--- order: 7 --- # Subscribing to events via Websocket Tendermint emits different events, which you can subscribe to via [Websocket](https://en.wikipedia.org/wiki/WebSocket). This can be useful for third-party applications (for analysis) or for inspecting state. [List of events](https://godoc.org/github.com/tendermint/tendermint/types#pkg-constants) To connect to a node via websocket from the CLI, you can use a tool such as [wscat](https://github.com/websockets/wscat) and run: ```sh wscat ws://127.0.0.1:26657/websocket ``` You can subscribe to any of the events above by calling the `subscribe` RPC method via Websocket along with a valid query. ```json { "jsonrpc": "2.0", "method": "subscribe", "id": 0, "params": { "query": "tm.event='NewBlock'" } } ``` Check out [API docs](https://docs.tendermint.com/master/rpc/) for more information on query syntax and other options. You can also use tags, given you had included them into DeliverTx response, to query transaction results. See [Indexing transactions](./indexing-transactions.md) for details. ## ValidatorSetUpdates When validator set changes, ValidatorSetUpdates event is published. The event carries a list of pubkey/power pairs. The list is the same Tendermint receives from ABCI application (see [EndBlock section](https://github.com/tendermint/spec/blob/master/spec/abci/abci.md#endblock) in the ABCI spec). Response: ```json { "jsonrpc": "2.0", "id": 0, "result": { "query": "tm.event='ValidatorSetUpdates'", "data": { "type": "tendermint/event/ValidatorSetUpdates", "value": { "validator_updates": [ { "address": "09EAD022FD25DE3A02E64B0FE9610B1417183EE4", "pub_key": { "type": "tendermint/PubKeyEd25519", "value": "ww0z4WaZ0Xg+YI10w43wTWbBmM3dpVza4mmSQYsd0ck=" }, "voting_power": "10", "proposer_priority": "0" } ] } } } } ```