Upgrade Flower and Dependencies

.gitignore

@@ -0,0 +1,24 @@
+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+
+# Distribution / packaging
+.Python
+.venv
+env/
+bin/
+build/
+develop-eggs/
+dist/
+eggs/
+lib64/
+parts/
+sdist/
+var/
+.vscode/
+*.egg-info/
+.installed.cfg
+*.egg
+
+# vim
+*.swp

README.md

@@ -1,8 +1,66 @@
-# Celery on Render
+# Celery Task Queue with Flower
 
-This repo can be used to deploy the [Celery](https://github.com/celery/celery) distributed task queue on [Render](https://render.com). It also includes deployment instructions for [Flower](https://github.com/mher/flower), a web monitoring frontend for Celery.
+A modern Flask + Celery distributed task queue with Flower monitoring dashboard.
 
+## Tech Stack
+
+- **Flask 3.0** - Web framework
+- **Celery 5.3** - Distributed task queue
+- **Flower 2.0** - Real-time Celery monitoring
+- **Redis** - Message broker & result backend
+
+## Local Development
+
+### Prerequisites
+
+- Python 3.10+
+- Redis server running locally
+
+### Setup
+
+```bash
+# Create virtual environment
+python -m venv venv
+source venv/bin/activate  # On Windows: venv\Scripts\activate
+
+# Install dependencies
+pip install -r requirements.txt
+
+# Set environment variables (optional)
+export CELERY_BROKER_URL=redis://localhost:6379/0
+export CELERY_RESULT_BACKEND=redis://localhost:6379/0
+export FLASK_SECRET_KEY=your-secret-key
+```
+
+### Running
+
+Start each service in a separate terminal:
+
+```bash
+# Terminal 1: Start Redis (if not running as a service)
+redis-server
+
+# Terminal 2: Start Celery worker
+celery -A tasks worker --loglevel=info
+
+# Terminal 3: Start Flower monitoring
+celery -A tasks flower --port=5555
+
+# Terminal 4: Start Flask app
+flask run
+```
+
+Then visit:
+- **Web App**: http://localhost:5000
+- **Flower Dashboard**: http://localhost:5555
 
 ## Deployment
 
-Follow the guide at https://render.com/docs/deploy-celery.
+Follow the guide at https://render.com/docs/deploy-celery for production deployment on Render.
+
+## Features
+
+- Asynchronous task execution
+- Real-time task monitoring via Flower
+- Task result tracking with Redis backend
+- Modern, responsive UI

app.py

@@ -1,20 +1,29 @@
 import os
-from flask import Flask, flash, render_template, redirect, request
+
+from flask import Flask, flash, redirect, render_template, request
+
 from tasks import add
 
 app = Flask(__name__)
-app.secret_key = os.getenv('FLASK_SECRET_KEY', "super-secret")
+app.secret_key = os.getenv("FLASK_SECRET_KEY", "super-secret")
 
 
-@app.route('/')
+@app.route("/")
 def main():
-    return render_template('main.html')
+    return render_template("main.html")
 
 
-@app.route('/add', methods=['POST'])
+@app.route("/add", methods=["POST"])
 def add_inputs():
-    x = int(request.form['x'])
-    y = int(request.form['y'])
-    add.delay(x, y)
-    flash("Your addition job has been submitted.")
-    return redirect('/')
+    try:
+        x = int(request.form["x"])
+        y = int(request.form["y"])
+        result = add.delay(x, y)
+        flash(f"Job submitted! Task ID: {result.id[:8]}...")
+    except (ValueError, KeyError):
+        flash("Please enter valid numbers for both X and Y.")
+    return redirect("/")
+
+
+if __name__ == "__main__":
+    app.run(debug=True)

requirements.txt

@@ -1,9 +1,6 @@
-celery==4.3.0
-Flask==1.0.2
-flower==0.9.3
-gunicorn==19.9.0
-redis==3.2.1
-
-# NOTE: Kombu 4.6.5 results in a build failure. Bumping down to 4.6.4
-#       See this github issue: https://github.com/celery/kombu/issues/1063
-kombu==4.6.4
+celery==5.3.6
+Flask==3.0.0
+flower==2.0.1
+gunicorn==21.2.0
+redis==5.0.1
+kombu==5.3.4

tasks.py

@@ -1,9 +1,27 @@
 import os
+
 from celery import Celery
 
-app = Celery('tasks', broker=os.getenv("CELERY_BROKER_URL"))
+# Configure Celery with broker and optional result backend
+app = Celery(
+    "tasks",
+    broker=os.getenv("CELERY_BROKER_URL", "redis://localhost:6379/0"),
+    backend=os.getenv("CELERY_RESULT_BACKEND", "redis://localhost:6379/0"),
+)
+
+# Celery configuration
+app.conf.update(
+    task_serializer="json",
+    accept_content=["json"],
+    result_serializer="json",
+    timezone="UTC",
+    enable_utc=True,
+    task_track_started=True,
+    result_expires=3600,
+)
 
 
-@app.task
-def add(x, y):
+@app.task(bind=True)
+def add(self, x, y):
+    """Add two numbers asynchronously."""
     return x + y

templates/main.html

@@ -34,4 +34,4 @@ <h1 class="mb-5">Asynchronous addition using Celery!</h1>
     </div>
 </div>
 </body>
-</html>
+</html>