import pino from 'pino';
import * as fs from 'fs';
import * as path from 'path';
import * as os from 'os';
// Log file path - write to temp directory
const logFilePath = path.join(os.tmpdir(), 'alko-mcp.log');
// Create a write stream for file logging
const logFileStream = fs.createWriteStream(logFilePath, { flags: 'a' });
/**
* Application logger using pino
* IMPORTANT: Writes to stderr AND a log file for debugging
* MCP uses stdout for JSON-RPC communication, so all logs must go to stderr
*/
const pinoLogger = pino(
{
level: process.env.LOG_LEVEL || 'info',
},
// Write to multiple destinations: stderr and log file
pino.multistream([
{ stream: pino.destination(2) }, // stderr
{ stream: logFileStream }, // log file
])
);
// Log the log file location on startup
pinoLogger.info(`Log file: ${logFilePath}`);
/**
* Simplified logger wrapper with consistent API
*/
export const logger = {
info: (msg: string, obj?: Record<string, unknown>) => {
if (obj) {
pinoLogger.info(obj, msg);
} else {
pinoLogger.info(msg);
}
},
error: (msg: string, obj?: Record<string, unknown>) => {
if (obj) {
pinoLogger.error(obj, msg);
} else {
pinoLogger.error(msg);
}
},
warn: (msg: string, obj?: Record<string, unknown>) => {
if (obj) {
pinoLogger.warn(obj, msg);
} else {
pinoLogger.warn(msg);
}
},
debug: (msg: string, obj?: Record<string, unknown>) => {
if (obj) {
pinoLogger.debug(obj, msg);
} else {
pinoLogger.debug(msg);
}
},
};
/**
* Create a child logger with additional context
*/
export function createLogger(context: Record<string, unknown>) {
return pinoLogger.child(context);
}
