Glean MCP Server

import { describe, it, expect, beforeEach, afterEach } from 'vitest'; import { Logger, debug, trace, error, LogLevel } from '../../log/logger.js'; import fs from 'node:fs'; import path from 'node:path'; import os from 'node:os'; // Helper to sanitize timestamps and stack traces in log output for snapshotting function sanitizeLogOutput(log: string): string { // Replace ISO timestamps in brackets with [<TIMESTAMP>] let sanitized = log.replace( /\[\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}\.\d{3}Z\]/g, '[<TIMESTAMP>]', ); // Replace stack traces (Error: ... and following indented lines) with <STACK_TRACE> sanitized = sanitized.replace( /(Error: [^\n]+\n)([ ]+at [^\n]+\n?)+/g, 'Error: <STACK_TRACE>\n', ); return sanitized; } // Helper to get the log file path in the temp XDG state dir function getLogFilePath(tmpDir: string, appName = 'glean') { return path.join(tmpDir, appName, 'mcp.log'); } describe('Logger (file output, XDG, fixturify)', () => { let tmpDir: string; let originalXdgStateHome: string | undefined; beforeEach(() => { // Create a temp directory and set XDG_STATE_HOME tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), 'logger-test-')); originalXdgStateHome = process.env.XDG_STATE_HOME; process.env.XDG_STATE_HOME = tmpDir; Logger.reset(); }); afterEach(() => { // Restore XDG_STATE_HOME and clean up temp dir if (originalXdgStateHome) { process.env.XDG_STATE_HOME = originalXdgStateHome; } else { delete process.env.XDG_STATE_HOME; } fs.rmSync(tmpDir, { recursive: true, force: true }); }); it('writes debug, trace, and error messages to the log file at TRACE level', () => { const logger = Logger.getInstance(); logger.setLogLevel(LogLevel.TRACE); debug('debug message'); trace('trace message'); error('error message'); const logFilePath = getLogFilePath(tmpDir); const logContent = fs.readFileSync(logFilePath, 'utf8'); expect(sanitizeLogOutput(logContent)).toMatchInlineSnapshot(` "[<TIMESTAMP>] [DEBUG] debug message [<TIMESTAMP>] [TRACE] trace message [<TIMESTAMP>] [ERROR] error message " `); }); it('does not write debug or trace at ERROR level, but writes error', () => { const logger = Logger.getInstance(); logger.setLogLevel(LogLevel.ERROR); debug('debug message'); trace('trace message'); error('error message'); const logFilePath = getLogFilePath(tmpDir); const logContent = fs.readFileSync(logFilePath, 'utf8'); expect(sanitizeLogOutput(logContent)).toMatchInlineSnapshot(` "[<TIMESTAMP>] [ERROR] error message " `); }); it('writes debug but not trace at DEBUG level', () => { const logger = Logger.getInstance(); logger.setLogLevel(LogLevel.DEBUG); debug('debug message'); trace('trace message'); error('error message'); const logFilePath = getLogFilePath(tmpDir); const logContent = fs.readFileSync(logFilePath, 'utf8'); expect(sanitizeLogOutput(logContent)).toMatchInlineSnapshot(` "[<TIMESTAMP>] [DEBUG] debug message [<TIMESTAMP>] [ERROR] error message " `); }); it('writes only error at ERROR level', () => { const logger = Logger.getInstance(); logger.setLogLevel(LogLevel.ERROR); debug('debug message'); trace('trace message'); error('error message'); const logFilePath = getLogFilePath(tmpDir); const logContent = fs.readFileSync(logFilePath, 'utf8'); expect(sanitizeLogOutput(logContent)).toMatchInlineSnapshot(` "[<TIMESTAMP>] [ERROR] error message " `); }); it('logs Error objects with name, message, and stack trace', () => { const logger = Logger.getInstance(); logger.setLogLevel(LogLevel.TRACE); const err = new Error('something went wrong'); error('an error occurred', err); const logFilePath = getLogFilePath(tmpDir); const logContent = fs.readFileSync(logFilePath, 'utf8'); expect(sanitizeLogOutput(logContent)).toMatchInlineSnapshot(` "[<TIMESTAMP>] [ERROR] an error occurred [Error: something went wrong] Error: <STACK_TRACE> " `); }); it('logs non-Error objects as JSON', () => { const logger = Logger.getInstance(); logger.setLogLevel(LogLevel.TRACE); debug('object log', { foo: 'bar', baz: 42 }); const logFilePath = getLogFilePath(tmpDir); const logContent = fs.readFileSync(logFilePath, 'utf8'); expect(sanitizeLogOutput(logContent)).toMatchInlineSnapshot(` "[<TIMESTAMP>] [DEBUG] object log {"foo":"bar","baz":42} " `); }); it('logs Error objects with nested causes', () => { const logger = Logger.getInstance(); logger.setLogLevel(LogLevel.TRACE); const root = new Error('root cause'); const mid = new Error('mid cause'); (mid as any).cause = root; const top = new Error('top level'); (top as any).cause = mid; error('error with causes', top); const logFilePath = getLogFilePath(tmpDir); const logContent = fs.readFileSync(logFilePath, 'utf8'); expect(sanitizeLogOutput(logContent)).toMatchInlineSnapshot(` "[<TIMESTAMP>] [ERROR] error with causes [Error: top level] Error: <STACK_TRACE> Caused by: [Error: mid cause] Caused by: [Error: root cause] " `); }); });