sh/jshn.sh

   1 # functions for parsing and generating json
   2
   3 _json_get_var() {
   4         # dest=$1
   5         # var=$2
   6         eval "$1=\"\$${JSON_PREFIX}$2\""
   7 }
   8
   9 _json_set_var() {
  10         # var=$1
  11         local ___val="$2"
  12         eval "${JSON_PREFIX}$1=\"\$___val\""
  13 }
  14
  15 __jshn_raw_append() {
  16         # var=$1
  17         local value="$2"
  18         local sep="${3:- }"
  19
  20         eval "export -- \"$1=\${$1:+\${$1}\${value:+\$sep}}\$value\""
  21 }
  22
  23 _jshn_append() {
  24         # var=$1
  25         local _a_value="$2"
  26         eval "${JSON_PREFIX}$1=\"\${${JSON_PREFIX}$1} \$_a_value\""
  27 }
  28
  29 _get_var() {
  30         # var=$1
  31         # value=$2
  32         eval "$1=\"\$$2\""
  33 }
  34
  35 _set_var() {
  36         # var=$1
  37         local __val="$2"
  38         eval "$1=\"\$__val\""
  39 }
  40
  41 _json_inc() {
  42         # var=$1
  43         # dest=$2
  44
  45         let "${JSON_PREFIX}$1 += 1" "$2 = ${JSON_PREFIX}$1"
  46 }
  47
  48 _json_add_generic() {
  49         # type=$1
  50         # name=$2
  51         # value=$3
  52         # cur=$4
  53
  54         local var
  55         if [ "${4%%[0-9]*}" = "J_A" ]; then
  56                 _json_inc "S_$4" var
  57         else
  58                 var="${2//[^a-zA-Z0-9_]/_}"
  59                 [[ "$var" == "$2" ]] || export -- "${JSON_PREFIX}N_${4}_${var}=$2"
  60         fi
  61
  62         export -- \
  63                 "${JSON_PREFIX}${4}_$var=$3" \
  64                 "${JSON_PREFIX}T_${4}_$var=$1"
  65         _jshn_append "JSON_UNSET" "${4}_$var"
  66         _jshn_append "K_$4" "$var"
  67 }
  68
  69 _json_add_table() {
  70         # name=$1
  71         # type=$2
  72         # itype=$3
  73         local cur seq
  74
  75         _json_get_var cur JSON_CUR
  76         _json_inc JSON_SEQ seq
  77
  78         local table="J_$3$seq"
  79         _json_set_var "U_$table" "$cur"
  80         export -- "${JSON_PREFIX}K_$table="
  81         unset "${JSON_PREFIX}S_$table"
  82         _json_set_var JSON_CUR "$table"
  83         _jshn_append "JSON_UNSET" "$table"
  84
  85         _json_add_generic "$2" "$1" "$table" "$cur"
  86 }
  87
  88 _json_close_table() {
  89         local _s_cur
  90
  91         _json_get_var _s_cur JSON_CUR
  92         _json_get_var "${JSON_PREFIX}JSON_CUR" "U_$_s_cur"
  93 }
  94
  95 json_set_namespace() {
  96         local _new="$1"
  97         local _old="$2"
  98
  99         [ -n "$_old" ] && _set_var "$_old" "$JSON_PREFIX"
 100         JSON_PREFIX="$_new"
 101 }
 102
 103 json_cleanup() {
 104         local unset tmp
 105
 106         _json_get_var unset JSON_UNSET
 107         for tmp in $unset J_V; do
 108                 unset \
 109                         ${JSON_PREFIX}U_$tmp \
 110                         ${JSON_PREFIX}K_$tmp \
 111                         ${JSON_PREFIX}S_$tmp \
 112                         ${JSON_PREFIX}T_$tmp \
 113                         ${JSON_PREFIX}N_$tmp \
 114                         ${JSON_PREFIX}$tmp
 115         done
 116
 117         unset \
 118                 ${JSON_PREFIX}JSON_SEQ \
 119                 ${JSON_PREFIX}JSON_CUR \
 120                 ${JSON_PREFIX}JSON_UNSET
 121 }
 122
 123 json_init() {
 124         json_cleanup
 125         export -n ${JSON_PREFIX}JSON_SEQ=0
 126         export -- \
 127                 ${JSON_PREFIX}JSON_CUR="J_V" \
 128                 ${JSON_PREFIX}K_J_V=
 129 }
 130
 131 json_add_object() {
 132         _json_add_table "$1" object T
 133 }
 134
 135 json_close_object() {
 136         _json_close_table
 137 }
 138
 139 json_add_array() {
 140         _json_add_table "$1" array A
 141 }
 142
 143 json_close_array() {
 144         _json_close_table
 145 }
 146
 147 json_add_string() {
 148         local cur
 149         _json_get_var cur JSON_CUR
 150         _json_add_generic string "$1" "$2" "$cur"
 151 }
 152
 153 json_add_int() {
 154         local cur
 155         _json_get_var cur JSON_CUR
 156         _json_add_generic int "$1" "$2" "$cur"
 157 }
 158
 159 json_add_boolean() {
 160         local cur
 161         _json_get_var cur JSON_CUR
 162         _json_add_generic boolean "$1" "$2" "$cur"
 163 }
 164
 165 json_add_double() {
 166         local cur
 167         _json_get_var cur JSON_CUR
 168         _json_add_generic double "$1" "$2" "$cur"
 169 }
 170
 171 json_add_null() {
 172         local cur
 173         _json_get_var cur JSON_CUR
 174         _json_add_generic null "$1" "" "$cur"
 175 }
 176
 177 json_add_fields() {
 178         while [ "$#" -gt 0 ]; do
 179                 local field="$1"
 180                 shift
 181
 182                 local name="${field%%=*}"
 183                 local val="${field#*=}"
 184                 [ "$name" != "$val" ] || val=""
 185
 186                 local type="${name#*:}"
 187                 [ "$type" != "$name" ] || type=string
 188                 name="${name%%:*}"
 189
 190                 case "$type" in
 191                         string|int|boolean|double)
 192                                 local cur
 193                                 _json_get_var cur JSON_CUR
 194                                 _json_add_generic "$type" "$name" "$val" "$cur"
 195                         ;;
 196                 esac
 197         done
 198 }
 199
 200 # functions read access to json variables
 201
 202 json_load() {
 203         eval "`jshn -r "$1"`"
 204 }
 205
 206 json_load_file() {
 207         eval "`jshn -R "$1"`"
 208 }
 209
 210 json_dump() {
 211         jshn "$@" ${JSON_PREFIX:+-p "$JSON_PREFIX"} -w
 212 }
 213
 214 json_get_type() {
 215         local __dest="$1"
 216         local __cur
 217
 218         _json_get_var __cur JSON_CUR
 219         local __var="${JSON_PREFIX}T_${__cur}_${2//[^a-zA-Z0-9_]/_}"
 220         eval "export -- \"$__dest=\${$__var}\"; [ -n \"\${$__var+x}\" ]"
 221 }
 222
 223 json_get_keys() {
 224         local __dest="$1"
 225         local _tbl_cur
 226
 227         if [ -n "$2" ]; then
 228                 json_get_var _tbl_cur "$2"
 229         else
 230                 _json_get_var _tbl_cur JSON_CUR
 231         fi
 232         local __var="${JSON_PREFIX}K_${_tbl_cur}"
 233         eval "export -- \"$__dest=\${$__var}\"; [ -n \"\${$__var+x}\" ]"
 234 }
 235
 236 json_get_values() {
 237         local _v_dest="$1"
 238         local _v_keys _v_val _select=
 239         local _json_no_warning=1
 240
 241         unset "$_v_dest"
 242         [ -n "$2" ] && {
 243                 json_select "$2" || return 1
 244                 _select=1
 245         }
 246
 247         json_get_keys _v_keys
 248         set -- $_v_keys
 249         while [ "$#" -gt 0 ]; do
 250                 json_get_var _v_val "$1"
 251                 __jshn_raw_append "$_v_dest" "$_v_val"
 252                 shift
 253         done
 254         [ -n "$_select" ] && json_select ..
 255
 256         return 0
 257 }
 258
 259 json_get_var() {
 260         local __dest="$1"
 261         local __cur
 262
 263         _json_get_var __cur JSON_CUR
 264         local __var="${JSON_PREFIX}${__cur}_${2//[^a-zA-Z0-9_]/_}"
 265         eval "export -- \"$__dest=\${$__var:-$3}\"; [ -n \"\${$__var+x}\${3+x}\" ]"
 266 }
 267
 268 json_get_vars() {
 269         while [ "$#" -gt 0 ]; do
 270                 local _var="$1"; shift
 271                 if [ "$_var" != "${_var#*:}" ]; then
 272                         json_get_var "${_var%%:*}" "${_var%%:*}" "${_var#*:}"
 273                 else
 274                         json_get_var "$_var" "$_var"
 275                 fi
 276         done
 277 }
 278
 279 json_select() {
 280         local target="$1"
 281         local type
 282         local cur
 283
 284         [ -z "$1" ] && {
 285                 _json_set_var JSON_CUR "J_V"
 286                 return 0
 287         }
 288         [[ "$1" == ".." ]] && {
 289                 _json_get_var cur JSON_CUR
 290                 _json_get_var cur "U_$cur"
 291                 _json_set_var JSON_CUR "$cur"
 292                 return 0
 293         }
 294         json_get_type type "$target"
 295         case "$type" in
 296                 object|array)
 297                         json_get_var cur "$target"
 298                         _json_set_var JSON_CUR "$cur"
 299                 ;;
 300                 *)
 301                         [ -n "$_json_no_warning" ] || \
 302                                 echo "WARNING: Variable '$target' does not exist or is not an array/object"
 303                         return 1
 304                 ;;
 305         esac
 306 }
 307
 308 json_is_a() {
 309         local type
 310
 311         json_get_type type "$1"
 312         [ "$type" = "$2" ]
 313 }
 314
 315 json_for_each_item() {
 316         [ "$#" -ge 2 ] || return 0
 317         local function="$1"; shift
 318         local target="$1"; shift
 319         local type val
 320
 321         json_get_type type "$target"
 322         case "$type" in
 323                 object|array)
 324                         local keys key
 325                         json_select "$target"
 326                         json_get_keys keys
 327                         for key in $keys; do
 328                                 json_get_var val "$key"
 329                                 eval "$function \"\$val\" \"\$key\" \"\$@\""
 330                         done
 331                         json_select ..
 332                 ;;
 333                 *)
 334                         json_get_var val "$target"
 335                         eval "$function \"\$val\" \"\" \"\$@\""
 336                 ;;
 337         esac
 338 }