trace_get

Note

Served only when trace is named in --http.api or --ws.api; see Enabling Namespaces.

Returns one Parity-style trace of a mined transaction, selected by its index in the list trace_transaction returns: index 0 is the top-level call. The node traces the whole transaction to answer, so the cost is the same as trace_transaction.

Traces cover the block’s transactions only. The system calls a block runs before its transactions (EIP-4788 beacon root, EIP-2935 block hashes) and the epoch-closing system calls (applyIncentives and concludeEpoch) are not transactions, so no tracer shows them.

Parameters

DATA, 32 Bytes - The transaction hash.

Array - The trace index, as a one-element list. Each index may be a hex string ("0x0"), a decimal string or a JSON number. Only one index is supported: a list with no index or with more than one returns null.

Returns

Object - The trace at that index, or null when the node does not know the transaction, when the index is past the transaction’s last trace, or when the list does not hold exactly one index:

action: Object - What the frame did. For a call: from (DATA, 20 bytes, the caller), callType (call, callcode, delegatecall or staticcall), gas (QUANTITY, the gas available to the frame), input (DATA), to (DATA, 20 bytes) and value (QUANTITY, in wei). For a create: from, gas, init (DATA, the init code), value and creationMethod (create or create2). For a suicide (a SELFDESTRUCT): address, balance and refundAddress. The top-level frame’s gas is the transaction’s gas limit minus its intrinsic gas, so it is 0x0 for a plain transfer sent with a 21,000 gas limit.
blockHash: DATA, 32 Bytes - Hash of the block that holds the transaction.
blockNumber: Number - Number of that block, as a JSON number rather than a hex string.
error: String - The error the frame failed with. Absent when the frame succeeded.
result: Object - The frame’s outcome. For a call: gasUsed (QUANTITY) and output (DATA). For a create: address (DATA, 20 bytes, the new contract), code (DATA, the deployed code) and gasUsed. null for a suicide, and can be null for a frame that failed. The top-level frame’s gasUsed leaves out the intrinsic gas, so it is 0x0 for a plain transfer.
subtraces: Number - How many frames this frame called directly.
traceAddress: Array - The frame’s path in the call tree, as JSON numbers: [] for the top-level frame, [0] for its first child, [0, 1] for that child’s second child.
transactionHash: DATA, 32 Bytes - Hash of the transaction.
transactionPosition: Number - The transaction’s index in the block, as a JSON number.
type: String - The kind of frame: call, create or suicide.

Example

Request

curl http://localhost:8545 \
 -X POST \
 -H "Content-Type: application/json" \
 --data '{"jsonrpc":"2.0","method":"trace_get","params":["0xa794c7eb915c26fdb77242159053c1a36241bcd016b671fb07abe3fa9050805e",["0x0"]],"id":1}'

Result

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "action": {
      "from": "0xb14d3c4f5fbfbcfb98af2d330000d49c95b93aa7",
      "callType": "call",
      "gas": "0x0",
      "input": "0x",
      "to": "0x0000000000000000000000000000000000000000",
      "value": "0x64"
    },
    "blockHash": "0x1e0ed1376b6f8cc5deb9749a96c1207765ae9cd09ff46fe6200ca5b3f2913e8f",
    "blockNumber": 1,
    "result": {
      "gasUsed": "0x0",
      "output": "0x"
    },
    "subtraces": 0,
    "traceAddress": [],
    "transactionHash": "0xa794c7eb915c26fdb77242159053c1a36241bcd016b671fb07abe3fa9050805e",
    "transactionPosition": 0,
    "type": "call"
  }
}