Deploying a Flask App on Akash

Here’s a step-by-step guide on how to create and deploy a Flask application on the Akash decentralized cloud using the sample SDL template. This guide assumes you have basic knowledge of Flask and are familiar with Docker and the Akash ecosystem.

Prerequisites

1. Install Akash CLI: Ensure the Akash CLI (akash) is installed and configured on your system.
2. Set Up Wallet: Create an Akash wallet and fund it with AKT tokens.
3. Docker Installed: Have Docker installed for containerizing your Flask app.
4. Basic Flask App: Have a working Flask application.

Step 1: Prepare Your Flask App

1. Create a Flask App Structure: Your Flask app should look something like this:

my-flask-app/
├── app/
│   ├── __init__.py
│   ├── routes.py
├── Dockerfile
├── requirements.txt
├── config.py
└── wsgi.py

2. Create the Dockerfile: Create a Dockerfile to containerize your application. Example:

FROM python:3.9-slim

WORKDIR /app

COPY requirements.txt requirements.txt
RUN pip install -r requirements.txt

COPY . .

CMD ["gunicorn", "-w", "4", "-b", "0.0.0.0:5000", "wsgi:app"]

3. **Install Dependencies Create a requirements.txt file with the necessary Flask dependencies:

Flask==2.3.2
gunicorn==21.2.0

Step 2: Containerize the Application

1. Build the Docker Image In the project root directory, run:

docker build -t my-flask-app .

2. Test Locally Run the container to ensure it works:

docker run -p 5000:5000 my-flask-app

Step 3: Prepare the SDL File

Below is a sample SDL template tailored for a Flask app:

version: "2.0"

services:
  flask-service:
    image: your-dockerhub-username/my-flask-app:latest
    expose:
      - port: 5000
        as: 80
        to:
          - global: true

profiles:
  compute:
    flask-compute:
      resources:
        cpu:
          units: 1
        memory:
          size: 512Mi
        storage:
          size: 1Gi
  placement:
    akash:
      attributes:
        host: akash
      signedBy:
        anyOf:
          - "akash1xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
      pricing:
        flask-compute:
          denom: uakt
          amount: 100

deployment:
  flask-deployment:
    flask-service:
      profile: flask-compute
      count: 1

Step 4: Push Your Docker Image

1. Tag Your Image

docker tag my-flask-app your-dockerhub-username/my-flask-app:latest

2. Push to DockerHub

docker push your-dockerhub-username/my-flask-app:latest

Step 5: Deploy on Akash

1. Create Deployment Use the Akash CLI to create the deployment:

akash tx deployment create deploy.yaml --from <your-wallet-name> --node <node-url> --chain-id <chain-id> --fees 5000uakt

2. Approve Lease After creating the deployment, view bids:

akash query market bid list --owner <your-address>

Select a provider and approve the lease:

akash tx market lease create --dseq <deployment-sequence> --from <your-wallet-name> --provider <provider-address> --node <node-url> --chain-id <chain-id> --fees 5000uakt

3. Access Your App Once the lease is approved, Akash will provide an external URL or IP for accessing the deployed Flask app.

Step 6: Verify Deployment

1. Check Logs To debug any issues:

akash logs --dseq <deployment-sequence> --gseq <group-sequence> --oseq <order-sequence>

2. Test Application Visit the external URL or IP in a browser to ensure the Flask app is running.

Optional Enhancements

• Enable HTTPS: Use a reverse proxy like NGINX with SSL certificates.
• Scaling: Adjust the count in the deployment to scale the number of instances.