JSFiddle - React, Tailwind, and code Playground

JavaScript

var response1 = JSON.parse("{    \"renditions\": {        \"live\": \"true\",        \" type\": \"default\",        \"rendition\": {            \"name\": \"Live \",            \"url\": \"http: //mysite\"        }    } }");

var response2 = JSON.parse("{    \"renditions\": {        \"live\": \"true\",        \" type\": \"default\",        \"rendition\":[ {            \"name\": \"Live \",            \"url\": \"http: //mysite\"        } ]   } }");


function modify(response) {
    if (Object.prototype.toString.call( response.renditions.rendition ) !== '[object Array]') {
        response.renditions.rendition = [response.renditions.rendition];
    }
    return response;
}

console.log("started as object: " + JSON.stringify(modify(response1)));
console.log("started as array: " + JSON.stringify(modify(response2)));