Fuel TS SDK

⌘K

Logs

Icon LinkWorking with Script Logs

When you log a value within a script, you can generates a log entry that is added to the log receipt, and the variable type is recorded in the script's ABI. The SDK enables you to parse these values into TypeScript types.

Icon LinkSimple

Consider the following example script:

script;
 
fn main(log_value: str[7]) -> str[7] {
    log(log_value);
    log_value
}

To access the logged values in TypeScript, use the logs property in the response of a script call.

import { Provider, Wallet } from 'fuels';
 
import { WALLET_PVT_KEY, LOCAL_NETWORK_URL } from '../../../env';
import { ScriptLogSimple } from '../../../typegend';
 
const provider = new Provider(LOCAL_NETWORK_URL);
const wallet = Wallet.fromPrivateKey(WALLET_PVT_KEY, provider);
 
const script = new ScriptLogSimple(wallet);
const { waitForResult } = await script.functions.main('ScriptA').call();
 
const { logs } = await waitForResult();
// logs: ['ScriptA']

Icon LinkGrouped logs

Consider the following example script:

script;
 
use log_simple_abi::LogSimple;
 
fn main(contract_id: b256) {
    log("Script started");
 
    let log_contract = abi(LogSimple, contract_id);
    log_contract.log_simple(__to_str_array("ContractA"));
 
    log("Script finished");
}

Icon LinkWith Contract

To access the fine-grained logs for each contract, use the groupedLogs property from the script call response.

import { Provider, Wallet, ZeroBytes32 } from 'fuels';
 
import { WALLET_PVT_KEY, LOCAL_NETWORK_URL } from '../../../env';
import { LogSimpleFactory, ScriptLogWithContract } from '../../../typegend';
 
const provider = new Provider(LOCAL_NETWORK_URL);
const wallet = Wallet.fromPrivateKey(WALLET_PVT_KEY, provider);
 
// Create a contract instance
const { waitForResult: waitForDeploy } = await LogSimpleFactory.deploy(wallet);
const { contract } = await waitForDeploy();
 
// Create a script instance
const script = new ScriptLogWithContract(wallet);
 
// Call the script
const { waitForResult } = await script.functions
  .main(contract.id.toB256())
  .addContracts([contract])
  .call();
 
// Wait for the script to finish and get the logs
const { groupedLogs } = await waitForResult();
// groupedLogs = {
//   [ZeroBytes32]: ['Script started', 'Script finished'],
//   [contract.id.toB256()]: ['ContractA', 'ContractB'],
// }

Although Scripts don't have IDs/addresses, they can still call contracts and generate logs, so we use a zeroed-out (hexadecimal) address as their key instead.