metro.fetch: Missing URL Parameter

This error occurs when you call metro.fetch(req) and req.url is not set or empty.

The metro.fetch() function has two parameters:

req: either a Request object or a URL object or string
options: (Optional) an options object, with valid parameters for a Request, or a URL object or string.

Either the req or the options object should specify a URL, e.g:

let req = metro.request('https://www.example.com/')
let response = await metro.fetch(req)

Or, by overriding req.url in the second parameter:

let response = await metro.fetch(req, 'https://www.example.com/')

Or, explicitly:

let response = await metro.fetch(req, { 
	url: 'https://www.example.com/' 
})