debug_traceBlockByHash | Arbitrum

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Parameters

• hash — the hash of the block to be traced.
• tracer — an object identifying the type of tracer and its configuration:
  • 4byteTracer — tracer that captures the function signatures and call data sizes for all functions executed during a transaction, creating a map that links each selector and size combination to the number of times it occurred.
  • callTracer — tracer that captures information on all call frames executed during a transaction. The resulting nested list of call frames is organized into a tree structure that reflects the way the EVM works and can be used for debugging and analysis purposes.
  • prestateTracer — tracer with two modes: prestate and diff, where the former returns the accounts needed to execute a transaction, and the latter returns the differences between the pre and post-states of the transaction.

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Response types

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4byteTracer response

• object — the 4byteTracer traces object:
  • result — a map of the function signature, the call data size, and how many times the function was called.

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callTracer response

• object — the callTracer traces object:
  • from — the address of the sender who initiated the transaction.
  • gas — the units of gas included in the transaction by the sender.
  • gasUsed — the total used gas by the call, encoded as hexadecimal.
  • to — the address of the recipient of the transaction if it was a transaction to an address. For contract creation transactions, this field is null.
  • input — the optional input data sent with the transaction.
  • output — the return value of the call, encoded as a hexadecimal string.
  • error — an error message in case the execution failed.
  • revertReason — the reason why the transaction was reverted, returned by the smart contract if any.
  • calls — a list of sub-calls made by the contract during the call, each represented as a nested call frame object.

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prestateTracer response

• object — the prestateTracer traces object:
  • smart contract address — the address of the smart contract associated with the result.
    • balance — the balance of the contract, expressed in Wei and encoded as a hexadecimal string.
    • code — the bytecode of the contract, encoded as a hexadecimal string.
    • nonce — the nonce of the account associated with the contract, represented as an unsigned integer.
    • storage — a map of key-value pairs representing the storage slots of the contract.

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debug_traceBlockByHash code examples

const ethers = require('ethers');
const NODE_URL = "YOUR_CHAINSTACK_ENDPOINT";
const provider = new ethers.JsonRpcProvider(NODE_URL);

const traceBlockByHash = async (blockHash) => {
  const tracer = { tracer: "callTracer" };
  const traces = await provider.send("debug_traceBlockByHash", [blockHash, tracer]);
  console.log(traces);
};

traceBlockByHash("0xb3a662bef958318d25b80ba2ce6932d7e2f10262086247fa848f2d96de75fa18");

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Use case