How to override errors in phoenix?

Question

I build restful api (json) on phoenix. And I did not need the support of html.

How to override errors in phoenix? Example errors: - 500 - 404 when no route found and other.

Answer 1

For those who may have the same issues I had, there a couple of steps required to render JSON for 404 and 500 responses.

Firstly add render("404.json", _assigns) and render("500.json", _assigns) to your app's web/views/error_view.ex file.

For example:

defmodule MyApp.ErrorView do
  use MyApp.Web, :view

  def render("404.json", _assigns) do
    %{errors: %{message: "Not Found"}}
  end

  def render("500.json", _assigns) do
    %{errors: %{message: "Server Error"}}
  end
end

Then in your config/config.exs file updated the default_format to "json".

config :my_app, MyApp.Endpoint,
  render_errors: [default_format: "json"]

Note that if your app is purely a REST api this will be fine, but be careful in the event you also render HTML responses as now by default errors will be rendered as json.