Using spread syntax to conditionally add JSON key, value to object. Fetch example using POST and Authorization.

conditional-json.js

export const POST = (auth) => ({
  method: "POST", // *GET, POST, PUT, DELETE, etc.
  mode: "cors", // no-cors, cors, *same-origin
  headers: {
    "Content-Type": "application/json",
    ...(auth ? { "Authorization": auth } : {})
  },
})

This is what I was looking for! Came from https://stackoverflow.com/questions/11704267/in-javascript-how-to-conditionally-add-a-member-to-an-object#40560953

Thank you, saved my day!

Very helpful, thanks!