Firewalla MCP Server

/** * @fileoverview Environment variable utilities for configuration parsing * * Provides type-safe utilities for parsing and validating environment variables * with appropriate error handling and default values. */ import { logger } from '../monitoring/logger.js'; /** * Gets a required environment variable or throws an error if not found * * @param name - The environment variable name * @returns The environment variable value * @throws {Error} If the environment variable is not set or empty */ export function getRequiredEnvVar(name: string): string { const value = process.env[name]; if (!value) { throw new Error(`Required environment variable ${name} is not set`); } return value; } /** * Gets an optional environment variable with a fallback default value * * @param name - The environment variable name * @param defaultValue - The default value to use if not set * @returns The environment variable value or default */ export function getOptionalEnvVar(name: string, defaultValue: string): string { return process.env[name] || defaultValue; } /** * Safely parses an environment variable to an integer with validation * * @param name - The environment variable name to parse * @param defaultValue - The default value to use if parsing fails * @param min - Optional minimum value for validation * @param max - Optional maximum value for validation * @returns The parsed integer value or the default value * @throws {Error} If the parsed value is outside the valid range */ export function getOptionalEnvInt( name: string, defaultValue: number, min?: number, max?: number ): number { const envValue = process.env[name]; if (envValue === undefined || envValue === '') { return defaultValue; } const parsed = parseInt(envValue, 10); if (!Number.isFinite(parsed)) { logger.warn(`Invalid numeric value for environment variable`, { environment_variable: name, invalid_value: envValue, default_value: defaultValue, action: 'using_default', }); return defaultValue; } if (min !== undefined && parsed < min) { throw new Error( `Environment variable ${name} must be at least ${min}, got: ${parsed}` ); } if (max !== undefined && parsed > max) { throw new Error( `Environment variable ${name} must be at most ${max}, got: ${parsed}` ); } return parsed; } /** * Safely parses an environment variable to a boolean with validation * * @param name - The environment variable name to parse * @param defaultValue - The default value to use if parsing fails * @returns The parsed boolean value or default */ export function getOptionalEnvBoolean( name: string, defaultValue: boolean ): boolean { const envValue = process.env[name]; if (envValue === undefined || envValue === '') { return defaultValue; } const normalized = envValue.toLowerCase().trim(); if (['true', '1', 'yes', 'on'].includes(normalized)) { return true; } if (['false', '0', 'no', 'off'].includes(normalized)) { return false; } logger.warn(`Invalid boolean value for environment variable`, { environment_variable: name, invalid_value: envValue, default_value: defaultValue, action: 'using_default', }); return defaultValue; }