SQLite

Check-in [35ed68a6]
Login

Many hyperlinks are disabled.
Use anonymous login to enable hyperlinks.

Overview
Comment:Extend the json-path mechanism with array indexes of the form "#" or "#-n" for some positive number "n", to reference the end of an array.
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | json-path-enhancement
Files: files | file ages | folders
SHA3-256: 35ed68a651f4cf8740597433b0f1c3b345841868022e0904e9f342840ba0e502
User & Date: drh 2019-11-22 17:37:56
Context
2019-11-23
08:51
Enhance the path arguments in JSON functions to access "#-N" array indexes. (check-in: ffeec62c user: drh tags: trunk)
2019-11-22
17:37
Extend the json-path mechanism with array indexes of the form "#" or "#-n" for some positive number "n", to reference the end of an array. (Closed-Leaf check-in: 35ed68a6 user: drh tags: json-path-enhancement)
11:49
Fix a harmless compiler warning. (check-in: 34343c4b user: drh tags: trunk)
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to ext/misc/json1.c.

︙︙
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186


























1187
1188
1189
1190






1191
1192
1193
1194
1195
1196
1197

        pRoot = &pParse->aNode[iRoot];
        pRoot->u.iAppend = iStart - iRoot;
        pRoot->jnFlags |= JNODE_APPEND;
        pParse->aNode[iLabel].jnFlags |= JNODE_RAW;
      }
      return pNode;
    }
  }else if( zPath[0]=='[' && safe_isdigit(zPath[1]) ){
    if( pRoot->eType!=JSON_ARRAY ) return 0;
    i = 0;
    j = 1;
    while( safe_isdigit(zPath[j]) ){
      i = i*10 + zPath[j] - '0';
      j++;
    }


























    if( zPath[j]!=']' ){
      *pzErr = zPath;
      return 0;
    }






    zPath += j + 1;
    j = 1;
    for(;;){
      while( j<=pRoot->n && (i>0 || (pRoot[j].jnFlags & JNODE_REMOVE)!=0) ){
        if( (pRoot[j].jnFlags & JNODE_REMOVE)==0 ) i--;
        j += jsonNodeSize(&pRoot[j]);
      }








|
<






>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
|
|
|
|
>
>
>
>
>
>








1172
1173
1174
1175
1176
1177
1178
1179

1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228

        pRoot = &pParse->aNode[iRoot];
        pRoot->u.iAppend = iStart - iRoot;
        pRoot->jnFlags |= JNODE_APPEND;
        pParse->aNode[iLabel].jnFlags |= JNODE_RAW;
      }
      return pNode;
    }
  }else if( zPath[0]=='[' ){

    i = 0;
    j = 1;
    while( safe_isdigit(zPath[j]) ){
      i = i*10 + zPath[j] - '0';
      j++;
    }
    if( j<2 || zPath[j]!=']' ){
      if( zPath[1]=='#' ){
        JsonNode *pBase = pRoot;
        int iBase = iRoot;
        if( pRoot->eType!=JSON_ARRAY ) return 0;
        for(;;){
          while( j<=pBase->n ){
            if( (pBase[j].jnFlags & JNODE_REMOVE)==0 ) i++;
            j += jsonNodeSize(&pBase[j]);
          }
          if( (pBase->jnFlags & JNODE_APPEND)==0 ) break;
          iBase += pBase->u.iAppend;
          pBase = &pParse->aNode[iBase];
          j = 1;
        }
        j = 2;
        if( zPath[2]=='-' && safe_isdigit(zPath[3]) ){
          unsigned int x = 0;
          j = 3;
          do{
            x = x*10 + zPath[j] - '0';
            j++;
          }while( safe_isdigit(zPath[j]) );
          if( x>i ) return 0;
          i -= x;
        }
        if( zPath[j]!=']' ){
          *pzErr = zPath;
          return 0;
        }
      }else{
        *pzErr = zPath;
        return 0;
      }
    }
    if( pRoot->eType!=JSON_ARRAY ) return 0;
    zPath += j + 1;
    j = 1;
    for(;;){
      while( j<=pRoot->n && (i>0 || (pRoot[j].jnFlags & JNODE_REMOVE)!=0) ){
        if( (pRoot[j].jnFlags & JNODE_REMOVE)==0 ) i--;
        j += jsonNodeSize(&pRoot[j]);
      }
︙︙

Added test/json105.test. 















































































































































































































































>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118

# 2019-11-22
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements tests for "[#]" extension to json-path
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix json104

ifcapable !json1 {
  finish_test
  return
}

# This is the example from pages 2 and 3 of RFC-7396
db eval {
  CREATE TABLE t1(j);
  INSERT INTO t1(j) VALUES('{"a":1,"b":[1,[2,3],4],"c":99}');
}
proc json_extract_test {testnum path result} {
  do_execsql_test json105-1.$testnum "SELECT quote(json_extract(j,$path)) FROM t1" $result
}
json_extract_test 10 {'$.b[#]'}   NULL
json_extract_test 20 {'$.b[#-1]'} 4
json_extract_test 30 {'$.b[#-2]'} {'[2,3]'}
json_extract_test 31 {'$.b[#-02]'} {'[2,3]'}
json_extract_test 40 {'$.b[#-3]'} 1
json_extract_test 50 {'$.b[#-4]'} NULL
json_extract_test 60 {'$.b[#-2][#-1]'} 3
json_extract_test 70 {'$.b[0]','$.b[#-1]'} {'[1,4]'}

json_extract_test 100 {'$.a[#-1]'} NULL
json_extract_test 110 {'$.b[#-000001]'} 4

proc json_remove_test {testnum path result} {
  do_execsql_test json105-2.$testnum "SELECT quote(json_remove(j,$path)) FROM t1" $result
}
json_remove_test 10 {'$.b[#]'}    {'{"a":1,"b":[1,[2,3],4],"c":99}'}
json_remove_test 20 {'$.b[#-0]'}  {'{"a":1,"b":[1,[2,3],4],"c":99}'}
json_remove_test 30 {'$.b[#-1]'}  {'{"a":1,"b":[1,[2,3]],"c":99}'}
json_remove_test 40 {'$.b[#-2]'}  {'{"a":1,"b":[1,4],"c":99}'}
json_remove_test 50 {'$.b[#-3]'}  {'{"a":1,"b":[[2,3],4],"c":99}'}
json_remove_test 60 {'$.b[#-4]'}  {'{"a":1,"b":[1,[2,3],4],"c":99}'}
json_remove_test 70 {'$.b[#-2][#-1]'}  {'{"a":1,"b":[1,[2],4],"c":99}'}

json_remove_test 100 {'$.b[0]','$.b[#-1]'} {'{"a":1,"b":[[2,3]],"c":99}'}
json_remove_test 110 {'$.b[#-1]','$.b[0]'} {'{"a":1,"b":[[2,3]],"c":99}'}
json_remove_test 120 {'$.b[#-1]','$.b[#-2]'} {'{"a":1,"b":[[2,3]],"c":99}'}
json_remove_test 130 {'$.b[#-1]','$.b[#-1]'} {'{"a":1,"b":[1],"c":99}'}
json_remove_test 140 {'$.b[#-2]','$.b[#-1]'} {'{"a":1,"b":[1],"c":99}'}

proc json_insert_test {testnum x result} {
  do_execsql_test json105-3.$testnum "SELECT quote(json_insert(j,$x)) FROM t1" $result
}
json_insert_test 10 {'$.b[#]','AAA'} {'{"a":1,"b":[1,[2,3],4,"AAA"],"c":99}'}
json_insert_test 20 {'$.b[1][#]','AAA'} {'{"a":1,"b":[1,[2,3,"AAA"],4],"c":99}'}
json_insert_test 30 {'$.b[1][#]','AAA','$.b[#]','BBB'} \
     {'{"a":1,"b":[1,[2,3,"AAA"],4,"BBB"],"c":99}'}
json_insert_test 40 {'$.b[#]','AAA','$.b[#]','BBB'} \
     {'{"a":1,"b":[1,[2,3],4,"AAA","BBB"],"c":99}'}

proc json_set_test {testnum x result} {
  do_execsql_test json105-4.$testnum "SELECT quote(json_set(j,$x)) FROM t1" $result
}
json_set_test 10 {'$.b[#]','AAA'} {'{"a":1,"b":[1,[2,3],4,"AAA"],"c":99}'}
json_set_test 20 {'$.b[1][#]','AAA'} {'{"a":1,"b":[1,[2,3,"AAA"],4],"c":99}'}
json_set_test 30 {'$.b[1][#]','AAA','$.b[#]','BBB'} \
     {'{"a":1,"b":[1,[2,3,"AAA"],4,"BBB"],"c":99}'}
json_set_test 40 {'$.b[#]','AAA','$.b[#]','BBB'} \
     {'{"a":1,"b":[1,[2,3],4,"AAA","BBB"],"c":99}'}
json_set_test 50 {'$.b[#-1]','AAA'} {'{"a":1,"b":[1,[2,3],"AAA"],"c":99}'}
json_set_test 60 {'$.b[1][#-1]','AAA'} {'{"a":1,"b":[1,[2,"AAA"],4],"c":99}'}
json_set_test 70 {'$.b[1][#-1]','AAA','$.b[#-1]','BBB'} \
     {'{"a":1,"b":[1,[2,"AAA"],"BBB"],"c":99}'}
json_set_test 80 {'$.b[#-1]','AAA','$.b[#-1]','BBB'} \
     {'{"a":1,"b":[1,[2,3],"BBB"],"c":99}'}

proc json_replace_test {testnum x result} {
  do_execsql_test json105-5.$testnum "SELECT quote(json_replace(j,$x)) FROM t1" $result
}
json_replace_test 10 {'$.b[#]','AAA'} {'{"a":1,"b":[1,[2,3],4],"c":99}'}
json_replace_test 20 {'$.b[1][#]','AAA'} {'{"a":1,"b":[1,[2,3],4],"c":99}'}
json_replace_test 30 {'$.b[1][#]','AAA','$.b[#]','BBB'} \
     {'{"a":1,"b":[1,[2,3],4],"c":99}'}
json_replace_test 40 {'$.b[#]','AAA','$.b[#]','BBB'} \
     {'{"a":1,"b":[1,[2,3],4],"c":99}'}
json_replace_test 50 {'$.b[#-1]','AAA'} {'{"a":1,"b":[1,[2,3],"AAA"],"c":99}'}
json_replace_test 60 {'$.b[1][#-1]','AAA'} {'{"a":1,"b":[1,[2,"AAA"],4],"c":99}'}
json_replace_test 70 {'$.b[1][#-1]','AAA','$.b[#-1]','BBB'} \
     {'{"a":1,"b":[1,[2,"AAA"],"BBB"],"c":99}'}
json_replace_test 80 {'$.b[#-1]','AAA','$.b[#-1]','BBB'} \
     {'{"a":1,"b":[1,[2,3],"BBB"],"c":99}'}

do_catchsql_test json105-6.10 {
  SELECT json_extract(j, '$.b[#-]') FROM t1;
} {1 {JSON path error near '[#-]'}}
do_catchsql_test json105-6.20 {
  SELECT json_extract(j, '$.b[#9]') FROM t1;
} {1 {JSON path error near '[#9]'}}
do_catchsql_test json105-6.30 {
  SELECT json_extract(j, '$.b[#+2]') FROM t1;
} {1 {JSON path error near '[#+2]'}}
do_catchsql_test json105-6.40 {
  SELECT json_extract(j, '$.b[#-1') FROM t1;
} {1 {JSON path error near '[#-1'}}
do_catchsql_test json105-6.50 {
  SELECT json_extract(j, '$.b[#-1x]') FROM t1;
} {1 {JSON path error near '[#-1x]'}}

finish_test