debug_traceCall

Note

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

Warning

Fee fields at latest and pending

At latest and pending this method prices the call against the block header’s base fee, not the worker’s current epoch base fee that eth_call and eth_estimateGas use. A request that sets gasPrice, maxFeePerGas or maxPriorityFeePerGas can therefore be accepted by eth_call and rejected here, or the reverse; requests without fee fields are unaffected. Tracked in #1587.

Runs a call as eth_call does, without creating a transaction, and returns the trace the chosen tracer builds. Without txIndex the call runs on the state after the given block. With txIndex the node starts from the block’s parent state, applies the block’s pre-transaction system calls, replays the block’s transactions before that index, and runs the call on top.

Parameters

Object - The transaction call object:

• from: DATA, 20 bytes - (optional) The address the call is sent from.
• to: DATA, 20 bytes - The address the call is directed to.
• gas: QUANTITY - (optional) Hexadecimal value of the gas provided for the call.
• gasPrice: QUANTITY - (optional) Hexadecimal value of the gasPrice used for each paid gas.
• maxPriorityFeePerGas: QUANTITY - (optional) Hexadecimal maximum fee, in Wei, the sender is willing to pay per gas above the base fee.
• maxFeePerGas: QUANTITY - (optional) Hexadecimal maximum total fee (base fee + priority fee), in Wei, the sender is willing to pay per gas.
• value: QUANTITY - (optional) Hexadecimal of the value sent with the call.
• data: DATA - (optional) Hash of the method signature and encoded parameters. See Ethereum contract ABI specification.

block parameter: QUANTITY|TAG|DATA - (optional) Hexadecimal block number, or one of the string tags latest, pending, earliest, safe, or finalized; a 32-byte block hash is also accepted. See the default block parameter. Defaults to latest.

Object - (optional) The tracing options: the fields debug_traceTransaction takes (tracer, tracerConfig, enableMemory, disableStack, disableStorage, enableReturnData), plus:

• stateOverrides: Object - (optional) Account overrides applied before the call, keyed by address, each with any of balance, nonce, code, and state or stateDiff.
• blockOverrides: Object - (optional) Block environment overrides, such as number, time, gasLimit, coinbase and baseFee.
• txIndex: QUANTITY - (optional) Run the call on the state just before the block’s transaction at this index. An index at or past the block’s transaction count fails with error -32602 tx_index <index> out of bounds for block with <count> transactions.

Returns

Object - The tracer’s output for the call, in the shapes debug_traceTransaction describes.

Example

Request

curl http://localhost:8545 \
 -X POST \
 -H "Content-Type: application/json" \
 --data '{"jsonrpc":"2.0","method":"debug_traceCall","params":[{
  "from":"0xb14d3c4f5fbfbcfb98af2d330000d49c95b93aa7",
  "to":"0x0000000000000000000000000000000000000000",
  "gas":"0x5208",
  "value":"0x64"},
  "latest",
  {"tracer":"callTracer"}],"id":1}'

Result

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "from": "0xb14d3c4f5fbfbcfb98af2d330000d49c95b93aa7",
    "gas": "0x5208",
    "gasUsed": "0x5208",
    "to": "0x0000000000000000000000000000000000000000",
    "input": "0x",
    "value": "0x64",
    "type": "CALL"
  }
}

source