OeditusCredo.Check.Warning.BlockingInPlug (OeditusCredo v0.5.0)

Basics

This check has a base priority of normal and works with any version of Elixir.

Explanation

Expensive blocking operations in Plug functions slow down request processing.

Move expensive operations to background jobs or async tasks.

Bad:

plug :load_user_data

def load_user_data(conn, _opts) do
  user = Repo.get!(User, conn.assigns.user_id)
  assign(conn, :user, user)
end

Good:

# Load user data in the controller action instead
def show(conn, params) do
  user = Repo.get!(User, params["id"])
  render(conn, "show.html", user: user)
end

Check-Specific Parameters

Use the following parameters to configure this check:

:exclude_test_files

Set to true to skip test files (default: false)

This parameter defaults to nil.

:extra_blocking_modules

Additional module atoms to treat as blocking (default: [])

This parameter defaults to nil.

General Parameters

Like with all checks, general params can be applied.

Parameters can be configured via the .credo.exs config file.