@aitc/logger

AITC logging utility with requestId and service name support. Built on winston with customizable transports.

Installation

``bash
npm install @aitc/logger
`

Quick Start

`javascript
const { createLogger } = require("@aitc/logger");

const logger = createLogger({
level: process.env.LOG_LEVEL || "info",
service: "property-service",
transports: ["console", "file"],
logDir: __dirname,
});

// Use the logger
logger.info("Application started", { requestId: "abc123" });
logger.error("Something went wrong", { error: error.message, requestId: "abc123" });
`

Configuration Options

$3

Creates a logger instance with the following options:

| Option | Type | Default | Description |
|--------|------|---------|-------------|
| level | string | process.env.LOG_LEVEL \|\| "info" | Log level (info, error, warn, debug) |
| service | string | null | Service name to include in logs |
| transports | Array | ["console"] | Transport types: "console", "file" |
| logDir | string | process.cwd() | Directory for log files (only if file transport enabled) |
| errorLogFile | string | "error.log" | Error log filename |
| combinedLogFile | string | "combined.log" | Combined log filename |

Usage Examples

$3

`javascript
const { createLogger } = require("@aitc/logger");

const logger = createLogger({
level: "info",
service: "my-service",
});

logger.info("User logged in", { userId: 123, requestId: "req-456" });
logger.error("Database connection failed", { error: err.message, requestId: "req-456" });
`

$3

`javascript
const { createLogger } = require("@aitc/logger");
const path = require("path");

const logger = createLogger({
level: process.env.LOG_LEVEL || "info",
service: "property-service",
transports: ["console", "file"],
logDir: path.join(__dirname, "logs"),
errorLogFile: "error.log",
combinedLogFile: "combined.log",
});
`

$3

`javascript
const { createLogger } = require("@aitc/logger");

// LOG_LEVEL is automatically read from process.env
const logger = createLogger({
service: "auth-service",
transports: ["console"],
});
`

$3

If you're migrating from the old logger that used a config file:

Before:
`javascript
const logger = require("../utils/logger");
const config = require("../config/config");
`

After:
`javascript
const { createLogger } = require("@aitc/logger");
const config = require("../config/config");

const logger = createLogger({
level: config.log_level || process.env.LOG_LEVEL || "info",
service: "property-service",
transports: ["console", "file"],
logDir: __dirname,
});
`

API

$3

Parameters:
- message (string): Log message
- meta (object): Metadata object. Special fields:
- requestId: Request ID to include in log
- service: Service name (overrides default service)
- Any other fields will be JSON stringified

$3

Logs are formatted as:
`
YYYY-MM-DD HH:mm:ss [LEVEL] [service-name] [request-id: requestId] message {metadata}
`

Example:
`
2026-01-09 12:30:45 [INFO] [property-service] [request-id: abc123] User logged in {"userId":123}
`

Environment Variables

- LOG_LEVEL`: Sets the default log level (info, error, warn, debug)

License

ISC

Support

For issues and questions, please contact the AITC development team.