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

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

• 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.

• 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.

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

• 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!

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.

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: */*'

Maxime Beugnet

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