Make mongoClientNames Configuration-Based in MongoClientProcessor

[nitinty]

Hi Team,

Would it be possible to make the mongoClientNames code configuration-based instead of relying on annotation scanning (@MongoClientName)? This would allow us to retrieve all configured tenant MongoClient instances via Arc.container() when needed (e.g., for creating indexes at startup) rather than injecting each client separately into our class.

Additionally, the current approach requires developers to modify the code whenever a new tenant needs to be onboarded. A configuration-based approach would make this process more dynamic and flexible.

Extension Code 

    @BuildStep
    public void mongoClientNames(CombinedIndexBuildItem indexBuildItem,
            BuildProducer<MongoClientNameBuildItem> mongoClientName) {
        Set<String> values = new HashSet<>();
        IndexView indexView = indexBuildItem.getIndex();
        addMongoClientNameValues(MONGO_CLIENT_ANNOTATION, indexView, values);
        for (String value : values) {
            mongoClientName.produce(new MongoClientNameBuildItem(value));
        }
    }

    private void addMongoClientNameValues(DotName annotationName, IndexView indexView, Set<String> values) {
        Collection<AnnotationInstance> mongoClientAnnotations = indexView.getAnnotations(annotationName);
        for (AnnotationInstance annotation : mongoClientAnnotations) {
            values.add(annotation.value().asString());
        }
    }

I tried the following approach, but the issue is that the configuration becomes mandatory at build time, which I want to avoid to keep the solution dynamic.
Can anyone suggest an approach that eliminates this config binding at build time and allows it to be picked up at runtime ?

        @BuildStep
    public void mongoClientNames(CombinedIndexBuildItem indexBuildItem,
                                 BuildProducer<MongoClientNameBuildItem> mongoClientName) {

        Set<String> values = new HashSet<>();
        Optional<List<String>> configuredTenants = ConfigProvider.getConfig().getOptionalValues("multitenant.mongodb.supported-tenants",String.class);
        configuredTenants.ifPresent(values::addAll);
        for (String value : values) {
            mongoClientName.produce(new MongoClientNameBuildItem(value));
        }
    }

Thanks in advance !!!

[quarkus-bot[bot]]

/cc @loicmathieu (mongodb), @radcortez (config)

[nitinty]

@geoand @FroMage
Could you please assist with this or tag someone who can ??

[geoand]

The Mongo client extension relies on the fact that the clients need to be known at build time. This is the same situation as other clients like JDBC, Redis etc.

[nitinty]

@geoand

Thanks for the response! I understand that Mongo clients need to be known at build time, similar to JDBC and Redis. My main concern is whether there’s a way to determine the required clients dynamically via configuration instead of relying on annotation scanning.

For example, instead of scanning for @MongoClientName, could we use a Quarkus configuration property (e.g., multitenant.mongodb.supported-tenants) to define client names ?

Would it be possible to achieve this while still satisfying the build-time requirement of knowing the clients ? Or is there a recommended alternative to achieve this flexibility ?

[geoand]

You can try generating MongoClientName like you showed in your sample extension, that will probably work.

[nitinty]

I actually tried the approach of generating MongoClientNameBuildItem from the config (multitenant.mongodb.supported-tenants), and it works perfectly.

However, the issue is that this configuration now becomes mandatory at build time, which I want to avoid. Ideally, I’d like to make this config optional, allowing it to be defined dynamically at runtime instead of being required at build time. And based on that It could generate MongoClientName

        @BuildStep
    public void mongoClientNames(CombinedIndexBuildItem indexBuildItem,
                                 BuildProducer<MongoClientNameBuildItem> mongoClientName) {

        Set<String> values = new HashSet<>();
        Optional<List<String>> configuredTenants = ConfigProvider.getConfig().getOptionalValues("multitenant.mongodb.supported-tenants",String.class);
        configuredTenants.ifPresent(values::addAll);
        for (String value : values) {
            mongoClientName.produce(new MongoClientNameBuildItem(value));
        }
    }

[geoand]

Unfortunately that isn't supported currently.