Configuration File

The andasy.hcl configuration file is the central place where you define how your application should be deployed on Andasy. This file uses HCL (HashiCorp Configuration Language), a human-readable configuration language that's easy to write and understand.

The configuration file is typically created automatically when you run andasy setup, but you can also create or modify it manually to customize your deployment. It defines various aspects of your server deployment including resource allocation, networking, and storage.

Configuration Structure

The configuration file is written in HCL format and defines the following main components:

• Top-level application name - Identifies your application on the platform
• Application block - Contains the detailed deployment configuration:
  • Environment variables - Key-value pairs available to your application at runtime
  • Port settings - The port your application listens on for incoming connections
  • Compute resources - CPU and memory allocation for your application
  • Process specifications - How your application process is named and managed
  • Storage requirements - Persistent storage volumes attached to your application (optional)

Basic Configuration

app_name = "app"

app {
  env = {}
  port = 80
  
  compute {
    cpu = 1
    memory = 256
    cpu_kind = "shared"
  }
  
  process {
    name = "app"
  }
  
  storage {
    name = <volume-name>
    destination = <mountpoint>
  }
}

Configuration Reference

Top-Level Parameters

Application Block Parameters

The app block contains the primary configuration for your application deployment. This block defines how your application runs, what resources it has access to, and how it communicates.

Compute Configuration

The compute block defines the computational resources (CPU and memory) allocated to your application. These settings determine how much processing power and RAM your application has available.

Process Configuration

The process block defines how your application process is identified and managed. The process name is used for monitoring, logging, and process management.

Storage Configuration

The storage block defines persistent storage volumes that are attached to your application. Persistent storage retains data even when your application restarts or machines are recreated, making it essential for databases, file uploads, or any data that must survive restarts.

This block is optional. Only include it if you need persistent storage. You must create the volume first using andasy volumes create before referencing it here.

Usage Examples

Basic Web Server

app_name = "web-server"

app {
  env = {
    NODE_ENV = "production"
  }
  port = 80
  
  compute {
    cpu = 1
    memory = 512
    cpu_kind = "shared"
  }
  
  process {
    name = "web"
  }
}

API Server with Storage

app_name = "api-server"

app {
  env = {
    DEBUG = "true"
    LOG_LEVEL = "info"
  }
  port = 8080
  
  compute {
    cpu = 2
    memory = 1024
    cpu_kind = "shared"
  }
  
  process {
    name = "api"
  }
  
  storage {
    name = "data-volume"
    destination = "/app/data"
  }
}

Best Practices

1. Resource Allocation: Match CPU and memory settings to your application's actual needs to optimize costs.

2. Environment Variables: Use environment variables for configuration that might change between deployments.

3. Process Naming: Use descriptive process names to make monitoring and debugging easier.

4. Port Configuration: Ensure the port specified matches the port your application listens on.

5. Storage: Only use persistent storage when necessary, as it may increase costs and complexity.

Common Issues and Troubleshooting

Application Not Starting

• Verify that the port setting matches what your application is configured to use
• Check that the memory allocation is sufficient for your application
• Ensure any required environment variables are properly set in the env map

Storage Issues

• Confirm the destination path is accessible by your application
• Verify your application has appropriate permissions to read/write to the mounted volume
• Ensure the name references a valid storage volume

Conclusion

This HCL configuration format provides a clean and declarative way to define your HTTP server deployments in cloud environments. By properly configuring compute resources, networking, and storage, you can ensure your application runs efficiently and reliably.