# `mix letterbox.install`
[🔗](https://github.com/hattoriai/letterbox/blob/v0.1.0-rc.0/lib/mix/tasks/letterbox.install.ex#L1)

Installs Letterbox in a Phoenix application.

    $ mix igniter.install letterbox

or, with Letterbox already in the deps, `mix letterbox.install`.
[Igniter](https://hexdocs.pm/igniter) shows each change as a diff
before it writes, and running the task again changes nothing:

  * the router has the ingresses' webhooks, in a pipeline of their own
    with no session and no CSRF token:

        pipeline :webhooks do
          plug :accepts, ["json"]
        end

        scope "/inbound" do
          pipe_through :webhooks
          post "/webhooks/:ingress", Letterbox.Plug, []
        end

    The app's to change: the path, the scope and the pipeline (see
    `Letterbox.Plug`). Run again, the task finds the route by its plug,
    wherever it is, and adds no other.
  * the migration of Letterbox's table (`mix letterbox.gen.migration`);
  * `.formatter.exs` imports Letterbox's, so routes are written
    `route "support@", to: …`;
  * `config :letterbox, repo: MyApp.Repo, routing: MyApp.Mailboxes`;
  * `lib/my_app/mailboxes.ex`, the routes, which give every message to
    `lib/my_app/mailboxes/inbox.ex`, a first mailbox that logs what it
    gets: the app's own files, written once;
  * the application starts `Letterbox.Sweeper` after the repo: messages
    that were waiting are resumed, and those done with for 30 days are
    deleted.

  * the endpoint's `Plug.Parsers` keeps a webhook's body as it was sent,
    for its signature (`PhoenixMountable.RawBody`).

Then say how messages reach the app, in `config/runtime.exs`
(`Letterbox.Ingress`).

---

*Consult [api-reference.md](api-reference.md) for complete listing*