Task Engineering Engine

A high-performance full-stack task management monorepo designed with a decoupled architectural framework. The system separates client presentation from server-side business logic, enabling independent development, testing, and deployment of each layer while maintaining a clear API contract between them.

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Key Features

Capability	Description
Async architecture	Non-blocking Express controllers with async/await Prisma operations for scalable request handling
Real-time logging middleware	Global request logger captures HTTP method, URL path, and ISO timestamp on every inbound request
Automated Jest integration testing	Supertest-powered API tests validate creation, validation, and pagination behavior against a live Express instance
Prisma ORM data persistence	Type-safe database access with SQLite, schema migrations, and UUID primary keys
Dynamic frontend controls	Vanilla JS dashboard with status filtering, paginated task lists, and resilient error handling when the API is offline

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Repository Structure

task-engine-backend/
├── backend/                  # Node.js / Express API
│   ├── prisma/               # Schema, migrations, SQLite database
│   ├── src/
│   │   ├── controllers/      # Request handlers
│   │   ├── middlewares/      # Logger and cross-cutting concerns
│   │   ├── models/           # Prisma data-access layer
│   │   ├── routes/           # Express route definitions
│   │   ├── app.js            # Express application (exported for tests)
│   │   └── server.js         # HTTP server entry point
│   └── tests/                # Jest integration test suite
└── frontend/                 # Static client dashboard
    ├── index.html
    └── app.js

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System Architecture

┌─────────────────────────────────────────────────────────────────────────┐
│                         FRONTEND CLIENT                                 │
│              (frontend/index.html + app.js)                             │
│                                                                         │
│   • Task creation form          • Status filter dropdown                │
│   • Paginated task cards        • fetch() → http://localhost:5000       │
└───────────────────────────────────┬─────────────────────────────────────┘
                                    │
                                    │  HTTP (CORS-enabled)
                                    ▼
┌─────────────────────────────────────────────────────────────────────────┐
│                      EXPRESS ROUTING LAYER                              │
│                         (src/routes/)                                   │
│                                                                         │
│   GET  /health                                                          │
│   GET  /api/tasks          POST /api/tasks                              │
└───────────────────────────────────┬─────────────────────────────────────┘
                                    │
                                    ▼
┌─────────────────────────────────────────────────────────────────────────┐
│                         MIDDLEWARE STACK                                │
│                                                                         │
│   cors()  →  logger  →  express.json()                                  │
└───────────────────────────────────┬─────────────────────────────────────┘
                                    │
                                    ▼
┌─────────────────────────────────────────────────────────────────────────┐
│                          CONTROLLERS                                    │
│                      (src/controllers/)                                 │
│                                                                         │
│   createTask()          getAllTasks()                                     │
│   • Validates payload   • Parses page / limit / status query params       │
│   • Returns 201/400     • Returns 200 with filtered, paginated results  │
└───────────────────────────────────┬─────────────────────────────────────┘
                                    │
                                    ▼
┌─────────────────────────────────────────────────────────────────────────┐
│                       MODEL / DATA ACCESS                               │
│                        (src/models/)                                    │
│                                                                         │
│   prisma.task.create()          prisma.task.findMany()                  │
└───────────────────────────────────┬─────────────────────────────────────┘
                                    │
                                    ▼
┌─────────────────────────────────────────────────────────────────────────┐
│                    PRISMA ORM  →  SQLite                                │
│                      (prisma/dev.db)                                    │
│                                                                         │
│   Task { id, title, description, status, createdAt }                    │
└─────────────────────────────────────────────────────────────────────────┘

---

API Endpoint Contract

Base URL: http://localhost:5000

GET /health

System status check.

Method	GET
Auth	None
Success	200 OK

Response body

{ "status": "ok" }

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GET /api/tasks

Retrieve a paginated, optionally filtered list of tasks.

Method	GET
Auth	None
Success	200 OK

Query parameters

Parameter	Type	Default	Description
page	integer	1	Page number (1-indexed). Offset is calculated as (page - 1) × limit.
limit	integer	10	Maximum number of tasks returned per page.
status	string	(none)	Optional filter. When provided, only tasks matching the status are returned (e.g. pending, completed).

Example request

GET /api/tasks?page=1&limit=5&status=pending

Example response

[
  {
    "id": "282ff51d-af4d-4269-8b8a-852b735a46e5",
    "title": "Review pull request",
    "description": "Check API changes before merge",
    "status": "pending",
    "createdAt": "2026-05-31T14:25:49.186Z"
  }
]

---

POST /api/tasks

Create a new task.

Method	POST
Auth	None
Content-Type	application/json
Success	201 Created
Validation error	400 Bad Request

Request body

Field	Type	Required	Default	Rules
title	string	Yes	—	Must be present and non-empty. Returns 400 if missing.
description	string	No	null	Optional free-text description.
status	string	No	"pending"	Set automatically by the server on creation. Not accepted from the client payload.

Example request

{
  "title": "Deploy staging environment",
  "description": "Run migration and smoke tests"
}

Example success response (201)

{
  "id": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
  "title": "Deploy staging environment",
  "description": "Run migration and smoke tests",
  "status": "pending",
  "createdAt": "2026-05-31T14:30:00.000Z"
}

Example error response (400)

{ "error": "Title is required" }

---

Quick Start

Prerequisites

• Node.js v18 or later
• npm

Backend Setup

cd backend
npm install

Create a .env file in the backend/ directory (if one does not already exist):

DATABASE_URL="file:./dev.db"

Apply database migrations and generate the Prisma client:

npx prisma migrate dev

Start the development server with hot reload:

npm run dev

The API listens on port 5000 by default. You should see:

Server listening on port 5000

Note: If the port is already in use, stop the conflicting process or set a different port in .env (e.g. PORT=5001).

Frontend Setup

With the backend running, open the dashboard in your browser:

frontend/index.html

You can open the file directly from your file explorer, or serve it locally:

cd frontend
npx serve .

The client communicates with the API at http://localhost:5000 and displays connection status, task cards, status filters, and pagination controls.

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Automation Testing Suite

Integration tests live in backend/tests/ and run against the exported Express app (no live server port required).

From the backend/ directory:

npm test

This executes Jest with Supertest and validates:

• POST /api/tasks returns 201 with valid payload
• POST /api/tasks returns 400 when title is missing
• GET /api/tasks pagination returns the correct number of limited items

For verbose output:

npx jest --verbose

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Technology Stack

Layer	Technologies
API	Node.js, Express 5, CORS
Database	SQLite, Prisma ORM
Testing	Jest, Supertest
Frontend	HTML, Tailwind CSS (CDN), Vanilla JavaScript
Dev tooling	nodemon, dotenv

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License

ISC