Que v0.10.1

View Source Que (Que v0.10.1)

Que is a simple background job processing library backed by Mnesia.

Que doesn't depend on any external services like Redis for persisting job state, instead uses the built-in erlang application mnesia. This makes it extremely easy to use as you don't need to install anything other than Que itself.

installation

 Installation

First add it as a dependency in your mix.exs and run mix deps.get:

defp deps do
  [{:que, "~> 0.10.1"}]
end

Then run $ mix deps.get and add it to your list of applications:

def application do
  [applications: [:que]]
end

usage

 Usage

Define a Worker to process your jobs:

defmodule App.Workers.ImageConverter do
  use Que.Worker

  def perform(image) do
    ImageTool.save_resized_copy!(image, :thumbnail)
    ImageTool.save_resized_copy!(image, :medium)
    ImageTool.save_resized_copy!(image, :large)
  end
end

You can now add jobs to be processed by the worker:

Que.add(App.Workers.ImageConverter, some_image)
#=> :ok

Read the Que.Worker documentation for other callbacks and concurrency options.

persist-to-disk

 Persist to Disk

By default, Que uses an in-memory Mnesia database so jobs are NOT persisted across application restarts. To do that, you first need to specify a path for your mnesia database in you config.exs.

config :mnesia, dir: 'mnesia/#{Mix.env}/#{node()}'
# Notice the single quotes

You can now call the que.setup mix task to create the job database:

$ mix que.setup

For compiled releases, see the Que.Persistence.Mnesia documentation.

Link to this section Summary

Functions

add(worker, arguments)

Enqueues a Job to be processed by Que.

start(type, args)

Starts the Que Application (and its Supervision Tree)

Link to this section Functions

Link to this function

add(worker, arguments)

View Source

Specs

add(worker :: module(), arguments :: term()) ::
  {:ok,
   %Que.Job{
     arguments: term(),
     created_at: term(),
     id: term(),
     pid: term(),
     ref: term(),
     status: term(),
     updated_at: term(),
     worker: term()
   }}

Enqueues a Job to be processed by Que.

Accepts the worker module name and a term to be passed to the worker as arguments.

example

 Example 

Que.add(App.Workers.FileDownloader, {"http://example.com/file/path.zip", "/some/local/path.zip"})
#=> :ok

Que.add(App.Workers.SignupMailer, to: "some@email.com", message: "Thank you for Signing up!")
#=> :ok
Link to this function

start(type, args)

View Source

Starts the Que Application (and its Supervision Tree)