CHANGELOG.md

@@ -5,6 +5,50 @@ All notable changes to Terra-View will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+
+SLM live monitoring — fan-out feed + cache-first reads.  Targets **0.14.0**.  The throughline: the NL-43 allows exactly **one** TCP connection at a time, so every page that opened its own device stream (or sent its own `Measure?`/DOD on load) was competing for that single connection — a second viewer saw nothing, and dashboard loads stole polling resolution from the live feed.  This release moves Terra-View entirely onto SLMM's shared, cached monitoring: one DOD poll loop per device, fanned out to all viewers; dashboards read SLMM's cache (a DB read on SLMM's side) instead of touching the device; and the live panels populate instantly from cache on open, upgrading to the live WS only on demand.  Paired with the SLMM-side work (adaptive poll rate, unreachable backoff, device-offline alert) on SLMM branch `dev`.
+
+### Added
+
+- **Fan-out `/monitor` feed consumption.**  The unit live view (`partials/slm_live_view.html`) and the dashboard live tile (`sound_level_meters.html`) now subscribe to SLMM's shared per-device monitor over `WS /api/slmm/{unit}/monitor` instead of each opening its own device stream.  Any number of clients attach without each consuming the NL-43's single connection — the "second viewer sees nothing" contention is gone.  A WS proxy handler for `/monitor` was added to `backend/routers/slmm.py`.
+- **L1/L10 percentile lines + cards.**  Both the per-unit live chart and the dashboard card chart now plot L1 (purple) and L10 (orange) alongside Lp/Leq, and the KPI cards show L1/L10.  Sourced from the DOD feed's `ln1`/`ln2` (DRD streaming can't carry percentiles, DOD can).  Missing/`-.-` values leave a gap rather than dropping the line to 0.
+- **Live-chart backfill on open.**  Charts seed from SLMM's downsampled DOD trail (`GET /api/slmm/{unit}/history?hours=2`) so a viewer sees recent trend immediately instead of a blank chart that fills one point per second.
+- **Live Measurements panel auto-populates from cache.**  Opening the dashboard panel fills the KPI cards from cached `/status` and backfills the chart from `/history` — pure cache reads, no device hit.  Shows a measuring badge (● Measuring / ■ Stopped) and a freshness stamp ("as of 3:48 PM (10s ago)", amber + "cached" when stale).  Re-polls the cache every 15s while open; **Start Live Stream** upgrades to the live WS and no longer wipes the backfilled trail (chart point cap raised 60 → 600).
+- **Refresh buttons** — one per device-list row, one in the panel header.  On-demand, user-initiated single device read via `GET /api/slmm/{unit}/live` (which also refreshes SLMM's cache), with a spinner + success/error toast, then reloads the device list.
+- **Per-unit live-monitoring (keepalive) toggle on `/admin/slmm`** — turns a device's server-side keepalive feed on/off (`POST /monitor/start|stop`), so alerting can keep a device's feed running with no browser attached.
+
+### Changed
+
+- **Dashboard device list + command center read SLMM's cache, not the device.**  `slm_dashboard.py`'s `get_slm_units` pulls each unit's cached status from SLMM's `/roster` (one call, a SLMM DB read) for the badge + freshness; the command-center `get_live_view` reads cached `/status` instead of sending `Measure?` + a fresh DOD on every load.  This stops dashboard loads from stealing the device's single connection from the live monitor.  The elapsed-measurement timer still works because `measurement_start_time` is now included in the cached `/status` response.
+- **Device-list freshness reflects real monitoring.**  The "Last check" line now uses SLMM's cached `last_seen` (which the monitor advances on every successful poll) via `unit.cache_last_seen`, instead of the `slm_last_check` roster field the monitor never updates.  The status badge also treats `Measure` as Measuring, matching the panel and SLMM's cache.
+- **Status badge relocated** to the card's bottom meta row (next to "Last check"), off the top-right corner where it collided with the chart/gear/refresh action icons.
+
+### Fixed
+
+- **Deploy/bench threw `can't access property "dispatchEvent", e is null`.**  `toggleSLMDeployed()` and the save-config path called `htmx.trigger('#slm-list', 'load')` guarded only by `typeof htmx !== 'undefined'`; no page has a `#slm-list`, so htmx resolved null and called `null.dispatchEvent(...)`.  The deploy POST had already succeeded, so the operator saw both the green success **and** a red error.  Both call sites now guard on the element existing (`slm_settings_modal.html`).
+- **Monitor WS proxy leaked `CancelledError` / "task exception never retrieved"** on stream stop — the cleanup awaited pending tasks but only caught `Exception`, missing `CancelledError` (a `BaseException`).
+- **"No recent check-in" shown even on an actively-monitored device** — the row read the stale `slm_last_check` roster field instead of SLMM's live cache (see Changed).
+- **L1/L10 KPI cards populated but the chart drew no L1/L10 lines** — the card chart only had Lp + Leq datasets.
+
+### Upgrade Notes
+
+Requires the **matching SLMM build (branch `dev`)** — Terra-View now depends on SLMM's fan-out `/monitor` feed, `/history` trail, `/status` carrying `ln1`/`ln2` + `measurement_start_time`, cached `/roster` status, and the `monitor_enabled` keepalive flag.
+
+```bash
+# SLMM (branch dev) — REBUILD + MIGRATE (or you'll get `no such column: nl43_status.ln1` 500s)
+cd /home/serversdown/slmm && docker compose build slmm && docker compose up -d slmm
+docker exec terra-view-slmm-1 python3 migrate_add_ln_percentiles.py
+docker exec terra-view-slmm-1 python3 migrate_add_monitor_enabled.py
+
+# Terra-View — NO migration; templates are baked into the image, so rebuild (don't just restart)
+cd /home/serversdown/terra-view && docker compose build terra-view && docker compose up -d terra-view
+```
+
+The two builds must ship **together**.  Note the `docker-compose.yml` container was renamed for clarity (now `terra-view-terra-view-1`) — adjust any `docker exec` scripts that referenced the old name.
+
+---
+
 ## [0.13.3] - 2026-06-05
 
 Calibration sync from SFM events.  Closes the manual data-entry loop on calibration dates — Terra-View now pulls `device.calibration_date` from each seismograph's most recent event sidecar once a day and updates `RosterUnit.last_calibrated` when the device reports something fresher than what's stored.  Manual edits still win when they're newer than the latest event; a fresh event arriving later supersedes the manual edit.  Adds a "Sync now" button under Settings → Advanced → Calibration Defaults for on-demand runs, and a `docs/ROADMAP.md` to track in-flight + deferred work.

backend/routers/slm_dashboard.py

@@ -91,29 +91,43 @@ async def get_slm_units(
 
     one_hour_ago = datetime.utcnow() - timedelta(hours=1)
     for unit in units:
+        # Legacy default from the roster field; refined from SLMM's cached status below.
         unit.is_recent = bool(unit.slm_last_check and unit.slm_last_check > one_hour_ago)
+        unit.measurement_state = None
+        unit.cache_last_seen = None  # SLMM cache last_seen (real monitoring freshness)
 
     if include_measurement:
-        async def fetch_measurement_state(client: httpx.AsyncClient, unit_id: str) -> str | None:
+        # SLMM's /roster carries each unit's CACHED status (last_seen,
+        # measurement_state) from NL43Status — a DB read on SLMM's side, NOT a device
+        # call. The live monitor refreshes that cache ~every 1.3s, so this reflects
+        # real monitoring without sending Measure? to the device (which the old
+        # /measurement-state did) and competing with DOD polling. One call covers all.
+        slmm_status = {}
         try:
-                response = await client.get(f"{SLMM_BASE_URL}/api/nl43/{unit_id}/measurement-state")
-                if response.status_code == 200:
-                    return response.json().get("measurement_state")
-            except Exception:
-                return None
-            return None
-
-        deployed_units = [unit for unit in units if unit.deployed and not unit.retired]
-        if deployed_units:
             async with httpx.AsyncClient(timeout=3.0) as client:
-                tasks = [fetch_measurement_state(client, unit.id) for unit in deployed_units]
+                r = await client.get(f"{SLMM_BASE_URL}/api/nl43/roster")
-                results = await asyncio.gather(*tasks, return_exceptions=True)
+                if r.status_code == 200:
+                    for dev in (r.json().get("devices") or []):
+                        slmm_status[dev.get("unit_id")] = dev.get("status") or {}
+        except Exception:
+            slmm_status = {}
 
-            for unit, state in zip(deployed_units, results):
+        # "Recent" = the monitor has a fresh successful read. last_seen only advances
-                if isinstance(state, Exception):
+        # on a successful poll, so staleness == the device isn't being reached.
-                    unit.measurement_state = None
+        recent_cutoff = datetime.utcnow() - timedelta(minutes=5)
-                else:
+        for unit in units:
-                    unit.measurement_state = state
+            st = slmm_status.get(unit.id)
+            if not st:
+                continue
+            unit.measurement_state = st.get("measurement_state")
+            last_seen = st.get("last_seen")
+            if last_seen:
+                try:
+                    ls = datetime.fromisoformat(last_seen.replace("Z", ""))
+                    unit.is_recent = ls > recent_cutoff
+                    unit.cache_last_seen = ls  # the real freshness the monitor updates
+                except Exception:
+                    pass
 
     return templates.TemplateResponse("partials/slm_device_list.html", {
         "request": request,
@@ -157,25 +171,18 @@ async def get_live_view(request: Request, unit_id: str, db: Session = Depends(ge
     is_measuring = False
 
     try:
-        async with httpx.AsyncClient(timeout=10.0) as client:
+        # Read SLMM's CACHED status (NL43Status) — no device call. The live monitor
-            # Get measurement state
+        # keeps it fresh (~1.3s) and the live-stream WS provides ongoing updates, so we
-            state_response = await client.get(
+        # no longer fire Measure? + a fresh DOD read at the device on every command-
-                f"{SLMM_BASE_URL}/api/nl43/{unit_id}/measurement-state"
+        # center load (which competed with DOD polling for the single connection).
-            )
+        async with httpx.AsyncClient(timeout=5.0) as client:
-            if state_response.status_code == 200:
+            r = await client.get(f"{SLMM_BASE_URL}/api/nl43/{unit_id}/status")
-                state_data = state_response.json()
+            if r.status_code == 200:
-                measurement_state = state_data.get("measurement_state", "Unknown")
+                current_status = r.json().get("data", {})
-                is_measuring = state_data.get("is_measuring", False)
+                measurement_state = current_status.get("measurement_state")
-
+                is_measuring = measurement_state in ("Start", "Measure")
-            # Get live status (measurement_start_time is already stored in SLMM database)
-            status_response = await client.get(
-                f"{SLMM_BASE_URL}/api/nl43/{unit_id}/live"
-            )
-            if status_response.status_code == 200:
-                status_data = status_response.json()
-                current_status = status_data.get("data", {})
     except Exception as e:
-        logger.error(f"Failed to get status for {unit_id}: {e}")
+        logger.error(f"Failed to get cached status for {unit_id}: {e}")
 
     return templates.TemplateResponse("partials/slm_live_view.html", {
         "request": request,

backend/routers/slmm.py

@@ -231,6 +231,76 @@ async def proxy_websocket_live(websocket: WebSocket, unit_id: str):
         logger.info(f"WebSocket proxy closed for {unit_id} (live)")
 
 
+@router.websocket("/{unit_id}/monitor")
+async def proxy_websocket_monitor(websocket: WebSocket, unit_id: str):
+    """
+    Proxy WebSocket connections to SLMM's /monitor (fan-out DOD feed).
+
+    This is the shared ~1Hz DOD feed: many clients subscribe to one device feed
+    (no single-connection contention) and it carries L1/L10 (which the DRD
+    /stream cannot). Preferred over /stream for the live view.
+    """
+    await websocket.accept()
+    logger.info(f"WebSocket accepted for SLMM unit {unit_id} (monitor)")
+
+    target_ws_url = f"{SLMM_WS_BASE_URL}/api/nl43/{unit_id}/monitor"
+    backend_ws = None
+
+    try:
+        backend_ws = await websockets.connect(target_ws_url)
+        logger.info(f"Connected to SLMM monitor feed for {unit_id}")
+
+        async def forward_to_client():
+            """Backend monitor frames -> browser."""
+            async for message in backend_ws:
+                await websocket.send_text(message)
+
+        async def watch_client():
+            """Drain client frames; raises WebSocketDisconnect on close so we can
+            tear the pair down (the monitor feed is server->client only)."""
+            while True:
+                await websocket.receive_text()
+
+        # When EITHER side ends (browser disconnects or backend closes), cancel the
+        # other immediately — avoids sending into a closed socket (the
+        # "Unexpected ASGI message after close" race that asyncio.gather leaves open).
+        tasks = [asyncio.ensure_future(forward_to_client()),
+                 asyncio.ensure_future(watch_client())]
+        done, pending = await asyncio.wait(tasks, return_when=asyncio.FIRST_COMPLETED)
+        for t in pending:
+            t.cancel()
+        # Await ALL tasks (the done one AND the cancelled one) and swallow both
+        # the expected WebSocketDisconnect and CancelledError. CancelledError is a
+        # BaseException, so a bare `except Exception` misses it — that's what leaked
+        # the traceback on stop; and awaiting only `pending` left the done task's
+        # exception unretrieved.
+        for t in tasks:
+            try:
+                await t
+            except (asyncio.CancelledError, Exception):
+                pass
+
+    except websockets.exceptions.WebSocketException as e:
+        logger.error(f"WebSocket error connecting to SLMM monitor for {unit_id}: {e}")
+        try:
+            await websocket.send_json({"error": "Failed to connect to SLMM monitor", "detail": str(e)})
+        except Exception:
+            pass
+    except Exception as e:
+        logger.error(f"Unexpected error in monitor proxy for {unit_id}: {e}")
+    finally:
+        if backend_ws:
+            try:
+                await backend_ws.close()
+            except Exception:
+                pass
+        try:
+            await websocket.close()
+        except Exception:
+            pass
+        logger.info(f"WebSocket monitor proxy closed for {unit_id}")
+
+
 # HTTP catch-all route MUST come after specific routes (including WebSocket routes)
 @router.api_route("/{path:path}", methods=["GET", "POST", "PUT", "DELETE", "PATCH"])
 async def proxy_to_slmm(path: str, request: Request):

docker-compose.yml

@@ -1,6 +1,6 @@
 services:
 
-  terra-view:
+  web-app:
     build: .
     ports:
       - "8001:8001"

templates/admin_slmm.html

@@ -42,6 +42,18 @@
     </div>
 </div>
 
+<!-- Live Monitoring (keepalive) -->
+<div class="rounded-xl bg-white dark:bg-slate-800 shadow-lg p-4 mb-6">
+    <h2 class="text-sm font-semibold text-gray-700 dark:text-gray-300 uppercase tracking-wider mb-1">Live Monitoring (keepalive)</h2>
+    <p class="text-xs text-gray-500 dark:text-gray-400 mb-3">
+        Keepalive runs the 1&nbsp;Hz DOD feed 24/7 (even with no viewer), which powers the live-chart
+        trail and continuous threshold alerts. Toggling persists and survives restarts.
+    </p>
+    <div id="monitor-list" class="text-sm">
+        <p class="text-gray-500 dark:text-gray-400">Loading…</p>
+    </div>
+</div>
+
 <!-- Raw API tester -->
 <div class="rounded-xl bg-white dark:bg-slate-800 shadow-lg p-4 mb-6">
     <h2 class="text-sm font-semibold text-gray-700 dark:text-gray-300 uppercase tracking-wider mb-3">Raw API Tester</h2>
@@ -132,7 +144,60 @@ async function sendRaw() {
     }
 }
 
+async function loadMonitors() {
+    const el = document.getElementById('monitor-list');
+    try {
+        const r = await fetch('/api/slmm/roster');
+        if (!r.ok) throw new Error('HTTP ' + r.status);
+        const d = await r.json();
+        const devices = d.devices || [];
+        if (!devices.length) {
+            el.innerHTML = '<p class="text-gray-500 dark:text-gray-400">No devices configured.</p>';
+            return;
+        }
+        el.innerHTML = devices.map(dev => {
+            const on = !!dev.monitor_enabled;
+            const reach = dev.status ? dev.status.is_reachable : null;
+            const reachDot = reach === false
+                ? '<span class="w-2 h-2 rounded-full bg-red-500 inline-block" title="unreachable"></span>'
+                : '<span class="w-2 h-2 rounded-full bg-green-500 inline-block" title="reachable"></span>';
+            return `
+            <div class="flex items-center justify-between border-b border-gray-100 dark:border-gray-700 py-2">
+                <div class="flex items-center gap-2">
+                    ${reachDot}
+                    <span class="font-mono text-gray-900 dark:text-white">${_esc(dev.unit_id)}</span>
+                    <span class="text-xs text-gray-500 dark:text-gray-400">${_esc(dev.host)}:${_esc(dev.tcp_port)}</span>
+                </div>
+                <div class="flex items-center gap-3">
+                    <span class="text-xs font-medium px-2 py-0.5 rounded ${on
+                        ? 'bg-green-100 text-green-700 dark:bg-green-900/40 dark:text-green-300'
+                        : 'bg-gray-100 text-gray-600 dark:bg-slate-700 dark:text-gray-400'}">${on ? '24/7 ON' : 'OFF'}</span>
+                    <button onclick="toggleMonitor('${_esc(dev.unit_id)}', ${!on})"
+                            class="px-3 py-1 text-xs rounded text-white ${on
+                                ? 'bg-red-600 hover:bg-red-700' : 'bg-seismo-orange hover:bg-orange-600'}">
+                        ${on ? 'Disable' : 'Enable'}
+                    </button>
+                </div>
+            </div>`;
+        }).join('');
+    } catch (e) {
+        el.innerHTML = `<p class="text-red-600 dark:text-red-400">Failed to load devices: ${_esc(e.message)}</p>`;
+    }
+}
+
+async function toggleMonitor(unitId, enable) {
+    const action = enable ? 'start' : 'stop';
+    try {
+        const r = await fetch(`/api/slmm/${encodeURIComponent(unitId)}/monitor/${action}`, { method: 'POST' });
+        if (!r.ok) throw new Error('HTTP ' + r.status);
+        await loadMonitors();
+    } catch (e) {
+        alert('Toggle failed: ' + e.message);
+    }
+}
+
 loadSlmmOverview();
-setInterval(loadSlmmOverview, 30000);
+loadMonitors();
+setInterval(() => { loadSlmmOverview(); loadMonitors(); }, 30000);
 </script>
 {% endblock %}

templates/partials/slm_device_list.html

@@ -2,7 +2,14 @@
 {% if units %}
     {% for unit in units %}
     <div class="bg-gray-50 dark:bg-gray-800 rounded-lg p-4 border border-transparent hover:border-seismo-orange transition-colors relative">
-        <div class="absolute top-3 right-3 flex gap-2">
+        <div class="absolute top-3 right-3 flex gap-2 z-10">
+            <button onclick="event.preventDefault(); event.stopPropagation(); refreshSlmUnit('{{ unit.id }}', this);"
+                    class="text-gray-500 hover:text-seismo-orange dark:text-gray-400 dark:hover:text-seismo-orange"
+                    title="Refresh {{ unit.id }} from device">
+                <svg class="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                    <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M4 4v5h.582m15.356 2A8.001 8.001 0 004.582 9m0 0H9m11 11v-5h-.581m0 0a8.003 8.003 0 01-15.357-2m15.357 2H15"></path>
+                </svg>
+            </button>
             <button onclick="event.preventDefault(); event.stopPropagation(); showLiveChart('{{ unit.id }}');"
                     class="text-gray-500 hover:text-seismo-orange dark:text-gray-400 dark:hover:text-seismo-orange"
                     title="View live chart">
@@ -20,9 +27,8 @@
             </button>
         </div>
 
-        <a href="/slm/{{ unit.id }}" class="block">
+        <a href="/slm/{{ unit.id }}" class="block pr-24">
-            <div class="flex items-start justify-between gap-4">
+            <div class="min-w-0">
-                <div class="min-w-0 flex-1">
                 <div class="flex items-center gap-2">
                     <span class="font-semibold text-gray-900 dark:text-white">{{ unit.id }}</span>
                     {% if unit.slm_model %}
@@ -36,25 +42,29 @@
                 {% endif %}
             </div>
 
+            <!-- Status badge + last-check on one line (moved off the top-right so it
+                 no longer collides with the refresh/chart/gear action icons). -->
+            <div class="mt-2 flex items-center gap-2 flex-wrap">
                 {% if unit.retired %}
-                    <span class="shrink-0 px-2 py-1 text-xs font-medium bg-gray-200 text-gray-700 dark:bg-gray-700 dark:text-gray-300 rounded-full">Retired</span>
+                    <span class="px-2 py-0.5 text-xs font-medium bg-gray-200 text-gray-700 dark:bg-gray-700 dark:text-gray-300 rounded-full">Retired</span>
                 {% elif not unit.deployed %}
-                    <span class="shrink-0 px-2 py-1 text-xs font-medium bg-amber-100 text-amber-800 dark:bg-amber-900/30 dark:text-amber-300 rounded-full">Benched</span>
+                    <span class="px-2 py-0.5 text-xs font-medium bg-amber-100 text-amber-800 dark:bg-amber-900/30 dark:text-amber-300 rounded-full">Benched</span>
-                {% elif unit.measurement_state == "Start" %}
+                {% elif unit.measurement_state in ["Start", "Measure"] %}
-                    <span class="shrink-0 px-2 py-1 text-xs font-medium bg-green-100 text-green-800 dark:bg-green-900/30 dark:text-green-300 rounded-full">Measuring</span>
+                    <span class="px-2 py-0.5 text-xs font-medium bg-green-100 text-green-800 dark:bg-green-900/30 dark:text-green-300 rounded-full">Measuring</span>
                 {% elif unit.is_recent %}
-                    <span class="shrink-0 px-2 py-1 text-xs font-medium bg-blue-100 text-blue-800 dark:bg-blue-900/30 dark:text-blue-300 rounded-full">Active</span>
+                    <span class="px-2 py-0.5 text-xs font-medium bg-blue-100 text-blue-800 dark:bg-blue-900/30 dark:text-blue-300 rounded-full">Active</span>
                 {% else %}
-                    <span class="shrink-0 px-2 py-1 text-xs font-medium bg-yellow-100 text-yellow-800 dark:bg-yellow-900/30 dark:text-yellow-300 rounded-full">Idle</span>
+                    <span class="px-2 py-0.5 text-xs font-medium bg-yellow-100 text-yellow-800 dark:bg-yellow-900/30 dark:text-yellow-300 rounded-full">Idle</span>
                 {% endif %}
-            </div>
+                <span class="text-xs text-gray-500 dark:text-gray-400">
-
+                    {% if unit.cache_last_seen %}
-            <div class="mt-2 text-xs text-gray-500 dark:text-gray-400">
+                        Last check: {{ unit.cache_last_seen|local_datetime }}
-                {% if unit.slm_last_check %}
+                    {% elif unit.slm_last_check %}
                         Last check: {{ unit.slm_last_check|local_datetime }}
                     {% else %}
                         No recent check-in
                     {% endif %}
+                </span>
             </div>
         </a>
     </div>

templates/partials/slm_live_view.html

@@ -143,6 +143,8 @@
                 </svg>
                 Stop Live Stream
             </button>
+
+            <span id="live-feed-status" class="ml-3 self-center" style="display: none;"></span>
         </div>
     </div>
 
@@ -432,6 +434,24 @@ function initializeChart() {
                 tension: 0.3,
                 borderWidth: 2,
                 pointRadius: 0
+            },
+            {
+                label: 'L1',
+                data: [],
+                borderColor: 'rgb(139, 92, 246)',
+                backgroundColor: 'rgba(139, 92, 246, 0.1)',
+                tension: 0.3,
+                borderWidth: 2,
+                pointRadius: 0
+            },
+            {
+                label: 'L10',
+                data: [],
+                borderColor: 'rgb(245, 158, 11)',
+                backgroundColor: 'rgba(245, 158, 11, 0.1)',
+                tension: 0.3,
+                borderWidth: 2,
+                pointRadius: 0
             }
         ]
     },
@@ -493,7 +513,37 @@ if (typeof window.currentWebSocket === 'undefined') {
     window.currentWebSocket = null;
 }
 
-function initLiveDataStream(unitId) {
+// Backfill the chart with the recent DOD trail so it opens with context.
+async function backfillChart(unitId) {
+    try {
+        const r = await fetch(`/api/slmm/${encodeURIComponent(unitId)}/history?hours=2`);
+        if (!r.ok) return;
+        const d = await r.json();
+        const readings = d.readings || [];
+        if (!window.chartData) return;
+        for (const row of readings) {
+            // Trail timestamps are naive UTC; append 'Z' so they convert to local
+            // consistently with the live frames (which use local Date.now()).
+            window.chartData.timestamps.push(row.timestamp ? new Date(row.timestamp + 'Z').toLocaleTimeString() : '');
+            window.chartData.lp.push(parseFloat(row.lp || 0));
+            window.chartData.leq.push(parseFloat(row.leq || 0));
+            window.chartData.ln1.push(parseFloat(row.ln1 || 0));
+            window.chartData.ln2.push(parseFloat(row.ln2 || 0));
+        }
+        if (window.liveChart) {
+            window.liveChart.data.labels = window.chartData.timestamps;
+            window.liveChart.data.datasets[0].data = window.chartData.lp;
+            window.liveChart.data.datasets[1].data = window.chartData.leq;
+            window.liveChart.data.datasets[2].data = window.chartData.ln1;
+            window.liveChart.data.datasets[3].data = window.chartData.ln2;
+            window.liveChart.update('none');
+        }
+    } catch (e) {
+        console.warn('Chart backfill failed:', e);
+    }
+}
+
+async function initLiveDataStream(unitId) {
     // Close existing connection if any
     if (window.currentWebSocket) {
         window.currentWebSocket.close();
@@ -504,17 +554,24 @@ function initLiveDataStream(unitId) {
         window.chartData.timestamps = [];
         window.chartData.lp = [];
         window.chartData.leq = [];
+        window.chartData.ln1 = [];
+        window.chartData.ln2 = [];
     }
     if (window.liveChart && window.liveChart.data && window.liveChart.data.datasets) {
         window.liveChart.data.labels = [];
-        window.liveChart.data.datasets[0].data = [];
+        window.liveChart.data.datasets.forEach(ds => ds.data = []);
-        window.liveChart.data.datasets[1].data = [];
         window.liveChart.update();
     }
 
-    // WebSocket URL for SLMM backend via proxy
+    // Seed the chart with recent history BEFORE opening the live socket, so live
+    // frames append after the backfill (right order) and the chart isn't blank.
+    await backfillChart(unitId);
+
+    // WebSocket URL for SLMM backend via proxy.
+    // /monitor = the shared fan-out DOD feed (many viewers, one device connection,
+    // and it carries L1/L10 which the DRD /stream cannot).
     const wsProtocol = window.location.protocol === 'https:' ? 'wss:' : 'ws:';
-    const wsUrl = `${wsProtocol}//${window.location.host}/api/slmm/${unitId}/live`;
+    const wsUrl = `${wsProtocol}//${window.location.host}/api/slmm/${unitId}/monitor`;
 
     window.currentWebSocket = new WebSocket(wsUrl);
 
@@ -530,7 +587,11 @@ function initLiveDataStream(unitId) {
     window.currentWebSocket.onmessage = function(event) {
         try {
             const data = JSON.parse(event.data);
-            console.log('WebSocket data received:', data);
+            // The DOD monitor sends keepalive 'heartbeat' frames (no metrics) and a
+            // 'feed_status' on each frame. Reflect status, but don't let a heartbeat
+            // or an 'unreachable' frame blank the cards / spike the chart with zeros.
+            updateFeedStatus(data.feed_status);
+            if (data.heartbeat || data.feed_status === 'unreachable') return;
             updateLiveMetrics(data);
             updateLiveChart(data);
         } catch (error) {
@@ -559,6 +620,21 @@ function stopLiveDataStream() {
     }
 }
 
+// Reflect device reachability from the monitor feed's feed_status. Safe no-op
+// if the badge element isn't on the page.
+function updateFeedStatus(status) {
+    const el = document.getElementById('live-feed-status');
+    if (!el || status == null) return;
+    if (status === 'unreachable') {
+        el.textContent = 'Device offline';
+        el.className = 'text-xs font-medium px-2 py-0.5 rounded bg-red-100 text-red-700 dark:bg-red-900/40 dark:text-red-300';
+    } else {
+        el.textContent = 'Live';
+        el.className = 'text-xs font-medium px-2 py-0.5 rounded bg-green-100 text-green-700 dark:bg-green-900/40 dark:text-green-300';
+    }
+    el.style.display = '';
+}
+
 // Update metrics display
 function updateLiveMetrics(data) {
     if (document.getElementById('live-lp')) {
@@ -592,7 +668,9 @@ if (typeof window.chartData === 'undefined') {
     window.chartData = {
         timestamps: [],
         lp: [],
-        leq: []
+        leq: [],
+        ln1: [],
+        ln2: []
     };
 }
 
@@ -602,12 +680,17 @@ function updateLiveChart(data) {
     window.chartData.timestamps.push(now.toLocaleTimeString());
     window.chartData.lp.push(parseFloat(data.lp || 0));
     window.chartData.leq.push(parseFloat(data.leq || 0));
+    window.chartData.ln1.push(parseFloat(data.ln1 || 0));
+    window.chartData.ln2.push(parseFloat(data.ln2 || 0));
 
-    // Keep only last 60 data points
+    // Keep a rolling window large enough to hold the ~2h backfill (one point/min)
-    if (window.chartData.timestamps.length > 60) {
+    // plus a good run of live points before the oldest scroll off.
+    if (window.chartData.timestamps.length > 600) {
         window.chartData.timestamps.shift();
         window.chartData.lp.shift();
         window.chartData.leq.shift();
+        window.chartData.ln1.shift();
+        window.chartData.ln2.shift();
     }
 
     // Update chart if available
@@ -615,6 +698,8 @@ function updateLiveChart(data) {
         window.liveChart.data.labels = window.chartData.timestamps;
         window.liveChart.data.datasets[0].data = window.chartData.lp;
         window.liveChart.data.datasets[1].data = window.chartData.leq;
+        window.liveChart.data.datasets[2].data = window.chartData.ln1;
+        window.liveChart.data.datasets[3].data = window.chartData.ln2;
         window.liveChart.update('none');
     }
 }

templates/partials/slm_settings_modal.html

@@ -528,7 +528,7 @@ async function saveSLMSettings(event) {
             if (typeof checkFTPStatus === 'function') {
                 checkFTPStatus(unitId);
             }
-            if (typeof htmx !== 'undefined') {
+            if (typeof htmx !== 'undefined' && document.getElementById('slm-list')) {
                 htmx.trigger('#slm-list', 'load');
             }
         }, 1500);
@@ -604,8 +604,10 @@ async function toggleSLMDeployed() {
         successDiv.classList.remove('hidden');
         setTimeout(() => successDiv.classList.add('hidden'), 3000);
 
-        // Refresh any SLM list on the page
+        // Refresh any SLM list on the page (only if one is actually present —
-        if (typeof htmx !== 'undefined') {
+        // the detail/dashboard pages have no #slm-list, and htmx.trigger on a
+        // null target throws "can't access property dispatchEvent, e is null").
+        if (typeof htmx !== 'undefined' && document.getElementById('slm-list')) {
             htmx.trigger('#slm-list', 'load');
         }
     } catch (error) {

templates/sound_level_meters.html

@@ -51,14 +51,32 @@
 
 <!-- Live Measurement Chart - shows when a device is selected -->
 <div id="live-chart-panel" class="hidden bg-white dark:bg-slate-800 rounded-xl shadow-lg p-6 mb-8">
-    <div class="flex items-center justify-between mb-6">
+    <div class="flex items-start justify-between mb-6">
-        <h2 class="text-xl font-semibold text-gray-900 dark:text-white">Live Measurements</h2>
+        <div>
+            <h2 class="text-xl font-semibold text-gray-900 dark:text-white">
+                Live Measurements
+                <span id="panel-unit-id" class="text-seismo-orange"></span>
+            </h2>
+            <!-- Measuring state + cache freshness (populated from cached /status, no device hit) -->
+            <div class="mt-1 flex items-center gap-2 text-sm">
+                <span id="panel-measuring-badge" class="hidden px-2 py-0.5 text-xs font-medium rounded-full"></span>
+                <span id="panel-freshness" class="text-gray-500 dark:text-gray-400"></span>
+            </div>
+        </div>
+        <div class="flex items-center gap-3">
+            <button onclick="refreshDashboardPanel()" title="Refresh from device"
+                    class="text-gray-500 hover:text-seismo-orange dark:text-gray-400 dark:hover:text-seismo-orange">
+                <svg id="panel-refresh-icon" class="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                    <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M4 4v5h.582m15.356 2A8.001 8.001 0 004.582 9m0 0H9m11 11v-5h-.581m0 0a8.003 8.003 0 01-15.357-2m15.357 2H15"></path>
+                </svg>
+            </button>
             <button onclick="closeLiveChart()" class="text-gray-500 hover:text-gray-700 dark:text-gray-400 dark:hover:text-gray-200">
                 <svg class="w-6 h-6" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                     <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M6 18L18 6M6 6l12 12"></path>
                 </svg>
             </button>
         </div>
+    </div>
 
     <!-- Current Metrics -->
     <div class="grid grid-cols-5 gap-4 mb-6">
@@ -150,9 +168,18 @@ window.selectedUnitId = null;
 window.dashboardChartData = {
     timestamps: [],
     lp: [],
-    leq: []
+    leq: [],
+    ln1: [],
+    ln2: []
 };
 
+// Parse a metric to a number, or null (so a missing/"-.-" percentile leaves a gap
+// in the line instead of dropping it to 0).
+function numOrNull(v) {
+    const f = parseFloat(v);
+    return isNaN(f) ? null : f;
+}
+
 // Initialize Chart.js
 function initializeDashboardChart() {
     if (typeof Chart === 'undefined') {
@@ -194,6 +221,26 @@ function initializeDashboardChart() {
                     tension: 0.3,
                     borderWidth: 2,
                     pointRadius: 0
+                },
+                {
+                    label: 'L1',
+                    data: [],
+                    borderColor: 'rgb(168, 85, 247)',
+                    backgroundColor: 'rgba(168, 85, 247, 0.1)',
+                    tension: 0.3,
+                    borderWidth: 2,
+                    pointRadius: 0,
+                    spanGaps: true
+                },
+                {
+                    label: 'L10',
+                    data: [],
+                    borderColor: 'rgb(249, 115, 22)',
+                    backgroundColor: 'rgba(249, 115, 22, 0.1)',
+                    tension: 0.3,
+                    borderWidth: 2,
+                    pointRadius: 0,
+                    spanGaps: true
                 }
             ]
         },
@@ -244,12 +291,24 @@ function showLiveChart(unitId) {
         initializeDashboardChart();
     }
 
-    // Reset data
+    // Reset data for the newly-selected unit (clears any prior unit's line)
-    window.dashboardChartData = {
+    window.dashboardChartData = { timestamps: [], lp: [], leq: [], ln1: [], ln2: [] };
-        timestamps: [],
+    if (window.dashboardChart) {
-        lp: [],
+        window.dashboardChart.data.labels = [];
-        leq: []
+        window.dashboardChart.data.datasets.forEach(ds => ds.data = []);
-    };
+        window.dashboardChart.update('none');
+    }
+
+    // Name the unit; clear stale status until the cache read returns
+    const unitLabel = document.getElementById('panel-unit-id');
+    if (unitLabel) unitLabel.textContent = '· ' + unitId;
+    setPanelStatus(null, null);
+
+    // Populate immediately from CACHE (no device hit): KPI cards + chart trail.
+    prefillDashboardPanel(unitId);
+    backfillDashboardChart(unitId);
+    // Keep the cards updating from cache (~15s) without opening a device stream.
+    startPanelCachePolling(unitId);
 
     // Scroll to chart
     panel.scrollIntoView({ behavior: 'smooth', block: 'start' });
@@ -257,6 +316,7 @@ function showLiveChart(unitId) {
 
 function closeLiveChart() {
     stopDashboardStream();
+    stopPanelCachePolling();
     document.getElementById('live-chart-panel').classList.add('hidden');
     window.selectedUnitId = null;
 }
@@ -270,17 +330,12 @@ function startDashboardStream() {
         window.dashboardWebSocket.close();
     }
 
-    // Reset chart data
+    // The live WS takes over from the cache poller; keep the backfilled trail on
-    window.dashboardChartData = { timestamps: [], lp: [], leq: [] };
+    // the chart so the live frames continue the line instead of blanking it.
-    if (window.dashboardChart) {
+    stopPanelCachePolling();
-        window.dashboardChart.data.labels = [];
-        window.dashboardChart.data.datasets[0].data = [];
-        window.dashboardChart.data.datasets[1].data = [];
-        window.dashboardChart.update();
-    }
 
     const wsProtocol = window.location.protocol === 'https:' ? 'wss:' : 'ws:';
-    const wsUrl = `${wsProtocol}//${window.location.host}/api/slmm/${window.selectedUnitId}/live`;
+    const wsUrl = `${wsProtocol}//${window.location.host}/api/slmm/${window.selectedUnitId}/monitor`;
 
     window.dashboardWebSocket = new WebSocket(wsUrl);
 
@@ -293,6 +348,10 @@ function startDashboardStream() {
     window.dashboardWebSocket.onmessage = function(event) {
         try {
             const data = JSON.parse(event.data);
+            // /monitor sends keepalive 'heartbeat' frames (no metrics) and a per-frame
+            // 'feed_status'; skip heartbeats and offline frames so they don't blank the
+            // metrics or spike the chart with zeros.
+            if (data.heartbeat || data.feed_status === 'unreachable') return;
             updateDashboardMetrics(data);
             updateDashboardChart(data);
         } catch (error) {
@@ -316,6 +375,10 @@ function stopDashboardStream() {
         window.dashboardWebSocket.close();
         window.dashboardWebSocket = null;
     }
+    // Fall back to cache polling so the cards keep refreshing while the panel is open.
+    if (window.selectedUnitId && !document.getElementById('live-chart-panel').classList.contains('hidden')) {
+        startPanelCachePolling(window.selectedUnitId);
+    }
 }
 
 function updateDashboardMetrics(data) {
@@ -331,26 +394,200 @@ function updateDashboardMetrics(data) {
 }
 
 function updateDashboardChart(data) {
+    const cd = window.dashboardChartData;
     const now = new Date();
-    window.dashboardChartData.timestamps.push(now.toLocaleTimeString());
+    cd.timestamps.push(now.toLocaleTimeString());
-    window.dashboardChartData.lp.push(parseFloat(data.lp || 0));
+    cd.lp.push(numOrNull(data.lp));
-    window.dashboardChartData.leq.push(parseFloat(data.leq || 0));
+    cd.leq.push(numOrNull(data.leq));
+    // /monitor (DOD) frames carry ln1/ln2; a DRD frame would omit them -> null gap.
+    cd.ln1.push(numOrNull(data.ln1));
+    cd.ln2.push(numOrNull(data.ln2));
 
-    // Keep only last 60 data points
+    // Keep a generous window (backfill seeds up to ~120 points from the 2h trail).
-    if (window.dashboardChartData.timestamps.length > 60) {
+    if (cd.timestamps.length > 600) {
-        window.dashboardChartData.timestamps.shift();
+        cd.timestamps.shift();
-        window.dashboardChartData.lp.shift();
+        cd.lp.shift();
-        window.dashboardChartData.leq.shift();
+        cd.leq.shift();
+        cd.ln1.shift();
+        cd.ln2.shift();
     }
 
     if (window.dashboardChart) {
-        window.dashboardChart.data.labels = window.dashboardChartData.timestamps;
+        window.dashboardChart.data.labels = cd.timestamps;
-        window.dashboardChart.data.datasets[0].data = window.dashboardChartData.lp;
+        window.dashboardChart.data.datasets[0].data = cd.lp;
-        window.dashboardChart.data.datasets[1].data = window.dashboardChartData.leq;
+        window.dashboardChart.data.datasets[1].data = cd.leq;
+        window.dashboardChart.data.datasets[2].data = cd.ln1;
+        window.dashboardChart.data.datasets[3].data = cd.ln2;
         window.dashboardChart.update('none');
     }
 }
 
+// ---- Cached-data panel population (no device hit) -----------------------
+
+// Fill the KPI cards + measuring/freshness from the cached NL43Status snapshot.
+async function prefillDashboardPanel(unitId) {
+    try {
+        const r = await fetch(`/api/slmm/${encodeURIComponent(unitId)}/status`);
+        if (!r.ok) {                       // 404 = device has never reported yet
+            setPanelStatus(null, null);
+            return;
+        }
+        const d = (await r.json()).data || {};
+        updateDashboardMetrics(d);         // lp/leq/lmax/ln1/ln2 (ln guards keep cached percentiles)
+        const measuring = d.measurement_state === 'Start' || d.measurement_state === 'Measure';
+        setPanelStatus(measuring, d.last_seen);
+    } catch (e) {
+        console.warn('Panel cache prefill failed:', e);
+    }
+}
+
+// Seed the chart from the downsampled DOD trail so it shows recent trend on open.
+async function backfillDashboardChart(unitId) {
+    try {
+        const r = await fetch(`/api/slmm/${encodeURIComponent(unitId)}/history?hours=2`);
+        if (!r.ok) return;
+        const readings = (await r.json()).readings || [];
+        const cd = window.dashboardChartData;
+        if (!cd) return;
+        for (const row of readings) {
+            // Trail timestamps are naive UTC; append 'Z' to render in local time
+            // consistently with the live frames (which use local Date.now()).
+            cd.timestamps.push(row.timestamp ? new Date(row.timestamp + 'Z').toLocaleTimeString() : '');
+            cd.lp.push(numOrNull(row.lp));
+            cd.leq.push(numOrNull(row.leq));
+            cd.ln1.push(numOrNull(row.ln1));
+            cd.ln2.push(numOrNull(row.ln2));
+        }
+        if (window.dashboardChart) {
+            window.dashboardChart.data.labels = cd.timestamps;
+            window.dashboardChart.data.datasets[0].data = cd.lp;
+            window.dashboardChart.data.datasets[1].data = cd.leq;
+            window.dashboardChart.data.datasets[2].data = cd.ln1;
+            window.dashboardChart.data.datasets[3].data = cd.ln2;
+            window.dashboardChart.update('none');
+        }
+    } catch (e) {
+        console.warn('Panel chart backfill failed:', e);
+    }
+}
+
+// Measuring badge + "as of <time> (Xm ago)" freshness, so a cached value is never
+// mistaken for a live one. measuring: true | false | null(unknown).
+function setPanelStatus(measuring, lastSeenIso) {
+    const badge = document.getElementById('panel-measuring-badge');
+    const fresh = document.getElementById('panel-freshness');
+    if (badge) {
+        if (measuring === null) {
+            badge.className = 'hidden px-2 py-0.5 text-xs font-medium rounded-full';
+            badge.textContent = '';
+        } else if (measuring) {
+            badge.className = 'px-2 py-0.5 text-xs font-medium rounded-full bg-green-100 text-green-800 dark:bg-green-900/30 dark:text-green-300';
+            badge.textContent = '● Measuring';
+        } else {
+            badge.className = 'px-2 py-0.5 text-xs font-medium rounded-full bg-gray-200 text-gray-700 dark:bg-gray-700 dark:text-gray-300';
+            badge.textContent = '■ Stopped';
+        }
+    }
+    if (fresh) fresh.innerHTML = fmtFreshness(lastSeenIso);
+}
+
+// Human "x ago" with a staleness hint. Cached timestamps are naive UTC.
+function fmtFreshness(lastSeenIso) {
+    if (!lastSeenIso) return '<span class="text-gray-400">no cached reading yet</span>';
+    const t = new Date(lastSeenIso.endsWith('Z') ? lastSeenIso : lastSeenIso + 'Z');
+    const secs = Math.max(0, Math.round((Date.now() - t.getTime()) / 1000));
+    let ago, stale = false;
+    if (secs < 10) ago = 'just now';
+    else if (secs < 60) ago = secs + 's ago';
+    else if (secs < 3600) { ago = Math.round(secs / 60) + 'm ago'; stale = secs >= 300; }
+    else { ago = Math.round(secs / 3600) + 'h ago'; stale = true; }
+    const cls = stale ? 'text-amber-600 dark:text-amber-400' : 'text-gray-500 dark:text-gray-400';
+    const tag = stale ? ' · cached' : '';
+    return `as of ${t.toLocaleTimeString()} <span class="${cls}">(${ago}${tag})</span>`;
+}
+
+// Cache polling: refresh the cards from cache every 15s while the panel is open
+// and not live-streaming. Pure cache reads — no device contention.
+function startPanelCachePolling(unitId) {
+    stopPanelCachePolling();
+    window.panelCacheTimer = setInterval(() => {
+        if (window.selectedUnitId) prefillDashboardPanel(window.selectedUnitId);
+    }, 15000);
+}
+function stopPanelCachePolling() {
+    if (window.panelCacheTimer) { clearInterval(window.panelCacheTimer); window.panelCacheTimer = null; }
+}
+
+// ---- On-demand device refresh (the per-unit + panel refresh buttons) -----
+
+// One bounded, user-initiated device read: hits the device, updates the cache,
+// returns the fresh data. Throws on unreachable/disabled.
+async function forceDeviceRead(unitId) {
+    const r = await fetch(`/api/slmm/${encodeURIComponent(unitId)}/live`);
+    if (!r.ok) {
+        let detail = 'device unreachable';
+        try { detail = (await r.json()).detail || detail; } catch (e) {}
+        throw new Error(detail);
+    }
+    return (await r.json()).data || {};
+}
+
+function spinIcon(el, on) {
+    if (el) el.classList.toggle('animate-spin', on);
+}
+
+function applyFreshReadToPanel(unitId, d) {
+    if (window.selectedUnitId !== unitId) return;
+    updateDashboardMetrics(d);
+    const measuring = d.measurement_state === 'Start' || d.measurement_state === 'Measure';
+    // The read just happened, so "now" is the accurate freshness even if the
+    // /live payload doesn't echo last_seen.
+    setPanelStatus(measuring, d.last_seen || new Date().toISOString());
+}
+
+// Device-list row refresh button.
+async function refreshSlmUnit(unitId, btn) {
+    const icon = btn ? btn.querySelector('svg') : null;
+    if (btn) btn.disabled = true;
+    spinIcon(icon, true);
+    try {
+        const d = await forceDeviceRead(unitId);
+        applyFreshReadToPanel(unitId, d);
+        // Reload the list so the row's badge + last-check reflect the new cache.
+        if (typeof htmx !== 'undefined' && document.getElementById('slm-devices-list')) {
+            htmx.trigger('#slm-devices-list', 'load');
+        }
+        if (window.showToast) window.showToast(`${unitId} refreshed`, 'success');
+    } catch (e) {
+        if (window.showToast) window.showToast(`${unitId}: ${e.message}`, 'error');
+        else console.warn('refresh failed', e);
+    } finally {
+        if (btn) btn.disabled = false;
+        spinIcon(icon, false);
+    }
+}
+
+// Panel header refresh button (refreshes the unit the panel is showing).
+async function refreshDashboardPanel() {
+    const unitId = window.selectedUnitId;
+    if (!unitId) return;
+    const icon = document.getElementById('panel-refresh-icon');
+    spinIcon(icon, true);
+    try {
+        const d = await forceDeviceRead(unitId);
+        applyFreshReadToPanel(unitId, d);
+        updateDashboardChart(d);   // append the fresh point to the chart
+        if (typeof htmx !== 'undefined' && document.getElementById('slm-devices-list')) {
+            htmx.trigger('#slm-devices-list', 'load');
+        }
+        if (window.showToast) window.showToast(`${unitId} refreshed`, 'success');
+    } catch (e) {
+        if (window.showToast) window.showToast(`${unitId}: ${e.message}`, 'error');
+    } finally {
+        spinIcon(icon, false);
+    }
+}
+
 // Configuration modal - use unified SLM settings modal
 function openDeviceConfigModal(unitId) {
     // Call the unified modal function from slm_settings_modal.html