import winston from 'winston';
describe('Logger Configuration', () => {
let originalEnv: NodeJS.ProcessEnv;
beforeEach(() => {
originalEnv = { ...process.env };
// Clear any winston instances
jest.resetModules();
});
afterEach(() => {
process.env = originalEnv;
});
it('should use file transport by default', () => {
delete process.env.LOG_OUTPUT;
const { logger } = require('../logger');
expect(logger.transports).toHaveLength(1);
expect(logger.transports[0]).toBeInstanceOf(winston.transports.File);
expect((logger.transports[0] as winston.transports.FileTransportInstance).filename).toBe(
'dynatrace-managed-mcp.log',
);
});
it('should use custom file path when LOG_FILE is set', () => {
process.env.LOG_OUTPUT = 'file';
process.env.LOG_FILE = 'custom-log-path.log';
jest.resetModules();
const { logger } = require('../logger');
expect(logger.transports).toHaveLength(1);
expect(logger.transports[0]).toBeInstanceOf(winston.transports.File);
expect((logger.transports[0] as winston.transports.FileTransportInstance).filename).toBe('custom-log-path.log');
});
it('should use stderr transport for errors/warnings only', () => {
process.env.LOG_OUTPUT = 'stderr';
jest.resetModules();
const { logger } = require('../logger');
expect(logger.transports).toHaveLength(1);
expect(logger.transports[0]).toBeInstanceOf(winston.transports.Console);
const stderrLevels = (logger.transports[0] as winston.transports.ConsoleTransportInstance).stderrLevels;
expect(stderrLevels).toBeDefined();
expect(stderrLevels).toHaveProperty('error');
expect(stderrLevels).toHaveProperty('warn');
});
it('should use stderr-all transport for all log levels', () => {
process.env.LOG_OUTPUT = 'stderr-all';
jest.resetModules();
const { logger } = require('../logger');
expect(logger.transports).toHaveLength(1);
expect(logger.transports[0]).toBeInstanceOf(winston.transports.Console);
const stderrLevels = (logger.transports[0] as winston.transports.ConsoleTransportInstance).stderrLevels;
expect(stderrLevels).toBeDefined();
expect(stderrLevels).toHaveProperty('info');
expect(stderrLevels).toHaveProperty('debug');
});
it('should use stdout transport when LOG_OUTPUT is console', () => {
process.env.LOG_OUTPUT = 'console';
jest.resetModules();
const { logger } = require('../logger');
expect(logger.transports).toHaveLength(1);
expect(logger.transports[0]).toBeInstanceOf(winston.transports.Console);
const transport = logger.transports[0] as winston.transports.ConsoleTransportInstance;
const stderrLevels = transport.stderrLevels;
if (stderrLevels) {
expect(Object.keys(stderrLevels)).toHaveLength(0);
}
});
it('should use stdout transport when LOG_OUTPUT is stdout', () => {
process.env.LOG_OUTPUT = 'stdout';
jest.resetModules();
const { logger } = require('../logger');
expect(logger.transports).toHaveLength(1);
expect(logger.transports[0]).toBeInstanceOf(winston.transports.Console);
});
it('should use both file and stdout when LOG_OUTPUT is file+console', () => {
process.env.LOG_OUTPUT = 'file+console';
process.env.LOG_FILE = 'test.log';
jest.resetModules();
const { logger } = require('../logger');
expect(logger.transports).toHaveLength(2);
expect(logger.transports[0]).toBeInstanceOf(winston.transports.File);
expect(logger.transports[1]).toBeInstanceOf(winston.transports.Console);
expect((logger.transports[0] as winston.transports.FileTransportInstance).filename).toBe('test.log');
});
it('should use both file and stdout when LOG_OUTPUT is file+stdout', () => {
process.env.LOG_OUTPUT = 'file+stdout';
jest.resetModules();
const { logger } = require('../logger');
expect(logger.transports).toHaveLength(2);
expect(logger.transports[0]).toBeInstanceOf(winston.transports.File);
expect(logger.transports[1]).toBeInstanceOf(winston.transports.Console);
});
it('should use both file and stderr when LOG_OUTPUT is file+stderr', () => {
process.env.LOG_OUTPUT = 'file+stderr';
process.env.LOG_FILE = 'combined.log';
jest.resetModules();
const { logger } = require('../logger');
expect(logger.transports).toHaveLength(2);
expect(logger.transports[0]).toBeInstanceOf(winston.transports.File);
expect(logger.transports[1]).toBeInstanceOf(winston.transports.Console);
expect((logger.transports[0] as winston.transports.FileTransportInstance).filename).toBe('combined.log');
const stderrLevels = (logger.transports[1] as winston.transports.ConsoleTransportInstance).stderrLevels;
expect(stderrLevels).toBeDefined();
expect(stderrLevels).toHaveProperty('error');
expect(stderrLevels).toHaveProperty('warn');
});
it('should have no transports when LOG_OUTPUT is disabled', () => {
process.env.LOG_OUTPUT = 'disabled';
jest.resetModules();
const { logger } = require('../logger');
expect(logger.transports).toHaveLength(0);
});
it('should default to info log level', () => {
delete process.env.LOG_LEVEL;
jest.resetModules();
const { logger } = require('../logger');
expect(logger.level).toBe('info');
});
it('should respect custom log level', () => {
process.env.LOG_LEVEL = 'debug';
jest.resetModules();
const { logger } = require('../logger');
expect(logger.level).toBe('debug');
});
it('should handle case-insensitive LOG_OUTPUT values', () => {
process.env.LOG_OUTPUT = 'CONSOLE';
jest.resetModules();
const { logger } = require('../logger');
expect(logger.transports).toHaveLength(1);
expect(logger.transports[0]).toBeInstanceOf(winston.transports.Console);
});
});
