Check out v4 of the Fauna CLI

v4 of the Fauna CLI is now in beta.

The new version introduces enhancements to the developer experience, including an improved authentication workflow. To get started, check out the CLI v4 quick start.

Java quick start

Use Fauna’s JVM driver to query e-commerce demo data in a Java 17 app. You’ll set up the app using Gradle.

 

  1. Create a database with demo data

    Log in to the Fauna Dashboard, and create a database with the following configuration:

    • Region Group: Choose your preferred region group, which determines where your data resides.

    • Use demo data: Enabled.

    • Enable backups: Disabled.

    Leave the other options as is.

    Create demo database

  2. Create an authentication secret

    Fauna supports several types of authentication secrets. For this quick start, create a key, which is a type of secret, with the built-in server-readonly role:

    1. In the Dashboard’s Explorer page, select your demo database.

    2. In the database’s Keys tab, click Create Key.

    3. Choose a Role of server (read-only).

    4. Click Save.

    5. Copy the Key Secret.

    Create a key

  3. Set the FAUNA_SECRET environment variable

    Set the FAUNA_SECRET environment variable to your key’s secret. Fauna’s client drivers can access the secret from this variable.

    export FAUNA_SECRET=<KEY_SECRET>

  4. Create a Gradle project

    Create a new directory for your app and initialize a Gradle project:

    mkdir example
cd example
gradle init \
  --type java-application \
  --dsl groovy \
  --test-framework junit \
  --project-name app \
  --package app \
  --java-version 17 \
  --no-incubating \
  --no-split-project

  5. Add the JVM driver as a dependency

    In the example/app directory, edit example/app/build.gradle and add the JVM driver as a dependency:

    dependencies {
    ...
    implementation "com.fauna:fauna-jvm:1.0.0"
    ...
}

  6. Create a query script

    In the example/app directory, edit the example/app/src/main/java/app/App.java file and replace the code with the following:

    package app;

import java.util.concurrent.CompletableFuture;
import java.util.concurrent.ExecutionException;

import com.fauna.client.Fauna;
import com.fauna.client.FaunaClient;
import com.fauna.exception.FaunaException;
import com.fauna.query.builder.Query;
import com.fauna.response.QuerySuccess;
import com.fauna.types.Page;

import static com.fauna.codec.Generic.pageOf;
import static com.fauna.query.builder.Query.fql;

public class App {

    // Define class for `Product` documents
    // in expected results.
    public static class Product {
        public String name;

        public String description;

        public Integer price;
    }

    public static void main(String[] args) {
        try {
            // Initialize the client to connect to Fauna
            // using the `FAUNA_SECRET` environment variable.
            FaunaClient client = Fauna.client();

            // Compose a query using an FQL template string.
            // The query calls the `Product` collection's
            // `sortedByPriceLowToHigh()` index. It projects the `name`,
            // `description`, and `price` fields covered by the index.
            Query query = fql("""
                Product.sortedByPriceLowToHigh() {
                    name,
                    description,
                    price
                }
            """);

            // Run the query.
            System.out.println("Running synchronous query:");
            runSynchronousQuery(client, query);
        } catch (FaunaException e) {
            System.err.println("Fauna error occurred: " + e.getMessage());
            e.printStackTrace();
        }
    }

    private static void runSynchronousQuery(FaunaClient client, Query query) throws FaunaException {
        // Use `query()` to run a synchronous query.
        // Synchronous queries block the current thread until the query completes.
        // Accepts the query, expected result class, and a nullable set of query options.
        QuerySuccess<Page<Product>> result = client.query(query, pageOf(Product.class));
        printResults(result.getData());
    }

    // Iterate through the products in the page.
    private static void printResults(Page<Product> page) {
        for (Product product : page.getData()) {
            System.out.println("Name: " + product.name);
            System.out.println("Description: " + product.description);
            System.out.println("Price: " + product.price);
            System.out.println("--------");
        }
        // Print the `after` cursor to paginate through results.
        System.out.println("After: " + page.getAfter());
    }
}

  7. Run the script

    Run the script from the app directory. The script prints a list of e-commerce products from the demo data in the terminal.

    ./gradlew run

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