Export JSON to environment variables in BASH

I need these key/value pairs from JSON exported to the environment

There have been a few times where I've needed to take the contents of a JSON object and export them to the environment. While there are surely lots of way to do this with awk, sed and/or jq in combination, I've opted to just create a bash function for it.

An input file called config.json

Just a file with two key/value pairs, which will be used in the example below.

{

"XYZ_NAME": "test this!",

"XYZ_PATH": "/tmp/foo"

}

The JQ syntax used in the function

to_entries

Here we change the key/value object, into an array of consistent looking objects we can loop over.

# Input

{"XYZ_NAME":"test this!","XYZ_PATH":"/tmp/foo"}

# Output

[{"key":"XYZ_NAME","value":"test"},{"key":"XYZ_PATH","value":"/tmp/foo"}]

map("\(.key)=\(.value)")

By looping over each consistent object, we create an array with strings of key/value pairs.

# Input

[{"key":"XYZ_NAME","value":"test"},{"key":"XYZ_PATH","value":"/tmp/foo"}]

# Output

["XYZ_NAME=test this!","XYZ_PATH=/tmp/foo"]

.[]

We now only extract the strings from within the array.

# Input:

["XYZ_NAME=test this!","XYZ_PATH=/tmp/foo"]

# Output:

XYZ_NAME=test this!

XYZ_PATH=/tmp/foo

Throwing this all into a bash function

The reason this has to be a function vs. a script, is because in order for the enviroment variables to persist in the active shell after the script terminates.

function export_json_to_env () {

INPUT_FILE="${1}"

while IFS=$'\t\n' read -r LINE; do

export "${LINE}"

done < <(

<"${INPUT_FILE}" jq \

--compact-output \

--raw-output \

--monochrome-output \

--from-file \

<(echo 'to_entries | map("\(.key)=\(.value)") | .[]')

)

}

The while; do ... done loops over each row returned from the jq command, which is piped into the loop using Process Substitution. It then exports each key value pair.

--from-file also uses Process Subsitution, in order to pretend it's pulling data from a JQ filter file.

The result of invoking the function with a file

#!/usr/bin/env bash

env | grep "YY\_" || echo -e "BEFORE: not found\n"

export_json_to_env "config.json"

echo "AFTER:"; env | grep "YY\_"

BEFORE: not found

AFTER:

XYZ_PATH=/tmp/foo

XYZ_NAME=test this!