feat: add ESLint and Prettier configuration for code quality

- Added ESLint with TypeScript support and custom rules.
- Introduced Prettier for consistent code formatting.
- Updated package.json to include lint and format scripts.
- Modified db.ts to ensure proper parsing of BIGINT types from PostgreSQL.
- Enhanced webRoutes to coerce timestamp fields to numbers and format isDeleted as boolean.

CollabTableAndroid/README.md

@@ -9,7 +9,7 @@ A collaborative table management Android application built with Jetpack Compose
 - Add items with values for each field
 - Beautiful Material 3 design with dynamic colors
 - Local Room database for offline support
-- Automatic synchronization with server
+- Automatic synchronization with server (WebSocket-first with HTTP fallback)
 - Soft delete support (items can be recovered on server)
 
 ## Architecture
@@ -69,7 +69,8 @@ app/src/main/java/com/collabtable/app/
 - **Jetpack Compose**: Modern declarative UI toolkit
 - **Material 3**: Latest Material Design guidelines
 - **Room**: Local SQLite database
-- **Retrofit**: REST API client
+- **Retrofit**: REST API client (fallback)
+- **OkHttp WebSocket**: Real-time sync channel
 - **Kotlin Coroutines**: Asynchronous programming
 - **Flow**: Reactive data streams
 
@@ -97,12 +98,17 @@ app/src/main/java/com/collabtable/app/
 
 ## Synchronization
 
-The app includes sync functionality that:
+The app uses a WebSocket-first sync strategy with an HTTP fallback:
-- Sends local changes to the server
-- Receives changes from other clients
-- Resolves conflicts using timestamps (latest wins)
 
-To trigger sync, you can call the `SyncRepository.performSync()` method from your code.
+- WebSocket (`/api/ws`): Sends a `sync` message with local changes and receives deltas plus the new `serverTimestamp`.
+- HTTP (`POST /api/sync`): Used automatically as a fallback if the WS exchange fails.
+
+Behavior:
+- Sends local changes since the last sync and receives server changes since the last known timestamp.
+- Timestamps are used to resolve conflicts (latest wins).
+- If the server is protected with `SERVER_PASSWORD`, the app sends `Authorization: Bearer <password>` for both HTTP and WebSocket.
+
+To trigger sync programmatically, call `SyncRepository.performSync()`.
 
 ## Building for Release
 

CollabTableAndroid/app/build.gradle

@@ -2,6 +2,8 @@ plugins {
     id 'com.android.application'
     id 'org.jetbrains.kotlin.android'
     id 'com.google.devtools.ksp'
+    id 'org.jlleitschuh.gradle.ktlint'
+    id 'io.gitlab.arturbosch.detekt'
 }
 
 android {
@@ -87,3 +89,16 @@ dependencies {
     debugImplementation 'androidx.compose.ui:ui-tooling'
     debugImplementation 'androidx.compose.ui:ui-test-manifest'
 }
+
+// Ktlint configuration
+ktlint {
+    android.set(true)
+    ignoreFailures.set(false)
+    outputToConsole.set(true)
+}
+
+// Detekt configuration (uses default rules; customize via detekt.yml if needed)
+detekt {
+    buildUponDefaultConfig = true
+    allRules = false
+}

CollabTableAndroid/app/src/main/java/com/collabtable/app/data/api/WebSocketSyncClient.kt

@@ -36,6 +36,7 @@ object WebSocketSyncClient {
         .connectTimeout(15, TimeUnit.SECONDS)
         .readTimeout(30, TimeUnit.SECONDS)
         .writeTimeout(30, TimeUnit.SECONDS)
+        .pingInterval(15, TimeUnit.SECONDS)
         .build()
 
     private fun buildWebSocketUrl(httpApiBaseUrl: String): String {
@@ -127,8 +128,8 @@ object WebSocketSyncClient {
 
         try {
             socket = client.newWebSocket(httpRequest, listener)
-            // Wait up to 15s for response
+            // Wait up to 30s for response (WS roundtrip)
-            val result = withTimeout(15_000) { deferred.await() }
+            val result = withTimeout(30_000) { deferred.await() }
             return@withContext result
         } catch (e: Exception) {
             Logger.w("WS", "Falling back to HTTP sync: ${e.message}")

CollabTableAndroid/build.gradle

@@ -4,4 +4,6 @@ plugins {
     id 'com.android.library' version '8.3.0' apply false
     id 'org.jetbrains.kotlin.android' version '1.9.20' apply false
     id 'com.google.devtools.ksp' version '1.9.20-1.0.14' apply false
+    id 'org.jlleitschuh.gradle.ktlint' version '12.1.0' apply false
+    id 'io.gitlab.arturbosch.detekt' version '1.23.6' apply false
 }

CollabTableServer/.dockerignore

@@ -4,6 +4,10 @@ dist
 .env
 .git
 .gitignore
+.vscode
+.idea
 README.md
 docker-compose.yml
 Dockerfile
+data/
+collabtable.db

CollabTableServer/.eslintrc.cjs

@@ -0,0 +1,22 @@
+module.exports = {
+  root: true,
+  env: {
+    es2021: true,
+    node: true,
+  },
+  parser: '@typescript-eslint/parser',
+  parserOptions: {
+    ecmaVersion: 'latest',
+    sourceType: 'module',
+    project: null,
+  },
+  plugins: ['@typescript-eslint'],
+  extends: [
+    'eslint:recommended',
+    'plugin:@typescript-eslint/recommended',
+    'prettier',
+  ],
+  rules: {
+    '@typescript-eslint/no-explicit-any': 'off',
+  },
+};

CollabTableServer/.prettierrc

@@ -0,0 +1,6 @@
+{
+  "singleQuote": true,
+  "semi": true,
+  "trailingComma": "all",
+  "printWidth": 100
+}

CollabTableServer/README.md

@@ -1,12 +1,12 @@
 # CollabTable Server
 
-A collaborative list management server built with Node.js, Express, TypeScript, and SQLite.
+A collaborative table management server built with Node.js, Express, TypeScript, and a pluggable database (SQLite or PostgreSQL).
 
 ## Features
 
 - RESTful API for managing lists, fields, items, and values
-- Real-time synchronization support
+- Real-time synchronization via WebSocket (primary) with HTTP fallback
-- SQLite database with Sequelize ORM
+- SQLite (better-sqlite3) or PostgreSQL (pg) database backends
 - Dockerized deployment with persistent storage
 - TypeScript for type safety
 
@@ -35,7 +35,7 @@ A collaborative list management server built with Node.js, Express, TypeScript,
 
 The server will be available at `http://localhost:3000`
 
-**Important:** The SQLite database is stored in a Docker volume named `sqlite_data`, which persists across container restarts and rebuilds.
+**Important:** The default backend is SQLite with a Docker volume `sqlite_data` for persistence. You can also switch to PostgreSQL by setting environment variables.
 
 ## Local Development
 
@@ -49,9 +49,21 @@ The server will be available at `http://localhost:3000`
    cp .env.example .env
    ```
 
-3. Update the database path in `.env` if needed:
+3. Choose your database in `.env` (SQLite by default):
    ```
+   # Backend: sqlite | postgres (default sqlite)
+   DB_CLIENT=sqlite
+
+   # SQLite
    DB_PATH=./data/collabtable.db
+
+   # OR PostgreSQL
+   # DATABASE_URL=postgres://user:password@localhost:5432/collabtable
+   # PGHOST=localhost
+   # PGPORT=5432
+   # PGUSER=postgres
+   # PGPASSWORD=yourpassword
+   # PGDATABASE=collabtable
    ```
 
 4. Start the development server:
@@ -85,6 +97,13 @@ The server will be available at `http://localhost:3000`
 ### Sync
 - `POST /api/sync` - Synchronize data between client and server
 
+### WebSocket
+- `GET /api/ws` - WebSocket endpoint. Send JSON messages:
+   - `{"type":"ping"}` → `{"type":"pong"}`
+   - `{"type":"sync", "id":"<uuid>", "payload": { ...SyncRequest }}` → `{"type":"syncResponse", "id":"<uuid>", "payload": { ...SyncResponse }}`
+
+Authentication: If `SERVER_PASSWORD` is set, include header `Authorization: Bearer <password>` on HTTP and WebSocket requests.
+
 ### Health Check
 - `GET /health` - Check server health
 
@@ -205,27 +224,32 @@ docker-compose up -d --build
 ## Environment Variables
 
 - `PORT` - Server port (default: 3000)
-- `DB_PATH` - Path to SQLite database file (default: /data/collabtable.db)
 - `NODE_ENV` - Environment (development/production)
+- `SERVER_PASSWORD` - Optional shared password for API and WebSocket (recommended)
+- `DB_CLIENT` - `sqlite` (default) or `postgres`
+- `DB_PATH` - Path to SQLite database file (default: ./data/collabtable.db for local, /data/collabtable.db in Docker)
+- `DATABASE_URL` - PostgreSQL connection URL (optional alternative to PG* variables)
+- `PGHOST`, `PGPORT`, `PGUSER`, `PGPASSWORD`, `PGDATABASE` - PostgreSQL connection parameters
 
 ## Data Persistence
 
-The SQLite database file is stored in a Docker volume, ensuring data persists across:
+### SQLite
-- Container restarts
+The SQLite database file is stored in a Docker volume, ensuring data persists across container lifecycle events.
-- Container recreation
-- Docker Compose down/up cycles
 
-To backup your data:
+Backup:
 ```bash
 docker cp collabtable-server:/data/collabtable.db ./backup.db
 ```
 
-To restore data:
+Restore:
 ```bash
 docker cp ./backup.db collabtable-server:/data/collabtable.db
 docker-compose restart
 ```
 
+### PostgreSQL
+Use your normal PostgreSQL backup/restore procedures (e.g., `pg_dump`, `pg_restore`). If using the optional Dockerized Postgres service, the data is stored in a named volume (see `docker-compose.yml`).
+
 ## License
 
 MIT

CollabTableServer/docker-compose.yml

@@ -7,8 +7,20 @@ services:
     restart: unless-stopped
     environment:
       - PORT=3000
-      - DB_PATH=/data/collabtable.db
       - NODE_ENV=production
+      # Authentication (optional but recommended)
+      - SERVER_PASSWORD=change_me
+      # Database selection: sqlite | postgres (default sqlite)
+      - DB_CLIENT=sqlite
+      # SQLite path (used when DB_CLIENT=sqlite)
+      - DB_PATH=/data/collabtable.db
+      # PostgreSQL (used when DB_CLIENT=postgres) - choose either DATABASE_URL or the PG* vars
+      # - DATABASE_URL=postgres://user:password@postgres:5432/collabtable
+      # - PGHOST=postgres
+      # - PGPORT=5432
+      # - PGUSER=postgres
+      # - PGPASSWORD=yourpassword
+      # - PGDATABASE=collabtable
     ports:
       - "3000:3000"
     volumes:
@@ -16,8 +28,25 @@ services:
     networks:
       - collabtable-network
 
+  # Optional PostgreSQL database
+  # postgres:
+  #   image: postgres:16-alpine
+  #   container_name: collabtable-postgres
+  #   restart: unless-stopped
+  #   environment:
+  #     - POSTGRES_DB=collabtable
+  #     - POSTGRES_USER=postgres
+  #     - POSTGRES_PASSWORD=yourpassword
+  #   ports:
+  #     - "5432:5432"
+  #   volumes:
+  #     - pg_data:/var/lib/postgresql/data
+  #   networks:
+  #     - collabtable-network
+
 volumes:
   sqlite_data:
+  # pg_data:
 
 networks:
   collabtable-network:

CollabTableServer/package.json

@@ -7,6 +7,8 @@
     "start": "node dist/index.js",
     "dev": "ts-node-dev --respawn --transpile-only src/index.ts",
     "build": "tsc",
+    "lint": "eslint src --ext .ts",
+    "format": "prettier --write \"**/*.{ts,js,json,md,yml,yaml}\"",
     "test": "echo \"Error: no test specified\" && exit 1"
   },
   "keywords": ["collaboration", "api", "express"],
@@ -18,6 +20,11 @@
     "better-sqlite3": "^11.0.0",
     "dotenv": "^16.3.1",
     "ws": "^8.16.0",
+  "@typescript-eslint/eslint-plugin": "^7.0.2",
+  "@typescript-eslint/parser": "^7.0.2",
+  "eslint": "^8.57.0",
+    "eslint-config-prettier": "^9.1.0",
+    "prettier": "^3.3.3",
     "pg": "^8.11.3"
   },
   "devDependencies": {

CollabTableServer/src/db.ts

@@ -1,6 +1,6 @@
 import dotenv from 'dotenv';
 import BetterSqlite3, { Database as SqliteDB } from 'better-sqlite3';
-import { Pool, PoolClient, QueryResult } from 'pg';
+import { Pool, PoolClient, QueryResult, types as pgTypes } from 'pg';
 import path from 'path';
 import fs from 'fs';
 
@@ -129,6 +129,9 @@ class PostgresAdapter implements DBAdapter {
   private pool: Pool;
 
   constructor() {
+    // Ensure BIGINT (int8) is parsed as number to avoid string timestamps
+    // OID 20 = INT8, OID 1700 = NUMERIC (keep default for now)
+    pgTypes.setTypeParser(20, (val: string) => parseInt(val, 10));
     const connectionString = process.env.DATABASE_URL;
     if (connectionString) {
       this.pool = new Pool({ connectionString });

CollabTableServer/src/routes/webRoutes.ts

@@ -313,9 +313,26 @@ router.get('/web/data', async (req: Request, res: Response) => {
     const values = await dbAdapter.queryAll('SELECT * FROM item_values');
     
     // Convert isDeleted from INTEGER to BOOLEAN
-    const formattedLists = (lists as any[]).map(list => ({ ...list, isDeleted: !!list.isDeleted }));
+        // Coerce timestamps to numbers (pg may return strings)
-    const formattedFields = (fields as any[]).map(field => ({ ...field, isDeleted: !!field.isDeleted }));
+        const toNum = (v: any) => (typeof v === 'string' ? Number(v) : v);
-    const formattedItems = (items as any[]).map(item => ({ ...item, isDeleted: !!item.isDeleted }));
+        const formattedLists = (lists as any[]).map(list => ({
+            ...list,
+            isDeleted: !!list.isDeleted,
+            createdAt: toNum(list.createdAt),
+            updatedAt: toNum(list.updatedAt)
+        }));
+        const formattedFields = (fields as any[]).map(field => ({
+            ...field,
+            isDeleted: !!field.isDeleted,
+            createdAt: toNum(field.createdAt),
+            updatedAt: toNum(field.updatedAt)
+        }));
+        const formattedItems = (items as any[]).map(item => ({
+            ...item,
+            isDeleted: !!item.isDeleted,
+            createdAt: toNum(item.createdAt),
+            updatedAt: toNum(item.updatedAt)
+        }));
     
     res.json({
       lists: formattedLists,