node.js TypeError: path must be absolute or specify root to res.sendFile [failed to parse JSON]
The error is pretty clear, you need to specify an absolute (instead of relative) path and/or set root in the config object for res.sendFile(). Examples:
// assuming index.html is in the same directory as this scriptres.sendFile(__dirname + '/index.html');or specify a root (which is used as the base path for the first argument to res.sendFile():
res.sendFile('index.html', { root: __dirname });Specifying the root path is more useful when you're passing a user-generated file path which could potentially contain malformed/malicious parts like .. (e.g. ../../../../../../etc/passwd). Setting the root path prevents such malicious paths from being used to access files outside of that base path.
in .mjs files we for now don't have __dirname
hence
res.sendFile('index.html', { root: '.' })
Try adding root path.
app.get('/', function(req, res) { res.sendFile('index.html', { root: __dirname });});