Quicktip: Customize look of form validation in Phoenix

When submitting a form in a Phoenix and get validation errors, you are displayed with a little validation error text. However, you probably want to customize how that error message is displayed. For example, what I don't like is that it just say

"can't be blank"

And also, the class that is attached is not compatible with Tailwind or Bootstrap. So, for my use case I want it to have both the field name attached and some Tailwind classes.

To accomplish that, you can do that in the file: lib/tutorialweb/views/errorhelpers.ex

So, out of the box, the code looks something like this:

def error_tag(form, field) do
  Enum.map(Keyword.get_values(form.errors, field), fn error ->
    content_tag(:span, translate_error(error), class: "help-block")
  end)
end

And change it to something like this:

def error_tag(form, field) do
  Enum.map(Keyword.get_values(form.errors, field), fn error ->
    field = field |> Atom.to_string() |> String.capitalize()
    content_tag(:span, "#{field} #{translate_error(error)}", class: "block mt-1 text-sm text-red-700")
  end)
end

END RESULT