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Entry  05 Apr 2013, Konstantin Olchanski, Info, ODB JSON support 
    Reply  10 May 2013, Konstantin Olchanski, Info, mhttpd JSON support 
       Reply  17 May 2013, Konstantin Olchanski, Info, mhttpd JSON-P support 
          Reply  31 May 2013, Konstantin Olchanski, Info, mhttpd JSON-P support 
    Reply  27 Sep 2013, Konstantin Olchanski, Info, ODB JSON support 
       Reply  09 Oct 2013, Konstantin Olchanski, Info, ODB JSON support 
          Reply  17 Mar 2014, Konstantin Olchanski, Info, ODB JSON support 
             Reply  12 Apr 2022, Konstantin Olchanski, Info, ODB JSON support 
                Reply  13 Apr 2022, Stefan Ritt, Info, ODB JSON support 
                   Reply  13 Apr 2022, Konstantin Olchanski, Info, ODB JSON support 
Message ID: 872     Entry time: 05 Apr 2013     Reply to this: 886   916
Author: Konstantin Olchanski 
Topic: Info 
Subject: ODB JSON support 
odbedit can now save ODB in JSON-formatted files. (JSON is a popular data encoding standard associated 
with Javascript). The intent is to eventually use the ODB JSON encoder in mhttpd to simplify passing of 
ODB data to custom web pages. In mhttpd I also intend to support the JSON-P variation of JSON (via the 
jQuery "callback=?" notation).

JSON encoding implementation follows specifications at:
http://json.org/
http://www.json-p.org/
http://api.jquery.com/jQuery.getJSON/  (seek to JSONP)

The result passes validation by:
http://jsonlint.com/

Added functions:
   INT EXPRT db_save_json(HNDLE hDB, HNDLE hKey, const char *file_name);
   INT EXPRT db_copy_json(HNDLE hDB, HNDLE hKey, char **buffer, int *buffer_size, int *buffer_end, int 
save_keys, int follow_links);

For example of using this code, see odbedit.c and odb.c::db_save_json().

Example json file:

Notes:
1) hex numbers are quoted "0x1234" - JSON does not permit "hex numbers", but Javascript will 
automatically convert strings containing hex numbers into proper integers.
2) "double" is encoded with full 15 digit precision, "float" with full 7 digit precision. If floating point values 
are actually integers, they are encoded as integers (10.0 -> "10" if (value == (int)value)).
3) in this example I deleted all the "name/key" entries except for "stringvalue" and "sbyte2". I use the 
"/key" notation for ODB KEY data because the "/" character cannot appear inside valid ODB entry names. 
Normally, depending on the setting of "save_keys" argument, KEY data is present or absent for all entries.

ladd03:midas$ odbedit
[local:testexpt:S]/>cd /test
[local:testexpt:S]/test>save test.js
[local:testexpt:S]/test>exit
ladd03:midas$ more test.js
# MIDAS ODB JSON
# FILE test.js
# PATH /test
{
  "test" : {
    "intarr" : [ 15, 0, 0, 3, 0, 0, 0, 0, 0, 9 ],
    "dblvalue" : 2.2199999999999999e+01,
    "fltvalue" : 1.1100000e+01,
    "dwordvalue" : "0x0000007d",
    "wordvalue" : "0x0141",
    "boolvalue" : true,
    "stringvalue" : [ "aaa123bbb", "", "", "", "", "", "", "", "", "" ],
    "stringvalue/key" : {
      "type" : 12,
      "num_values" : 10,
      "item_size" : 1024,
      "last_written" : 1288592982
    },
    "byte1" : 10,
    "byte2" : 241,
    "char1" : "1",
    "char2" : "-",
    "sbyte1" : 10,
    "sbyte2" : -15,
    "sbyte2/key" : {
      "type" : 2,
      "last_written" : 1365101364
    }
  }
}

svn rev 5356
K.O.
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