Update version to 0.0.16, add Appender and AppenderFactory classes, refactor LoggerFactory methods, and implement logging functionality with tests.

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@techniker-me/logger",
-  "version": "0.0.15",
+  "version": "0.0.16",
   "description": "A logger package for logging",
   "type": "module",
   "types": "./dist/types/index.d.ts",

src/LoggerFactory.ts

@@ -27,7 +27,7 @@ export default class LoggerFactory {
     return LoggerFactory._loggers.get(category) as Logger;
   }
 
-  public static applyApppender(appender: IAppender): Disposable {
+  public static applyAppender(appender: IAppender): Disposable {
     LoggerFactory._appenders.add(appender);
 
     return new Disposable(() => LoggerFactory._appenders.delete(appender));
@@ -40,10 +40,10 @@ export default class LoggerFactory {
   }
 
   private static applyConsoleAppender(): void {
-    LoggerFactory.applyApppender(new ConsoleAppender());
+    LoggerFactory.applyAppender(new ConsoleAppender());
   }
 
   private static applyRemoteAppender(): void {
-    LoggerFactory.applyApppender(new TechnikerMeAppender());
+    LoggerFactory.applyAppender(new TechnikerMeAppender());
   }
 }

src/appenders/Appender.ts

@@ -0,0 +1,62 @@
+import {LoggingLevelType} from '../level/LoggingLevel';
+import ILogMessage from './LogMessage';
+
+export type AppenderOptions = {
+  domain?: string;
+};
+
+export default class Appender {
+  private readonly _logRecorderUrl: string = 'https://logserver.techniker.me/api/logs';
+  private readonly _domain: string = typeof window !== 'undefined' ? (window.location?.hostname ?? '') : '';
+  private readonly _logMessageQueue: ILogMessage[] = [];
+  private _pendingPostLogMessagePromise: Promise<Response | undefined> | undefined = undefined;
+
+  constructor(logRecorderUrl: string, {domain}: AppenderOptions) {
+    this._logRecorderUrl = logRecorderUrl;
+    this._domain = domain ?? this._domain;
+  }
+
+  public log(timestamp: string, level: LoggingLevelType, category: string, message: string): void {
+    const logMessage = {
+      timestamp,
+      domain: this._domain,
+      level,
+      category,
+      message
+    };
+    this.queueMessage(logMessage);
+    this.postLogMessage();
+  }
+
+  private async postLogMessage(): Promise<void> {
+    const logMessage = this._logMessageQueue.shift();
+
+    if (!logMessage || this._pendingPostLogMessagePromise !== undefined) {
+      return;
+    }
+
+    try {
+      if (typeof fetch === 'undefined') {
+        console.error('Fetch API is not available in this environment');
+        return;
+      }
+
+      this._pendingPostLogMessagePromise = fetch(this._logRecorderUrl, {
+        headers: {
+          'Content-Type': 'application/json',
+          Accept: 'application/json'
+        },
+        mode: 'no-cors',
+        method: 'POST',
+        body: JSON.stringify(logMessage)
+      }).then(() => (this._pendingPostLogMessagePromise = undefined));
+    } catch (e) {
+      console.error('Unable to send logs due to [%o]', e);
+      return;
+    }
+  }
+
+  private queueMessage(logMessage: ILogMessage): void {
+    this._logMessageQueue.push(logMessage);
+  }
+}

src/appenders/AppenderFactory.ts

@@ -0,0 +1,12 @@
+import {AppenderOptions} from './Appender';
+import Appender from './Appender';
+
+export default class AppnederFactory {
+  public static createRemoteAppender(remoteAppenderUrl: string, {domain}: AppenderOptions): Appender {
+    return new Appender(remoteAppenderUrl, {domain});
+  }
+
+  private constructor() {
+    throw new Error('AppenderFactory is a static class that may not be instantiated');
+  }
+}

src/appenders/LogMessage.ts

@@ -0,0 +1,6 @@
+export default interface ILogMessage {
+  timestamp: string;
+  level: string;
+  category: string;
+  message: string;
+}

src/index.ts

@@ -1,8 +1,9 @@
 import type ILogger from './ILogger';
 import type IAppender from './appenders/IAppender';
+import AppenderFactory from './appenders/AppenderFactory';
 import LoggerFactory from './LoggerFactory';
 import LoggingLevelMapping from './level/LoggingLevelMapping';
 
 export type {ILogger, IAppender};
-export {LoggerFactory, LoggingLevelMapping};
-export default {LoggerFactory, LoggingLevelMapping};
+export {AppenderFactory, LoggerFactory, LoggingLevelMapping};
+export default {AppenderFactory, LoggerFactory, LoggingLevelMapping};

src/level/LoggingLevel.ts

@@ -1,12 +1,12 @@
 export enum LoggingLevel {
   Off = -1,
-  Info = 10,
-  Warn = 20,
-  Error = 30,
-  Debug = 40,
-  Trace = 50,
-  Silly = 60,
-  All = 100
+  Debug = 10,
+  Trace = 20,
+  Silly = 30,
+  Info = 40,
+  Warn = 50,
+  Error = 60,
+  All = 70
 }
 
-export type LoggingLevelType = 'Off' | 'Info' | 'Warn' | 'Error' | 'Debug' | 'Trace' | 'Silly' | 'All';
+export type LoggingLevelType = 'Off' | 'Debug' | 'Trace' | 'Info' | 'Silly' | 'Warn' | 'Error' | 'All';

src/level/Threshold.ts

@@ -3,7 +3,7 @@ import Defaults from '../Defaults';
 import {LoggingLevel} from './LoggingLevel';
 
 class Threshold {
-  private _threshold: Subject<LoggingLevel> = new Subject(LoggingLevel.Debug);
+  private _threshold: Subject<LoggingLevel> = new Subject(LoggingLevel.Info);
 
   constructor(loggingLevel?: LoggingLevel) {
     this._threshold = new Subject(loggingLevel ?? Defaults.loggingLevel);

tests/ConsoleAppender.test.ts

@@ -0,0 +1,78 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from 'bun:test';
+import ConsoleAppender from '../src/appenders/ConsoleAppender';
+import { LoggingLevel } from '../src/level/LoggingLevel';
+
+describe('ConsoleAppender', () => {
+  let consoleAppender: ConsoleAppender;
+  let mockConsoleLog: any;
+  let mockConsoleError: any;
+
+  beforeEach(() => {
+    consoleAppender = new ConsoleAppender();
+
+    // Mock console methods
+    mockConsoleLog = vi.spyOn(console, 'log').mockImplementation(() => {});
+    mockConsoleError = vi.spyOn(console, 'error').mockImplementation(() => {});
+  });
+
+  afterEach(() => {
+    mockConsoleLog.mockRestore();
+    mockConsoleError.mockRestore();
+  });
+
+  it('should log info messages to console.log', () => {
+    consoleAppender.log('2023-01-01T00:00:00.000Z', 'Info', 'test-category', 'info message');
+
+    expect(mockConsoleLog).toHaveBeenCalledWith('2023-01-01T00:00:00.000Z [Info] [test-category] info message');
+    expect(mockConsoleError).not.toHaveBeenCalled();
+  });
+
+  it('should log debug messages to console.log', () => {
+    consoleAppender.log('2023-01-01T00:00:00.000Z', 'Debug', 'test-category', 'debug message');
+
+    expect(mockConsoleLog).toHaveBeenCalledWith('2023-01-01T00:00:00.000Z [Debug] [test-category] debug message');
+    expect(mockConsoleError).not.toHaveBeenCalled();
+  });
+
+  it('should log trace messages to console.log', () => {
+    consoleAppender.log('2023-01-01T00:00:00.000Z', 'Trace', 'test-category', 'trace message');
+
+    expect(mockConsoleLog).toHaveBeenCalledWith('2023-01-01T00:00:00.000Z [Trace] [test-category] trace message');
+    expect(mockConsoleError).not.toHaveBeenCalled();
+  });
+
+  it('should log silly messages to console.log', () => {
+    consoleAppender.log('2023-01-01T00:00:00.000Z', 'Silly', 'test-category', 'silly message');
+
+    expect(mockConsoleLog).toHaveBeenCalledWith('2023-01-01T00:00:00.000Z [Silly] [test-category] silly message');
+    expect(mockConsoleError).not.toHaveBeenCalled();
+  });
+
+  it('should log warn messages to console.error', () => {
+    consoleAppender.log('2023-01-01T00:00:00.000Z', 'Warn', 'test-category', 'warn message');
+
+    expect(mockConsoleError).toHaveBeenCalledWith('2023-01-01T00:00:00.000Z [Warn] [test-category] warn message');
+    expect(mockConsoleLog).not.toHaveBeenCalled();
+  });
+
+  it('should log error messages to console.error', () => {
+    consoleAppender.log('2023-01-01T00:00:00.000Z', 'Error', 'test-category', 'error message');
+
+    expect(mockConsoleError).toHaveBeenCalledWith('2023-01-01T00:00:00.000Z [Error] [test-category] error message');
+    expect(mockConsoleLog).not.toHaveBeenCalled();
+  });
+
+  it('should log all messages to console.log', () => {
+    consoleAppender.log('2023-01-01T00:00:00.000Z', 'All', 'test-category', 'all message');
+
+    expect(mockConsoleLog).toHaveBeenCalledWith('2023-01-01T00:00:00.000Z [All] [test-category] all message');
+    expect(mockConsoleError).not.toHaveBeenCalled();
+  });
+
+  it('should not log off messages', () => {
+    consoleAppender.log('2023-01-01T00:00:00.000Z', 'Off', 'test-category', 'off message');
+
+    expect(mockConsoleLog).not.toHaveBeenCalled();
+    expect(mockConsoleError).not.toHaveBeenCalled();
+  });
+});

tests/Logger.test.ts

@@ -0,0 +1,227 @@
+import { describe, it, expect, beforeEach, vi, type Mock } from 'bun:test';
+import Logger from '../src/Logger';
+import { LoggingLevel } from '../src/level/LoggingLevel';
+import Threshold from '../src/level/Threshold';
+import type IAppender from '../src/appenders/IAppender';
+
+describe('Logger', () => {
+  let mockAppender: IAppender;
+  let threshold: Threshold;
+  let logger: Logger;
+
+  beforeEach(() => {
+    mockAppender = {
+      log: vi.fn(),
+    };
+
+    threshold = new Threshold(LoggingLevel.Info);
+    logger = new Logger('test-category', threshold, new Set([mockAppender]));
+  });
+
+  describe('threshold filtering', () => {
+    it('should log info messages when threshold is Info', () => {
+      logger.info('test message');
+
+      expect(mockAppender.log).toHaveBeenCalledWith(
+        expect.any(String), // timestamp
+        'Info',
+        'test-category',
+        'test message'
+      );
+    });
+
+    it('should log warn messages when threshold is Info', () => {
+      logger.warn('test message');
+
+      expect(mockAppender.log).toHaveBeenCalledWith(
+        expect.any(String),
+        'Warn',
+        'test-category',
+        'test message'
+      );
+    });
+
+    it('should log error messages when threshold is Info', () => {
+      logger.error('test message');
+
+      expect(mockAppender.log).toHaveBeenCalledWith(
+        expect.any(String),
+        'Error',
+        'test-category',
+        'test message'
+      );
+    });
+
+    it('should not log debug messages when threshold is Info', () => {
+      logger.debug('test message');
+
+      expect(mockAppender.log).not.toHaveBeenCalled();
+    });
+
+    it('should not log trace messages when threshold is Info', () => {
+      logger.trace('test message');
+
+      expect(mockAppender.log).not.toHaveBeenCalled();
+    });
+
+    it('should not log silly messages when threshold is Info', () => {
+      logger.silly('test message');
+
+      expect(mockAppender.log).not.toHaveBeenCalled();
+    });
+
+    it('should log all messages when threshold is Debug', () => {
+      threshold.value = LoggingLevel.Debug;
+
+      logger.debug('debug message');
+      logger.info('info message');
+      logger.warn('warn message');
+      logger.error('error message');
+
+      expect(mockAppender.log).toHaveBeenCalledTimes(4);
+    });
+
+    it('should log only error messages when threshold is Error', () => {
+      threshold.value = LoggingLevel.Error;
+
+      logger.error('error message');
+      logger.warn('warn message');
+      logger.info('info message');
+
+      expect(mockAppender.log).toHaveBeenCalledTimes(1);
+      expect(mockAppender.log).toHaveBeenCalledWith(
+        expect.any(String),
+        'Error',
+        'test-category',
+        'error message'
+      );
+    });
+  });
+
+  describe('message formatting', () => {
+    beforeEach(() => {
+      threshold.value = LoggingLevel.Debug; // Allow all messages for formatting tests
+    });
+
+    it('should format messages with %s placeholder', () => {
+      logger.info('Hello %s', 'world');
+
+      expect(mockAppender.log).toHaveBeenCalledWith(
+        expect.any(String),
+        'Info',
+        'test-category',
+        'Hello world'
+      );
+    });
+
+    it('should format messages with %d placeholder', () => {
+      logger.info('Count: %d', 42);
+
+      expect(mockAppender.log).toHaveBeenCalledWith(
+        expect.any(String),
+        'Info',
+        'test-category',
+        'Count: 42'
+      );
+    });
+
+    it('should format messages with %j placeholder', () => {
+      logger.info('Object: %j', { key: 'value' });
+
+      expect(mockAppender.log).toHaveBeenCalledWith(
+        expect.any(String),
+        'Info',
+        'test-category',
+        'Object: {"key":"value"}'
+      );
+    });
+
+    it('should handle circular references in %j placeholder', () => {
+      const obj: any = { key: 'value' };
+      obj.self = obj;
+
+      logger.info('Circular: %j', obj);
+
+      expect(mockAppender.log).toHaveBeenCalledWith(
+        expect.any(String),
+        'Info',
+        'test-category',
+        'Circular: [Circular]'
+      );
+    });
+
+    it('should handle multiple placeholders', () => {
+      logger.info('User %s has %d items: %j', 'Alice', 5, ['a', 'b']);
+
+      expect(mockAppender.log).toHaveBeenCalledWith(
+        expect.any(String),
+        'Info',
+        'test-category',
+        'User Alice has 5 items: ["a","b"]'
+      );
+    });
+
+    it('should handle more placeholders than arguments', () => {
+      logger.info('Hello %s %s', 'world');
+
+      expect(mockAppender.log).toHaveBeenCalledWith(
+        expect.any(String),
+        'Info',
+        'test-category',
+        'Hello world %s'
+      );
+    });
+
+    it('should handle fewer placeholders than arguments', () => {
+      logger.info('Hello %s', 'world', 'extra');
+
+      expect(mockAppender.log).toHaveBeenCalledWith(
+        expect.any(String),
+        'Info',
+        'test-category',
+        'Hello world'
+      );
+    });
+
+    it('should handle non-number values for %d', () => {
+      logger.info('Value: %d', 'not-a-number');
+
+      expect(mockAppender.log).toHaveBeenCalledWith(
+        expect.any(String),
+        'Info',
+        'test-category',
+        'Value: NaN'
+      );
+    });
+  });
+
+  describe('timestamp formatting', () => {
+    it('should include ISO timestamp in log messages', () => {
+      const before = new Date().toISOString();
+      logger.info('test');
+      const after = new Date().toISOString();
+
+      const call = (mockAppender.log as Mock).mock.calls[0];
+      const timestamp = call[0];
+
+      expect(timestamp).toBeDefined();
+      expect(() => new Date(timestamp)).not.toThrow();
+      expect(timestamp >= before || timestamp <= after).toBe(true);
+    });
+  });
+
+  describe('multiple appenders', () => {
+    it('should call all appenders', () => {
+      const mockAppender2: IAppender = {
+        log: vi.fn(),
+      };
+
+      const loggerWithMultiple = new Logger('test', threshold, new Set([mockAppender, mockAppender2]));
+
+      loggerWithMultiple.info('test message');
+
+      expect(mockAppender.log).toHaveBeenCalledTimes(1);
+      expect(mockAppender2.log).toHaveBeenCalledTimes(1);
+    });
+  });
+});

tests/LoggerFactory.test.ts

@@ -0,0 +1,94 @@
+import { describe, it, expect, beforeEach, vi } from 'bun:test';
+import LoggerFactory from '../src/LoggerFactory';
+import { LoggingLevel } from '../src/level/LoggingLevel';
+import type IAppender from '../src/appenders/IAppender';
+
+describe('LoggerFactory', () => {
+  let mockAppender: IAppender;
+
+  beforeEach(() => {
+    // Reset LoggerFactory state between tests
+    // Note: This is tricky since LoggerFactory uses static state
+    // In a real scenario, we'd need to refactor for better testability
+    mockAppender = {
+      log: vi.fn(),
+    };
+  });
+
+  describe('getLogger', () => {
+    it('should return a logger instance', () => {
+      const logger = LoggerFactory.getLogger('test-category');
+
+      expect(logger).toBeDefined();
+      expect(typeof logger.info).toBe('function');
+      expect(typeof logger.warn).toBe('function');
+      expect(typeof logger.error).toBe('function');
+      expect(typeof logger.debug).toBe('function');
+    });
+
+    it('should return the same logger instance for the same category', () => {
+      const logger1 = LoggerFactory.getLogger('test-category');
+      const logger2 = LoggerFactory.getLogger('test-category');
+
+      expect(logger1).toBe(logger2);
+    });
+
+    it('should return different logger instances for different categories', () => {
+      const logger1 = LoggerFactory.getLogger('category1');
+      const logger2 = LoggerFactory.getLogger('category2');
+
+      expect(logger1).not.toBe(logger2);
+    });
+  });
+
+  describe('setLoggingLevel', () => {
+    it('should change the logging threshold', () => {
+      LoggerFactory.setLoggingLevel('Debug');
+
+      // Create a logger and check that debug messages are logged
+      const logger = LoggerFactory.getLogger('test');
+      logger.debug('debug message');
+
+      // Note: We can't easily test this without mocking the appenders
+      // This would require refactoring LoggerFactory for better testability
+    });
+  });
+
+  describe('applyAppender', () => {
+    it('should return a disposable', () => {
+      const disposable = LoggerFactory.applyAppender(mockAppender);
+
+      expect(disposable).toBeDefined();
+      expect(typeof disposable.dispose).toBe('function');
+    });
+
+    it('should add appender to all loggers', () => {
+      const disposable = LoggerFactory.applyAppender(mockAppender);
+
+      const logger = LoggerFactory.getLogger('test');
+      logger.info('test message');
+
+      expect(mockAppender.log).toHaveBeenCalled();
+
+      // Clean up
+      disposable.dispose();
+    });
+
+    it('should remove appender when disposed', () => {
+      const disposable = LoggerFactory.applyAppender(mockAppender);
+
+      const logger = LoggerFactory.getLogger('test');
+      logger.info('test message');
+
+      expect(mockAppender.log).toHaveBeenCalledTimes(1);
+
+      // Dispose and try again
+      disposable.dispose();
+      logger.info('test message 2');
+
+      // Should still be called once since we disposed the mock appender
+      // but the default appenders are still there
+      expect(mockAppender.log).toHaveBeenCalledTimes(1);
+    });
+  });
+});

tests/LoggingLevelMapping.test.ts

@@ -0,0 +1,94 @@
+import { describe, it, expect } from 'bun:test';
+import LoggingLevelMapping from '../src/level/LoggingLevelMapping';
+import { LoggingLevel, LoggingLevelType } from '../src/level/LoggingLevel';
+
+describe('LoggingLevelMapping', () => {
+  describe('convertLoggingLevelToLoggingLevelType', () => {
+    it('should convert LoggingLevel.Off to "Off"', () => {
+      expect(LoggingLevelMapping.convertLoggingLevelToLoggingLevelType(LoggingLevel.Off)).toBe('Off');
+    });
+
+    it('should convert LoggingLevel.Debug to "Debug"', () => {
+      expect(LoggingLevelMapping.convertLoggingLevelToLoggingLevelType(LoggingLevel.Debug)).toBe('Debug');
+    });
+
+    it('should convert LoggingLevel.Trace to "Trace"', () => {
+      expect(LoggingLevelMapping.convertLoggingLevelToLoggingLevelType(LoggingLevel.Trace)).toBe('Trace');
+    });
+
+    it('should convert LoggingLevel.Info to "Info"', () => {
+      expect(LoggingLevelMapping.convertLoggingLevelToLoggingLevelType(LoggingLevel.Info)).toBe('Info');
+    });
+
+    it('should convert LoggingLevel.Silly to "Silly"', () => {
+      expect(LoggingLevelMapping.convertLoggingLevelToLoggingLevelType(LoggingLevel.Silly)).toBe('Silly');
+    });
+
+    it('should convert LoggingLevel.Warn to "Warn"', () => {
+      expect(LoggingLevelMapping.convertLoggingLevelToLoggingLevelType(LoggingLevel.Warn)).toBe('Warn');
+    });
+
+    it('should convert LoggingLevel.Error to "Error"', () => {
+      expect(LoggingLevelMapping.convertLoggingLevelToLoggingLevelType(LoggingLevel.Error)).toBe('Error');
+    });
+
+    it('should convert LoggingLevel.All to "All"', () => {
+      expect(LoggingLevelMapping.convertLoggingLevelToLoggingLevelType(LoggingLevel.All)).toBe('All');
+    });
+  });
+
+  describe('convertLoggingLevelTypeToLoggingLevel', () => {
+    it('should convert "Off" to LoggingLevel.Off', () => {
+      expect(LoggingLevelMapping.convertLoggingLevelTypeToLoggingLevel('Off')).toBe(LoggingLevel.Off);
+    });
+
+    it('should convert "Debug" to LoggingLevel.Debug', () => {
+      expect(LoggingLevelMapping.convertLoggingLevelTypeToLoggingLevel('Debug')).toBe(LoggingLevel.Debug);
+    });
+
+    it('should convert "Trace" to LoggingLevel.Trace', () => {
+      expect(LoggingLevelMapping.convertLoggingLevelTypeToLoggingLevel('Trace')).toBe(LoggingLevel.Trace);
+    });
+
+    it('should convert "Info" to LoggingLevel.Info', () => {
+      expect(LoggingLevelMapping.convertLoggingLevelTypeToLoggingLevel('Info')).toBe(LoggingLevel.Info);
+    });
+
+    it('should convert "Silly" to LoggingLevel.Silly', () => {
+      expect(LoggingLevelMapping.convertLoggingLevelTypeToLoggingLevel('Silly')).toBe(LoggingLevel.Silly);
+    });
+
+    it('should convert "Warn" to LoggingLevel.Warn', () => {
+      expect(LoggingLevelMapping.convertLoggingLevelTypeToLoggingLevel('Warn')).toBe(LoggingLevel.Warn);
+    });
+
+    it('should convert "Error" to LoggingLevel.Error', () => {
+      expect(LoggingLevelMapping.convertLoggingLevelTypeToLoggingLevel('Error')).toBe(LoggingLevel.Error);
+    });
+
+    it('should convert "All" to LoggingLevel.All', () => {
+      expect(LoggingLevelMapping.convertLoggingLevelTypeToLoggingLevel('All')).toBe(LoggingLevel.All);
+    });
+  });
+
+  describe('round trip conversion', () => {
+    it('should maintain consistency in round trip conversions', () => {
+      const allLevels: LoggingLevel[] = [
+        LoggingLevel.Off,
+        LoggingLevel.Debug,
+        LoggingLevel.Trace,
+        LoggingLevel.Info,
+        LoggingLevel.Silly,
+        LoggingLevel.Warn,
+        LoggingLevel.Error,
+        LoggingLevel.All
+      ];
+
+      for (const level of allLevels) {
+        const type = LoggingLevelMapping.convertLoggingLevelToLoggingLevelType(level);
+        const backToLevel = LoggingLevelMapping.convertLoggingLevelTypeToLoggingLevel(type);
+        expect(backToLevel).toBe(level);
+      }
+    });
+  });
+});

tests/TechnikerMeAppender.test.ts

@@ -0,0 +1,134 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from 'bun:test';
+import TechnikerMeAppender from '../src/appenders/TechnikerMeAppender';
+
+describe('TechnikerMeAppender', () => {
+  let technikerMeAppender: TechnikerMeAppender;
+  let mockFetch: any;
+  let originalFetch: any;
+
+  beforeEach(() => {
+    technikerMeAppender = new TechnikerMeAppender();
+
+    // Mock fetch
+    originalFetch = global.fetch;
+    mockFetch = vi.fn();
+    global.fetch = mockFetch;
+  });
+
+  afterEach(() => {
+    global.fetch = originalFetch;
+    vi.clearAllMocks();
+  });
+
+  describe('log method', () => {
+    it('should queue messages and attempt to post them', () => {
+      mockFetch.mockResolvedValue(new Response());
+
+      technikerMeAppender.log('2023-01-01T00:00:00.000Z', 'Info', 'test-category', 'test message');
+
+      // Should attempt to fetch
+      expect(mockFetch).toHaveBeenCalledWith(
+        'https://logserver.techniker.me/api/logs',
+        expect.objectContaining({
+          method: 'POST',
+          headers: {
+            'Content-Type': 'application/json',
+            Accept: 'application/json'
+          },
+          mode: 'no-cors'
+        })
+      );
+
+      const callArgs = mockFetch.mock.calls[0];
+      const body = JSON.parse(callArgs[1].body);
+
+      expect(body).toEqual({
+        timestamp: '2023-01-01T00:00:00.000Z',
+        level: 'Info',
+        category: 'test-category',
+        message: 'test message',
+        domain: '' // Empty since we're in Node.js environment
+      });
+    });
+
+    it('should include domain in browser environment', () => {
+      // Mock window.location
+      const originalWindow = global.window;
+      global.window = {
+        location: {
+          hostname: 'example.com'
+        }
+      } as any;
+
+      const appender = new TechnikerMeAppender();
+      mockFetch.mockResolvedValue(new Response());
+
+      appender.log('2023-01-01T00:00:00.000Z', 'Info', 'test-category', 'test message');
+
+      const callArgs = mockFetch.mock.calls[0];
+      const body = JSON.parse(callArgs[1].body);
+
+      expect(body.domain).toBe('example.com');
+
+      // Restore
+      global.window = originalWindow;
+    });
+
+    it('should handle missing window gracefully', () => {
+      const originalWindow = global.window;
+      delete (global as any).window;
+
+      const appender = new TechnikerMeAppender();
+      mockFetch.mockResolvedValue(new Response());
+
+      appender.log('2023-01-01T00:00:00.000Z', 'Info', 'test-category', 'test message');
+
+      const callArgs = mockFetch.mock.calls[0];
+      const body = JSON.parse(callArgs[1].body);
+
+      expect(body.domain).toBe('');
+
+      // Restore
+      global.window = originalWindow;
+    });
+  });
+
+  describe('error handling', () => {
+    it('should handle missing fetch API', () => {
+      const originalFetch = global.fetch;
+      delete (global as any).fetch;
+
+      const consoleSpy = vi.spyOn(console, 'error').mockImplementation(() => {});
+
+      technikerMeAppender.log('2023-01-01T00:00:00.000Z', 'Info', 'test-category', 'test message');
+
+      expect(consoleSpy).toHaveBeenCalledWith('Fetch API is not available in this environment');
+
+      consoleSpy.mockRestore();
+      global.fetch = originalFetch;
+    });
+  });
+
+  describe('message queuing', () => {
+    it('should attempt to send messages', () => {
+      mockFetch.mockResolvedValue(new Response());
+
+      technikerMeAppender.log('2023-01-01T00:00:00.000Z', 'Info', 'cat1', 'msg1');
+
+      expect(mockFetch).toHaveBeenCalledTimes(1);
+      expect(mockFetch).toHaveBeenCalledWith(
+        'https://logserver.techniker.me/api/logs',
+        expect.objectContaining({
+          method: 'POST',
+          headers: {
+            'Content-Type': 'application/json',
+            Accept: 'application/json'
+          },
+          mode: 'no-cors'
+        })
+      );
+    });
+
+    // Note: Complex async queuing behavior is tested by the core functionality test above
+  });
+});

tests/Threshold.test.ts

@@ -0,0 +1,66 @@
+import { describe, it, expect } from 'bun:test';
+import Threshold from '../src/level/Threshold';
+import { LoggingLevel } from '../src/level/LoggingLevel';
+import Defaults from '../src/Defaults';
+
+describe('Threshold', () => {
+  describe('constructor', () => {
+    it('should use provided logging level', () => {
+      const threshold = new Threshold(LoggingLevel.Debug);
+
+      expect(threshold.value).toBe(LoggingLevel.Debug);
+    });
+
+    it('should use default logging level when none provided', () => {
+      const threshold = new Threshold();
+
+      expect(threshold.value).toBe(Defaults.loggingLevel);
+    });
+  });
+
+  describe('value getter/setter', () => {
+    it('should get and set threshold value', () => {
+      const threshold = new Threshold(LoggingLevel.Info);
+
+      expect(threshold.value).toBe(LoggingLevel.Info);
+
+      threshold.value = LoggingLevel.Debug;
+      expect(threshold.value).toBe(LoggingLevel.Debug);
+
+      threshold.value = LoggingLevel.Error;
+      expect(threshold.value).toBe(LoggingLevel.Error);
+    });
+  });
+
+  describe('threshold comparison logic', () => {
+    it('should work correctly for different levels', () => {
+      const threshold = new Threshold(LoggingLevel.Info);
+
+      // Info level (30) should allow Info (30), Warn (50), Error (60) but not Debug (10)
+      expect(threshold.value > LoggingLevel.Info).toBe(false); // 30 > 30 = false, so Info logs
+      expect(threshold.value > LoggingLevel.Warn).toBe(false); // 30 > 50 = false, so Warn logs
+      expect(threshold.value > LoggingLevel.Error).toBe(false); // 30 > 60 = false, so Error logs
+      expect(threshold.value > LoggingLevel.Debug).toBe(true); // 30 > 10 = true, so Debug doesn't log
+    });
+
+    it('should work with Debug threshold', () => {
+      const threshold = new Threshold(LoggingLevel.Debug);
+
+      // Debug level (10) should allow all levels
+      expect(threshold.value > LoggingLevel.Debug).toBe(false); // 10 > 10 = false
+      expect(threshold.value > LoggingLevel.Info).toBe(false); // 10 > 30 = false
+      expect(threshold.value > LoggingLevel.Warn).toBe(false); // 10 > 50 = false
+      expect(threshold.value > LoggingLevel.Error).toBe(false); // 10 > 60 = false
+    });
+
+    it('should work with Error threshold', () => {
+      const threshold = new Threshold(LoggingLevel.Error);
+
+      // Error level (60) should only allow Error and above
+      expect(threshold.value > LoggingLevel.Error).toBe(false); // 60 > 60 = false, so Error logs
+      expect(threshold.value > LoggingLevel.Warn).toBe(true); // 60 > 50 = true, so Warn doesn't log
+      expect(threshold.value > LoggingLevel.Info).toBe(true); // 60 > 30 = true, so Info doesn't log
+      expect(threshold.value > LoggingLevel.Debug).toBe(true); // 60 > 10 = true, so Debug doesn't log
+    });
+  });
+});