Example custom mix task to seed the database using an existing seed file

gistfile1.txt

# lib/mix/tasks/musikr.seed.ex
defmodule Mix.Tasks.Musikr.Seed do
  use Mix.Task

  @shortdoc "Seeds the database"

  @moduledoc """
    Seed the database using the file 'priv/repo/seeds.exs'
  """

  def run(_args) do
    Code.eval_file("priv/repo/seeds.exs")
  end
end


# priv/repo/seeds.exs
instruments = ~w(piano violin viola cello bass horn tuba trombone clarinet flute oboe)
for i <- instruments do
  Musikr.Repo.insert!(%Musikr.Instrument{name: i})
end