blockSubscribe RPC Method

Subscribe to receive notification anytime a new block is confirmed or finalized.

Unstable Method

This subscription is considered unstable and is only available if the validator was started with the --rpc-pubsub-enable-block-subscription flag. The format of this subscription may change in the future.

Parameters

filter string | object required

filter criteria for the logs to receive results by account type; currently supported:

string

all - include all transactions in block

object

A JSON object with the following field:

mentionsAccountOrProgram: <string> - return only transactions that mention the provided public key (as base-58 encoded string). If no mentions in a given block, then no notification will be sent.

object optional

Configuration object containing the following fields:

commitment string optional

Default: finalized

processed is not supported.

encoding string optional

Default: json

encoding format for each returned Transaction

Values: jsonjsonParsedbase58base64

jsonParsed attempts to use program-specific instruction parsers to return more human-readable and explicit data in the transaction.message.instructions list.
If jsonParsed is requested but a parser cannot be found, the instruction falls back to regular JSON encoding (accounts, data, and programIdIndex fields).

transactionDetails string optional

Default: full

level of transaction detail to return

Values: fullaccountssignaturesnone

If accounts are requested, transaction details only include signatures and an annotated list of accounts in each transaction.
Transaction metadata is limited to only: fee, err, pre_balances, post_balances, pre_token_balances, and post_token_balances.

maxSupportedTransactionVersion number optional

the max transaction version to return in responses.

If the requested block contains a transaction with a higher version, an error will be returned.
If this parameter is omitted, only legacy transactions will be returned, and a block containing any versioned transaction will prompt the error.

showRewards bool optional

whether to populate the rewards array. If parameter not provided, the default includes rewards.

Result

integer - subscription id (needed to unsubscribe)

Code sample

{
  "jsonrpc": "2.0",
  "id": "1",
  "method": "blockSubscribe",
  "params": ["all"]
}

{
  "jsonrpc": "2.0",
  "id": "1",
  "method": "blockSubscribe",
  "params": [
    {
      "mentionsAccountOrProgram": "LieKvPRE8XeX3Y2xVNHjKlpAScD12lYySBVQ4HqoJ5op"
    },
    {
      "commitment": "confirmed",
      "encoding": "base64",
      "showRewards": true,
      "transactionDetails": "full"
    }
  ]
}

Response

{ "jsonrpc": "2.0", "result": 0, "id": 1 }

Notification Format:

The notification will be an object with the following fields:

slot: <u64> - The corresponding slot.
err: <object|null> - Error if something went wrong publishing the notification otherwise null.
block: <object|null> - A block object as seen in the getBlock RPC HTTP method.

{
  "jsonrpc": "2.0",
  "method": "blockNotification",
  "params": {
    "result": {
      "context": {
        "slot": 112301554
      },
      "value": {
        "slot": 112301554,
        "block": {
          "previousBlockhash": "GJp125YAN4ufCSUvZJVdCyWQJ7RPWMmwxoyUQySydZA",
          "blockhash": "6ojMHjctdqfB55JDpEpqfHnP96fiaHEcvzEQ2NNcxzHP",
          "parentSlot": 112301553,
          "transactions": [
            {
              "transaction": [
                "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",
                "base64"
              ],
              "meta": {
                "err": null,
                "status": {
                  "Ok": null
                },
                "fee": 5000,
                "preBalances": [
                  1758510880, 2067120, 1566000, 1461600, 2039280, 2039280,
                  1900080, 1865280, 0, 3680844220, 2039280
                ],
                "postBalances": [
                  1758505880, 2067120, 1566000, 1461600, 2039280, 2039280,
                  1900080, 1865280, 0, 3680844220, 2039280
                ],
                "innerInstructions": [
                  {
                    "index": 0,
                    "instructions": [
                      {
                        "programIdIndex": 13,
                        "accounts": [1, 15, 3, 4, 2, 14],
                        "data": "21TeLgZXNbtHXVBzCaiRmH"
                      },
                      {
                        "programIdIndex": 14,
                        "accounts": [3, 4, 1],
                        "data": "6qfC8ic7Aq99"
                      },
                      {
                        "programIdIndex": 13,
                        "accounts": [1, 15, 3, 5, 2, 14],
                        "data": "21TeLgZXNbsn4QEpaSEr3q"
                      },
                      {
                        "programIdIndex": 14,
                        "accounts": [3, 5, 1],
                        "data": "6LC7BYyxhFRh"
                      }
                    ]
                  },
                  {
                    "index": 1,
                    "instructions": [
                      {
                        "programIdIndex": 14,
                        "accounts": [4, 3, 0],
                        "data": "7aUiLHFjSVdZ"
                      },
                      {
                        "programIdIndex": 19,
                        "accounts": [17, 18, 16, 9, 11, 12, 14],
                        "data": "8kvZyjATKQWYxaKR1qD53V"
                      },
                      {
                        "programIdIndex": 14,
                        "accounts": [9, 11, 18],
                        "data": "6qfC8ic7Aq99"
                      }
                    ]
                  }
                ],
                "logMessages": [
                  "Program QMNeHCGYnLVDn1icRAfQZpjPLBNkfGbSKRB83G5d8KB invoke [1]",
                  "Program QMWoBmAyJLAsA1Lh9ugMTw2gciTihncciphzdNzdZYV invoke [2]"
                ],
                "preTokenBalances": [
                  {
                    "accountIndex": 4,
                    "mint": "iouQcQBAiEXe6cKLS85zmZxUqaCqBdeHFpqKoSz615u",
                    "uiTokenAmount": {
                      "uiAmount": null,
                      "decimals": 6,
                      "amount": "0",
                      "uiAmountString": "0"
                    },
                    "owner": "LieKvPRE8XeX3Y2xVNHjKlpAScD12lYySBVQ4HqoJ5op",
                    "programId": "TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA"
                  },
                  {
                    "accountIndex": 5,
                    "mint": "iouQcQBAiEXe6cKLS85zmZxUqaCqBdeHFpqKoSz615u",
                    "uiTokenAmount": {
                      "uiAmount": 11513.0679,
                      "decimals": 6,
                      "amount": "11513067900",
                      "uiAmountString": "11513.0679"
                    },
                    "owner": "rXhAofQCT7NN9TUqigyEAUzV1uLL4boeD8CRkNBSkYk",
                    "programId": "TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA"
                  },
                  {
                    "accountIndex": 10,
                    "mint": "Saber2gLauYim4Mvftnrasomsv6NvAuncvMEZwcLpD1",
                    "uiTokenAmount": {
                      "uiAmount": null,
                      "decimals": 6,
                      "amount": "0",
                      "uiAmountString": "0"
                    },
                    "owner": "CL9wkGFT3SZRRNa9dgaovuRV7jrVVigBUZ6DjcgySsCU",
                    "programId": "TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb"
                  },
                  {
                    "accountIndex": 11,
                    "mint": "Saber2gLauYim4Mvftnrasomsv6NvAuncvMEZwcLpD1",
                    "uiTokenAmount": {
                      "uiAmount": 15138.514093,
                      "decimals": 6,
                      "amount": "15138514093",
                      "uiAmountString": "15138.514093"
                    },
                    "owner": "LieKvPRE8XeX3Y2xVNHjKlpAScD12lYySBVQ4HqoJ5op",
                    "programId": "TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb"
                  }
                ],
                "postTokenBalances": [
                  {
                    "accountIndex": 4,
                    "mint": "iouQcQBAiEXe6cKLS85zmZxUqaCqBdeHFpqKoSz615u",
                    "uiTokenAmount": {
                      "uiAmount": null,
                      "decimals": 6,
                      "amount": "0",
                      "uiAmountString": "0"
                    },
                    "owner": "LieKvPRE8XeX3Y2xVNHjKlpAScD12lYySBVQ4HqoJ5op",
                    "programId": "TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA"
                  },
                  {
                    "accountIndex": 5,
                    "mint": "iouQcQBAiEXe6cKLS85zmZxUqaCqBdeHFpqKoSz615u",
                    "uiTokenAmount": {
                      "uiAmount": 11513.103028,
                      "decimals": 6,
                      "amount": "11513103028",
                      "uiAmountString": "11513.103028"
                    },
                    "owner": "rXhAofQCT7NN9TUqigyEAUzV1uLL4boeD8CRkNBSkYk",
                    "programId": "TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA"
                  },
                  {
                    "accountIndex": 10,
                    "mint": "Saber2gLauYim4Mvftnrasomsv6NvAuncvMEZwcLpD1",
                    "uiTokenAmount": {
                      "uiAmount": null,
                      "decimals": 6,
                      "amount": "0",
                      "uiAmountString": "0"
                    },
                    "owner": "CL9wkGFT3SZRRNa9dgaovuRV7jrVVigBUZ6DjcgySsCU",
                    "programId": "TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb"
                  },
                  {
                    "accountIndex": 11,
                    "mint": "Saber2gLauYim4Mvftnrasomsv6NvAuncvMEZwcLpD1",
                    "uiTokenAmount": {
                      "uiAmount": 15489.767829,
                      "decimals": 6,
                      "amount": "15489767829",
                      "uiAmountString": "15489.767829"
                    },
                    "owner": "BeiHVPRE8XeX3Y2xVNrSsTpAScH94nYySBVQ4HqgN9at",
                    "programId": "TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb"
                  }
                ],
                "rewards": []
              }
            }
          ],
          "blockTime": 1639926816,
          "blockHeight": 101210751
        },
        "err": null
      }
    },
    "subscription": 14
  }
}