Quick Start: Java, Spring Boot & MongoDB Template

Blog Post

The code in this repository is discussed in this blog post in the MongoDB Developer Center.

Supported versions:

• Java 21
• Spring boot 3.2.2
• MongoDB 7.0
• MongoDB Java driver 4.11.1
• Maven 3.8.7
• OpenAPI 3

MongoDB Atlas

• Get started with a Free Tier Cluster on MongoDB Atlas.
• Read this blog post: Quick Start - Getting your Free MongoDB Atlas Cluster.
• You will need to update the default MongoDB URI spring.data.mongodb.uri in the application.properties file or set an environment variable: export MONGODB_URI=mongodb://localhost:27017.

Commands

• Start the server in a console with mvn spring-boot:run.
• If you add some Unit Tests, you would start them with mvn clean test.
• You can start the end-to-end tests with mvn clean integration-test.
• You can build the project with : mvn clean package.
• You can run the project with the fat jar and the embedded Tomcat: java -jar target/java-spring-boot-mongodb-starter-1.0.0.jar but I would use a real tomcat in production.

Project Loom & Virtual Threads

• This project starter supports Virtual Threads thanks to:
  • JDK 21
  • Spring 3.2.0+.
  • spring.threads.virtual.enabled=true in the application.properties

Swagger & OpenAPI 3

• springdoc-openapi-starter-webmvc-ui library dependency is in the pom.xml.
• No configuration required.
• The Swagger UI can be seen at http://localhost:8080/swagger-ui/index.html.
• The JSON Open API documentation 3.0.1 is at http://localhost:8080/v3/api-docs.
• The YAML Open API documentation 3.0.1 is at http://localhost:8080/v3/api-docs.yaml.
• You can also try the entire REST API directly from the Swagger web interface!

Features showcase

This project showcases several features of MongoDB:

• MongoDB multi-document ACID transactions for 3 functions. See MongoDBPersonRepository.saveAll().
• MongoDB Aggregation pipeline. See MongoDBPersonRepository.getAverageAge().
• Implementation of basic CRUD queries. See MongoDBPersonRepository.java.
• MongoDB typed collection with automatic mapping to POJOs using codecs: See ConfigurationSpring.java.
• How to manipulate correctly ObjectId across, the REST API, the POJOs and the database itself. See the main trick in Person.java.

And some other cool stuff:

• You can change the default Spring Boot logo by adding a banner.txt file in your properties.
• You don't have to use Spring Data MongoDB. The MongoDB driver is more flexible and already provides everything you need to code efficiently and optimise your queries correctly.

Example API Calls

curl -X 'POST' \
  'http://localhost:8080/api/person' \
  -H 'accept: */*' \
  -H 'Content-Type: application/json' \
  -d '{
  "firstName": "Maxime",
  "lastName": "Beugnet",
  "age": 35,
  "address": {
    "number": 123,
    "street": "avenue des Champs-Elysées",
    "postcode": "75000",
    "city": "Paris",
    "country": "France"
  },
  "insurance": true,
  "cars": [
    {
      "brand": "Peugeot",
      "model": "3008",
      "maxSpeedKmH": 280
    }
  ]
}'

curl -X 'GET' 'http://localhost:8080/api/persons' -H 'accept: */*'

Author

Maxime Beugnet

• [email protected]
• MaBeuLux88 on GitHub
• MaBeuLux88 in the MongoDB Developer Community forum.