Custom tokens format replaces 0 by '-' about morgan HOT 5 CLOSED

It's intentional, because it'll also turn empty strings to -, which the proposed solution won't. The thing to do is return a string from your token function:

morgan.token('id', function (req) {
  return String(req.id)
})

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Basically the gist of it is that your token functions should be returning strings, not other things like numbers :)

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Okay, so it should probably be documented on the README.

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Ok, done!

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Thanks!

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