sh/jshn.sh

   1 # functions for parsing and generating json
   2
   3 _json_get_var() {
   4         local ___dest="$1"
   5         local ___var="$2"
   6         eval "$___dest=\"\$${JSON_PREFIX}$___var\""
   7 }
   8
   9 _json_set_var() {
  10         local ___var="$1"
  11         local ___val="$2"
  12         eval "${JSON_PREFIX}$___var=\"\$___val\""
  13 }
  14
  15 _jshn_append() {
  16         local __var="$1"
  17         local __value="$2"
  18         local __sep="${3:- }"
  19         local __old_val
  20
  21         _json_get_var __old_val "$__var"
  22         __value="${__old_val:+$__old_val$__sep}$__value"
  23         _json_set_var "$__var" "$__value"
  24 }
  25
  26 _json_export() {
  27         local __var="${JSON_PREFIX}$1"
  28         local __val="$2"
  29
  30         export -- "$__var=$__val"
  31         _jshn_append "JSON_UNSET" "$__var"
  32 }
  33
  34 _json_add_key() {
  35         local table="$1"
  36         local var="$2"
  37         _jshn_append "KEYS_${table}" "$var"
  38 }
  39
  40 _get_var() {
  41         local __dest="$1"
  42         local __var="$2"
  43         eval "$__dest=\"\$$__var\""
  44 }
  45
  46 _set_var() {
  47         local __var="$1"
  48         local __val="$2"
  49         eval "$__var=\"\$__val\""
  50 }
  51
  52 _json_inc() {
  53         local _var="$1"
  54         local _dest="$2"
  55         local _seq
  56
  57         _json_get_var _seq "$_var"
  58         _seq="$((${_seq:-0} + 1))"
  59         _json_set_var "$_var" "$_seq"
  60         [ -n "$_dest" ] && _set_var "$_dest" "$_seq"
  61 }
  62
  63 _json_stack_push() {
  64         local new_cur="$1"
  65         local cur
  66
  67         _json_get_var cur JSON_CUR
  68         _jshn_append JSON_STACK "$cur"
  69         _json_set_var JSON_CUR "$new_cur"
  70 }
  71
  72 _json_add_generic() {
  73         local type="$1"
  74         local var="$2"
  75         local val="$3"
  76         local cur="$4"
  77
  78         [ -n "$cur" ] || _json_get_var cur JSON_CUR
  79
  80         if [ "${cur%%[0-9]*}" = "JSON_ARRAY" ]; then
  81                 _json_inc "SEQ_$cur" var
  82         else
  83                 local name="${var//[^a-zA-Z0-9_]/_}"
  84                 [[ "$name" == "$var" ]] || _json_export "NAME_${cur}_${name}" "$var"
  85                 var="$name"
  86         fi
  87
  88         _json_export "${cur}_$var" "$val"
  89         _json_export "TYPE_${cur}_$var" "$type"
  90         _json_add_key "$cur" "$var"
  91 }
  92
  93 _json_add_table() {
  94         local name="$1"
  95         local type="$2"
  96         local itype="$3"
  97         local cur new_cur
  98         local seq
  99
 100         _json_get_var cur JSON_CUR
 101         _json_inc JSON_SEQ seq
 102
 103         local table="JSON_$itype$seq"
 104         _json_export "UP_$table" "$cur"
 105         _json_export "KEYS_$table" ""
 106         [ "$itype" = "ARRAY" ] && _json_export "SEQ_$table" ""
 107         _json_stack_push "$table"
 108
 109         _json_get_var new_cur JSON_CUR
 110         _json_add_generic "$type" "$1" "$new_cur" "$cur"
 111 }
 112
 113 _json_close_table() {
 114         local stack new_stack
 115
 116         _json_get_var stack JSON_STACK
 117         _json_set_var JSON_CUR "${stack##* }"
 118         new_stack="${stack% *}"
 119         [[ "$stack" == "$new_stack" ]] && new_stack=
 120         _json_set_var JSON_STACK "$new_stack"
 121 }
 122
 123 json_set_namespace() {
 124         local _new="$1"
 125         local _old="$2"
 126
 127         [ -n "$_old" ] && _set_var "$_old" "$JSON_PREFIX"
 128         JSON_PREFIX="$_new"
 129 }
 130
 131 json_cleanup() {
 132         local unset
 133
 134         _json_get_var unset JSON_UNSET
 135         [ -n "$unset" ] && eval "unset $unset"
 136
 137         unset \
 138                 ${JSON_PREFIX}JSON_SEQ \
 139                 ${JSON_PREFIX}JSON_STACK \
 140                 ${JSON_PREFIX}JSON_CUR \
 141                 ${JSON_PREFIX}JSON_UNSET \
 142                 ${JSON_PREFIX}KEYS_JSON_VAR \
 143                 ${JSON_PREFIX}TYPE_JSON_VAR
 144 }
 145
 146 json_init() {
 147         json_cleanup
 148         export -- \
 149                 ${JSON_PREFIX}JSON_SEQ=0 \
 150                 ${JSON_PREFIX}JSON_STACK= \
 151                 ${JSON_PREFIX}JSON_CUR="JSON_VAR" \
 152                 ${JSON_PREFIX}JSON_UNSET="" \
 153                 ${JSON_PREFIX}KEYS_JSON_VAR= \
 154                 ${JSON_PREFIX}TYPE_JSON_VAR=
 155 }
 156
 157 json_add_object() {
 158         _json_add_table "$1" object TABLE
 159 }
 160
 161 json_close_object() {
 162         _json_close_table
 163 }
 164
 165 json_add_array() {
 166         _json_add_table "$1" array ARRAY
 167 }
 168
 169 json_close_array() {
 170         _json_close_table
 171 }
 172
 173 json_add_string() {
 174         _json_add_generic string "$1" "$2"
 175 }
 176
 177 json_add_int() {
 178         _json_add_generic int "$1" "$2"
 179 }
 180
 181 json_add_boolean() {
 182         _json_add_generic boolean "$1" "$2"
 183 }
 184
 185 # functions read access to json variables
 186
 187 json_load() {
 188         eval `jshn -r "$1"`
 189 }
 190
 191 json_dump() {
 192         jshn "$@" ${JSON_PREFIX:+-p "$JSON_PREFIX"} -w
 193 }
 194
 195 json_get_type() {
 196         local dest="$1"
 197         local cur
 198
 199         _json_get_var cur JSON_CUR
 200         local var="${JSON_PREFIX}TYPE_${cur}_${2//[^a-zA-Z0-9_]/_}"
 201         eval "export -- \"$dest=\${$var}\"; [ -n \"\${$var+x}\" ]"
 202 }
 203
 204 json_get_var() {
 205         local __dest="$1"
 206         local __cur
 207
 208         _json_get_var __cur JSON_CUR
 209         local __var="${JSON_PREFIX}${__cur}_${2//[^a-zA-Z0-9_]/_}"
 210         eval "export -- \"$__dest=\${$__var}\"; [ -n \"\${$__var+x}\" ]"
 211 }
 212
 213 json_get_vars() {
 214         while [ "$#" -gt 0 ]; do
 215                 local _var="$1"; shift
 216                 json_get_var "$_var" "$_var"
 217         done
 218 }
 219
 220 json_select() {
 221         local target="$1"
 222         local type
 223         local cur
 224
 225         [ -z "$1" ] && {
 226                 _json_set_var JSON_CUR "JSON_VAR"
 227                 return 0
 228         }
 229         [[ "$1" == ".." ]] && {
 230                 _json_get_var cur JSON_CUR
 231                 _json_get_var cur "UP_$cur"
 232                 _json_set_var JSON_CUR "$cur"
 233                 return 0
 234         }
 235         json_get_type type "$target"
 236         case "$type" in
 237                 object|array)
 238                         json_get_var cur "$target"
 239                         _json_set_var JSON_CUR "$cur"
 240                 ;;
 241                 *)
 242                         echo "WARNING: Variable '$target' does not exist or is not an array/object"
 243                         return 1
 244                 ;;
 245         esac
 246 }
 247
 248 json_is_a() {
 249         local type
 250
 251         json_get_type type "$1"
 252         [ "$type" = "$2" ]
 253 }