Using Logger.info and Logger.debug in ExUnit tests

Article autor
July 31, 2020
Using Logger.info and Logger.debug in ExUnit tests
Elixir Newsletter
Join Elixir newsletter

Subscribe to receive Elixir news to your inbox every two weeks.

Oops! Something went wrong while submitting the form.
Elixir Newsletter
Expand your skills

Download free e-books, watch expert tech talks, and explore open-source projects. Everything you need to grow as a developer - completely free.

Table of contents

By default in the test env, Phoenix doesn't show Logger.debug/Logger.info outputs in the console.

Logger provides 4 printing levels:

  • info (allows errors, warns, debugs, infos)
  • debug (allows errors, warns, debugs)
  • warn (allows errors, warns)
  • error (allows errors)

By default the :warn level is turned on. It means that only Logger.warn and Logger.error is printed to the output.

If you'd like to use another two, go to your config/test.exs file and you'll probably see:

# Print only warnings and errors during test
config :logger, level: :warn

Just change the line to the proper level (:debug or :info), and you're ready to go:

# Print all (errors, warnings, debugs and infos) during tests
config :logger, level: :info

Work with a team that keeps learning and building better software every day.

Related posts

Dive deeper into this topic with these related posts

No items found.

You might also like

Discover more content from this category

How to deal with timeout issue when debugging Phoenix app

There is a common scenario: You'd like to debug your Phoenix app with break!/4 or IEx.pry/0. Everything works fine, until... Phoenix server throws a timeout error statement.

How to process Phoenix conn after render before it is sent as a response

There are a bunch of operations you may want to perform before the rendered response in conn is sent to the client, such as minification. In this post I'll show you how to do it easily.

How to call useEffect React Hook on a component mount and unmount

With pure function React Components you're not allowed to use lifecycle methods like componentDidMount or componentWillUnmount.