GraalVM mongodb-reactive SpringNative: Java Runs Fine but Compiled Executable Can't Connect to MongoDB

Problem Reproduction

The dependency used is:

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-mongodb-reactive</artifactId>
</dependency>

Added MongoConfig:

import com.mongodb.reactivestreams.client.MongoClient;
import com.mongodb.reactivestreams.client.MongoClients;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Profile;
import org.springframework.data.mongodb.config.AbstractReactiveMongoConfiguration;
import org.springframework.data.mongodb.core.ReactiveMongoTemplate;
import org.springframework.data.mongodb.core.convert.MappingMongoConverter;
import org.springframework.data.mongodb.gridfs.ReactiveGridFsTemplate;
import org.springframework.data.mongodb.repository.config.EnableReactiveMongoRepositories;

@Configuration
@EnableReactiveMongoRepositories("run.runnable.xxx.repository")
public class MongoConfig extends AbstractReactiveMongoConfiguration {

    @Value("${spring.data.mongodb.host}")
    String host;

    @Value("${spring.data.mongodb.port}")
    String port;

    @Value("${spring.data.mongodb.username}")
    String username;

    @Value("${spring.data.mongodb.password}")
    String password;

    @Value("${spring.data.mongodb.database}")
    String database;

    @Override
    protected String getDatabaseName() {
        return database;
    }

    @Override
    public MongoClient reactiveMongoClient() {
        String uri =
        return MongoClients.create(uri);
    }

    @Bean
    public ReactiveGridFsTemplate reactiveGridFsTemplate(MappingMongoConverter mappingMongoConverter) {
        return new ReactiveGridFsTemplate(reactiveMongoDbFactory(), mappingMongoConverter, "attachments");
    }

    private MongoClient mongoClient;
    @Autowired
    public void setMongoClient(MongoClient mongoClient) {
        this.mongoClient = mongoClient;
    }

    @Bean
    public ReactiveMongoTemplate reactiveMongoTemplate() {
        return new ReactiveMongoTemplate(mongoClient, getDatabaseName());
    }
}

YAML configuration roughly as follows:

spring:
  data:
    mongodb:
      host: host
      username: username
      password: password
      database: database
      port: 27017

Starting and connecting to the database with the Java version works fine, but after compiling to an executable, it throws an error on startup. The error message is:

Caused by: com.mongodb.MongoCommandException: Command failed with error 18 (AuthenticationFailed): 'Authentication failed.' on server host. The full response is {"ok": 0.0, "errmsg": "Authentication failed.", "code": 18, "codeName": "AuthenticationFailed"}
        at com.mongodb.internal.connection.ProtocolHelper.getCommandFailureException(ProtocolHelper.java:205) ~[na:na]
        at com.mongodb.internal.connection.InternalStreamConnection.lambda$sendCommandMessageAsync$0(InternalStreamConnection.java:539) ~[na:na]
        ... 36 common frames omitted

Solution

After searching online without finding a solution, I guessed someone must have done this combination before. So I searched on GitHub and actually found one. I pulled down their code, updated to the latest SpringBoot version, switched the SpringBoot connection, and what! Theirs actually worked. I checked the difference between their configuration and mine, and found they didn't add any MongoConfig at all - they just wrote the connection URL directly in application.properties.

I made some changes to their code and pushed it back to GitHub. Address: https://github.com/MingGH/spring-native-demo You can pull it down directly and try configuring and starting it.

spring.data.mongodb.uri=mongodb://localhost:27017/blog
logging.level.root=INFO
logging.level.org.springframework.aot=TRACE

So I deleted my MongoConfig and configured in application.yaml:

spring:
  data:
    mongodb:
      uri: mongodb://localhost:27017/blog

Compiled again, and it actually worked... I suspect SpringNative has made compatibility for auto-configuration, correctly injecting parameters, but using the MongoConfig form doesn't work.

Problem Reproduction​

Solution​

Problem Reproduction

Solution