/**
* JSON file-based storage implementation
*/
import { promises as fs } from 'fs';
import { existsSync } from 'fs';
import type { Store, AgentCard } from '../types/index.js';
import { AgentAlreadyExistsError, AgentNotFoundError } from '../types/index.js';
export class JsonFileStore implements Store {
private filePath: string;
private agents: Map<string, AgentCard>;
private initialized: boolean = false;
constructor(filePath: string) {
this.filePath = filePath;
this.agents = new Map();
}
/**
* Initialize the store by loading data from file
*/
private async initialize(): Promise<void> {
if (this.initialized) {
return;
}
if (existsSync(this.filePath)) {
try {
const data = await fs.readFile(this.filePath, 'utf-8');
const parsed = JSON.parse(data);
if (typeof parsed === 'object' && parsed !== null) {
Object.entries(parsed).forEach(([name, agentCard]) => {
this.agents.set(name, agentCard as AgentCard);
});
}
} catch (error) {
console.error(`Warning: Could not read ${this.filePath}, starting with empty registry`);
}
}
this.initialized = true;
}
/**
* Persist current state to disk
*/
private async persist(): Promise<void> {
const data: Record<string, AgentCard> = {};
this.agents.forEach((agentCard, name) => {
data[name] = agentCard;
});
await fs.writeFile(this.filePath, JSON.stringify(data, null, 2), 'utf-8');
}
async listAgents(): Promise<AgentCard[]> {
await this.initialize();
return Array.from(this.agents.values());
}
async getAgent(name: string): Promise<AgentCard | null> {
await this.initialize();
return this.agents.get(name) ?? null;
}
async createAgent(agentCard: AgentCard): Promise<AgentCard> {
await this.initialize();
if (this.agents.has(agentCard.name)) {
throw new AgentAlreadyExistsError(agentCard.name);
}
this.agents.set(agentCard.name, agentCard);
await this.persist();
return agentCard;
}
async updateAgent(name: string, agentCard: AgentCard): Promise<AgentCard | null> {
await this.initialize();
if (!this.agents.has(name)) {
return null;
}
this.agents.set(name, agentCard);
await this.persist();
return agentCard;
}
async deleteAgent(name: string): Promise<boolean> {
await this.initialize();
if (!this.agents.has(name)) {
return false;
}
this.agents.delete(name);
await this.persist();
return true;
}
}
