github.com/fiagdao/tendermint@v0.32.11-0.20220824195748-2087fcc480c1/docs/app-dev/subscribing-to-events-via-websocket.md (about)

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