Introduction to WebSocket

• The WebSocket API automatically pushes relevant information to all clients when the server receives an EEW
• Heartbeat mechanism: The server sends a heartbeat packet every minute or after the connection is established to maintain the connection. The client can optionally reply with a ping packet (recommended).

WebSocket Call URLs

• Receive all JSON API pushes:
wss://ws-api.wolfx.jp/all_eew
• Sichuan Earthquake Early Warning JSON API:
wss://ws-api.wolfx.jp/sc_eew
• JMA Earthquake Early Warning JSON API:
wss://ws-api.wolfx.jp/jma_eew
• Fujian Earthquake Early Warning JSON API:
wss://ws-api.wolfx.jp/fj_eew
• China Earthquake Networks Center Earthquake Early Warning JSON API:
wss://ws-api.wolfx.jp/cenc_eew
• China Earthquake Networks Center Earthquake Information JSON API:
wss://ws-api.wolfx.jp/cenc_eqlist
• JMA Earthquake Information JSON API:
wss://ws-api.wolfx.jp/jma_eqlist
• For detailed JSON field parsing, refer to: https://api.wolfx.jp

WebSocket Manual Query Commands

• Ping:
ping
• Sichuan Earthquake Early Warning JSON:
query_sceew
• JMA Earthquake Early Warning JSON:
query_jmaeew
• Fujian Earthquake Early Warning JSON:
query_fjeew
• China Earthquake Networks Center Earthquake Early Warning JSON:
query_cenceew
• China Earthquake Networks Center Earthquake Information JSON:
query_cenceqlist
• JMA Earthquake Information JSON:
query_jmaeqlist

WebSocket JSON Data Specification

• Common JSON Field Description:

type	Data type / data source (see API homepage for specific values) (String)

• WebSocket Heartbeat Packet - JSON Field Description:

type	heartbeat (String)
ver	Server version number (Number)
id	Client connection UUID (String)
timestamp	Heartbeat sent timestamp in milliseconds (String)

• WebSocket Pong Packet - JSON Field Description:

type	pong (String)
timestamp	Pong sent timestamp in milliseconds (String)

Doc version: v20250913