winston
| Property | Value |
|---|---|
| Package | winston |
| Versions Covered | >=3.0.0 <4.0.0 |
| Contract Version | 1.0.0 |
| Status | production |
| Last Verified | 2026-02-26 |
| Maintainer | corpus-team |
Installation
npm install winston
Covered Functions
This contract covers 2 function(s):
createLogger()
Creates a logger instance
Import:
import { createLogger } from 'winston';
Postconditions
What happens after calling this function:
⚠️ WARNING - logger-transport-errors
Condition: transport fails (file write error, network error, permission denied)
Returns:
logger instance that silently fails without error listener
Required Handling:
Caller MUST attach 'error' event listener to logger and transports to handle transport failures. Without listener, errors are silently ignored and logs may be lost.
📖 Source
log()
Logs a message
Import:
import { log } from 'winston';
Postconditions
What happens after calling this function:
⚠️ WARNING - log-transport-failure
Condition: transport fails during log write (file system full, network down, permissions)
Returns:
void (operation may fail silently)
Required Handling:
Caller MUST attach 'error' event listener to logger to detect transport failures. Use logger.on('error', handler) to prevent silent log loss.
📖 Source