How to merge two Object of Object in JavaScript (NodeJS)

Question

I have multiple objects:

const obj1 = {
  db: {
    url: "mongodb://localhost:27017",
  },
};

const obj2 = {
  db: {
    user: "admin",
  },
};

const obj3 = {
  token: {
    auth: {
      secret: "*****",
    },
  },
};

How can merge into a single object like this:

{
    db: {
        url: "mongodb://localhost:27017",
        user: "admin"
    },
    token: {
        auth: {
            secret: "*****"
        }
    }
}

I just tried something like this: Object.assign(obj1, obj2) but is not what I want.

Answer 1

I suggest correcting the objects that aren't valid, as pointed out in the comments. Other than this, the following function works for as many objects as you want.

const obj1 = {
  db: {
    url: "mongodb://localhost:27017",
  },
};

const obj2 = {
  db: {
    user: "admin",
  },
};

const obj3 = {
  token: {
    auth: {
      secret: "*****",
    },
  },
};

function merge() {
  const result = {};

  for (let i = 0; i < arguments.length; i++) {
    const obj = arguments[i];

    for (const key in obj) {
      if (obj.hasOwnProperty(key)) {
        if (typeof obj[key] === "object") {
          result[key] = merge(result[key], obj[key]);
        } else {
          result[key] = obj[key];
        }
      }
    }
  }

  return result;
}

const merged = merge(obj1, obj2, obj3);
console.log(merged);