fix(docker): collapse Swarm view per-cluster so multi-manager doesn't duplicate

Swarm services/nodes are cluster-global (every manager's API returns the same
list), but each manager reports them independently (rows keyed by host_id) and
the Swarm page grouped by reporting manager — so two managers in one cluster
listed every service and node twice.

Group the reporting managers into swarms in the swarm() view (managers sharing
any node_id are the same cluster, via union-find over node-set intersection),
then dedup within each: one service per name and one node per node_id, keeping
the freshest. Render one section per swarm ("reported by N managers · names").
node_id is globally unique so node dedup is always safe; grouping by node
overlap also keeps it correct if two separate swarms are ever monitored.

View-layer only — no schema/agent change. The main per-host container page is
unaffected (those are genuinely distinct per-node tasks).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016Jg27rgypiW2efULXJDtMC

plugins/docker/routes.py

@@ -361,8 +361,12 @@ async def container_detail(host_id: str, name: str):
 async def swarm():
     """Swarm topology page: services with replica health, nodes, placement.
 
-    Swarm tables are manager-scoped (each manager reports its own view), so we
-    group by reporting host — usually one group for a single-manager cluster.
+    Swarm services/nodes are cluster-global — every manager's API returns the
+    same list — but each manager reports them independently (rows keyed by
+    host_id). So we group the reporting managers into swarms (managers that share
+    any node_id are the same cluster) and dedup within each: one row per service
+    (by name) and per node (by node_id), keeping the freshest. Without this, two
+    managers in one cluster list every service/node twice.
     """
     async with current_app.db_sessionmaker() as db:
         services = list((await db.execute(
@@ -374,42 +378,79 @@ async def swarm():
         )).scalars())
         hosts = await _host_map(db, {s.host_id for s in services} | {n.host_id for n in nodes})
 
-    # node_id → hostname per reporting host, so placement reads as names not ids.
-    node_names: dict[tuple[str, str], str] = {
-        (n.host_id, n.node_id): (n.hostname or n.node_id) for n in nodes
-    }
-
-    groups: dict[str, dict] = {}
-    for s in services:
-        g = groups.setdefault(s.host_id, {"services": [], "nodes": []})
-        placement = []
-        for p in (json.loads(s.placement_json) if s.placement_json else []):
-            nid = p.get("node_id", "")
-            placement.append({
-                "node": node_names.get((s.host_id, nid), nid[:12] or "?"),
-                "running": p.get("running", 0),
-            })
-        g["services"].append({
-            "name": s.service_name, "mode": s.mode,
-            "running": s.running, "desired": s.desired, "image": s.image,
-            "healthy": s.running >= s.desired and s.desired > 0,
-            "degraded": 0 < s.running < s.desired,
-            "down": s.running == 0 and s.desired > 0,
-            "placement": placement,
-        })
+    # ── Group reporting managers into swarms by shared node membership ──────────
+    manager_ids = {s.host_id for s in services} | {n.host_id for n in nodes}
+    nodes_by_mgr: dict[str, set[str]] = {}
     for n in nodes:
-        g = groups.setdefault(n.host_id, {"services": [], "nodes": []})
-        g["nodes"].append(n)
+        nodes_by_mgr.setdefault(n.host_id, set()).add(n.node_id)
 
-    host_groups = [
-        {"host_id": hid,
-         "host_name": hosts[hid].name if hid in hosts else hid,
-         "host": hosts.get(hid),
-         **g}
-        for hid, g in groups.items()
-    ]
-    host_groups.sort(key=lambda g: g["host_name"].lower())
-    return await render_template("docker/swarm.html", host_groups=host_groups)
+    parent = {m: m for m in manager_ids}
+
+    def _find(x: str) -> str:
+        while parent[x] != x:
+            parent[x] = parent[parent[x]]
+            x = parent[x]
+        return x
+
+    mgrs = list(manager_ids)
+    for i in range(len(mgrs)):
+        for j in range(i + 1, len(mgrs)):
+            a, b = mgrs[i], mgrs[j]
+            if nodes_by_mgr.get(a) and nodes_by_mgr.get(b) and (nodes_by_mgr[a] & nodes_by_mgr[b]):
+                parent[_find(a)] = _find(b)
+
+    swarm_members: dict[str, set[str]] = {}
+    for m in manager_ids:
+        swarm_members.setdefault(_find(m), set()).add(m)
+
+    # ── Dedup services (by name) + nodes (by node_id) within each swarm ─────────
+    swarms = []
+    for members in swarm_members.values():
+        svc_by_name: dict[str, DockerSwarmService] = {}
+        for s in services:
+            if s.host_id in members and (
+                s.service_name not in svc_by_name
+                or s.updated_at > svc_by_name[s.service_name].updated_at
+            ):
+                svc_by_name[s.service_name] = s
+        node_by_id: dict[str, DockerSwarmNode] = {}
+        for n in nodes:
+            if n.host_id in members and (
+                n.node_id not in node_by_id
+                or n.updated_at > node_by_id[n.node_id].updated_at
+            ):
+                node_by_id[n.node_id] = n
+
+        node_names = {nid: (nrow.hostname or nid) for nid, nrow in node_by_id.items()}
+        svc_dicts = []
+        for s in sorted(svc_by_name.values(), key=lambda s: s.service_name):
+            placement = []
+            for p in (json.loads(s.placement_json) if s.placement_json else []):
+                nid = p.get("node_id", "")
+                placement.append({
+                    "node": node_names.get(nid, nid[:12] or "?"),
+                    "running": p.get("running", 0),
+                })
+            svc_dicts.append({
+                "name": s.service_name, "mode": s.mode,
+                "running": s.running, "desired": s.desired, "image": s.image,
+                "healthy": s.running >= s.desired and s.desired > 0,
+                "degraded": 0 < s.running < s.desired,
+                "down": s.running == 0 and s.desired > 0,
+                "placement": placement,
+            })
+        node_rows = sorted(
+            node_by_id.values(), key=lambda n: (n.role, (n.hostname or n.node_id).lower())
+        )
+        manager_names = sorted(hosts[m].name if m in hosts else m for m in members)
+        swarms.append({
+            "managers": manager_names,
+            "services": svc_dicts,
+            "nodes": node_rows,
+        })
+
+    swarms.sort(key=lambda g: g["managers"][0].lower() if g["managers"] else "")
+    return await render_template("docker/swarm.html", swarms=swarms)
 
 
 @docker_bp.get("/disk")

plugins/docker/templates/docker/swarm.html

@@ -7,12 +7,14 @@
 
 <h1 class="page-title" style="margin-bottom:1.5rem;">Swarm</h1>
 
-{% if host_groups %}
-{% for g in host_groups %}
+{% if swarms %}
+{% for g in swarms %}
 <div style="margin-bottom:2rem;">
-  <div style="display:flex;align-items:baseline;gap:0.6rem;margin-bottom:0.75rem;">
-    <span style="font-weight:600;font-size:0.95rem;">{{ g.host_name }}</span>
-    <span style="font-size:0.78rem;color:var(--text-muted);">manager view</span>
+  <div style="display:flex;align-items:baseline;gap:0.6rem;margin-bottom:0.75rem;flex-wrap:wrap;">
+    <span style="font-weight:600;font-size:0.95rem;">Swarm</span>
+    <span style="font-size:0.78rem;color:var(--text-muted);">
+      reported by {{ g.managers | length }} manager{{ 's' if g.managers | length != 1 }} · {{ g.managers | join(", ") }}
+    </span>
   </div>
 
   {# ── Services ─────────────────────────────────────────────────────────── #}
@@ -39,7 +41,7 @@
           </td>
         </tr>
         {% else %}
-        <tr><td colspan="5" style="color:var(--text-muted);font-size:0.85rem;text-align:center;padding:1.5rem;">No services on this manager.</td></tr>
+        <tr><td colspan="5" style="color:var(--text-muted);font-size:0.85rem;text-align:center;padding:1.5rem;">No services in this swarm.</td></tr>
         {% endfor %}
       </tbody>
     </table>