Drafter.Server (drafter v0.3.1)

Start SSH and Telnet servers for hosting TUI applications over the network.

Each connecting client gets their own session. Two modes are supported:

:isolated (default) — each client runs an independent app instance with its own state. Ideal for single-user tools, games, and dashboards.
:shared — all clients share the same app state. Input from any client mutates the shared state and all clients re-render. Ideal for collaborative apps, multi-player games, and shared dashboards.

SSH Example

Drafter.Server.start_ssh(ChatApp,
  port: 2222,
  mode: :shared,
  auth: [{"alice", "pass1"}, {"bob", "pass2"}]
)

Telnet Example

Drafter.Server.start_telnet(MyApp, port: 2323, mode: :isolated)

Generating SSH host keys

If no system_dir: is provided, host keys are automatically generated and cached in a temp directory. For production use, generate persistent keys:

ssh-keygen -t rsa -b 2048 -f /etc/drafter/ssh_host_rsa_key -N ""

Then pass system_dir: "/etc/drafter".

Summary

Functions

start_ssh(app_module, opts \\ [])

Starts an SSH server hosting app_module, linked to the caller.

start_telnet(app_module, opts \\ [])

Starts a Telnet server hosting app_module, linked to the caller.

Functions

start_ssh(app_module, opts \\ [])

@spec start_ssh(
  module(),
  keyword()
) :: {:ok, pid()} | {:error, term()}

Starts an SSH server hosting app_module, linked to the caller.

app_module is a module that does use Drafter.App. Returns {:ok, pid} for the listener, or {:error, reason}. The listener runs until it is stopped; each client that connects gets its own session process.

Options

:port - TCP port. Default 2222.
:ip - the interface to bind, as an address tuple. Default {127, 0, 0, 1}, which accepts only local connections.
:mode - :isolated (default) gives each client its own app state; :shared runs every client against one shared state.
:auth - [{username, password}] tuples for password authentication, or the atom :anonymous to accept any username and password. Default [{"admin", "admin"}].
:system_dir - path to the directory holding the SSH host keys. Default: a drafter_ssh directory under the system temp directory, with RSA host keys generated by ssh-keygen on first use.
:mount_props - map() handed to each session's mount/1. Default %{}. The authenticated username is added to it under :username as a string, so every SSH session's mount props carry that key whether or not you set it.

start_telnet(app_module, opts \\ [])

@spec start_telnet(
  module(),
  keyword()
) :: {:ok, pid()}

Starts a Telnet server hosting app_module, linked to the caller.

app_module is a module that does use Drafter.App. Always returns {:ok, pid} for the acceptor process, which is linked to the caller. The socket is opened inside that process, so a port already in use surfaces as an exit from the acceptor rather than an {:error, reason} return. Each client that connects gets its own session process.

Telnet carries no authentication or encryption; bind it only where that is acceptable.

Options

:port - TCP port. Default 2323. Bound on all interfaces.
:mode - :isolated (default) gives each client its own app state; :shared runs every client against one shared state.
:mount_props - map() handed to each session's mount/1. Default %{}.