Introduction

Please read the detailed tutorial available at Odd Jobs Tutorial. Broadly, here is the most common way to get started with this library:

• Create a DB table to hold your jobs using the OddJobs.Migrations.createJobTable function.

• Create a sum-type to represent your job payloads, for example:

  data MyJob = SendWelcomeEmail Int
             | SendPasswordResetEmail Text
             | SetupSampleData Int
             deriving (Eq, Show, Generic, ToJSON, FromJSON)
  

• Ensure that you use a "tagged" JSON encoding for this data-type for best results (this is the default behaviour in Aeson). For example:

  Aeson.encode (SendWelcomeEmail 10) == "{\"tag\":\"SendWelcomeEmail\", \"contents\":10}"
  

• Create you "core" job-runner function:

  myJobRunner :: Job -> IO ()
  myJobRunner Job{jobPayload} = 
    case jobPayload of
      SendWelcomeEmail userId -> sendWelcomeEmail userId
      SendPasswordResetEmail tkn -> sendPasswordResetEmail tkn
      SetupSampleData userId -> sendPasswordResetEmail userId
  

• Use OddJobs.Job.createJob and OddJobs.Job.scheduleJob within your app whenever you want to enqueue a job.

• Use OddJobs.Cli to wrap all of this together into a nice CLI that can fork itself as a background daemon.

• Hook this up to your deployment scripts and you're good to go!