google-auth-service.ts•2.53 kB
import { google } from "googleapis";
import { OAuth2Client } from "google-auth-library";
interface GoogleCredentials {
web?: {
client_id: string;
client_secret: string;
redirect_uris: string[];
};
installed?: {
client_id: string;
client_secret: string;
redirect_uris: string[];
};
}
export class GoogleAuthService {
private static instance: GoogleAuthService;
private oAuth2Client: OAuth2Client | null = null;
private constructor() {}
static getInstance(): GoogleAuthService {
if (!GoogleAuthService.instance) {
GoogleAuthService.instance = new GoogleAuthService();
}
return GoogleAuthService.instance;
}
async initialize(): Promise<void> {
try {
const credentialsBase64 = process.env.GOOGLE_CREDENTIALS;
if (!credentialsBase64) {
throw new Error("GOOGLE_CREDENTIALS environment variable is not set");
}
const decodedCredentials = Buffer.from(credentialsBase64, "base64").toString();
const credentials: GoogleCredentials = JSON.parse(decodedCredentials);
// Check credentials format first
if (!credentials.web && !credentials.installed) {
throw new Error(
`Invalid credentials format: credentials must contain either 'web' or 'installed' configuration. Received keys: ${Object.keys(credentials).join(", ")}`,
);
}
const config = credentials.web || credentials.installed;
if (!config) {
throw new Error("Neither web nor installed credentials found");
}
const { client_secret, client_id, redirect_uris } = config;
if (!client_secret || !client_id || !redirect_uris?.length) {
throw new Error(
"Invalid credentials: missing required fields (client_secret, client_id, or redirect_uris)",
);
}
this.oAuth2Client = new google.auth.OAuth2(client_id, client_secret, redirect_uris[0]);
const tokenBase64 = process.env.GOOGLE_TOKEN;
try {
if (tokenBase64) {
const token = JSON.parse(Buffer.from(tokenBase64, "base64").toString());
this.oAuth2Client.setCredentials(token);
}
} catch (error) {
console.error("Error parsing token:", error);
throw error;
}
} catch (error) {
console.error("Error loading Google credentials:", error);
throw error;
}
}
getAuth(): OAuth2Client {
if (!this.oAuth2Client) {
throw new Error("OAuth2Client not initialized");
}
return this.oAuth2Client;
}
}