How to parse the values and assign to my local variable in windows bash? - windows

Question

I have a json file
input= {
"credentials": {
"accessKeyId": "123456789",
"secretAccessKey": "654321",
"sessionToken": "valuedummy",
"expiration": "201925"
}
}
I am trying to parse the value and assign to a local variable using windows bash.
What I am trying to achieve is:
Assign the values to my local variables a,b,c,d
a=123456789
b=654321
c=valuedummy
d=201925
How can I do this?

Answer 1

jq is a reasonable approach:
a=$( jq -r .credentials.accessKeyId input )
where input is this file:
{
"credentials": {
"accessKeyId": "123456789",
"secretAccessKey": "654321",
"sessionToken": "valuedummy",
"expiration": "201925"
}
}

Answer 2

You should definitely use tools that are meant to parse JSON, such as jq. You won't be able to do it reliably with sed, awk etc.:
$ cat file
{
"credentials": {
"accessKeyId": "123456789",
"secretAccessKey": "654321",
"sessionToken": "valuedummy",
"expiration": "201925"
}
}
$ cat script
#!/usr/bin/env bash
i=0 var=(a b c d)
while IFS= read -rd '' line; do
printf -v "${var[i++]:-tmp}" "$line"
done < <(jq -j '.credentials | to_entries[] | (.value + "\u0000")' file)
declare -p a b c d
$ ./script
declare -- a="123456789"
declare -- b="654321"
declare -- c="valuedummy"
declare -- d="201925"

Answer 3

A non jq answer, but requires json package and python (typically installed with standard distributions):
a=$( python -c 'import sys, json; print(json.load(sys.stdin)["credentials"]["accessKeyId"])' <input )
Edit: Here is a slightly more general answer (IMHO):
$ cat input
{
"credentials": {
"accessKeyId": "123456789",
"secretAccessKey": "654321",
"sessionToken": "valuedummy",
"expiration": "201925"
}
}
$ cat json2env
eval $(
python -c '
import sys, json
for (k,v) in (json.load(sys.stdin)["'$1'"]).items():
print(k + "=" + v)
' < $2
)
$ . json2env credentials input
$ echo $accessKeyId
123456789
$ echo $secretAccessKey
654321
It's slightly more general in that it will accept any json of a similar format ( dictionary containing a dictionary ) . I simply parameterized the dictionary attribute.
The python script basically prints all the name value pairs in the specified attribute ( in your case, "credentials" ). The name is used as the variable name. This is convenient but I suspect there are issues there with some symbols that may be acceptable in key names but not in variable names.