import { readFileSync, existsSync, watch, type FSWatcher } from "fs";
import { homedir } from "os";
import { join } from "path";
import type { GatewayConfig } from "./types.js";
const DEFAULT_CONFIG_PATH = join(homedir(), ".config", "mcp-gateway", "config.json");
export class Config {
private config: GatewayConfig;
private configPath: string;
private watcher?: FSWatcher;
constructor(path?: string) {
this.configPath = path || process.env.MCP_GATEWAY_CONFIG || DEFAULT_CONFIG_PATH;
this.config = this.load();
}
get<K extends keyof GatewayConfig>(key: K): GatewayConfig[K] | undefined {
return this.config[key];
}
getAll(): GatewayConfig {
return { ...this.config };
}
set(key: string, value: any): void {
this.config[key] = value;
}
getPath(): string {
return this.configPath;
}
reload(): GatewayConfig {
this.config = this.load();
return this.config;
}
watch(callback: (config: GatewayConfig) => void): void {
if (this.watcher) return;
this.watcher = watch(this.configPath, (event: string) => {
if (event !== "change") return;
this.reload();
callback(this.config);
});
console.error(` Watching config: ${this.configPath}`);
}
stopWatching(): void {
this.watcher?.close();
this.watcher = undefined;
}
private load(): GatewayConfig {
if (!existsSync(this.configPath)) return {};
return JSON.parse(readFileSync(this.configPath, "utf-8"));
}
}
export function getDefaultConfigPath(): string {
return process.env.MCP_GATEWAY_CONFIG || DEFAULT_CONFIG_PATH;
}
