Parse JSON in bat file

I am calling a curl command in a batch file. The request gives me a JSON response. I store that JSON response in the file. I want to know how do I parse this JSON and fetch a specific attributes?

test.bat

%comspec% /c curl -L -c cookie -b cookie -X POST -H "Accept: application/json" -s -d "{\"id\":\"123456789\",\"part\":\"part\",\"duration\":1400}" https://abcd.com > MyIP.txt
set /p string1=<MyIP.txt

Above works fine and store the JSON in a file. A dummy response looks like the following:

{"aki":"abcd", "assumed":"cdef", "expiration":12345, "sa":"temp/abcdefgh", "st":"abcd+/00'nget"}

I need to get 'aki' and 'sa' variables from this response and store them to an another file.

Solution

I tried one met honed in the thread you shared, but the output is coming as empty:

This is exactly the reason why it's not recommended to do this in cmd / batch-file without the proper tools.

While the code and JSON in your comment does work...

C:\>ECHO %other% %year% %value% %time%
1234 2016 str 05:01

...one of the things that will get you into trouble is the single quote within your original JSON response ("abcd+/00'nget"). You'll have to escape all the necessary characters to make this work. The JSON-parser xidel, with the output-format set to "cmd", does this for you:

C:\>ECHO {"aki":"abcd","assumed":"cdef","expiration":12345,"sa":"temp/abcdefgh","st":"abcd+/00'nget"} |^
    xidel -se "string:=$json" --output-format=cmd
SET string={^"aki^": ^"abcd^"^, ^"assumed^": ^"cdef^"^, ^"expiration^": 12345^, ^"sa^": ^"temp/abcdefgh^"^, ^"st^": ^"abcd+/00'nget^"}

So the following batch-file snippet should work:

SET string={^"aki^": ^"abcd^"^, ^"assumed^": ^"cdef^"^, ^"expiration^": 12345^, ^"sa^": ^"temp/abcdefgh^"^, ^"st^": ^"abcd+/00'nget^"}
SET string=%string:"=%
SET "string=%string:~1,-1%"
SET "string=%string:: ==%"
SET "%string:, =" & set "%"

ECHO %aki% %sa%

But I would recommend using Xidel right from the start, because it could (probably) do it all for you, while skipping the whole escape-characters issue:

C:\>xidel -s^
  -H "Cookie: [...]" -H "Accept: application/json"^
  -d "{serialize({'id':'123456789','part':'part','duration':1400},{'method':'json'})}"^
  "https://abcd.com"^
  -e "$json,$json/(aki,sa)"
{
  "aki": "abcd",
  "assumed": "cdef",
  "expiration": 12345,
  "sa": "temp/abcdefgh",
  "st": "abcd+/00'nget"
}
abcd
temp/abcdefgh