add mysql, mariadb, postgresql, sqlite volumes support

app/server/modules/backends/postgres/postgres-backend.ts

@@ -0,0 +1,57 @@
+import * as fs from "node:fs/promises";
+import { toMessage } from "../../../utils/errors";
+import { logger } from "../../../utils/logger";
+import { testPostgresConnection } from "../../../utils/database-dump";
+import type { VolumeBackend } from "../backend";
+import { BACKEND_STATUS, type BackendConfig } from "~/schemas/volumes";
+
+const mount = async (config: BackendConfig, volumePath: string) => {
+	if (config.backend !== "postgres") {
+		return { status: BACKEND_STATUS.error, error: "Invalid backend type" };
+	}
+
+	logger.info(`Testing PostgreSQL connection to: ${config.host}:${config.port}`);
+
+	try {
+		await testPostgresConnection(config);
+		await fs.mkdir(volumePath, { recursive: true });
+
+		logger.info("PostgreSQL connection successful");
+		return { status: BACKEND_STATUS.mounted };
+	} catch (error) {
+		logger.error("Failed to connect to PostgreSQL:", error);
+		return { status: BACKEND_STATUS.error, error: toMessage(error) };
+	}
+};
+
+const unmount = async (volumePath: string) => {
+	logger.info("Cleaning up PostgreSQL dump directory");
+	
+	try {
+		await fs.rm(volumePath, { recursive: true, force: true });
+		return { status: BACKEND_STATUS.unmounted };
+	} catch (error) {
+		logger.warn(`Failed to clean up PostgreSQL dump directory: ${toMessage(error)}`);
+		return { status: BACKEND_STATUS.unmounted };
+	}
+};
+
+const checkHealth = async (config: BackendConfig) => {
+	if (config.backend !== "postgres") {
+		return { status: BACKEND_STATUS.error, error: "Invalid backend type" };
+	}
+
+	try {
+		await testPostgresConnection(config);
+		return { status: BACKEND_STATUS.mounted };
+	} catch (error) {
+		logger.error("PostgreSQL health check failed:", error);
+		return { status: BACKEND_STATUS.error, error: toMessage(error) };
+	}
+};
+
+export const makePostgresBackend = (config: BackendConfig, volumePath: string): VolumeBackend => ({
+	mount: () => mount(config, volumePath),
+	unmount: () => unmount(volumePath),
+	checkHealth: () => checkHealth(config),
+});