Metabase MCP Server

/** * Simple structured logger for the MCP server */ export class Logger { constructor(context = 'MetabaseMCP') { this.context = context; this.logLevel = process.env.LOG_LEVEL || 'info'; } /** * Log levels in order of severity */ static LEVELS = { debug: 0, info: 1, warn: 2, error: 3, }; /** * Check if a log level should be logged */ shouldLog(level) { const currentLevel = Logger.LEVELS[this.logLevel] || Logger.LEVELS.info; const messageLevel = Logger.LEVELS[level] || Logger.LEVELS.info; return messageLevel >= currentLevel; } /** * Format and output a log entry */ log(level, message, meta = {}) { const logEntry = { timestamp: new Date().toISOString(), level: level.toUpperCase(), context: this.context, message, ...meta, }; // Use console.error for all logs to avoid interfering with MCP stdio console.error(JSON.stringify(logEntry)); } /** * Debug level logging */ debug(message, meta = {}) { if (this.shouldLog('debug')) { this.log('debug', message, meta); } } /** * Info level logging */ info(message, meta = {}) { if (this.shouldLog('info')) { this.log('info', message, meta); } } /** * Warning level logging */ warn(message, meta = {}) { if (this.shouldLog('warn')) { this.log('warn', message, meta); } } /** * Error level logging */ error(message, error = null, meta = {}) { if (this.shouldLog('error')) { const errorMeta = error ? { error: { message: error.message, code: error.code, stack: error.stack, }, } : {}; this.log('error', message, { ...meta, ...errorMeta }); } } /** * Create a child logger with a different context */ child(context) { return new Logger(`${this.context}:${context}`); } } // Export a default logger instance export const logger = new Logger();