404

You can set the 404 page in two ways, the function is identical and follows the same logic as that passed to the get or post methods.

# these are equivalent
app$not_found <- \(req, res){
  res$send(htmltools::h2("404"), status = 404L)
}

app$set_404(\(req, res){
  res$send(htmltools::h2("Not found"), status = 404L)
})