IdempotencyPlug.EctoStore (IdempotencyPlug v0.2.2)

Module that defines an Ecto store.

A migration file should be generated with mix idempotency_plug.ecto.gen.migration.

Performance considerations

For most workloads no tuning is needed — POST/PATCH traffic is rarely high enough for the table to become a bottleneck, and there are likely several downstream writes happening in the same request.

However, in high-write database workloads, WAL pressure may become a bottleneck. With Postgres this can be mitigated by setting the table to UNLOGGED to skip WAL entirely:

ALTER TABLE idempotency_plug_requests SET UNLOGGED

Unclean shutdowns are rare, but UNLOGGED is still only appropriate when losing the idempotency cache during recovery is acceptable. Not recommended for payments or other critical cases.

Examples

defmodule MyApp.Application do
  # ..

  def start(_type, _args) do
    children = [
      {IdempotencyPlug.RequestTracker, [
        store: {IdempotencyPlug.EctoStore, repo: MyApp.Repo}]}
      # ...
    ]

    Supervisor.start_link(children, strategy: :one_for_one, name: MyApp.Supervisor)
  end
end