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 # functions read access to json variables
 178
 179 json_load() {
 180         eval "`jshn -r "$1"`"
 181 }
 182
 183 json_load_file() {
 184         eval "`jshn -R "$1"`"
 185 }
 186
 187 json_dump() {
 188         jshn "$@" ${JSON_PREFIX:+-p "$JSON_PREFIX"} -w
 189 }
 190
 191 json_get_type() {
 192         local __dest="$1"
 193         local __cur
 194
 195         _json_get_var __cur JSON_CUR
 196         local __var="${JSON_PREFIX}T_${__cur}_${2//[^a-zA-Z0-9_]/_}"
 197         eval "export -- \"$__dest=\${$__var}\"; [ -n \"\${$__var+x}\" ]"
 198 }
 199
 200 json_get_keys() {
 201         local __dest="$1"
 202         local _tbl_cur
 203
 204         if [ -n "$2" ]; then
 205                 json_get_var _tbl_cur "$2"
 206         else
 207                 _json_get_var _tbl_cur JSON_CUR
 208         fi
 209         local __var="${JSON_PREFIX}K_${_tbl_cur}"
 210         eval "export -- \"$__dest=\${$__var}\"; [ -n \"\${$__var+x}\" ]"
 211 }
 212
 213 json_get_values() {
 214         local _v_dest="$1"
 215         local _v_keys _v_val _select=
 216         local _json_no_warning=1
 217
 218         unset "$_v_dest"
 219         [ -n "$2" ] && {
 220                 json_select "$2" || return 1
 221                 _select=1
 222         }
 223
 224         json_get_keys _v_keys
 225         set -- $_v_keys
 226         while [ "$#" -gt 0 ]; do
 227                 json_get_var _v_val "$1"
 228                 __jshn_raw_append "$_v_dest" "$_v_val"
 229                 shift
 230         done
 231         [ -n "$_select" ] && json_select ..
 232
 233         return 0
 234 }
 235
 236 json_get_var() {
 237         local __dest="$1"
 238         local __cur
 239
 240         _json_get_var __cur JSON_CUR
 241         local __var="${JSON_PREFIX}${__cur}_${2//[^a-zA-Z0-9_]/_}"
 242         eval "export -- \"$__dest=\${$__var:-$3}\"; [ -n \"\${$__var+x}\${3+x}\" ]"
 243 }
 244
 245 json_get_vars() {
 246         while [ "$#" -gt 0 ]; do
 247                 local _var="$1"; shift
 248                 if [ "$_var" != "${_var#*:}" ]; then
 249                         json_get_var "${_var%%:*}" "${_var%%:*}" "${_var#*:}"
 250                 else
 251                         json_get_var "$_var" "$_var"
 252                 fi
 253         done
 254 }
 255
 256 json_select() {
 257         local target="$1"
 258         local type
 259         local cur
 260
 261         [ -z "$1" ] && {
 262                 _json_set_var JSON_CUR "J_V"
 263                 return 0
 264         }
 265         [[ "$1" == ".." ]] && {
 266                 _json_get_var cur JSON_CUR
 267                 _json_get_var cur "U_$cur"
 268                 _json_set_var JSON_CUR "$cur"
 269                 return 0
 270         }
 271         json_get_type type "$target"
 272         case "$type" in
 273                 object|array)
 274                         json_get_var cur "$target"
 275                         _json_set_var JSON_CUR "$cur"
 276                 ;;
 277                 *)
 278                         [ -n "$_json_no_warning" ] || \
 279                                 echo "WARNING: Variable '$target' does not exist or is not an array/object"
 280                         return 1
 281                 ;;
 282         esac
 283 }
 284
 285 json_is_a() {
 286         local type
 287
 288         json_get_type type "$1"
 289         [ "$type" = "$2" ]
 290 }
 291
 292 json_for_each_item() {
 293         [ "$#" -ge 2 ] || return 0
 294         local function="$1"; shift
 295         local target="$1"; shift
 296         local type val
 297
 298         json_get_type type "$target"
 299         case "$type" in
 300                 object|array)
 301                         local keys key
 302                         json_select "$target"
 303                         json_get_keys keys
 304                         for key in $keys; do
 305                                 json_get_var val "$key"
 306                                 eval "$function \"\$val\" \"\$key\" \"\$@\""
 307                         done
 308                         json_select ..
 309                 ;;
 310                 *)
 311                         json_get_var val "$target"
 312                         eval "$function \"\$val\" \"\" \"\$@\""
 313                 ;;
 314         esac
 315 }