Messages
{
"action": "<string>",
"chain_id": 123,
"dataset_id": "<string>",
"params": {}
}{
"action": "<string>",
"chain_id": 123,
"dataset_id": "<string>"
}No examples foundNo examples found{
"chain_id": 123,
"dataset_id": "<string>",
"is_reorg": true,
"data": {
"block_number": 123,
"block_hash": "<string>",
"parent_block_hash": "<string>",
"miner": "<string>",
"timestamp_utc": "<string>",
"_tracing_id": "<string>"
}
}Primitives
Blocks
Subscribe to real-time canonical EVM block headers and integrity metadata.
WSS
Overview
- Dataset ID:
0101 - Blocks - Description: Canonical block headers with BlockDB integrity metadata.
- Sample: Hugging Face Sample
Subscription Parameters
Message Fields
Each message in the stream follows the standard block schema:Sequential block height.
Keccak-256 hash of the block header (32 bytes, hex string, no
0x prefix).Keccak-256 hash of the parent block.
Fee recipient / coinbase address.
Timestamp when the block was mined.
Tracing identifier for the canonical block record.
If
true, this message is a reorg correction and should be treated as an overwrite of previously emitted state at the same natural key (for blocks: block_number).Subscription Example
# Use wscat to connect and subscribe
wscat -c wss://api.blockdb.io/v1/evm/ \
-H "Authorization: Bearer $BLOCKDB_API_KEY" \
-x '{"action": "subscribe", "dataset_id": "0101", "chain_id": 1, "params": {}}'
Response Example
{
"chain_id": 1,
"dataset_id": "0101",
"is_reorg": false,
"data": {
"block_number": 12345678,
"block_hash": "7b5c0972efb6a0b5be4a4d4a0de5d1abd922478a53f32b2c717a800c862ba9e0",
"parent_block_hash": "f78e26c5959a94d6a62ed3837f5dcecf0d3761bf0a502e12a08fd7bc44c8568d",
"receipt_root": "b4d8cfe4b87590afe7ed95fbf7798142e8fb1ce86307ff0eb6580b8bc23de92f",
"miner": "0000000000000000000000000000000000000000",
"gas_limit": 30000000,
"extra_data": "636c61737369635f657468657265756d",
"size": 124836,
"timestamp_utc": "2025-11-11T18:42:15.123Z",
"_tracing_id": "010200000000000000000000000000000000",
"_computed_receipt_root": "b4d8cfe4b87590afe7ed95fbf7798142e8fb1ce86307ff0eb6580b8bc23de92f",
"_computed_receipt_timestamp_utc": "2025-11-11T18:43:00.000Z",
"_created_at": "2025-11-11T18:42:15.123Z",
"_updated_at": "2025-11-11T18:42:15.123Z"
}
}
Messages
{
"action": "<string>",
"chain_id": 123,
"dataset_id": "<string>",
"params": {}
}{
"action": "<string>",
"chain_id": 123,
"dataset_id": "<string>"
}No examples foundNo examples found{
"chain_id": 123,
"dataset_id": "<string>",
"is_reorg": true,
"data": {
"block_number": 123,
"block_hash": "<string>",
"parent_block_hash": "<string>",
"miner": "<string>",
"timestamp_utc": "<string>",
"_tracing_id": "<string>"
}
}subscribe
type:object
unsubscribe
type:object
subscribe_response
type:object
unsubscribe_response
type:object
update
type:object
Last modified on April 6, 2026
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