Use DeviceLink for module namespacing

And add some specs and docs

Author: joshk

lib/nerves_hub/rpc/device_auth.ex renamed to lib/nerves_hub/device_link/connections.ex

@@ -1,8 +1,10 @@
-defmodule NervesHub.RPC.DeviceAuth do
-  @moduledoc false
+defmodule NervesHub.DeviceLink.Connections do
+  @moduledoc """
+  Functions for connecting devices, including the reporting of connection availability.
+  """
 
   alias NervesHub.Devices
-  alias NervesHub.Devices.Connections
+  alias NervesHub.Devices.Connections, as: DeviceConnections
   alias NervesHub.Devices.DeviceConnection
   alias NervesHub.Devices.Device
   alias NervesHub.Products
@@ -13,6 +15,12 @@ defmodule NervesHub.RPC.DeviceAuth do
   # Default 90 seconds max age for the signature
   @default_max_hmac_age 90
 
+  @type auth() :: {:ssl_certs, any()} | {:shared_secrets, list()}
+  @type connection_id() :: binary()
+
+  @spec connect_device(auth()) :: {:ok, {connection_id(), Device.t()}} | {:error, :invalid_auth}
+  def connect_device(auth)
+
   def connect_device({:ssl_certs, ssl_cert}) do
     X509.Certificate.from_der!(ssl_cert)
     |> Devices.get_device_by_x509()
@@ -52,6 +60,9 @@ defmodule NervesHub.RPC.DeviceAuth do
     end
   end
 
+  @spec disconnect_device(any(), Device.t(), connection_id()) :: :ok
+  def disconnect_device(reason, device, reference_id)
+
   def disconnect_device({:error, {:shutdown, :disconnected}}, device, reference_id) do
     :telemetry.execute([:nerves_hub, :devices, :duplicate_connection], %{count: 1}, %{
       ref_id: reference_id,
@@ -67,13 +78,18 @@ defmodule NervesHub.RPC.DeviceAuth do
       identifier: device.identifier
     })
 
-    {:ok, _device_connection} = Connections.device_disconnected(reference_id)
+    {:ok, _device_connection} = DeviceConnections.device_disconnected(reference_id)
 
     Tracker.offline(device)
 
     :ok
   end
 
+  @spec device_heartbeat(connection_id()) :: :ok
+  def device_heartbeat(reference_id) do
+    DeviceConnections.device_heartbeat(reference_id)
+  end
+
   defp on_connect(%Device{status: :registered} = device) do
     Devices.set_as_provisioned!(device)
     |> on_connect()
@@ -89,7 +105,7 @@ defmodule NervesHub.RPC.DeviceAuth do
       %{}
     )
 
-    {:ok, %DeviceConnection{id: connection_id}} = Connections.device_connected(device.id)
+    {:ok, %DeviceConnection{id: connection_id}} = DeviceConnections.device_connected(device.id)
 
     :telemetry.execute([:nerves_hub, :devices, :connect], %{count: 1}, %{
       ref_id: connection_id,

lib/nerves_hub_web/channels/device_socket.ex

@@ -4,9 +4,7 @@ defmodule NervesHubWeb.DeviceSocket do
 
   require Logger
 
-  alias NervesHub.Devices.Connections
-
-  alias NervesHub.RPC.DeviceAuth
+  alias NervesHub.DeviceLink.Connections
 
   channel("console", NervesHubWeb.ConsoleChannel)
   channel("device", NervesHubWeb.DeviceChannel)
@@ -18,7 +16,7 @@ defmodule NervesHubWeb.DeviceSocket do
   @decorate with_span("Channels.DeviceSocket.terminate")
   def terminate(reason, {_channels_info, socket} = state) do
     %{assigns: %{device: device, reference_id: reference_id}} = socket
-    DeviceAuth.disconnect_device(reason, device, reference_id)
+    Connections.disconnect_device(reason, device, reference_id)
     super(reason, state)
   end
 
@@ -58,10 +56,10 @@ defmodule NervesHubWeb.DeviceSocket do
 
   # Used by Devices connecting with SSL certificates
   @impl Phoenix.Socket
-  @decorate with_span("Channels.DeviceSocket.connect")
+  @decorate with_span("Channels.DeviceSocket.connect#ssl_cert")
   def connect(_params, socket, %{peer_data: %{ssl_cert: ssl_cert}})
       when not is_nil(ssl_cert) do
-    case DeviceAuth.connect_device({:ssl_certs, ssl_cert}) do
+    case Connections.connect_device({:ssl_certs, ssl_cert}) do
       {:ok, ref_and_device} ->
         socket_and_assigns(socket, ref_and_device)
 
@@ -71,10 +69,11 @@ defmodule NervesHubWeb.DeviceSocket do
   end
 
   # Used by Devices connecting with HMAC Shared Secrets
-  @decorate with_span("Channels.DeviceSocket.connect")
+  @impl Phoenix.Socket
+  @decorate with_span("Channels.DeviceSocket.connect#shared_secrets")
   def connect(_params, socket, %{x_headers: x_headers})
       when is_list(x_headers) and length(x_headers) > 0 do
-    case DeviceAuth.connect_device({:shared_secrets, x_headers}) do
+    case Connections.connect_device({:shared_secrets, x_headers}) do
       {:ok, ref_and_device} ->
         socket_and_assigns(socket, ref_and_device)
 
@@ -83,6 +82,7 @@ defmodule NervesHubWeb.DeviceSocket do
     end
   end
 
+  @impl Phoenix.Socket
   def connect(_params, _socket, _connect_info) do
     {:error, :no_auth}
   end