Example for parsing distro info from json

distros.json

{
    "amazon2": {
        "qcow": "amzn2-kvm-2.0.20190313-x86_64.xfs.gpt.qcow2",
        "os_type": "linux",
        "os_variant": "auto",
        "image_url": "https://cdn.amazonlinux.com/os-images/2.0.20190313/kvm",
        "disk_format": "qcow2",
        "login_user": "ec2-user"
    },

    "centos8": {
        "qcow": "CentOS-8-GenericCloud-8.1.1911-20200113.3.x86_64.qcow2",
        "os_variant": "centos8",
        "image_url": "https://cloud.centos.org/centos/8/x86_64/images",
        "disk_format": "qcow2",
        "login_user": "centos"
    }
}

example.sh

#!/bin/bash


distro_from_json() {
    local distro_name=$1
    local distros_file=$2

    # if $distro_name not defined in json
    if ! cat $distros_file | jq -e ".${distro_name}" > /dev/null; then
        QCOW=
        OS_TYPE=
        OS_VARIANT=
        IMAGE_URL=
        DISK_FORMAT=
        LOGIN_USER=
        return
    fi

    QCOW=$(cat $distros_file | jq ".${distro_name}.qcow")
    OS_TYPE=$(cat $distros_file | jq ".${distro_name}.os_type")
    OS_VARIANT=$(cat $distros_file | jq ".${distro_name}.os_variant")
    IMAGE_URL=$(cat $distros_file | jq ".${distro_name}.image_url")
    DISK_FORMAT=$(cat $distros_file | jq ".${distro_name}.disk_format")
    LOGIN_USER=$(cat $distros_file | jq ".${distro_name}.login_user")
}

print_vars() {
    echo "qcow: ${QCOW}"
    echo "os_type: ${OS_TYPE}"
    echo "os_variant: ${OS_VARIANT}"
    echo "image_url: ${IMAGE_URL}"
    echo "disk_format: ${DISK_FORMAT}"
    echo "login_user: ${LOGIN_USER}"
    echo -e "---------------------------\n"
}

echo "Vars for centos8:"
distro_from_json centos8 distros.json
print_vars

echo "Vars for amazon2:"
distro_from_json amazon2 distros.json
print_vars

echo "Vars for non-existing:"
distro_from_json centos7 distros.json
print_vars