first commit

2025-11-28 00:20:23 +03:00
commit a8473eec11
13 changed files with 649 additions and 0 deletions
--- a/watcher_visio/metrics/templates/dashboard.html
+++ b/watcher_visio/metrics/templates/dashboard.html
@@ -0,0 +1,52 @@
+<!doctype html>
+<html>
+  <head>
+    <meta charset="utf-8"/>
+    <title>Prometheus dashboard</title>
+    <script src="https://cdn.jsdelivr.net/npm/chart.js"></script>
+  </head>
+  <body>
+    <h1>Prometheus dashboard</h1>
+    <div>
+      <label>Metric: <input id="metric" value="{{ default_metric }}"/></label>
+      <button id="reload">Reload</button>
+      <a id="pdfLink" href="/report/pdf/?metric={{ default_metric }}" target="_blank">Download PDF</a>
+    </div>
+
+    <canvas id="chart" width="900" height="400"></canvas>
+
+    <script>
+      const ctx = document.getElementById('chart').getContext('2d');
+      let chart = null;
+      async function loadData() {
+        const metric = document.getElementById('metric').value;
+        const res = await fetch(`/api/metrics/?metric=${encodeURIComponent(metric)}`);
+        const payload = await res.json();
+        const labels = (payload.labels || []).map(ts => new Date(ts));
+        const datasets = (payload.datasets || []).map((d, i) => ({
+          label: d.label,
+          data: d.data.map((v, idx) => ({x: labels[idx], y: v})),
+          fill: false,
+          // Chart.js will auto pick colors
+        }));
+        if (chart) chart.destroy();
+        chart = new Chart(ctx, {
+          type: 'line',
+          data: { datasets },
+          options: {
+            parsing: false,
+            scales: {
+              x: { type: 'time', time: { unit: 'minute' } },
+              y: { beginAtZero: true }
+            }
+          }
+        });
+        // update PDF link
+        document.getElementById('pdfLink').href = `/report/pdf/?metric=${encodeURIComponent(metric)}`;
+      }
+
+      document.getElementById('reload').addEventListener('click', loadData);
+      loadData();
+    </script>
+  </body>
+</html>
--- a/watcher_visio/metrics/urls.py
+++ b/watcher_visio/metrics/urls.py
@@ -0,0 +1,8 @@
+from django.urls import path
+from . import views
+
+urlpatterns = [
+    path("", views.dashboard, name="dashboard"),
+    path("api/metrics/", views.metrics_api, name="metrics_api"),
+    path("report/pdf/", views.report_pdf, name="report_pdf"),
+]
--- a/watcher_visio/metrics/views.py
+++ b/watcher_visio/metrics/views.py
@@ -0,0 +1,90 @@
+import os
+import json
+import time
+import requests
+from django.conf import settings
+from django.shortcuts import render
+from django.http import JsonResponse, HttpResponse
+from django.template.loader import render_to_string
+
+# Helper: query Prometheus HTTP API (query_range)
+def query_prometheus_range(query, start, end, step="60s"):
+    url = settings.PROMETHEUS_URL.rstrip("/") + "/api/v1/query_range"
+    params = {"query": query, "start": start, "end": end, "step": step}
+    r = requests.get(url, params=params, timeout=10)
+    r.raise_for_status()
+    return r.json()
+
+# API endpoint used by Chart.js frontend
+def metrics_api(request):
+    # get parameters or default (last 1 hour)
+    metric = request.GET.get("metric", settings.PROMETHEUS_DEFAULT_METRIC)
+    now = int(time.time())
+    start = request.GET.get("start", str(now - 3600))  # unix epoch seconds
+    end = request.GET.get("end", str(now))
+    step = request.GET.get("step", "60s")
+
+    # Example: if the metric is a gauge giving bytes, we may want to convert ... keep raw for now
+    q = metric
+    data = query_prometheus_range(q, start, end, step)
+    # Prometheus returns JSON; keep it minimal for Chart.js: {labels: [...], datasets: [{label,...,data:[...]}]}
+    series = []
+    labels = []
+    datasets = []
+
+    if data.get("status") != "success":
+        return JsonResponse({"error": "prometheus error", "detail": data})
+
+    result = data["data"]["result"]  # list of time series
+    # if no series, return empty
+    if not result:
+        return JsonResponse({"labels": [], "datasets": []})
+
+    # Build labels from first series timestamps
+    # Prometheus returns values as [[ts, value], ...]
+    first_values = result[0]["values"]
+    labels = [int(float(t[0])) * 1000 for t in first_values]  # JS prefers ms
+    for s in result:
+        # create dataset for each timeseries (label from metric labels)
+        metric_labels = s.get("metric", {})
+        label = metric_labels.get("instance") or metric_labels.get("domain") or json.dumps(metric_labels)
+        values = [float(v[1]) if v[1] != "NaN" else None for v in s["values"]]
+        datasets.append({
+            "label": label,
+            "data": values,
+        })
+
+    return JsonResponse({"labels": labels, "datasets": datasets})
+
+# Dashboard page (Jinja template)
+def dashboard(request):
+    # let template ask API for data with JS.
+    return render(request, "dashboard.html", {
+        "default_metric": settings.PROMETHEUS_DEFAULT_METRIC,
+    })
+
+# Render page to PDF using WeasyPrint
+def report_pdf(request):
+    # optionally accept ?metric=...&start=...&end=...
+    metric = request.GET.get("metric", settings.PROMETHEUS_DEFAULT_METRIC)
+    now = int(time.time())
+    start = int(request.GET.get("start", now - 3600))
+    end = int(request.GET.get("end", now))
+
+    # fetch data server-side to include in report
+    try:
+        resp = query_prometheus_range(metric, start, end, step="60s")
+    except Exception as e:
+        return HttpResponse(f"Error fetching metrics: {e}", status=500)
+
+    context = {
+        "metric": metric,
+        "prom_data": resp.get("data", {}),
+        "generated_at": time.strftime("%Y-%m-%d %H:%M:%S", time.gmtime()),
+    }
+    html = render_to_string("report.html", context)
+
+    # Generate PDF via WeasyPrint
+    from weasyprint import HTML
+    pdf = HTML(string=html, base_url=request.build_absolute_uri("/")).write_pdf()
+    return HttpResponse(pdf, content_type="application/pdf")