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flattenObject

JS TODO

Flatten an object with the paths for keys.

Use recursion. Use Object.keys(obj) combined with Array.prototype.reduce() to convert every leaf node to a flattened path node. If the value of a key is an object, the function calls itself with the appropriate prefix to create the path using Object.assign(). Otherwise, it adds the appropriate prefixed key-value pair to the accumulator object. You should always omit the second argument, prefix, unless you want every key to have a prefix.

const flattenObject = (obj, prefix = "") =>
Object.keys(obj).reduce((acc, k) => {
const pre = prefix.length ? prefix + "." : "";
if (typeof obj[k] === "object")
Object.assign(acc, flattenObject(obj[k], pre + k));
else acc[pre + k] = obj[k];
return acc;
}, {});
flattenObject({ a: { b: { c: 1 } }, d: 1 }); // { 'a.b.c': 1, d: 1 }