How to Configure MongoDB in Dropwizard

July 29, 2025

Dropwizard offers a solid foundation for building RESTful Java applications, and MongoDB makes working with document data flexible and fast. We’ll walk through setting up MongoDB in Dropwizard:

Local development with Docker and config-dev.yml
Production deployment on Kubernetes using config-prod.yml, ConfigMaps, and Secrets
A minimal Maven setup with Dropwizard, MongoDB, and Kubernetes support

Let’s get started!

1. Add Dependencies in `pom.xml`

First, add these essential libraries so your app can connect to MongoDB and optionally integrate with Kubernetes:

<dependencies>
  <!-- Dropwizard core -->
  <dependency>
    <groupId>io.dropwizard</groupId>
    <artifactId>dropwizard-core</artifactId>
    <version>${dropwizard.version}</version>
  </dependency>

  <!-- MongoDB Java Driver -->
  <dependency>
    <groupId>org.mongodb</groupId>
    <artifactId>mongo-java-driver</artifactId>
    <version>3.12.0</version>
  </dependency>

  <!-- Fabric8 Kubernetes client (optional) -->
  <dependency>
    <groupId>io.fabric8</groupId>
    <artifactId>kubernetes-client</artifactId>
    <version>${fabric8.version}</version>
  </dependency>
</dependencies>

These enable Dropwizard essentials, secure MongoDB access, and Kubernetes support.

2. Run MongoDB Locally with Docker

For local development, spin up a MongoDB container:

version: '3.8'
services:
  mongo:
    image: mongo:5.0
    ports:
      - "27017:27017"
    volumes:
      - mongo-data:/data/db

volumes:
  mongo-data:

Run:

docker-compose up -d

Your MongoDB instance will then be available at mongodb://localhost:27017.

3. Configure Dev Setup: `config-dev.yml`

Create a configuration file for development:

server:
  applicationConnectors:
    - type: http
      port: 8080

mongo:
  host: localhost
  port: 27017
  database: devdb

You’ll need a corresponding config POJO:

public class MongoConfig {
  @JsonProperty public String host;
  @JsonProperty public int port;
  @JsonProperty public String database;
}

public class AppConfig extends Configuration {
  @JsonProperty("mongo")
  public MongoConfig mongo = new MongoConfig();
}

Initialize your Mongo client in the Application class:

String uri = String.format("mongodb://%s:%d", config.mongo.host, config.mongo.port);
MongoClient mongoClient = new MongoClient(new MongoClientURI(uri));
DB db = mongoClient.getDB(config.mongo.database);

Run your app locally:

java -jar target/myapp.jar server config-dev.yml

4. Prepare Kubernetes for Production

Keep production settings secure using Kubernetes resources:

kubectl create configmap mongo-config \
  --from-literal=MONGO_HOST=mongo-service \
  --from-literal=MONGO_PORT=27017 \
  --from-literal=MONGO_DATABASE=proddb

kubectl create secret generic mongo-secret \
  --from-literal=MONGO_USER=produser \
  --from-literal=MONGO_PASSWORD=prodpass

This creates ConfigMap and Secret for audi configuration and credentials.

5. Define Production Config: `config-prod.yml`

Use environment-based variables so your app picks up prod settings at runtime:

server:
  applicationConnectors:
    - type: http
      port: 8080

mongo:
  host: ${MONGO_HOST}
  port: ${MONGO_PORT}
  database: ${MONGO_DATABASE}
  user: ${MONGO_USER}
  password: ${MONGO_PASSWORD}

Dropwizard will automatically inject these values.

6. Kubernetes Deployment Snippet

Ensure your Kubernetes manifest references the ConfigMap and Secret:

env:
  - name: MONGO_HOST
    valueFrom:
      configMapKeyRef:
        name: mongo-config
        key: MONGO_HOST
  - name: MONGO_PORT
    valueFrom:
      configMapKeyRef:
        name: mongo-config
        key: MONGO_PORT
  - name: MONGO_DATABASE
    valueFrom:
      configMapKeyRef:
        name: mongo-config
        key: MONGO_DATABASE
  - name: MONGO_USER
    valueFrom:
      secretKeyRef:
        name: mongo-secret
        key: MONGO_USER
  - name: MONGO_PASSWORD
    valueFrom:
      secretKeyRef:
        name: mongo-secret
        key: MONGO_PASSWORD

Start your app:

java -jar myapp.jar server config-prod.yml

7. Why This Pattern Works

Rapid local builds with Docker and dev config
Secure and scalable production using Kubernetes ConfigMaps and Secrets
Clear separation between development and production environments
Easily extendable structure to handle users, retries, indexes, or replicas

Following this setup, you get a fast local development loop, production readiness, and clear environment boundaries. Your Dropwizard service is now seamlessly integrated with MongoDB—locally via Docker, and securely in the cloud via Kubernetes. It’s a clean, maintainable, and robust foundation for real-world applications.

1. Add Dependencies in pom.xml