Spring Data for Mongo DB does not throw DuplicateKeyException - spring

Question

I try to throw a DuplicateKeyException in a jUnit 5 Test. The unit test saves two objects to a repository with the same productId. productID is declared #Indexed( unique = true ) in the ProductEntity class. My expectation was to receive a DuplicateKeyException.
This is the test class:
package com.exercim.microservices.core.product;
import static org.junit.jupiter.api.Assertions.assertThrows;
import com.exercim.microservices.core.product.persistence.ProductEntity;
import com.exercim.microservices.core.product.persistence.ProductRepository;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.data.mongo.DataMongoTest;
import org.springframework.dao.DuplicateKeyException;
#DataMongoTest
public class ProductRepositoryTest {
#Autowired
ProductRepository repository ;
#Test
public void testDuplicateKeyException() {
ProductEntity e1 = new ProductEntity( 1, "name", 1 ) ;
ProductEntity e2 = new ProductEntity( 1, "name", 1 ) ;
repository.deleteAll() ;
repository.save( e1 ) ;
assertThrows(DuplicateKeyException.class, () -> repository.save( e2 ) ) ;
}
}
This is the ProductEntitiy class:
package com.exercim.microservices.core.product.persistence;
import org.springframework.data.annotation.Id;
import org.springframework.data.annotation.Version;
import org.springframework.data.mongodb.core.index.Indexed;
import org.springframework.data.mongodb.core.mapping.Document;
#Document( collection = "products" )
public class ProductEntity {
#Id
private String id ;
#Version
private Integer version ;
#Indexed( unique = true )
private int productId ;
private String name ;
private Integer weight ;
public ProductEntity() {
}
public ProductEntity( int productId, String name, int weight) {
this.productId = productId;
this.name = name;
this.weight = weight;
}
public String getId() {
return this.id;
}
public void setId(String id) {
this.id = id;
}
public int getVersion() {
return this.version;
}
public void setVersion(int version) {
this.version = version;
}
public int getProductId() {
return this.productId;
}
public void setProductId(int productId) {
this.productId = productId;
}
public String getName() {
return this.name;
}
public void setName(String name) {
this.name = name;
}
public int getWeight() {
return this.weight;
}
public void setWeight(int weight) {
this.weight = weight;
}
}
The repository is an interface which extends PagingAndSortingRepository
This is part of my build.gradle file:
implementation group: 'org.springframework.boot', name: 'spring-boot-starter-data-mongodb'
testImplementation 'de.flapdoodle.embed:de.flapdoodle.embed.mongo'
The test fails with the message:
org.opentest4j.AssertionFailedError: Expected org.springframework.dao.DuplicateKeyException to be thrown, but nothing was thrown.
at org.junit.jupiter.api.AssertThrows.assertThrows(AssertThrows.java:71)
Does anyone have an idea? Thanks in advance!

Answer 1

Thanks Joe!
The problem was, that auto index creation was not enabled. This was my original application.yml file:
spring.data.mongodb:
host: localhost
port: 27017
database: product-db
I added the following line:
auto-index-creation: true
That solved the issue.