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WSS
Messages
subscribe
type:object
unsubscribe
type:object
subscribe_response
type:object
unsubscribe_response
type:object
update
type:object

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Overview

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Subscription Parameters

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chain_id
number
required
Target EVM chain. See the Chain enumeration for supported values.
​
base_token_address
string
required
ERC-20 contract address for the base asset (hex string, 20 bytes, no 0x prefix).
​
quote_token_address
string
required
ERC-20 contract address for the quote asset (hex string, 20 bytes, no 0x prefix).

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Message Fields

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pool_uid
string
Pool identifier.
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exchange_id
number
Exchange/DEX identifier.
​
type_id
number
Pool type identifier.
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block_number
number
Block height where the swap occurred.
​
block_time
string
Block time (ISO-8601).
​
tx_index
number
Transaction index.
​
log_index
number
Log index.
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token_in
string
Address of the input token.
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token_out
string
Address of the output token.
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amount_in
string
Amount of token_in (raw units, integer string).
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amount_out
string
Amount of token_out (raw units, integer string).
​
exec_price
string | null
Realized execution price: token_out per 1 token_in (decimals-adjusted). May be null.
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_tracing_id
string
Row-level lineage hash for correlation.
​
_parent_tracing_ids
string[]
Parent lineage ids (hex).
​
_created_at
string
Record creation time (ISO-8601).
​
_updated_at
string
Record last update time (ISO-8601).

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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": "0302", "chain_id": 1, "params": {"base_token_address": "c02aaa39b223fe8d0a0e5c4f27ead9083c756cc2", "quote_token_address": "a0b86991c6218b36c1d19d4a2e9eb0ce3606eb48"}}'

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Response Example

{
  "chain_id": 1,
  "dataset_id": "0302",
  "is_reorg": false,
  "data": {
    "pool_uid": "88e6a0c2ddd26feeb64f039a2c41296fcb3f5640000000000000000000000000",
    "exchange_id": 1,
    "type_id": 201,
    "block_number": 18930123,
    "block_time": "2025-11-11T18:15:30.000Z",
    "tx_index": 5,
    "log_index": 12,
    "token_in": "c02aaa39b223fe8d0a0e5c4f27ead9083c756cc2",
    "token_out": "a0b86991c6218b36c1d19d4a2e9eb0ce3606eb48",
    "amount_in": "10000000000000000000",
    "amount_out": "30241122334455667788990",
    "exec_price": "3024.112233445566778899",
    "_tracing_id": "0302000000000000000000000000000000000001",
    "_parent_tracing_ids": [
      "0203000000000000000000000000000000000000"
    ],
    "_created_at": "2025-11-11T18:15:35.000Z",
    "_updated_at": "2025-11-11T18:15:35.000Z"
  }
}
Last modified on April 6, 2026