perl level. |
69 | by JSON and Perl, the deserialised data structure is identical on the Perl |
70 | (e.g. the string "2.0" doesn't suddenly become "2" just because it looks |
70 | level. (e.g. the string "2.0" doesn't suddenly become "2" just because |
71 | like a number). There minor I<are> exceptions to this, read the MAPPING |
71 | it looks like a number). There I<are> minor exceptions to this, read the |
72 | section below to learn about those. |
72 | MAPPING section below to learn about those. |
73 | |
73 | |
74 | =item * strict checking of JSON correctness |
74 | =item * strict checking of JSON correctness |
75 | |
75 | |
76 | There is no guessing, no generating of illegal JSON texts by default, |
76 | There is no guessing, no generating of illegal JSON texts by default, |
77 | and only JSON is accepted as input by default (the latter is a security |
77 | and only JSON is accepted as input by default (the latter is a security |
… | |
… | |
83 | this module usually compares favourably in terms of speed, too. |
83 | this module usually compares favourably in terms of speed, too. |
84 | |
84 | |
85 | =item * simple to use |
85 | =item * simple to use |
86 | |
86 | |
87 | This module has both a simple functional interface as well as an object |
87 | This module has both a simple functional interface as well as an object |
88 | oriented interface interface. |
88 | oriented interface. |
89 | |
89 | |
90 | =item * reasonably versatile output formats |
90 | =item * reasonably versatile output formats |
91 | |
91 | |
92 | You can choose between the most compact guaranteed-single-line format |
92 | You can choose between the most compact guaranteed-single-line format |
93 | possible (nice for simple line-based protocols), a pure-ASCII format |
93 | possible (nice for simple line-based protocols), a pure-ASCII format |
… | |
… | |
99 | |
99 | |
100 | =cut |
100 | =cut |
101 | |
101 | |
102 | package JSON::XS; |
102 | package JSON::XS; |
103 | |
103 | |
104 | no warnings; |
104 | use common::sense; |
105 | use strict; |
|
|
106 | |
105 | |
107 | our $VERSION = '2.232'; |
106 | our $VERSION = 2.34; |
108 | our @ISA = qw(Exporter); |
107 | our @ISA = qw(Exporter); |
109 | |
108 | |
110 | our @EXPORT = qw(encode_json decode_json to_json from_json); |
109 | our @EXPORT = qw(encode_json decode_json); |
111 | |
|
|
112 | sub to_json($) { |
|
|
113 | require Carp; |
|
|
114 | Carp::croak ("JSON::XS::to_json has been renamed to encode_json, either downgrade to pre-2.0 versions of JSON::XS or rename the call"); |
|
|
115 | } |
|
|
116 | |
|
|
117 | sub from_json($) { |
|
|
118 | require Carp; |
|
|
119 | Carp::croak ("JSON::XS::from_json has been renamed to decode_json, either downgrade to pre-2.0 versions of JSON::XS or rename the call"); |
|
|
120 | } |
|
|
121 | |
110 | |
122 | use Exporter; |
111 | use Exporter; |
123 | use XSLoader; |
112 | use XSLoader; |
124 | |
113 | |
125 | =head1 FUNCTIONAL INTERFACE |
114 | =head1 FUNCTIONAL INTERFACE |
… | |
… | |
433 | If C<$enable> is true (or missing), then the C<encode> method will output JSON objects |
422 | If C<$enable> is true (or missing), then the C<encode> method will output JSON objects |
434 | by sorting their keys. This is adding a comparatively high overhead. |
423 | by sorting their keys. This is adding a comparatively high overhead. |
435 | |
424 | |
436 | If C<$enable> is false, then the C<encode> method will output key-value |
425 | If C<$enable> is false, then the C<encode> method will output key-value |
437 | pairs in the order Perl stores them (which will likely change between runs |
426 | pairs in the order Perl stores them (which will likely change between runs |
438 | of the same script). |
427 | of the same script, and can change even within the same run from 5.18 |
|
|
428 | onwards). |
439 | |
429 | |
440 | This option is useful if you want the same data structure to be encoded as |
430 | This option is useful if you want the same data structure to be encoded as |
441 | the same JSON text (given the same overall settings). If it is disabled, |
431 | the same JSON text (given the same overall settings). If it is disabled, |
442 | the same hash might be encoded differently even if contains the same data, |
432 | the same hash might be encoded differently even if contains the same data, |
443 | as key-value pairs have no inherent ordering in Perl. |
433 | as key-value pairs have no inherent ordering in Perl. |
444 | |
434 | |
445 | This setting has no effect when decoding JSON texts. |
435 | This setting has no effect when decoding JSON texts. |
|
|
436 | |
|
|
437 | This setting has currently no effect on tied hashes. |
446 | |
438 | |
447 | =item $json = $json->allow_nonref ([$enable]) |
439 | =item $json = $json->allow_nonref ([$enable]) |
448 | |
440 | |
449 | =item $enabled = $json->get_allow_nonref |
441 | =item $enabled = $json->get_allow_nonref |
450 | |
442 | |
… | |
… | |
665 | |
657 | |
666 | See SECURITY CONSIDERATIONS, below, for more info on why this is useful. |
658 | See SECURITY CONSIDERATIONS, below, for more info on why this is useful. |
667 | |
659 | |
668 | =item $json_text = $json->encode ($perl_scalar) |
660 | =item $json_text = $json->encode ($perl_scalar) |
669 | |
661 | |
670 | Converts the given Perl data structure (a simple scalar or a reference |
662 | Converts the given Perl value or data structure to its JSON |
671 | to a hash or array) to its JSON representation. Simple scalars will be |
663 | representation. Croaks on error. |
672 | converted into JSON string or number sequences, while references to arrays |
|
|
673 | become JSON arrays and references to hashes become JSON objects. Undefined |
|
|
674 | Perl values (e.g. C<undef>) become JSON C<null> values. Neither C<true> |
|
|
675 | nor C<false> values will be generated. |
|
|
676 | |
664 | |
677 | =item $perl_scalar = $json->decode ($json_text) |
665 | =item $perl_scalar = $json->decode ($json_text) |
678 | |
666 | |
679 | The opposite of C<encode>: expects a JSON text and tries to parse it, |
667 | The opposite of C<encode>: expects a JSON text and tries to parse it, |
680 | returning the resulting simple scalar or reference. Croaks on error. |
668 | returning the resulting simple scalar or reference. Croaks on error. |
681 | |
|
|
682 | JSON numbers and strings become simple Perl scalars. JSON arrays become |
|
|
683 | Perl arrayrefs and JSON objects become Perl hashrefs. C<true> becomes |
|
|
684 | C<1>, C<false> becomes C<0> and C<null> becomes C<undef>. |
|
|
685 | |
669 | |
686 | =item ($perl_scalar, $characters) = $json->decode_prefix ($json_text) |
670 | =item ($perl_scalar, $characters) = $json->decode_prefix ($json_text) |
687 | |
671 | |
688 | This works like the C<decode> method, but instead of raising an exception |
672 | This works like the C<decode> method, but instead of raising an exception |
689 | when there is trailing garbage after the first JSON object, it will |
673 | when there is trailing garbage after the first JSON object, it will |
… | |
… | |
712 | calls). |
696 | calls). |
713 | |
697 | |
714 | JSON::XS will only attempt to parse the JSON text once it is sure it |
698 | JSON::XS will only attempt to parse the JSON text once it is sure it |
715 | has enough text to get a decisive result, using a very simple but |
699 | has enough text to get a decisive result, using a very simple but |
716 | truly incremental parser. This means that it sometimes won't stop as |
700 | truly incremental parser. This means that it sometimes won't stop as |
717 | early as the full parser, for example, it doesn't detect parenthese |
701 | early as the full parser, for example, it doesn't detect mismatched |
718 | mismatches. The only thing it guarantees is that it starts decoding as |
702 | parentheses. The only thing it guarantees is that it starts decoding as |
719 | soon as a syntactically valid JSON text has been seen. This means you need |
703 | soon as a syntactically valid JSON text has been seen. This means you need |
720 | to set resource limits (e.g. C<max_size>) to ensure the parser will stop |
704 | to set resource limits (e.g. C<max_size>) to ensure the parser will stop |
721 | parsing in the presence if syntax errors. |
705 | parsing in the presence if syntax errors. |
722 | |
706 | |
723 | The following methods implement this incremental parser. |
707 | The following methods implement this incremental parser. |
… | |
… | |
739 | |
723 | |
740 | If the method is called in scalar context, then it will try to extract |
724 | If the method is called in scalar context, then it will try to extract |
741 | exactly I<one> JSON object. If that is successful, it will return this |
725 | exactly I<one> JSON object. If that is successful, it will return this |
742 | object, otherwise it will return C<undef>. If there is a parse error, |
726 | object, otherwise it will return C<undef>. If there is a parse error, |
743 | this method will croak just as C<decode> would do (one can then use |
727 | this method will croak just as C<decode> would do (one can then use |
744 | C<incr_skip> to skip the errornous part). This is the most common way of |
728 | C<incr_skip> to skip the erroneous part). This is the most common way of |
745 | using the method. |
729 | using the method. |
746 | |
730 | |
747 | And finally, in list context, it will try to extract as many objects |
731 | And finally, in list context, it will try to extract as many objects |
748 | from the stream as it can find and return them, or the empty list |
732 | from the stream as it can find and return them, or the empty list |
749 | otherwise. For this to work, there must be no separators between the JSON |
733 | otherwise. For this to work, there must be no separators between the JSON |
750 | objects or arrays, instead they must be concatenated back-to-back. If |
734 | objects or arrays, instead they must be concatenated back-to-back. If |
751 | an error occurs, an exception will be raised as in the scalar context |
735 | an error occurs, an exception will be raised as in the scalar context |
752 | case. Note that in this case, any previously-parsed JSON texts will be |
736 | case. Note that in this case, any previously-parsed JSON texts will be |
753 | lost. |
737 | lost. |
754 | |
738 | |
|
|
739 | Example: Parse some JSON arrays/objects in a given string and return |
|
|
740 | them. |
|
|
741 | |
|
|
742 | my @objs = JSON::XS->new->incr_parse ("[5][7][1,2]"); |
|
|
743 | |
755 | =item $lvalue_string = $json->incr_text |
744 | =item $lvalue_string = $json->incr_text |
756 | |
745 | |
757 | This method returns the currently stored JSON fragment as an lvalue, that |
746 | This method returns the currently stored JSON fragment as an lvalue, that |
758 | is, you can manipulate it. This I<only> works when a preceding call to |
747 | is, you can manipulate it. This I<only> works when a preceding call to |
759 | C<incr_parse> in I<scalar context> successfully returned an object. Under |
748 | C<incr_parse> in I<scalar context> successfully returned an object. Under |
… | |
… | |
773 | C<incr_parse> died, in which case the input buffer and incremental parser |
762 | C<incr_parse> died, in which case the input buffer and incremental parser |
774 | state is left unchanged, to skip the text parsed so far and to reset the |
763 | state is left unchanged, to skip the text parsed so far and to reset the |
775 | parse state. |
764 | parse state. |
776 | |
765 | |
777 | The difference to C<incr_reset> is that only text until the parse error |
766 | The difference to C<incr_reset> is that only text until the parse error |
778 | occured is removed. |
767 | occurred is removed. |
779 | |
768 | |
780 | =item $json->incr_reset |
769 | =item $json->incr_reset |
781 | |
770 | |
782 | This completely resets the incremental parser, that is, after this call, |
771 | This completely resets the incremental parser, that is, after this call, |
783 | it will be as if the parser had never parsed anything. |
772 | it will be as if the parser had never parsed anything. |
… | |
… | |
981 | If the number consists of digits only, JSON::XS will try to represent |
970 | If the number consists of digits only, JSON::XS will try to represent |
982 | it as an integer value. If that fails, it will try to represent it as |
971 | it as an integer value. If that fails, it will try to represent it as |
983 | a numeric (floating point) value if that is possible without loss of |
972 | a numeric (floating point) value if that is possible without loss of |
984 | precision. Otherwise it will preserve the number as a string value (in |
973 | precision. Otherwise it will preserve the number as a string value (in |
985 | which case you lose roundtripping ability, as the JSON number will be |
974 | which case you lose roundtripping ability, as the JSON number will be |
986 | re-encoded toa JSON string). |
975 | re-encoded to a JSON string). |
987 | |
976 | |
988 | Numbers containing a fractional or exponential part will always be |
977 | Numbers containing a fractional or exponential part will always be |
989 | represented as numeric (floating point) values, possibly at a loss of |
978 | represented as numeric (floating point) values, possibly at a loss of |
990 | precision (in which case you might lose perfect roundtripping ability, but |
979 | precision (in which case you might lose perfect roundtripping ability, but |
991 | the JSON number will still be re-encoded as a JSON number). |
980 | the JSON number will still be re-encoded as a JSON number). |
|
|
981 | |
|
|
982 | Note that precision is not accuracy - binary floating point values cannot |
|
|
983 | represent most decimal fractions exactly, and when converting from and to |
|
|
984 | floating point, JSON::XS only guarantees precision up to but not including |
|
|
985 | the least significant bit. |
992 | |
986 | |
993 | =item true, false |
987 | =item true, false |
994 | |
988 | |
995 | These JSON atoms become C<JSON::XS::true> and C<JSON::XS::false>, |
989 | These JSON atoms become C<JSON::XS::true> and C<JSON::XS::false>, |
996 | respectively. They are overloaded to act almost exactly like the numbers |
990 | respectively. They are overloaded to act almost exactly like the numbers |
… | |
… | |
1084 | |
1078 | |
1085 | You can not currently force the type in other, less obscure, ways. Tell me |
1079 | You can not currently force the type in other, less obscure, ways. Tell me |
1086 | if you need this capability (but don't forget to explain why it's needed |
1080 | if you need this capability (but don't forget to explain why it's needed |
1087 | :). |
1081 | :). |
1088 | |
1082 | |
|
|
1083 | Note that numerical precision has the same meaning as under Perl (so |
|
|
1084 | binary to decimal conversion follows the same rules as in Perl, which |
|
|
1085 | can differ to other languages). Also, your perl interpreter might expose |
|
|
1086 | extensions to the floating point numbers of your platform, such as |
|
|
1087 | infinities or NaN's - these cannot be represented in JSON, and it is an |
|
|
1088 | error to pass those in. |
|
|
1089 | |
1089 | =back |
1090 | =back |
1090 | |
1091 | |
1091 | |
1092 | |
1092 | =head1 ENCODING/CODESET FLAG NOTES |
1093 | =head1 ENCODING/CODESET FLAG NOTES |
1093 | |
1094 | |
… | |
… | |
1119 | =item C<utf8> flag disabled |
1120 | =item C<utf8> flag disabled |
1120 | |
1121 | |
1121 | When C<utf8> is disabled (the default), then C<encode>/C<decode> generate |
1122 | When C<utf8> is disabled (the default), then C<encode>/C<decode> generate |
1122 | and expect Unicode strings, that is, characters with high ordinal Unicode |
1123 | and expect Unicode strings, that is, characters with high ordinal Unicode |
1123 | values (> 255) will be encoded as such characters, and likewise such |
1124 | values (> 255) will be encoded as such characters, and likewise such |
1124 | characters are decoded as-is, no canges to them will be done, except |
1125 | characters are decoded as-is, no changes to them will be done, except |
1125 | "(re-)interpreting" them as Unicode codepoints or Unicode characters, |
1126 | "(re-)interpreting" them as Unicode codepoints or Unicode characters, |
1126 | respectively (to Perl, these are the same thing in strings unless you do |
1127 | respectively (to Perl, these are the same thing in strings unless you do |
1127 | funny/weird/dumb stuff). |
1128 | funny/weird/dumb stuff). |
1128 | |
1129 | |
1129 | This is useful when you want to do the encoding yourself (e.g. when you |
1130 | This is useful when you want to do the encoding yourself (e.g. when you |
… | |
… | |
1209 | use JSON::XS; |
1210 | use JSON::XS; |
1210 | |
1211 | |
1211 | print encode_json [chr 0x2028]; |
1212 | print encode_json [chr 0x2028]; |
1212 | |
1213 | |
1213 | The right fix for this is to use a proper JSON parser in your javascript |
1214 | The right fix for this is to use a proper JSON parser in your javascript |
1214 | programs, and not rely on C<eval>. |
1215 | programs, and not rely on C<eval> (see for example Douglas Crockford's |
|
|
1216 | F<json2.js> parser). |
1215 | |
1217 | |
1216 | If this is not an option, you can, as a stop-gap measure, simply encode to |
1218 | If this is not an option, you can, as a stop-gap measure, simply encode to |
1217 | ASCII-only JSON: |
1219 | ASCII-only JSON: |
1218 | |
1220 | |
1219 | use JSON::XS; |
1221 | use JSON::XS; |
1220 | |
1222 | |
1221 | print JSON::XS->new->ascii->encode ([chr 0x2028]); |
1223 | print JSON::XS->new->ascii->encode ([chr 0x2028]); |
1222 | |
1224 | |
1223 | And if you are concerned about the size of the resulting JSON text, you |
1225 | Note that this will enlarge the resulting JSON text quite a bit if you |
1224 | can run some regexes to only escape U+2028 and U+2029: |
1226 | have many non-ASCII characters. You might be tempted to run some regexes |
|
|
1227 | to only escape U+2028 and U+2029, e.g.: |
1225 | |
1228 | |
1226 | use JSON::XS; |
1229 | # DO NOT USE THIS! |
1227 | |
|
|
1228 | my $json = JSON::XS->new->utf8->encode ([chr 0x2028]); |
1230 | my $json = JSON::XS->new->utf8->encode ([chr 0x2028]); |
1229 | $json =~ s/\xe2\x80\xa8/\\u2028/g; # escape U+2028 |
1231 | $json =~ s/\xe2\x80\xa8/\\u2028/g; # escape U+2028 |
1230 | $json =~ s/\xe2\x80\xa9/\\u2029/g; # escape U+2029 |
1232 | $json =~ s/\xe2\x80\xa9/\\u2029/g; # escape U+2029 |
1231 | print $json; |
1233 | print $json; |
1232 | |
1234 | |
1233 | This works because U+2028/U+2029 are not allowed outside of strings and |
1235 | Note that I<this is a bad idea>: the above only works for U+2028 and |
1234 | are not used for syntax, so replacing them unconditionally just works. |
|
|
1235 | |
|
|
1236 | Note, however, that fixing the broken JSON parser is better than working |
|
|
1237 | around it in every other generator. The above regexes should work well in |
|
|
1238 | other languages, as long as they operate on UTF-8. It is equally valid to |
|
|
1239 | replace all occurences of U+2028/2029 directly by their \\u-escaped forms |
|
|
1240 | in unicode texts, so they can simply be used to fix any parsers relying on |
|
|
1241 | C<eval> by first applying the regexes on the encoded texts. |
|
|
1242 | |
|
|
1243 | Note also that the above only works for U+2028 and U+2029 and thus |
|
|
1244 | only for fully ECMAscript-compliant parsers. Many existing javascript |
1236 | U+2029 and thus only for fully ECMAscript-compliant parsers. Many existing |
1245 | implementations misparse other characters as well. Best rely on a good |
1237 | javascript implementations, however, have issues with other characters as |
1246 | JSON parser, such as Douglas Crockfords F<json2.js>, which escapes the |
1238 | well - using C<eval> naively simply I<will> cause problems. |
1247 | above and many more problematic characters properly before passing them |
|
|
1248 | into C<eval>. |
|
|
1249 | |
1239 | |
1250 | Another problem is that some javascript implementations reserve |
1240 | Another problem is that some javascript implementations reserve |
1251 | some property names for their own purposes (which probably makes |
1241 | some property names for their own purposes (which probably makes |
1252 | them non-ECMAscript-compliant). For example, Iceweasel reserves the |
1242 | them non-ECMAscript-compliant). For example, Iceweasel reserves the |
1253 | C<__proto__> property name for it's own purposes. |
1243 | C<__proto__> property name for its own purposes. |
1254 | |
1244 | |
1255 | If that is a problem, you could parse try to filter the resulting JSON |
1245 | If that is a problem, you could parse try to filter the resulting JSON |
1256 | output for these property strings, e.g.: |
1246 | output for these property strings, e.g.: |
1257 | |
1247 | |
1258 | $json =~ s/"__proto__"\s*:/"__proto__renamed":/g; |
1248 | $json =~ s/"__proto__"\s*:/"__proto__renamed":/g; |
1259 | |
1249 | |
1260 | This works because C<__proto__> is not valid outside of strings, so every |
1250 | This works because C<__proto__> is not valid outside of strings, so every |
1261 | occurence of C<"__proto__"\s*:> must be a string used as property name. |
1251 | occurrence of C<"__proto__"\s*:> must be a string used as property name. |
1262 | |
1252 | |
1263 | If you know of other incompatibilities, please let me know. |
1253 | If you know of other incompatibilities, please let me know. |
1264 | |
1254 | |
1265 | |
1255 | |
1266 | =head2 JSON and YAML |
1256 | =head2 JSON and YAML |
… | |
… | |
1278 | my $yaml = $to_yaml->encode ($ref) . "\n"; |
1268 | my $yaml = $to_yaml->encode ($ref) . "\n"; |
1279 | |
1269 | |
1280 | This will I<usually> generate JSON texts that also parse as valid |
1270 | This will I<usually> generate JSON texts that also parse as valid |
1281 | YAML. Please note that YAML has hardcoded limits on (simple) object key |
1271 | YAML. Please note that YAML has hardcoded limits on (simple) object key |
1282 | lengths that JSON doesn't have and also has different and incompatible |
1272 | lengths that JSON doesn't have and also has different and incompatible |
1283 | unicode handling, so you should make sure that your hash keys are |
1273 | unicode character escape syntax, so you should make sure that your hash |
1284 | noticeably shorter than the 1024 "stream characters" YAML allows and that |
1274 | keys are noticeably shorter than the 1024 "stream characters" YAML allows |
1285 | you do not have characters with codepoint values outside the Unicode BMP |
1275 | and that you do not have characters with codepoint values outside the |
1286 | (basic multilingual page). YAML also does not allow C<\/> sequences in |
1276 | Unicode BMP (basic multilingual page). YAML also does not allow C<\/> |
1287 | strings (which JSON::XS does not I<currently> generate, but other JSON |
1277 | sequences in strings (which JSON::XS does not I<currently> generate, but |
1288 | generators might). |
1278 | other JSON generators might). |
1289 | |
1279 | |
1290 | There might be other incompatibilities that I am not aware of (or the YAML |
1280 | There might be other incompatibilities that I am not aware of (or the YAML |
1291 | specification has been changed yet again - it does so quite often). In |
1281 | specification has been changed yet again - it does so quite often). In |
1292 | general you should not try to generate YAML with a JSON generator or vice |
1282 | general you should not try to generate YAML with a JSON generator or vice |
1293 | versa, or try to parse JSON with a YAML parser or vice versa: chances are |
1283 | versa, or try to parse JSON with a YAML parser or vice versa: chances are |
… | |
… | |
1312 | that difficult or long) and finally make YAML compatible to it, and |
1302 | that difficult or long) and finally make YAML compatible to it, and |
1313 | educating users about the changes, instead of spreading lies about the |
1303 | educating users about the changes, instead of spreading lies about the |
1314 | real compatibility for many I<years> and trying to silence people who |
1304 | real compatibility for many I<years> and trying to silence people who |
1315 | point out that it isn't true. |
1305 | point out that it isn't true. |
1316 | |
1306 | |
|
|
1307 | Addendum/2009: the YAML 1.2 spec is still incompatible with JSON, even |
|
|
1308 | though the incompatibilities have been documented (and are known to Brian) |
|
|
1309 | for many years and the spec makes explicit claims that YAML is a superset |
|
|
1310 | of JSON. It would be so easy to fix, but apparently, bullying people and |
|
|
1311 | corrupting userdata is so much easier. |
|
|
1312 | |
1317 | =back |
1313 | =back |
1318 | |
1314 | |
1319 | |
1315 | |
1320 | =head2 SPEED |
1316 | =head2 SPEED |
1321 | |
1317 | |
… | |
… | |
1328 | a very short single-line JSON string (also available at |
1324 | a very short single-line JSON string (also available at |
1329 | L<http://dist.schmorp.de/misc/json/short.json>). |
1325 | L<http://dist.schmorp.de/misc/json/short.json>). |
1330 | |
1326 | |
1331 | {"method": "handleMessage", "params": ["user1", |
1327 | {"method": "handleMessage", "params": ["user1", |
1332 | "we were just talking"], "id": null, "array":[1,11,234,-5,1e5,1e7, |
1328 | "we were just talking"], "id": null, "array":[1,11,234,-5,1e5,1e7, |
1333 | true, false]} |
1329 | 1, 0]} |
1334 | |
1330 | |
1335 | It shows the number of encodes/decodes per second (JSON::XS uses |
1331 | It shows the number of encodes/decodes per second (JSON::XS uses |
1336 | the functional interface, while JSON::XS/2 uses the OO interface |
1332 | the functional interface, while JSON::XS/2 uses the OO interface |
1337 | with pretty-printing and hashkey sorting enabled, JSON::XS/3 enables |
1333 | with pretty-printing and hashkey sorting enabled, JSON::XS/3 enables |
1338 | shrink). Higher is better: |
1334 | shrink. JSON::DWIW/DS uses the deserialise function, while JSON::DWIW::FJ |
|
|
1335 | uses the from_json method). Higher is better: |
1339 | |
1336 | |
1340 | module | encode | decode | |
1337 | module | encode | decode | |
1341 | -----------|------------|------------| |
1338 | --------------|------------|------------| |
1342 | JSON 1.x | 4990.842 | 4088.813 | |
1339 | JSON::DWIW/DS | 86302.551 | 102300.098 | |
1343 | JSON::DWIW | 51653.990 | 71575.154 | |
1340 | JSON::DWIW/FJ | 86302.551 | 75983.768 | |
1344 | JSON::PC | 65948.176 | 74631.744 | |
1341 | JSON::PP | 15827.562 | 6638.658 | |
1345 | JSON::PP | 8931.652 | 3817.168 | |
1342 | JSON::Syck | 63358.066 | 47662.545 | |
1346 | JSON::Syck | 24877.248 | 27776.848 | |
1343 | JSON::XS | 511500.488 | 511500.488 | |
1347 | JSON::XS | 388361.481 | 227951.304 | |
1344 | JSON::XS/2 | 291271.111 | 388361.481 | |
1348 | JSON::XS/2 | 227951.304 | 218453.333 | |
1345 | JSON::XS/3 | 361577.931 | 361577.931 | |
1349 | JSON::XS/3 | 338250.323 | 218453.333 | |
1346 | Storable | 66788.280 | 265462.278 | |
1350 | Storable | 16500.016 | 135300.129 | |
|
|
1351 | -----------+------------+------------+ |
1347 | --------------+------------+------------+ |
1352 | |
1348 | |
1353 | That is, JSON::XS is about five times faster than JSON::DWIW on encoding, |
1349 | That is, JSON::XS is almost six times faster than JSON::DWIW on encoding, |
1354 | about three times faster on decoding, and over forty times faster |
1350 | about five times faster on decoding, and over thirty to seventy times |
1355 | than JSON, even with pretty-printing and key sorting. It also compares |
1351 | faster than JSON's pure perl implementation. It also compares favourably |
1356 | favourably to Storable for small amounts of data. |
1352 | to Storable for small amounts of data. |
1357 | |
1353 | |
1358 | Using a longer test string (roughly 18KB, generated from Yahoo! Locals |
1354 | Using a longer test string (roughly 18KB, generated from Yahoo! Locals |
1359 | search API (L<http://dist.schmorp.de/misc/json/long.json>). |
1355 | search API (L<http://dist.schmorp.de/misc/json/long.json>). |
1360 | |
1356 | |
1361 | module | encode | decode | |
1357 | module | encode | decode | |
1362 | -----------|------------|------------| |
1358 | --------------|------------|------------| |
1363 | JSON 1.x | 55.260 | 34.971 | |
1359 | JSON::DWIW/DS | 1647.927 | 2673.916 | |
1364 | JSON::DWIW | 825.228 | 1082.513 | |
1360 | JSON::DWIW/FJ | 1630.249 | 2596.128 | |
1365 | JSON::PC | 3571.444 | 2394.829 | |
|
|
1366 | JSON::PP | 210.987 | 32.574 | |
1361 | JSON::PP | 400.640 | 62.311 | |
1367 | JSON::Syck | 552.551 | 787.544 | |
1362 | JSON::Syck | 1481.040 | 1524.869 | |
1368 | JSON::XS | 5780.463 | 4854.519 | |
1363 | JSON::XS | 20661.596 | 9541.183 | |
1369 | JSON::XS/2 | 3869.998 | 4798.975 | |
1364 | JSON::XS/2 | 10683.403 | 9416.938 | |
1370 | JSON::XS/3 | 5862.880 | 4798.975 | |
1365 | JSON::XS/3 | 20661.596 | 9400.054 | |
1371 | Storable | 4445.002 | 5235.027 | |
1366 | Storable | 19765.806 | 10000.725 | |
1372 | -----------+------------+------------+ |
1367 | --------------+------------+------------+ |
1373 | |
1368 | |
1374 | Again, JSON::XS leads by far (except for Storable which non-surprisingly |
1369 | Again, JSON::XS leads by far (except for Storable which non-surprisingly |
1375 | decodes faster). |
1370 | decodes a bit faster). |
1376 | |
1371 | |
1377 | On large strings containing lots of high Unicode characters, some modules |
1372 | On large strings containing lots of high Unicode characters, some modules |
1378 | (such as JSON::PC) seem to decode faster than JSON::XS, but the result |
1373 | (such as JSON::PC) seem to decode faster than JSON::XS, but the result |
1379 | will be broken due to missing (or wrong) Unicode handling. Others refuse |
1374 | will be broken due to missing (or wrong) Unicode handling. Others refuse |
1380 | to decode or encode properly, so it was impossible to prepare a fair |
1375 | to decode or encode properly, so it was impossible to prepare a fair |
… | |
… | |
1416 | information you might want to make sure that exceptions thrown by JSON::XS |
1411 | information you might want to make sure that exceptions thrown by JSON::XS |
1417 | will not end up in front of untrusted eyes. |
1412 | will not end up in front of untrusted eyes. |
1418 | |
1413 | |
1419 | If you are using JSON::XS to return packets to consumption |
1414 | If you are using JSON::XS to return packets to consumption |
1420 | by JavaScript scripts in a browser you should have a look at |
1415 | by JavaScript scripts in a browser you should have a look at |
1421 | L<http://jpsykes.com/47/practical-csrf-and-json-security> to see whether |
1416 | L<http://blog.archive.jpsykes.com/47/practical-csrf-and-json-security/> to |
1422 | you are vulnerable to some common attack vectors (which really are browser |
1417 | see whether you are vulnerable to some common attack vectors (which really |
1423 | design bugs, but it is still you who will have to deal with it, as major |
1418 | are browser design bugs, but it is still you who will have to deal with |
1424 | browser developers care only for features, not about getting security |
1419 | it, as major browser developers care only for features, not about getting |
1425 | right). |
1420 | security right). |
1426 | |
1421 | |
1427 | |
1422 | |
1428 | =head1 THREADS |
1423 | =head1 THREADS |
1429 | |
1424 | |
1430 | This module is I<not> guaranteed to be thread safe and there are no |
1425 | This module is I<not> guaranteed to be thread safe and there are no |
1431 | plans to change this until Perl gets thread support (as opposed to the |
1426 | plans to change this until Perl gets thread support (as opposed to the |
1432 | horribly slow so-called "threads" which are simply slow and bloated |
1427 | horribly slow so-called "threads" which are simply slow and bloated |
1433 | process simulations - use fork, it's I<much> faster, cheaper, better). |
1428 | process simulations - use fork, it's I<much> faster, cheaper, better). |
1434 | |
1429 | |
1435 | (It might actually work, but you have been warned). |
1430 | (It might actually work, but you have been warned). |
|
|
1431 | |
|
|
1432 | |
|
|
1433 | =head1 THE PERILS OF SETLOCALE |
|
|
1434 | |
|
|
1435 | Sometimes people avoid the Perl locale support and directly call the |
|
|
1436 | system's setlocale function with C<LC_ALL>. |
|
|
1437 | |
|
|
1438 | This breaks both perl and modules such as JSON::XS, as stringification of |
|
|
1439 | numbers no longer works correctly (e.g. C<$x = 0.1; print "$x"+1> might |
|
|
1440 | print C<1>, and JSON::XS might output illegal JSON as JSON::XS relies on |
|
|
1441 | perl to stringify numbers). |
|
|
1442 | |
|
|
1443 | The solution is simple: don't call C<setlocale>, or use it for only those |
|
|
1444 | categories you need, such as C<LC_MESSAGES> or C<LC_CTYPE>. |
|
|
1445 | |
|
|
1446 | If you need C<LC_NUMERIC>, you should enable it only around the code that |
|
|
1447 | actually needs it (avoiding stringification of numbers), and restore it |
|
|
1448 | afterwards. |
1436 | |
1449 | |
1437 | |
1450 | |
1438 | =head1 BUGS |
1451 | =head1 BUGS |
1439 | |
1452 | |
1440 | While the goal of this module is to be correct, that unfortunately does |
1453 | While the goal of this module is to be correct, that unfortunately does |