/eth/v1/events

Subscribe to beacon node events

Gives subscribers to the beacon node's Server-Sent-Events stream an endpoint. To listen in on those events, users need use event source implementation.

SSE comments starting with: may be sent by servers for any reason, including maintaining the event stream connection when proxy servers are present.

Example Request and Result for /v1/events

In this section, we provide an illustrative example of a request made to retrieve details contents using the /v1/events endpoint. Additionally, we present the resulting response containing information about the node events subscription.

Parameters

Field	Type	Description
topics*	string	Event types to subscribe to Available values : head, block, attestation, voluntary_exit, bls_to_execution_change, finalized_checkpoint, chain_reorg, contribution_and_proof, light_client_finality_update, light_client_optimistic_update, payload_attributes

Examples of responses:

1. Media type: text/event-stream; Topics: head

Opened SSE stream.

Example Value | Schema

event: head
data: {"slot":"10", "block":"0x9a2fefd2fdb57f74993c7780ea5b9030d2897b615b89f808011ca5aebed54eaf", "state":"0x600e852a08c1200654ddf11025f1ceacb3c2e74bdd5c630cde0838b2591b69f9", "epoch_transition":false, "previous_duty_dependent_root":"0x5e0043f107cb57913498fbf2f99ff55e730bf1e151f02f221e977c91a90a0e91", "current_duty_dependent_root":"0x5e0043f107cb57913498fbf2f99ff55e730bf1e151f02f221e977c91a90a0e91", "execution_optimistic": false}

Example Description

The node has finished processing, resulting in a new head. previous_duty_dependent_root is get_block_root_at_slot(state, compute_start_slot_at_epoch(epoch - 1) - 1) and current_duty_dependent_root is get_block_root_at_slot(state, compute_start_slot_at_epoch(epoch) - 1). Both dependent roots use the genesis block root in the case of underflow.

2. Media type: text/event-stream; Topics: block

Example Value | Schema

event: block
data: {"slot":"10", "block":"0x9a2fefd2fdb57f74993c7780ea5b9030d2897b615b89f808011ca5aebed54eaf", "execution_optimistic": false}

3. Media type: text/event-stream; Topics: attestation

Example Value | Schema

event: attestation
data: {"aggregation_bits":"0x01", "signature":"0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505", "data":{"slot":"1", "index":"1", "beacon_block_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2", "source":{"epoch":"1", "root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"}, "target":{"epoch":"1", "root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"}}}

4. Media type: text/event-stream; Topics: voluntary_exit

Example Value | Schema

event: voluntary_exit
data: {"message":{"epoch":"1", "validator_index":"1"}, "signature":"0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"}

5. Media type: text/event-stream; Topics: bls_to_execution_change

Example Value | Schema

event: bls_to_execution_change
data: {"message":{"validator_index":"1", "from_bls_pubkey":"0x933ad9491b62059dd065b560d256d8957a8c402cc6e8d8ee7290ae11e8f7329267a8811c397529dac52ae1342ba58c95", "to_execution_address":"0x9be8d619c56699667c1fedcd15f6b14d8B067f72"}, "signature":"0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"}

6. Media type: text/event-stream; Topics: finalized_checkpoint

Example Value | Schema

event: finalized_checkpoint
data: {"block":"0x9a2fefd2fdb57f74993c7780ea5b9030d2897b615b89f808011ca5aebed54eaf", "state":"0x600e852a08c1200654ddf11025f1ceacb3c2e74bdd5c630cde0838b2591b69f9", "epoch":"2", "execution_optimistic": false }

7. Media type: text/event-stream; Topics: chain_reorg

Example Value | Schema

event: chain_reorg
data: {"slot":"200", "depth":"50", "old_head_block":"0x9a2fefd2fdb57f74993c7780ea5b9030d2897b615b89f808011ca5aebed54eaf", "new_head_block":"0x76262e91970d375a19bfe8a867288d7b9cde43c8635f598d93d39d041706fc76", "old_head_state":"0x9a2fefd2fdb57f74993c7780ea5b9030d2897b615b89f808011ca5aebed54eaf", "new_head_state":"0x600e852a08c1200654ddf11025f1ceacb3c2e74bdd5c630cde0838b2591b69f9", "epoch":"2", "execution_optimistic": false}

8. Media type: text/event-stream; Topics: contribution_and_proof

Example Value | Schema

event: contribution_and_proof
data: {"message": {"aggregator_index": "997", "contribution": {"slot": "168097", "beacon_block_root": "0x56f1fd4262c08fa81e27621c370e187e621a67fc80fe42340b07519f84b42ea1", "subcommittee_index": "0", "aggregation_bits": "0xffffffffffffffffffffffffffffffff", "signature": "0x85ab9018e14963026476fdf784cc674da144b3dbdb47516185438768774f077d882087b90ad642469902e782a8b43eed0cfc1b862aa9a473b54c98d860424a702297b4b648f3f30bdaae8a8b7627d10d04cb96a2cc8376af3e54a9aa0c8145e3"}, "selection_proof": "0x87c305f04bfe5db27c2b19fc23e00d7ac496ec7d3e759cbfdd1035cb8cf6caaa17a36a95a08ba78c282725e7b66a76820ca4eb333822bd399ceeb9807a0f2926c67ce67cfe06a0b0006838203b493505a8457eb79913ce1a3bcd1cc8e4ef30ed"}, "signature": "0xac118511474a94f857300b315c50585c32a713e4452e26a6bb98cdb619936370f126ed3b6bb64469259ee92e69791d9e12d324ce6fd90081680ce72f39d85d50b0ff977260a8667465e613362c6d6e6e745e1f9323ec1d6f16041c4e358839ac"}

9. Media type: text/event-stream; Topics: light_client_finality_update

Example Value | Schema

event: light_client_finality_update
data: {"version":"phase0", "data": {"attested_header": {"beacon": {"slot":"1", "proposer_index":"1", "parent_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2", "state_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2", "body_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"}}, "finalized_header": {"beacon": {"slot":"1", "proposer_index":"1", "parent_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2", "state_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2", "body_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"}}, "finality_branch": ["0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2", "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2", "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2", "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2", "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2", "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"], "sync_aggregate": {"sync_committee_bits":"0x01", "sync_committee_signature":"0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"}, "signature_slot":"1"}}

10. Media type: text/event-stream; Topics: light_client_optimistic_update

Example Value | Schema

event: light_client_optimistic_update
data: {"version":"phase0", "data": {"attested_header": {"beacon": {"slot":"1", "proposer_index":"1", "parent_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2", "state_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2", "body_root":"0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2"}}, "sync_aggregate": {"sync_committee_bits":"0x01", "sync_committee_signature":"0x1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505cc411d61252fb6cb3fa0017b679f8bb2305b26a285fa2737f175668d0dff91cc1b66ac1fb663c9bc59509846d6ec05345bd908eda73e670af888da41af171505"}, "signature_slot":"1"}}

11. Media type: text/event-stream; Topics: payload_attributes

Example Value | Schema

event: payload_attributes
data: {"version": "capella", "data": {"proposer_index": "123", "proposal_slot": "10", "parent_block_number": "9", "parent_block_root": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2", "parent_block_hash": "0x9a2fefd2fdb57f74993c7780ea5b9030d2897b615b89f808011ca5aebed54eaf", "payload_attributes": {"timestamp": "123456", "prev_randao": "0xcf8e0d4e9587369b2301d0790347320302cc0943d5a1884560367e8208d920f2", "suggested_fee_recipient": "0x0000000000000000000000000000000000000000", "withdrawals": [{"index": "5", "validator_index": "10", "address": "0x0000000000000000000000000000000000000000", "amount": "15640"}]}}},

The example in this section uses a non-existing project id.

Make sure you replace it with your Ethereum Holesky Beacon endpoint when issuing the API calls.

Don't have a project id? Here's a straightforward guide on how to obtain one!

Subscribe to beacon node events

GET https://eth-holesky-beacon.blastapi.io/<project-id>/eth/v1/events

Query Parameters

Name	Type	Description
topics *	string	head

200: OK Expand for a detailed response example

Opened SSE stream.

Curl Request example

curl -X 'GET' \
  'https://eth-holesky-beacon.blastapi.io/<project-id>/eth/v1/events?topics=head' \
  -H 'accept: application/json'