A Node.js application that calls an API endpoint every hour with a frequency parameter based on the current hour's divisibility.

The application determines the frequency parameter based on which number the current hour is divisible by (in priority order):

• 24x: Hour is divisible by 24 (midnight only - hour 0)
• 12x: Hour is divisible by 12 (hours 0, 12)
• 6x: Hour is divisible by 6 (hours 0, 6, 12, 18)
• 4x: Hour is divisible by 4 (hours 0, 4, 8, 12, 16, 20)
• 3x: Hour is divisible by 3 (hours 0, 3, 6, 9, 12, 15, 18, 21)
• 2x: Hour is divisible by 2 (all even hours)
• 1x: All other hours (odd hours not divisible by 3)

• Node.js 18 or higher
• npm

1. Install dependencies:

npm install

2. Set your API endpoint (optional):

export API_ENDPOINT=https://your-api.com/endpoint

3. Run the application:

npm start

docker build -t cron-self-code .

docker run -e API_ENDPOINT=https://your-api.com/endpoint cron-self-code

1. Create a new Web Service on Render

2. Connect your Git repository

3. Configure the service:

   • Environment: Docker
   • Build Command: (leave empty, Dockerfile will be used)
   • Start Command: (leave empty, CMD in Dockerfile will be used)

4. Add Environment Variable:

   • Key: API_ENDPOINT
   • Value: Your actual API endpoint URL

5. Deploy

• Render will automatically detect the Dockerfile and build the image
• The application runs continuously and executes the API call every hour
• Make sure to set the API_ENDPOINT environment variable in Render's dashboard
• The service will call the API immediately on startup and then every hour at minute 0

The application uses the cron pattern 0 * * * * which means:

• Runs at minute 0 of every hour
• Examples: 00:00, 01:00, 02:00, etc.

The application makes a GET request to the configured endpoint with a query parameter:

GET {API_ENDPOINT}?frequency={frequency}

Example:

GET https://api.example.com/endpoint?frequency=6x

The application logs:

• Startup message
• Each cron job trigger
• Current hour and calculated frequency
• API response status and data
• Any errors that occur

The application handles SIGTERM and SIGINT signals for graceful shutdown, which is important for container orchestration platforms like Render.