Dashboard: per-host resource overview bar (0.20.0)

The dashboard resource bar (CPU cores, memory used/total, containers, Docker
version) is now rendered per host instead of once for the local host — each
host section (local + each agent) shows its own bar above its stacks table.

- agent_app.py: _system_info() now also returns mem_used (from meminfo
  available), alongside the cpu_cores/mem_total added in 0.19.0.
- Frontend: extracted a ResourceBar component used by the local section and each
  AgentDashboardSection; AgentSystem type gained mem_used.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

README.md

@@ -150,12 +150,14 @@ as intuitive as Dockge, as capable as Portainer for Compose workflows.
 
 ### Phase 17 — Multi-host dashboard
 
-- The dashboard now shows a **stacks-with-usage table per host** — the local host
-  plus a section for each registered agent (online dot, offline notice), with the
-  same CPU/memory meters and inline start/stop/restart as the local list.
+- The dashboard now shows, **per host** (local + each registered agent, online
+  dot / offline notice), a **resource overview bar** (CPU cores, memory
+  used/total, containers, Docker version) and a **stacks-with-usage table** with
+  the same CPU/memory meters and inline start/stop/restart.
 - New agent endpoint `/agent/stacks/stats` (proxied at
-  `/api/agents/{id}/stacks/stats`); `/agent/system` now also reports `cpu_cores`
-  and `mem_total` so remote meters have a host reference.
+  `/api/agents/{id}/stacks/stats`); `/agent/system` now also reports `cpu_cores`,
+  `mem_total` and `mem_used` so the remote resource bar and meters have a host
+  reference.
 
 ### Phase 16 — Volumes page (multi-host)
 

backend/agent_app.py

@@ -61,7 +61,7 @@ def _map_docker(exc: DockerError):
         raise HTTPException(status_code=code, detail=exc.detail or exc.error)
     raise exc  # falls through to the global 502 DockerError handler
 
-AGENT_VERSION = "0.19.0"
+AGENT_VERSION = "0.20.0"
 
 
 # --------------------------------------------------------------------------- #
@@ -159,16 +159,25 @@ def _hostname() -> str:
     return os.uname().nodename
 
 
-def _mem_total() -> int:
+def _mem_info() -> tuple[int, int]:
+    """Return (total_bytes, used_bytes) from meminfo (used = total - available)."""
     for base in (settings.HOST_PROC_PATH, "/proc"):
         try:
+            vals: dict[str, int] = {}
             with open(os.path.join(base, "meminfo"), "r", encoding="utf-8") as fh:
                 for line in fh:
-                    if line.startswith("MemTotal:"):
-                        return int(line.split()[1]) * 1024  # kB -> bytes
+                    parts = line.split(":")
+                    if len(parts) == 2 and parts[0] in ("MemTotal", "MemAvailable", "MemFree"):
+                        try:
+                            vals[parts[0]] = int(parts[1].split()[0]) * 1024  # kB -> bytes
+                        except ValueError:
+                            pass
+            total = vals.get("MemTotal", 0)
+            available = vals.get("MemAvailable", vals.get("MemFree", 0))
+            return total, max(total - available, 0)
         except OSError:
             continue
-    return 0
+    return 0, 0
 
 
 def _system_info() -> dict:
@@ -184,12 +193,14 @@ def _system_info() -> dict:
         total = info.get("Containers", 0)
     except DockerError as exc:
         docker_version = f"unavailable ({exc.error})"
+    mem_total, mem_used = _mem_info()
     return {
         "hostname": _hostname(),
         "docker_version": docker_version,
         "host_os": host_os,
         "cpu_cores": os.cpu_count() or 0,
-        "mem_total": _mem_total(),
+        "mem_total": mem_total,
+        "mem_used": mem_used,
         "containers_running": running,
         "containers_total": total,
     }

backend/main.py

@@ -55,7 +55,7 @@ async def lifespan(app: FastAPI):
     schedule_task.cancel()
 
 
-app = FastAPI(title="StackPilot", version="0.19.0", lifespan=lifespan)
+app = FastAPI(title="StackPilot", version="0.20.0", lifespan=lifespan)
 
 app.add_middleware(
     CORSMiddleware,

frontend/package.json

@@ -1,7 +1,7 @@
 {
   "name": "stackpilot-frontend",
   "private": true,
-  "version": "0.19.0",
+  "version": "0.20.0",
   "type": "module",
   "scripts": {
     "dev": "vite",

frontend/src/api/agents.ts

@@ -10,6 +10,7 @@ export interface AgentSystem {
   host_os: string;
   cpu_cores: number;
   mem_total: number;
+  mem_used: number;
   containers_running: number;
   containers_total: number;
 }

frontend/src/pages/Dashboard.tsx

@@ -51,33 +51,21 @@ export function Dashboard() {
         </Link>
       )}
 
-      {/* Local host resource bar */}
-      <div className="grid grid-cols-2 gap-4 md:grid-cols-4">
-        <Stat icon={<Cpu className="h-5 w-5" />} label="CPU cores" value={info.data?.cpu_cores ?? "—"} />
-        <Stat
-          icon={<MemoryStick className="h-5 w-5" />}
-          label="Memory"
-          value={
-            info.data
-              ? `${formatBytes(info.data.ram.used)} / ${formatBytes(info.data.ram.total)}`
-              : "—"
-          }
-        />
-        <Stat
-          icon={<Container className="h-5 w-5" />}
-          label="Containers"
-          value={info.data ? `${info.data.containers_running} / ${info.data.containers_total}` : "—"}
-        />
-        <Stat icon={<HardDrive className="h-5 w-5" />} label="Docker" value={info.data?.docker_version ?? "—"} />
-      </div>
-
-      {/* Local stacks */}
+      {/* Local host */}
       <section>
         {hasAgents ? (
           <HostHeader />
         ) : (
-          <h2 className="mb-3 text-sm font-semibold uppercase tracking-wide text-slate-500">Stacks</h2>
+          <h2 className="mb-3 text-sm font-semibold uppercase tracking-wide text-slate-500">This host</h2>
         )}
+        <ResourceBar
+          cpuCores={info.data?.cpu_cores ?? 0}
+          memUsed={info.data?.ram.used ?? 0}
+          memTotal={info.data?.ram.total ?? 0}
+          containersRunning={info.data?.containers_running ?? 0}
+          containersTotal={info.data?.containers_total ?? 0}
+          dockerVersion={info.data?.docker_version ?? ""}
+        />
         <StacksTable
           stacks={stacks.data}
           stats={stats.data}
@@ -175,6 +163,15 @@ function AgentDashboardSection({ agent, isAdmin }: { agent: Agent; isAdmin: bool
           </p>
         </Card>
       ) : (
+        <>
+        <ResourceBar
+          cpuCores={sys.data?.cpu_cores ?? 0}
+          memUsed={sys.data?.mem_used ?? 0}
+          memTotal={sys.data?.mem_total ?? 0}
+          containersRunning={sys.data?.containers_running ?? 0}
+          containersTotal={sys.data?.containers_total ?? 0}
+          dockerVersion={sys.data?.docker_version ?? ""}
+        />
         <StacksTable
           stacks={stacks.data}
           stats={stats.data}
@@ -189,6 +186,7 @@ function AgentDashboardSection({ agent, isAdmin }: { agent: Agent; isAdmin: bool
           onRestart={(id) => run("restart", "Restarting", id)}
           emptyText="No stacks on this host."
         />
+        </>
       )}
     </section>
   );
@@ -418,6 +416,39 @@ function Meter({
   );
 }
 
+function ResourceBar({
+  cpuCores,
+  memUsed,
+  memTotal,
+  containersRunning,
+  containersTotal,
+  dockerVersion,
+}: {
+  cpuCores: number;
+  memUsed: number;
+  memTotal: number;
+  containersRunning: number;
+  containersTotal: number;
+  dockerVersion: string;
+}) {
+  return (
+    <div className="mb-4 grid grid-cols-2 gap-4 md:grid-cols-4">
+      <Stat icon={<Cpu className="h-5 w-5" />} label="CPU cores" value={cpuCores || "—"} />
+      <Stat
+        icon={<MemoryStick className="h-5 w-5" />}
+        label="Memory"
+        value={memTotal ? `${formatBytes(memUsed)} / ${formatBytes(memTotal)}` : "—"}
+      />
+      <Stat
+        icon={<Container className="h-5 w-5" />}
+        label="Containers"
+        value={`${containersRunning} / ${containersTotal}`}
+      />
+      <Stat icon={<HardDrive className="h-5 w-5" />} label="Docker" value={dockerVersion || "—"} />
+    </div>
+  );
+}
+
 function Stat({
   icon,
   label,