JavaScript - get nested property value by path (resistant to null/undefined)

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// Custom function solution when property names can contain '.'

function getValue(object, path) {
    return path.reduce(function(value, key) {
        return value == null ? value : value[key];
    }, object);
}


// Usage example:

var myObject = {
    name: 'John',
    metadata: {
        type: 'json',
    },
};

var metadata = getValue(myObject, ['metadata', 'type']);

console.log(metadata); // json