Server Configuration#

This page provides detailed information on how to configure Bun Expo Updates Server, including environment variables, Redis configuration, object storage settings, and more.

Environment Variable Configuration#

Bun Expo Updates Server uses environment variables for configuration. You can set these variables using a .env file or directly in your environment. Here are all available environment variables:

Basic Configuration#

Redis Configuration#

Client Project Configuration#

Code Signing Configuration#

Object Storage Service (OSS) Configuration#

*Note: Some variables may be required depending on the selected OSS provider.

.env File Example#

Here's an example of a complete .env file:

# Redis Configuration
REDIS_URL=redis://localhost:6379

# Log Settings
DEBUG=true
LOG_LANGUAGE=en-US

# OSS (Object Storage Service) Configuration
OSS_PROVIDER=dogecloud
OSS_ACCESS_KEY=your_access_key
OSS_SECRET_KEY=your_secret_key
OSS_FORCE_PATH_STYLE=0
# OSS_REGION=your_region
# OSS_BUCKET=your_bucket
# OSS_ENDPOINT=your_endpoint

# Client Project Path
CLIENT_PROJECT_PATH=/path/to/your/client/project

# Private Key Path Configuration
PRIVATE_KEY_PATH=code-sign-keys/private-key.pem

# Server Port Configuration
port=3001

# Update Resource Download URL
HOSTNAME=https://your-update-domain.com

Redis Configuration#

Redis is used for caching update manifests and other server states. Ensure you have a Redis instance available and configured via the REDIS_URL environment variable.

Redis Connection Format#

Examples:

• redis://localhost:6379 - Connect to local Redis with no password
• redis://:password123@redis-server:6379 - Connect to Redis server with password
• redis://username:password@redis-server:6379/1 - Using username, password, and specific database

Code Signing#

The Expo Updates protocol supports code signing to verify update integrity. To enable code signing, you need to generate a key pair and configure the private key path:

Generate Key Pair#

# Create directory
mkdir -p code-sign-keys

# Generate private key
openssl genrsa -out code-sign-keys/private-key.pem 2048

# Generate public key from private key
openssl rsa -in code-sign-keys/private-key.pem -pubout -out code-sign-keys/public-key.pem

Set the PRIVATE_KEY_PATH environment variable to the path of your private key:

PRIVATE_KEY_PATH=code-sign-keys/private-key.pem

In your Expo client configuration, add the public key configuration:

{
  "expo": {
    "updates": {
      "url": "https://your-server-url.com/api/manifest",
      "codeSigningPublicKeyBase64": "Your public key (Base64 encoded)",
      "enabled": true,
      "checkAutomatically": "ON_LOAD"
    }
  }
}

To get the Base64 encoded public key, you can run:

cat code-sign-keys/public-key.pem | grep -v "PUBLIC KEY" | tr -d '\n'

Object Storage (OSS) Configuration#

The server supports multiple object storage services for storing update files. Configure the required environment variables based on your chosen provider:

DogeCloud Configuration#

OSS_PROVIDER=dogecloud
OSS_ACCESS_KEY=your_access_key
OSS_SECRET_KEY=your_secret_key

Qiniu Cloud Configuration#

OSS_PROVIDER=qiniu
OSS_ACCESS_KEY=your_access_key
OSS_SECRET_KEY=your_secret_key
OSS_REGION=your_region
OSS_BUCKET=your_bucket

AWS S3 Configuration#

OSS_PROVIDER=s3
OSS_ACCESS_KEY=your_access_key
OSS_SECRET_KEY=your_secret_key
OSS_REGION=your_region
OSS_BUCKET=your_bucket
OSS_ENDPOINT=your_endpoint
OSS_FORCE_PATH_STYLE=0

Custom OSS Provider#

To use a custom OSS provider, see the OSS Adapters section for information on how to implement and register a custom adapter.

Production Environment Configuration#

In a production environment, it is recommended to:

1. Disable debug logs:

   DEBUG=false

2. Use secure Redis configuration, including password and TLS:

   REDIS_URL=redis://:your-password@your-redis-host:6379

3. Ensure HOSTNAME uses HTTPS:

   HOSTNAME=https://your-production-domain.com

4. Consider using environment variable management tools like Docker Secrets or cloud platform environment variable management features instead of directly using .env files.

Advanced Configuration#

Multiple Client Project Configuration#

If you need to manage updates for multiple client projects, you can switch the CLIENT_PROJECT_PATH as needed:

# Upload updates for project 1
CLIENT_PROJECT_PATH=/path/to/project1 bun src/scripts/upload.ts

# Upload updates for project 2
CLIENT_PROJECT_PATH=/path/to/project2 bun src/scripts/upload.ts

Performance Tuning#

For high-traffic scenarios, consider:

1. Increasing Redis connection pool size
2. Using a CDN to distribute update files
3. Configuring appropriate resource limits for the server

For more advanced configuration options, refer to the relevant module documentation in the server source code.