Entry Point

In Sealos DevBox, entrypoint.sh is a special script file that defines how your application starts after deployment. This guide will help you understand how to properly configure this file to ensure your application starts and runs correctly in the deployment environment.

What is entrypoint.sh

In a DevBox project, entrypoint.sh is your application's entry point that:

• Defines the startup command for your application
• Executes automatically after application deployment
• Ensures your application starts correctly
• Serves as a key component when publishing your project as an OCI image

Building in the Development Environment

Before configuring entrypoint.sh, complete your application build in the development environment. This approach:

• Reduces application startup time
• Avoids installing build dependencies in production
• Ensures you're deploying verified build artifacts

# Next.js app
npm run build  # generates .next directory
 
# TypeScript app
npm run build  # generates dist directory
 
# Go app
go build -o main  # generates executable

# Check build directory
ls -l dist/  # or .next/, build/, etc.
 
# Test build artifacts
node dist/main.js  # or other startup command

#!/bin/bash
# Next.js
NODE_ENV=production node .next/standalone/server.js
 
# TypeScript Node.js
node dist/main.js
 
# Go
./main

Common Configuration Scenarios

Pre-built Web Applications

#!/bin/bash
# Next.js (pre-built)
NODE_ENV=production node .next/standalone/server.js
 
# Vue (pre-built)
node server/index.js
 
# React (pre-built)
serve -s build -l 3000

Compiled Backend Services

#!/bin/bash
# Go (compiled)
./main
 
# Java (packaged)
java -jar app.jar
 
# Rust (compiled)
./server

Interpreted Backend Services

#!/bin/bash
# Python
python app.py
 
# Node.js (pre-built)
node dist/index.js
 
# PHP
php -S 0.0.0.0:8000

Best Practices

Common Issues

Build-related Problems

If you encounter build-related issues:

1. Ensure all build steps are completed in the development environment
2. Check that build artifacts are complete
3. Verify runtime dependencies for your build artifacts

Startup Failures

If your application fails to start:

1. Check if the startup command points to the correct build artifacts
2. Confirm all required environment variables are configured
3. Review application logs for detailed error information

Permission Issues

If you encounter permission errors:

• Ensure entrypoint.sh has execution permissions:

chmod +x entrypoint.sh

• Check if the permissions for build artifacts are correct

Testing and Validation

Before publishing your application:

1. Complete the build in the development environment
2. Test the build artifacts
3. Verify that entrypoint.sh starts your application correctly:

./entrypoint.sh

Next Steps

After completing your application build and configuring entrypoint.sh, you're ready to publish your application. During the publishing process:

1. Ensure all build artifacts are correctly generated
2. The system will use your configured entrypoint.sh as the application's startup entry point
3. After publishing is complete, during the deployment phase, your application will start according to the method defined in entrypoint.sh