Getting Started

Let's try deploying an application using Dewy. This article explains the basic usage and actual deployment process step by step.

Prerequisites

Dewy is installed (see Installation Guide)
For binary/asset deployment: Go application or assets are published on GitHub Releases, S3, or GCS
For container deployment: Docker or Podman is installed and running
Required environment variables are configured (GitHub token, Docker credentials, etc.)

Basic Usage

Server Application Deployment

Example of automatically deploying a server application from GitHub Releases:

# Set environment variables
export GITHUB_TOKEN=your_github_token

# Start server application
dewy server --registry ghr://owner/repo --port 8000 -- /opt/myapp/current/myapp

In this example:

ghr://owner/repo: GitHub Releases registry URL
--port 8000: Port used by the application
/opt/myapp/current/myapp: Path to the application to execute

Static Asset Deployment

For deploying static files like HTML, CSS, and JavaScript files:

dewy assets --registry ghr://owner/frontend-assets

Container Image Deployment

For deploying containerized applications with zero-downtime rolling update deployment:

# Authenticate if using private registry
docker login ghcr.io

# Deploy container image from OCI registry (auto-detect container port)
dewy container --registry img://ghcr.io/owner/app --port 8080

# Or specify explicit port mapping (proxy:container)
dewy container --registry img://ghcr.io/owner/app --port 8080:3000

In this example:

img://ghcr.io/owner/app: OCI registry URL (supports Docker Hub, GHCR, GCR, ECR, etc.)
--port 8080: Proxy listens on port 8080, container port auto-detected from Docker image
--port 8080:3000: Proxy listens on 8080, forwards to container port 3000
Health check path can be specified with --health-path /health (optional)

Dewy automatically:

Performs rolling update deployment with zero downtime
Switches traffic to the new container after health checks pass
Removes the old container after the drain period

Actual Deployment Example

Example Using GitHub Releases

# Configure GitHub Personal Access Token
export GITHUB_TOKEN=ghp_xxxxxxxxxxxxxxxxxxxx

# Create application directory
sudo mkdir -p /opt/myapp
sudo chown $USER:$USER /opt/myapp
cd /opt/myapp

# Start Dewy to deploy server application
dewy server \
  --registry ghr://myorg/myapp \
  --port 8080 \
  --log-level info \
  -- /opt/myapp/current/myapp

Example Using OCI Registry

# Authenticate if using private registry
docker login ghcr.io

# Ensure Docker/Podman is running
docker info

# Deploy container image with rolling update deployment
dewy container \
  --registry img://ghcr.io/myorg/myapp \
  --port 8080:3000 \
  --health-path /health \
  --health-timeout 30 \
  --drain-time 30 \
  --log-level info

In this example:

Dewy polls the OCI registry for new image versions
When a new version is detected, it pulls the image and starts a new container
The new container is health-checked (if --health-path is specified)
Traffic is switched to the new container by the proxy
The old container continues running during the drain period, then is removed
The process repeats automatically when new versions are published

The proxy listens on the specified port and forwards traffic to the current container. You can expose this port through a reverse proxy like nginx or Caddy.

Next Steps

For more information, refer to the following documentation: