feat: poll actual firmware version and serial from SNMP

Enhance dynamic profile to poll OS definitions from SNMP:
- Add serial_number field to snmp_devices table
- Update Dynamic profile to query profile_os_definitions
- Poll SNMP OIDs for version and serial fields
- Display actual firmware version instead of profile name

For ePMP devices, this will now query:
- CAMBIUM-PMP80211-MIB::cambiumCurrentuImageVersion.0 for firmware
- CAMBIUM-PMP80211-MIB::cambiumEPMPMSN.0 for serial number

The Operating System field will now show actual version like
'Cambium 4.7.1' instead of 'Cambium epmp'.

lib/towerops/snmp/device.ex

@@ -26,6 +26,7 @@ defmodule Towerops.Snmp.Device do
     field :manufacturer, :string
     field :model, :string
     field :firmware_version, :string
+    field :serial_number, :string
 
     belongs_to :device, DeviceSchema
 
@@ -46,6 +47,7 @@ defmodule Towerops.Snmp.Device do
           manufacturer: String.t() | nil,
           model: String.t() | nil,
           firmware_version: String.t() | nil,
+          serial_number: String.t() | nil,
           device_id: Ecto.UUID.t(),
           device: NotLoaded.t() | Devices.t(),
           interfaces: NotLoaded.t() | [Interface.t()],
@@ -67,7 +69,8 @@ defmodule Towerops.Snmp.Device do
       :sys_location,
       :manufacturer,
       :model,
-      :firmware_version
+      :firmware_version,
+      :serial_number
     ])
     |> validate_required([:device_id])
     |> unique_constraint(:device_id)

lib/towerops/snmp/discovery.ex

@@ -253,13 +253,13 @@ defmodule Towerops.Snmp.Discovery do
 
   @spec build_device_info(Client.connection_opts(), system_info(), profile()) ::
           {:ok, device_info()}
-  defp build_device_info(_client_opts, system_info, {:dynamic, profile}) do
+  defp build_device_info(client_opts, system_info, {:dynamic, profile}) do
     # Use dynamic profile to identify device
-    identified_info = Dynamic.identify_device(profile, system_info)
+    identified_info = Dynamic.identify_device(profile, client_opts, system_info)
     {:ok, identified_info}
   rescue
-    _error ->
-      Logger.error("Failed to identify device with dynamic profile")
+    error ->
+      Logger.error("Failed to identify device with dynamic profile: #{inspect(error)}")
       {:ok, system_info}
   end
 

lib/towerops/snmp/profiles/dynamic.ex

@@ -17,17 +17,24 @@ defmodule Towerops.Snmp.Profiles.Dynamic do
   @doc """
   Identifies device using the database profile information.
   Returns manufacturer, model, and firmware info.
+
+  Polls SNMP OIDs from OS definitions to extract version and serial number.
   """
-  @spec identify_device(DeviceProfile.t(), Discovery.system_info()) :: Discovery.device_info()
-  def identify_device(profile, _system_info) do
+  @spec identify_device(DeviceProfile.t(), Client.connection_opts(), Discovery.system_info()) ::
+          Discovery.device_info()
+  def identify_device(profile, client_opts, _system_info) do
+    # Load profile with OS definitions
+    profile = DeviceProfiles.get_profile_with_associations(profile.os)
+
+    # Poll OS definitions for version, serial, etc.
+    os_data = poll_os_definitions(profile, client_opts)
+
     # Use profile metadata to build device info
     %{
       manufacturer: extract_manufacturer(profile),
       model: profile.text || profile.os,
-      # Use profile OS name as firmware_version for now
-      # TODO: Poll SNMP OIDs from profile_os_definitions to get actual version
-      firmware_version: profile.os,
-      serial_number: nil
+      firmware_version: os_data[:version] || profile.os,
+      serial_number: os_data[:serial]
     }
   end
 
@@ -69,6 +76,43 @@ defmodule Towerops.Snmp.Profiles.Dynamic do
 
   # Private functions
 
+  defp poll_os_definitions(profile, client_opts) do
+    if profile && profile.os_definitions && length(profile.os_definitions) > 0 do
+      Logger.debug("Polling #{length(profile.os_definitions)} OS definitions for #{profile.os}")
+
+      # Poll each OS definition and build a map
+      profile.os_definitions
+      |> Enum.map(fn os_def ->
+        field = String.to_atom(os_def.field)
+        value = poll_os_definition_oid(client_opts, os_def)
+        {field, value}
+      end)
+      |> Enum.reject(fn {_field, value} -> is_nil(value) end)
+      |> Map.new()
+    else
+      %{}
+    end
+  end
+
+  defp poll_os_definition_oid(client_opts, os_def) do
+    # Use the OID from the OS definition
+    oid = os_def.oid
+
+    if oid do
+      case Client.get(client_opts, oid) do
+        {:ok, value} when is_binary(value) ->
+          value
+
+        {:ok, value} ->
+          to_string(value)
+
+        {:error, reason} ->
+          Logger.debug("Failed to poll OS definition OID #{oid}: #{inspect(reason)}")
+          nil
+      end
+    end
+  end
+
   defp extract_manufacturer(%DeviceProfile{group: group}) when is_binary(group) do
     # Capitalize manufacturer from group (e.g., "cambium" -> "Cambium")
     String.capitalize(group)

priv/repo/migrations/20260118002432_add_serial_number_to_snmp_devices.exs

@@ -0,0 +1,9 @@
+defmodule Towerops.Repo.Migrations.AddSerialNumberToSnmpDevices do
+  use Ecto.Migration
+
+  def change do
+    alter table(:snmp_devices) do
+      add :serial_number, :string
+    end
+  end
+end