feat: implement dynamic database connection reloading

src/db/index.ts

@@ -1,43 +1,77 @@
-import { drizzle as nodeDrizzle } from "drizzle-orm/node-postgres";
+import { drizzle, NodePgDatabase } from "drizzle-orm/node-postgres";
 import { Pool } from "pg";
 import * as schema from "./schema";
 import fs from "fs";
 import path from "path";
 
-let connectionString = process.env.DATABASE_URL;
+let pool: Pool | null = null;
+let currentDb: NodePgDatabase<typeof schema> | null = null;
 
 function maskUrl(url: string | undefined) {
     if (!url) return "undefined";
     return url.replace(/:([^@]+)@/, ":****@");
 }
 
-console.log("[DB] Initial DATABASE_URL (env):", maskUrl(connectionString));
+/**
+ * Initializes or returns the current database instance.
+ */
+export function getDb() {
+    if (currentDb) return currentDb;
 
-// On tente de lire la config sauvegardée via l'UI
-try {
-    const CONFIG_PATH = path.join(process.cwd(), "data", ".db-config.json");
-    if (fs.existsSync(CONFIG_PATH)) {
-        console.log("[DB] Found config file at:", CONFIG_PATH);
-        const config = JSON.parse(fs.readFileSync(CONFIG_PATH, "utf-8"));
-        if (config.url) {
-            connectionString = config.url;
-            console.log("[DB] Using saved database URL:", maskUrl(connectionString));
+    let connectionString = process.env.DATABASE_URL;
+
+    console.log("[DB] Initializing connection...");
+    console.log("[DB] Env DATABASE_URL:", maskUrl(process.env.DATABASE_URL));
+
+    try {
+        const CONFIG_PATH = path.join(process.cwd(), "data", ".db-config.json");
+        if (fs.existsSync(CONFIG_PATH)) {
+            console.log("[DB] Found config file at:", CONFIG_PATH);
+            const config = JSON.parse(fs.readFileSync(CONFIG_PATH, "utf-8"));
+            if (config.url) {
+                connectionString = config.url;
+                console.log("[DB] Using saved database URL:", maskUrl(connectionString));
+            }
         } else {
-            console.warn("[DB] Config file found but no 'url' key present.");
+            console.log("[DB] No saved config file found. Using environment variable.");
         }
-    } else {
-        console.log("[DB] No saved config file found at:", CONFIG_PATH, "(Falling back to env)");
+    } catch (err) {
+        console.error("[DB] Error reading config file:", err);
     }
-} catch (err) {
-    console.error("[DB] Error reading database config file:", err);
+
+    if (!connectionString) {
+        console.error("[DB] CRITICAL: No database connection string available!");
+    }
+
+    pool = new Pool({
+        connectionString,
+    });
+
+    currentDb = drizzle(pool, { schema });
+    return currentDb;
 }
 
-if (!connectionString) {
-    console.error("[DB] CRITICAL: No database connection string available!");
+/**
+ * Resets the current database connection. 
+ * Called when settings are updated via the UI.
+ */
+export function refreshDb() {
+    console.log("[DB] Refreshing database connection...");
+    if (pool) {
+        pool.end().catch(err => console.error("[DB] Error closing pool:", err));
+        pool = null;
+    }
+    currentDb = null;
 }
 
-const pool = new Pool({
-    connectionString,
+/**
+ * Proxy for the 'db' instance. 
+ * Allows existing imports (import { db } from "@/db") to work 
+ * while the underlying instance can be hot-swapped.
+ */
+export const db = new Proxy({} as NodePgDatabase<typeof schema>, {
+    get(target, prop, receiver) {
+        const d = getDb();
+        return Reflect.get(d, prop, receiver);
+    }
 });
-
-export const db = nodeDrizzle(pool, { schema });

src/features/settings/actions.ts

@@ -41,6 +41,11 @@ export async function saveDatabaseSettings(url: string) {
 
         await fs.writeFile(CONFIG_FILE, JSON.stringify(config, null, 2));
         console.log("Database configuration saved to:", CONFIG_FILE);
+
+        // Refresh the shared DB instance immediately
+        const { refreshDb } = await import("@/db");
+        refreshDb();
+
         return { success: true };
     } catch (error: unknown) {
         const errorMessage = error instanceof Error ? error.message : String(error);