dsh-quake-alert

Usage

1. Open Settings → Disaster Alerts (灾害预警).
2. Watch regions: select the prefectures you live in or care about (leave empty for all of Japan).
3. Alert thresholds: set the minimum level for earthquake / EEW / tsunami alerts to avoid unnecessary interruptions.
4. Global watch points (0.4.0): if you care about places outside Japan — mainland China, Southeast Asia, Europe, the Americas — add a name, latitude, longitude and radius here (up to 20). "Use my location" fills the coordinates in from browser geolocation. An alert fires when the epicenter falls inside the radius and the magnitude reaches "Global earthquakes (minimum magnitude)". With no watch point added, global messages do not interrupt you (and do not enter the history).
   • To verify this path right away: click "Send test global alert (rotating scenarios)" just below. It builds EMSC / USGS / NOAA telegrams locally, runs them through the real parsers and matcher, and makes no network request at all, so you can click it as often as you like. Four scenarios rotate; the "distant earthquake" one deliberately falls outside the radius to show what the radius does. The result line reports what actually happened.
   • "Global source status" shows the EMSC connection plus how many increments each polled source (JMA / USGS / NOAA) has received and how long ago it last polled — so you can confirm the pipeline is alive. Worldwide earthquakes are infrequent by nature; hearing nothing is the normal state.
5. Disaster types: three switches — earthquake / EEW, tsunami, and weather alerts (landslides, floods, heavy rain, storm surges). Weather alerts have no threshold: the cut-off is fixed at level 4. "Send test weather alert (rotating scenarios)" verifies the whole path with a telegram built locally (no network request); each click rotates through landslide / flood / heavy rain / storm surge, plus an L3 case that deliberately stays silent. The result line reports what actually happened — whether it played, and the reason if it did not.
6. Notifications and sound: enable the alert tone and/or system notifications and adjust the volume. Use the preview buttons to check the tones, and "Test system notification" to grant permission and verify delivery.
7. Data source: keep "Production" for daily use; switch to "Sandbox" to verify the pipeline or see it in action (about one 2023 replay every 30 seconds).

When an alert matches, you get a tone plus a foreground toast or a background system notification, and the event is recorded in "Recent alerts".