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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 network. See the Chain enumeration.
​
path_ids
string[]
Optional filters: 32-byte path_id values (hex string, no 0x prefix).

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Message Fields

Payload fields mirror blockdb_evm.b0901_arb_opportunities_v1 (addresses and binary ids as hex strings without 0x in JSON).
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block_number
number
Observation block.
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block_time
string
UTC timestamp of the observation (ISO-8601).
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tx_index
number
Transaction index within the block.
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log_index
number
Log index within the transaction.
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path_id
string
32-byte path id (hex).
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is_reversed
boolean
true if the path was evaluated in the reversed direction.
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pool_uids
string[]
Pool UIDs in evaluated (directional) order (hex).
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token_path
string[]
Token addresses in evaluated order (hex).
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amounts
string[]
Per-hop amounts as decimal strings, aligned with token_path.
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profit_in_tokens
string
Estimated profit in token_path[0] units (decimal string).
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token_vwap_usd
string
USD price of token_path[0] (decimal string).
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profit_in_usd
string
Estimated profit in USD (decimal string).
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_tracing_id
string
Row tracing id (hex).
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_parent_tracing_ids
string[]
Parent tracing ids (hex).
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_created_at
string
Record creation timestamp (ISO-8601).
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_updated_at
string
Last update timestamp (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": "0901", "chain_id": 1, "params": {}}'

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Response Example

{
  "chain_id": 1,
  "dataset_id": "0901",
  "is_reorg": false,
  "data": {
    "block_number": 21000500,
    "block_time": "2025-11-11T12:00:00Z",
    "tx_index": 8,
    "log_index": 4,
    "path_id": "a1b2c3d4e5f6789012345678901234567890abcd1234567890abcdef12345678",
    "is_reversed": false,
    "pool_uids": [
      "88e6a0c2ddd26feeb64f039a2c41296fcb3f5640000000000000000000000000",
      "11b815acc87f6f89741a636d1ebfcea40876f8f0000000000000000000000000"
    ],
    "token_path": [
      "c02aaa39b223fe8d0a0e5c4f27ead9083c756cc2",
      "a0b86991c6218b36c1d19d4a2e9eb0ce3606eb48",
      "c02aaa39b223fe8d0a0e5c4f27ead9083c756cc2"
    ],
    "amounts": [
      "1000000000000000000",
      "3500000000",
      "1000500000000000000"
    ],
    "profit_in_tokens": "50000000000000000",
    "token_vwap_usd": "3200.50",
    "profit_in_usd": "160.025",
    "_tracing_id": "0901c0ffee000000000000000000000000000000000000000000000000000001",
    "_parent_tracing_ids": [
      "0801c0ffee000000000000000000000000000000000000000000000000000001"
    ],
    "_created_at": "2025-11-11T12:00:05Z",
    "_updated_at": "2025-11-11T12:00:05Z"
  }
}
Last modified on April 6, 2026