Consider this simple function:
function enumerate(x, fn) {
if (x && typeof x === 'object') {
for (let val of Object.values(x)) {
fn(val);
enumerate(val, fn);
}
}
}
It walks through a nested object structure and invokes the given callback for each value it finds (no matter object or primitive). You can apply it to your structure and provide a callback that analyzes the value and, if it has the needed properties, adds it to an array, for example:
enumerate(yourData, function (val) {
if (val.start_location)
yourArray.push([val.start_location, val.end_location])
});
Hope this helps you getting started, good luck!
solved How to write recursive function javascript push my array property Json object?