Add YAML-driven report generation

README.md

@@ -24,6 +24,29 @@ python scripts/generate_reports.py monthly
 
 Reports are written under the `output/` directory. Each command updates the corresponding `<interval>.json` file and produces an HTML dashboard using Chart.js.
 
+### Configuring Reports
+
+Report queries are defined in `reports.yml`. Each entry specifies the `name`,
+`interval`, optional `label` and `chart` type, and a SQL `query` that must return
+`bucket` and `value` columns. When `generate_reports.py` runs, every matching
+definition creates `output/<interval>/<name>.json` and an interval dashboard.
+
+Example snippet:
+
+```yaml
+- name: hits
+  interval: hourly
+  chart: bar
+  query: |
+    SELECT strftime('%Y-%m-%d %H:00:00', datetime(time)) AS bucket,
+           COUNT(*) AS value
+    FROM logs
+    GROUP BY bucket
+    ORDER BY bucket
+```
+
+Add or modify entries in `reports.yml` to tailor the generated metrics.
+
 ## Importing Logs
 
 Use the `run-import.sh` script to set up the Python environment if needed and import the latest Nginx log entries into `database/ngxstat.db`.