github.com/number571/tendermint@v0.34.11-gost/docs/tendermint-core/subscription.md (about)

     1  ---
     2  order: 7
     3  ---
     4  
     5  # Subscribing to events via Websocket
     6  
     7  Tendermint emits different events, which you can subscribe to via
     8  [Websocket](https://en.wikipedia.org/wiki/WebSocket). This can be useful
     9  for third-party applications (for analysis) or for inspecting state.
    10  
    11  [List of events](https://godoc.org/github.com/number571/tendermint/types#pkg-constants)
    12  
    13  To connect to a node via websocket from the CLI, you can use a tool such as
    14  [wscat](https://github.com/websockets/wscat) and run:
    15  
    16  ```sh
    17  wscat ws://127.0.0.1:26657/websocket
    18  ```
    19  
    20  You can subscribe to any of the events above by calling the `subscribe` RPC
    21  method via Websocket along with a valid query.
    22  
    23  ```json
    24  {
    25      "jsonrpc": "2.0",
    26      "method": "subscribe",
    27      "id": 0,
    28      "params": {
    29          "query": "tm.event='NewBlock'"
    30      }
    31  }
    32  ```
    33  
    34  Check out [API docs](https://docs.tendermint.com/master/rpc/) for
    35  more information on query syntax and other options.
    36  
    37  You can also use tags, given you had included them into DeliverTx
    38  response, to query transaction results. See [Indexing
    39  transactions](../app-dev/indexing-transactions.md) for details.
    40  
    41  ## ValidatorSetUpdates
    42  
    43  When validator set changes, ValidatorSetUpdates event is published. The
    44  event carries a list of pubkey/power pairs. The list is the same
    45  Tendermint receives from ABCI application (see [EndBlock
    46  section](https://github.com/tendermint/spec/blob/master/spec/abci/abci.md#endblock) in
    47  the ABCI spec).
    48  
    49  Response:
    50  
    51  ```json
    52  {
    53      "jsonrpc": "2.0",
    54      "id": 0,
    55      "result": {
    56          "query": "tm.event='ValidatorSetUpdates'",
    57          "data": {
    58              "type": "tendermint/event/ValidatorSetUpdates",
    59              "value": {
    60                "validator_updates": [
    61                  {
    62                    "address": "09EAD022FD25DE3A02E64B0FE9610B1417183EE4",
    63                    "pub_key": {
    64                      "type": "tendermint/PubKeyEd25519",
    65                      "value": "ww0z4WaZ0Xg+YI10w43wTWbBmM3dpVza4mmSQYsd0ck="
    66                    },
    67                    "voting_power": "10",
    68                    "proposer_priority": "0"
    69                  }
    70                ]
    71              }
    72          }
    73      }
    74  }
    75  ```