Refactor code structure for improved readability and maintainability

api/Dockerfile

@@ -1,9 +1,9 @@
-FROM node:20-alpine
+FROM node:22-alpine
 
 WORKDIR /app
 
 COPY package*.json ./
-RUN npm install
+RUN npm ci
 
 COPY src ./src
 

api/package.json

@@ -5,7 +5,8 @@
   "type": "module",
   "scripts": {
     "dev": "node --watch src/index.js",
-    "start": "node src/index.js"
+    "start": "node src/index.js",
+    "check": "node --check src/index.js && node --check src/db.js"
   },
   "dependencies": {
     "bcryptjs": "^2.4.3",
@@ -16,4 +17,4 @@
     "jsonwebtoken": "^9.0.2",
     "mysql2": "^3.12.0"
   }
-}
+}

api/src/db.js

@@ -1,4 +1,4 @@
-import mysql from "mysql2/promise";
+import mysql from "mysql2/promise";
 import { config } from "./config.js";
 
 function createPool(password) {
@@ -24,7 +24,15 @@ function isAccessDenied(error) {
   return error?.code === "ER_ACCESS_DENIED_ERROR";
 }
 
-async function query(sql, values) {
+function isTransientConnectionError(error) {
+  return ["ECONNREFUSED", "ECONNRESET", "ETIMEDOUT", "PROTOCOL_CONNECTION_LOST"].includes(error?.code);
+}
+
+function delay(milliseconds) {
+  return new Promise((resolve) => setTimeout(resolve, milliseconds));
+}
+
+async function queryWithCredentials(sql, values) {
   try {
     return await activePool.query(sql, values);
   } catch (error) {
@@ -33,21 +41,18 @@ async function query(sql, values) {
     }
 
     for (const password of candidatePasswords) {
-      if (password === activePassword) {
-        continue;
-      }
-
+      if (password === activePassword) continue;
       const fallbackPool = createPool(password);
       try {
         const result = await fallbackPool.query(sql, values);
+        const previousPool = activePool;
         activePool = fallbackPool;
         activePassword = password;
+        previousPool.end().catch(() => undefined);
         return result;
       } catch (fallbackError) {
         await fallbackPool.end().catch(() => undefined);
-        if (!isAccessDenied(fallbackError)) {
-          throw fallbackError;
-        }
+        if (!isAccessDenied(fallbackError)) throw fallbackError;
       }
     }
 
@@ -55,4 +60,18 @@ async function query(sql, values) {
   }
 }
 
-export const pool = { query };
+async function query(sql, values) {
+  let lastError;
+  for (let attempt = 0; attempt < 5; attempt += 1) {
+    try {
+      return await queryWithCredentials(sql, values);
+    } catch (error) {
+      lastError = error;
+      if (!isTransientConnectionError(error) || attempt === 4) throw error;
+      await delay(250 * 2 ** attempt);
+    }
+  }
+  throw lastError;
+}
+
+export const pool = { query };

api/src/index.js

@@ -202,18 +202,33 @@ async function ensureRolesSchema() {
 }
 
 
-function sanitizeApiSettings(body = {}) {
+function updateSecret(body, existing, field, clearField) {
+  if (body[clearField] === true) return "";
+  const replacement = String(body[field] ?? "").trim();
+  return replacement || String(existing[field] || "").trim();
+}
+
+function sanitizeApiSettings(body = {}, existing = {}) {
   return {
-    mailUrl: String(body.mailUrl || "https://mailapi.se-inno.de").trim() || "https://mailapi.se-inno.de",
-    mailApiKey: String(body.mailApiKey || "").trim(),
-    whatsappUrl: String(body.whatsappUrl || "https://whatsappapi.se-inno.de").trim() || "https://whatsappapi.se-inno.de",
-    whatsappApiKey: String(body.whatsappApiKey || "").trim(),
-    voipUrl: String(body.voipUrl || "https://voipapi.se-inno.de").trim() || "https://voipapi.se-inno.de",
-    voipApiKey: String(body.voipApiKey || "").trim(),
+    mailUrl: String(body.mailUrl ?? existing.mailUrl ?? "https://mailapi.se-inno.de").trim() || "https://mailapi.se-inno.de",
+    mailApiKey: updateSecret(body, existing, "mailApiKey", "clearMailApiKey"),
+    whatsappUrl: String(body.whatsappUrl ?? existing.whatsappUrl ?? "https://whatsappapi.se-inno.de").trim() || "https://whatsappapi.se-inno.de",
+    whatsappApiKey: updateSecret(body, existing, "whatsappApiKey", "clearWhatsappApiKey"),
+    voipUrl: String(body.voipUrl ?? existing.voipUrl ?? "https://voipapi.se-inno.de").trim() || "https://voipapi.se-inno.de",
+    voipApiKey: updateSecret(body, existing, "voipApiKey", "clearVoipApiKey"),
     updatedAt: new Date().toISOString(),
   };
 }
 
+function publicApiSettings(settings = {}) {
+  return {
+    mailUrl: settings.mailUrl || "https://mailapi.se-inno.de",
+    whatsappUrl: settings.whatsappUrl || "https://whatsappapi.se-inno.de",
+    voipUrl: settings.voipUrl || "https://voipapi.se-inno.de",
+    updatedAt: settings.updatedAt || null,
+  };
+}
+
 function normalizeRunnerTime(value) {
   const raw = String(value ?? "").trim().replace(/\s*uhr$/i, "").replace(".", ":");
   const match = raw.match(/^(\d{1,2}):(\d{2})$/);
@@ -834,9 +849,8 @@ app.post("/api/dashboard/data", authenticateTokenOptional, wrap(async (req, res)
 
 app.get("/api/integrations", authenticateToken, requirePermission("manage_integrations"), wrap(async (_req, res) => {
   const current = JSON.parse(await redis.get("integration:api") || "{}");
-  const settings = sanitizeApiSettings(current);
   res.json({
-    settings,
+    settings: publicApiSettings(current),
     mailConfigured: Boolean(current.mailApiKey),
     whatsappConfigured: Boolean(current.whatsappApiKey),
     voipConfigured: Boolean(current.voipApiKey),
@@ -844,10 +858,11 @@ app.get("/api/integrations", authenticateToken, requirePermission("manage_integr
 }));
 
 app.put("/api/integrations", authenticateToken, requirePermission("manage_integrations"), wrap(async (req, res) => {
-  const payload = sanitizeApiSettings(req.body || {});
+  const current = JSON.parse(await redis.get("integration:api") || "{}");
+  const payload = sanitizeApiSettings(req.body || {}, current);
   await redis.set("integration:api", JSON.stringify(payload));
   res.json({
-    settings: payload,
+    settings: publicApiSettings(payload),
     mailConfigured: Boolean(payload.mailApiKey),
     whatsappConfigured: Boolean(payload.whatsappApiKey),
     voipConfigured: Boolean(payload.voipApiKey),