server/blob/blob-api/src/main/java/org/apache/james/blob/api/ObjectStorageHealthCheck.java

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 * to you under the Apache License, Version 2.0 (the            *
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package org.apache.james.blob.api;

import java.time.Duration;

import javax.inject.Inject;

import org.apache.james.core.healthcheck.ComponentName;
import org.apache.james.core.healthcheck.HealthCheck;
import org.apache.james.core.healthcheck.Result;

import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;

public class ObjectStorageHealthCheck implements HealthCheck {

    private static final Integer HEALTH_CHECK_TIMEOUT = 10;

    private static final ComponentName COMPONENT_NAME = new ComponentName("ObjectStorage");

    private final BlobStoreDAO blobStoreDAO;

    @Inject
    public ObjectStorageHealthCheck(BlobStoreDAO blobStoreDAO) {
        this.blobStoreDAO = blobStoreDAO;
    }

    @Override
    public ComponentName componentName() {
        return COMPONENT_NAME;
    }

    @Override
    public Mono<Result> check() {
        return Flux.from(blobStoreDAO.listBuckets())
            .timeout(Duration.ofSeconds(HEALTH_CHECK_TIMEOUT))
            .next()
            .thenReturn(Result.healthy(COMPONENT_NAME))
            .onErrorResume(e -> Mono.just(Result.unhealthy(COMPONENT_NAME, "Error checking ObjectSotrage", e)));
    }
}