Bash functions for JSON editor

json_config_lib.sh

#!/bin/bash

# Required packages:
# - python3
# - jq
#
# Install packages:
# - sudo apt-get install python3 jq

set -e

function f_write_config() {
    # Write JSON config file (./config.json)
    #
    # arg: $1 - key (string)
    # arg: $2 - value (string | json)

    local key="$1"
    local value="$2"

    # Validations

    # check if config.json exist
    if [ ! -f ./config.json ]; then
        echo "config.json not found"
        exit 1
    fi

    # check if config.json has valid json format
    if ! jq -e . > /dev/null 2>&1 < ./config.json; then
        echo "config.json has invalid json format"
        exit 1
    fi
    
    # add quotes if value is alpha-numeric
    # and encode $value to base64
    if [[ "$value" =~ ^[0-9]+$ ]]; then
        value_base64=$(echo -n \""$value\"" | base64)
    else
        value_base64=$(echo -n "$value" | base64)
    fi


    # Multiline adhoc run python code
    local result=$(python3 << EOF
import json
import base64

# read config file or create if not exists
try:
    with open('config.json', 'r') as f:
        content = json.load(f)
except:
    content = {}

# decode base64 value
value_decoded = base64.b64decode("$value_base64")

content.update({"$key": json.loads(value_decoded)})
json_content = json.dumps(content)

# save to file
with open("./config.json", "w") as f:
    f.write(json_content)
EOF
)
}

function f_get_config() {
    # Get JSON config file (./config.json)
    # arg: $1 - key (string)
    #
    # return: $value (string | json)
    
    local key="$1"

    # Get key from config with jq
    value=$(cat ./config.json | jq -r ".$key")
}


# How to use
# example
f_write_config aws_region "us-east-1"
f_write_config aws_credentials '{"access_key": "1234", "secret_key": "5678"}'

f_get_config aws_region

echo $value

cat ./config.json | jq .