Java Electerm Sync Server

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A simple, lightweight data synchronization server for Electerm, built with Java and Spark. It provides a REST API for syncing bookmarks, history, and other data across Electerm instances.

Prerequisites

• Java 17: Required for building and running the server. Download from Adoptium or your preferred JDK provider.
• Gradle: Included via the Gradle Wrapper (gradlew), so no separate installation needed.
• Git: For cloning the repository.

Installation

1. Clone the repository:

   git clone https://github.com/electerm/electerm-sync-server-java.git
   cd electerm-sync-server-java

2. Set up the environment file:

   cp sample.env .env

   Edit .env with your preferred settings (see Configuration below).

Configuration

The server uses environment variables from a .env file for configuration. Key settings include:

• JWT_SECRET: A secret key for JWT token signing (generate a strong random string).
• JWT_USER_NAME: Username for authentication.
• JWT_USER_PASSWORD: Password for authentication.
• PORT: Server port (default: 7837).
• DB_URL: H2 database URL (default: embedded database).

Example .env:

JWT_SECRET=your-super-secret-key-here
JWT_USER_NAME=admin
JWT_USER_PASSWORD=securepassword
PORT=7837
DB_URL=jdbc:h2:./electerm_sync_db

Security Note: Never commit .env to version control. Use strong, unique values for secrets.

Running the Server

Development Mode

For quick testing or development:

./gradlew run

• Starts the server on http://127.0.0.1:7837.
• Output will show: server running at http://127.0.0.1:7837.
• Press Ctrl+C to stop.

Production Mode

1. Build the application:

   ./gradlew build

2. Extract the distribution:

   tar -xvf build/distributions/electerm-sync-server-java.tar
   cd electerm-sync-server-java

3. Run the server:

   ./bin/electerm-sync-server-java

   • Runs in the foreground. Use & to background it: ./bin/electerm-sync-server-java &.
   • Access at http://127.0.0.1:7837 (or your configured port).

Using with Electerm

1. In Electerm, go to Settings > Sync.
2. Select Custom Sync Server.
3. Set:
   • Server URL: http://127.0.0.1:7837 (or your server's URL).
   • JWT Secret: The JWT_SECRET from your .env.
   • Username: The JWT_USER_NAME from your .env.
4. Save and sync your data.

The API endpoint is http://127.0.0.1:7837/api/sync.

Testing

Run the test suite:

./gradlew test

• Uses JUnit for unit tests.
• Reports are in build/reports/tests/test/index.html.

Customization

Writing Your Own Data Store

The server uses an H2 database by default, but you can implement custom storage.

1. Implement the data store interface by extending or referencing DataStore.java.
2. Update App.java to use your custom store.
3. Rebuild and run.

Example: Take src/main/java/ElectermSync/DataStore.java as a reference for read/write methods.

Docker

For containerized deployment, see electerm-sync-server-java-docker.

Sync Servers in Other Languages

Explore alternatives: Custom Sync Server Wiki.

License

MIT