MCP Time Server Node

#!/usr/bin/env node /** * Research script to verify system timezone detection behavior * This will help us understand how to properly implement the feature */ console.log('=== System Timezone Detection Research ===\n'); // Test 1: Basic Intl.DateTimeFormat behavior console.log('1. Basic Intl.DateTimeFormat().resolvedOptions().timeZone:'); try { const systemTimezone = Intl.DateTimeFormat().resolvedOptions().timeZone; console.log(` Result: "${systemTimezone}"`); console.log(` Type: ${typeof systemTimezone}`); console.log(` Valid: ${systemTimezone && systemTimezone.length > 0}\n`); } catch (error) { console.log(` ERROR: ${error.message}\n`); } // Test 2: Node.js version compatibility console.log('2. Node.js version:'); console.log(` Version: ${process.version}`); console.log(` Platform: ${process.platform}\n`); // Test 3: Environment variable behavior console.log('3. Environment variable testing:'); // Test undefined delete process.env.DEFAULT_TIMEZONE; console.log(` DEFAULT_TIMEZONE undefined: ${process.env.DEFAULT_TIMEZONE}`); console.log(` Type: ${typeof process.env.DEFAULT_TIMEZONE}`); // Test empty string process.env.DEFAULT_TIMEZONE = ''; console.log(` DEFAULT_TIMEZONE empty: "${process.env.DEFAULT_TIMEZONE}"`); console.log(` Type: ${typeof process.env.DEFAULT_TIMEZONE}`); // Test valid timezone process.env.DEFAULT_TIMEZONE = 'America/New_York'; console.log(` DEFAULT_TIMEZONE valid: "${process.env.DEFAULT_TIMEZONE}"`); // Test invalid timezone process.env.DEFAULT_TIMEZONE = 'Invalid/Zone'; console.log(` DEFAULT_TIMEZONE invalid: "${process.env.DEFAULT_TIMEZONE}"\n`); // Test 4: Timezone validation with date-fns-tz console.log('4. Timezone validation with date-fns-tz:'); const { getTimezoneOffset } = require('date-fns-tz'); function isValidTimezone(tz) { try { const offset = getTimezoneOffset(tz, new Date()); return !isNaN(offset); } catch (e) { return false; } } const testTimezones = [ Intl.DateTimeFormat().resolvedOptions().timeZone, 'America/New_York', 'Invalid/Zone', '', undefined, null, ]; testTimezones.forEach((tz) => { console.log(` "${tz}": ${isValidTimezone(tz) ? 'valid' : 'invalid'}`); }); // Test 5: Precedence logic simulation console.log('\n5. Precedence logic simulation:'); function getDefaultTimezone(paramTimezone, envTimezone, systemTimezone) { // Parameter takes precedence (but empty string means UTC for backward compatibility) if (paramTimezone !== undefined) { return paramTimezone === '' ? 'UTC' : paramTimezone; } // Environment variable next if (envTimezone && envTimezone !== '' && isValidTimezone(envTimezone)) { return envTimezone; } // System timezone if (systemTimezone && isValidTimezone(systemTimezone)) { return systemTimezone; } // Final fallback return 'UTC'; } const systemTz = Intl.DateTimeFormat().resolvedOptions().timeZone; const scenarios = [ { param: 'Asia/Tokyo', env: 'America/New_York', expected: 'Asia/Tokyo' }, { param: undefined, env: 'America/New_York', expected: 'America/New_York' }, { param: undefined, env: undefined, expected: systemTz }, { param: undefined, env: 'Invalid/Zone', expected: systemTz }, { param: '', env: 'America/New_York', expected: 'UTC' }, // Backward compatibility { param: undefined, env: '', expected: systemTz }, ]; scenarios.forEach(({ param, env, expected }) => { const result = getDefaultTimezone(param, env, systemTz); console.log(` param="${param}", env="${env}" => "${result}" (expected: "${expected}")`); }); // Test 6: Edge cases console.log('\n6. Edge cases:'); // Test with TZ environment variable (common on Unix systems) const originalTZ = process.env.TZ; process.env.TZ = 'America/Chicago'; console.log(` With TZ=America/Chicago: ${Intl.DateTimeFormat().resolvedOptions().timeZone}`); delete process.env.TZ; console.log(` Without TZ: ${Intl.DateTimeFormat().resolvedOptions().timeZone}`); if (originalTZ) process.env.TZ = originalTZ; // Test 7: Performance check console.log('\n7. Performance check:'); const iterations = 10000; console.time(' Intl.DateTimeFormat resolution'); for (let i = 0; i < iterations; i++) { Intl.DateTimeFormat().resolvedOptions().timeZone; } console.timeEnd(' Intl.DateTimeFormat resolution'); console.time(' Cached access'); const cachedTz = Intl.DateTimeFormat().resolvedOptions().timeZone; for (let i = 0; i < iterations; i++) { const tz = cachedTz; } console.timeEnd(' Cached access'); console.log('\n=== Research Complete ===');