Add cluster-aware APRS-IS status checking

Both /status and /status.json endpoints now show cluster-wide APRS-IS
connection status instead of just local node status.

Features:
- get_cluster_aprs_status() checks all nodes in cluster via RPC
- Returns status from any connected node (usually the leader)
- Shows cluster info: total nodes, connected nodes, leader node
- Graceful fallback to local status in non-clustered mode
- Enhanced status page UI with cluster information display

This ensures status pages accurately reflect the true APRS-IS
connection state across the entire cluster.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

lib/aprsme/cluster/leader_election.ex

@@ -22,6 +22,21 @@ defmodule Aprsme.Cluster.LeaderElection do
     GenServer.call(__MODULE__, :current_leader)
   end
 
+  @doc """
+  Gets APRS-IS status from across the entire cluster.
+  Returns the status from whichever node has an active connection.
+  """
+  def get_cluster_aprs_status do
+    cluster_enabled = Application.get_env(:aprsme, :cluster_enabled, false)
+
+    if cluster_enabled do
+      get_cluster_wide_status()
+    else
+      # Non-clustered mode - just return local status
+      Aprsme.Is.get_status()
+    end
+  end
+
   @impl true
   def init(_opts) do
     Logger.info("Starting leader election process")
@@ -179,6 +194,67 @@ defmodule Aprsme.Cluster.LeaderElection do
     end
   end
 
+  defp get_cluster_wide_status do
+    all_nodes = [node() | Node.list()]
+
+    # Check each node for APRS-IS connection status
+    connected_statuses =
+      all_nodes
+      |> Enum.map(&get_node_status/1)
+      |> Enum.filter(fn status -> status.connected end)
+
+    case connected_statuses do
+      [status | _] ->
+        # At least one node is connected - return its status
+        # Add cluster info to indicate this is cluster-wide status
+        Map.put(status, :cluster_info, %{
+          total_nodes: length(all_nodes),
+          connected_nodes: length(connected_statuses),
+          leader_node: get_leader_node_name()
+        })
+
+      [] ->
+        # No nodes are connected - return local status but mark as cluster-wide
+        local_status = Aprsme.Is.get_status()
+
+        Map.put(local_status, :cluster_info, %{
+          total_nodes: length(all_nodes),
+          connected_nodes: 0,
+          leader_node: get_leader_node_name()
+        })
+    end
+  end
+
+  defp get_node_status(node_name) do
+    if node_name == node() do
+      # Local node - call directly
+      Aprsme.Is.get_status()
+    else
+      # Remote node - use RPC
+      case :rpc.call(node_name, Aprsme.Is, :get_status, [], 5000) do
+        {:badrpc, _reason} ->
+          # Node unreachable - return disconnected status
+          %{connected: false, server: "unreachable", port: 0}
+
+        status when is_map(status) ->
+          status
+
+        _ ->
+          %{connected: false, server: "error", port: 0}
+      end
+    end
+  rescue
+    _error ->
+      %{connected: false, server: "error", port: 0}
+  end
+
+  defp get_leader_node_name do
+    case :global.whereis_name(@election_key) do
+      :undefined -> "none"
+      pid when is_pid(pid) -> pid |> node() |> to_string()
+    end
+  end
+
   defp notify_leadership_change(became_leader) do
     Phoenix.PubSub.broadcast(
       Aprsme.PubSub,

lib/aprsme_web/controllers/page_controller.ex

@@ -55,8 +55,8 @@ defmodule AprsmeWeb.PageController do
   end
 
   def status_json(conn, _params) do
-    # Get APRS-IS connection status
-    aprs_status = Aprsme.Is.get_status()
+    # Get cluster-wide APRS-IS connection status
+    aprs_status = Aprsme.Cluster.LeaderElection.get_cluster_aprs_status()
 
     # Get application version
     version = :aprsme |> Application.spec(:vsn) |> List.to_string()

lib/aprsme_web/live/status_live/index.ex

@@ -283,6 +283,49 @@ defmodule AprsmeWeb.StatusLive.Index do
               </div>
             </div>
           </div>
+          
+    <!-- Cluster Information (if available) -->
+          <%= if Map.has_key?(@aprs_status, :cluster_info) do %>
+            <div class="mb-8">
+              <h2 class="text-xl font-semibold mb-4">{gettext("Cluster Status")}</h2>
+              <div class="card bg-base-200">
+                <div class="card-body">
+                  <div class="grid grid-cols-1 md:grid-cols-3 gap-4">
+                    <div class="flex items-center">
+                      <span class="text-sm font-medium opacity-70 mr-2">{gettext("Total Nodes:")}</span>
+                      <span class="text-sm font-mono">{@aprs_status.cluster_info.total_nodes}</span>
+                    </div>
+
+                    <div class="flex items-center">
+                      <span class="text-sm font-medium opacity-70 mr-2">{gettext("Connected Nodes:")}</span>
+                      <span class="text-sm font-mono">{@aprs_status.cluster_info.connected_nodes}</span>
+                    </div>
+
+                    <div class="flex items-center">
+                      <span class="text-sm font-medium opacity-70 mr-2">{gettext("Leader Node:")}</span>
+                      <span class="text-sm font-mono">{@aprs_status.cluster_info.leader_node}</span>
+                    </div>
+                  </div>
+
+                  <div class="divider"></div>
+
+                  <div class="flex items-center">
+                    <span class="text-sm font-medium opacity-70 mr-2">{gettext("Cluster Mode:")}</span>
+                    <div class="badge badge-success gap-1">
+                      <div class="w-2 h-2 bg-current rounded-full"></div>
+                      {gettext("Enabled")}
+                    </div>
+                  </div>
+
+                  <p class="text-xs opacity-70 mt-2">
+                    {gettext(
+                      "Status is aggregated from all nodes in the cluster. Only the leader node maintains the APRS-IS connection."
+                    )}
+                  </p>
+                </div>
+              </div>
+            </div>
+          <% end %>
         </div>
       </div>
     </div>
@@ -292,7 +335,7 @@ defmodule AprsmeWeb.StatusLive.Index do
   # Private functions
 
   defp get_aprs_status do
-    Aprsme.Is.get_status()
+    Aprsme.Cluster.LeaderElection.get_cluster_aprs_status()
   rescue
     error ->
       require Logger