Accrue.Dunning.Engine behaviour (accrue v1.4.0)

Behaviour for dunning campaign orchestration engines (DUN-03, D-01).

Engines control which orchestration system is invoked at campaign boundaries. DB state (dunning_campaign_started_at on accrue_subscriptions) is managed by Accrue regardless of engine choice — the engine only decides how the resulting Oban jobs or external workflows are enqueued and cancelled.

Built-in engine

Accrue.Dunning.Engine.Oban is always-on and requires no additional configuration. It wraps the existing Oban-backed DunningStep worker.

Optional Chimeway engine

Accrue.Integrations.Chimeway is off by default and conditionally compiled when the optional :chimeway dependency is present. To opt in:

# config/config.exs
config :accrue, dunning: [engine: Accrue.Integrations.Chimeway]

The :chimeway dep must also be added to the host mix.exs:

{:chimeway, "~> 1.0"}

Dispatch

The engine is invoked directly via Config.dunning_engine().start_campaign(...). This module is behaviour-only — no facade delegation functions are defined here, unlike Accrue.Auth.

Summary

Callbacks

cancel_campaign(subscription, iso_anchor, opts)

start_campaign(subscription, anchor_at, opts)

Callbacks

cancel_campaign(subscription, iso_anchor, opts)

@callback cancel_campaign(
  subscription :: Accrue.Billing.Subscription.t(),
  iso_anchor :: String.t(),
  opts :: keyword()
) :: :ok | {:error, term()}

start_campaign(subscription, anchor_at, opts)

@callback start_campaign(
  subscription :: Accrue.Billing.Subscription.t(),
  anchor_at :: DateTime.t(),
  opts :: keyword()
) :: :ok | {:error, term()}