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Subscribe to receive logs from preconfirmed transactions matching an optional filter. Useful for monitoring contract events with sub-block latency.
This method is only available on Flashblocks-aware endpoints. Connect to https://mainnet-preconf.base.org (or https://sepolia-preconf.base.org) to use it.
Requires base/base minimum client version v0.3.1.

Parameters

subscriptionType
string
required
Must be "pendingLogs".
filterOptions
object
Optional log filter.

Returns

result
string
Hex-encoded subscription ID.

Example

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "eth_subscribe",
  "params": [
    "pendingLogs",
    {
      "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "topics": [
        "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef"
      ]
    }
  ]
}