Replaced BucketProvider.

src/main/java/dev/rilling/musicbrainzenricher/api/LoggingBucketListener.java

@@ -16,12 +16,12 @@ public LoggingBucketListener(String bucketName) {
 
 	@Override
 	public void onConsumed(long tokens) {
-		LOGGER.trace("Consumed {} tokens from bucket '{}'.", tokens, bucketName);
+		LOGGER.trace("Consumed {} token(s) from bucket '{}'.", tokens, bucketName);
 	}
 
 	@Override
 	public void onRejected(long tokens) {
-		LOGGER.trace("Rejected consumption of {} tokens from bucket '{}'.", tokens, bucketName);
+		LOGGER.trace("Rejected consumption of {} token(s) from bucket '{}'.", tokens, bucketName);
 	}
 
 	@Override

src/main/java/dev/rilling/musicbrainzenricher/api/discogs/DiscogsApiConfiguration.java

@@ -0,0 +1,28 @@
+package dev.rilling.musicbrainzenricher.api.discogs;
+
+import dev.rilling.musicbrainzenricher.api.LoggingBucketListener;
+import io.github.bucket4j.Bandwidth;
+import io.github.bucket4j.Bucket;
+import net.jcip.annotations.ThreadSafe;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.core.env.Environment;
+
+import java.time.Duration;
+
+@Configuration
+@ThreadSafe
+class DiscogsApiConfiguration {
+
+	@Bean("discogsBucket")
+	Bucket discogsBucket(Environment environment) {
+		boolean authenticated = environment.containsProperty("musicbrainz-enricher.discogs.token");
+
+		// See https://www.discogs.com/developers/#page:home,header:home-rate-limiting,
+		// further slowed down to adapt for network fluctuations.
+		int capacity = authenticated ? 60 : 25;
+		Bandwidth bandwidth = Bandwidth.simple(capacity, Duration.ofSeconds(90));
+
+		return Bucket.builder().addLimit(bandwidth).build().toListenable(new LoggingBucketListener("discogs"));
+	}
+}

src/main/java/dev/rilling/musicbrainzenricher/api/discogs/DiscogsQueryService.java

@@ -1,9 +1,10 @@
 package dev.rilling.musicbrainzenricher.api.discogs;
 
-import dev.rilling.musicbrainzenricher.api.BucketService;
+import io.github.bucket4j.Bucket;
 import net.jcip.annotations.ThreadSafe;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.core.env.Environment;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.MediaType;
@@ -21,22 +22,19 @@ public class DiscogsQueryService {
 
 	private static final Logger LOGGER = LoggerFactory.getLogger(DiscogsQueryService.class);
 
-	private final DiscogsBucketProvider discogsBucketProvider;
-	private final BucketService bucketService;
+	private final Bucket bucket;
 	private final RestClient restClient;
 
 	DiscogsQueryService(Environment environment,
-						DiscogsBucketProvider discogsBucketProvider,
-						BucketService bucketService) {
-		this.discogsBucketProvider = discogsBucketProvider;
-		this.bucketService = bucketService;
+						@Qualifier("discogsBucket") Bucket bucket) {
+		this.bucket = bucket;
 
 		restClient = createRestClient(environment);
 	}
 
 
 	public Optional<DiscogsRelease> lookUpRelease( final String id) {
-		bucketService.consumeSingleBlocking(discogsBucketProvider.getBucket());
+		bucket.asBlocking().consumeUninterruptibly(1);
 
 		try {
 			return Optional.ofNullable(restClient.get().uri("/releases/{id}", Map.of("id", id)).accept().retrieve().body(DiscogsRelease.class));
@@ -48,7 +46,7 @@ public Optional<DiscogsRelease> lookUpRelease( final String id) {
 
 
 	public Optional<DiscogsMaster> lookUpMaster( final String id) {
-		bucketService.consumeSingleBlocking(discogsBucketProvider.getBucket());
+		bucket.asBlocking().consumeUninterruptibly(1);
 
 		try {
 			return Optional.ofNullable(restClient.get().uri("/masters/{id}", Map.of("id", id)).retrieve().body(DiscogsMaster.class));

src/main/java/dev/rilling/musicbrainzenricher/api/spotify/SpotifyApiConfiguration.java

@@ -0,0 +1,24 @@
+package dev.rilling.musicbrainzenricher.api.spotify;
+
+import dev.rilling.musicbrainzenricher.api.LoggingBucketListener;
+import io.github.bucket4j.Bandwidth;
+import io.github.bucket4j.Bucket;
+import net.jcip.annotations.ThreadSafe;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+import java.time.Duration;
+
+@Configuration
+@ThreadSafe
+class SpotifyApiConfiguration {
+
+	@Bean("spotifyBucket")
+	Bucket spotifyBucket() {
+		// https://developer.spotify.com/documentation/web-api/guides/rate-limits/
+		// Spotify itself does not disclose an exact rate, this is only a guess to avoid running into it.
+		Bandwidth bandwidth = Bandwidth.simple(10, Duration.ofMinutes(1));
+
+		return Bucket.builder().addLimit(bandwidth).build().toListenable(new LoggingBucketListener("spotify"));
+	}
+}

src/main/java/dev/rilling/musicbrainzenricher/api/spotify/SpotifyQueryService.java

@@ -1,12 +1,13 @@
 package dev.rilling.musicbrainzenricher.api.spotify;
 
-import dev.rilling.musicbrainzenricher.api.BucketService;
+import io.github.bucket4j.Bucket;
 import jakarta.annotation.Nullable;
 import net.jcip.annotations.GuardedBy;
 import net.jcip.annotations.ThreadSafe;
 import org.apache.hc.core5.http.ParseException;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.core.env.Environment;
 import org.springframework.stereotype.Service;
 import se.michaelthelin.spotify.SpotifyApi;
@@ -27,8 +28,7 @@ public class SpotifyQueryService {
 
 	private static final Logger LOGGER = LoggerFactory.getLogger(SpotifyQueryService.class);
 
-	private final SpotifyBucketProvider spotifyBucketProvider;
-	private final BucketService bucketService;
+	private final Bucket bucket;
 
 	// May be null if no credentials exist.
 	// Note that getAuthorizedApiClient() should be used for access.
@@ -42,10 +42,8 @@ public class SpotifyQueryService {
 	private final Object reAuthLock = new Object();
 
 	SpotifyQueryService(Environment environment,
-						SpotifyBucketProvider spotifyBucketProvider,
-						BucketService bucketService) {
-		this.spotifyBucketProvider = spotifyBucketProvider;
-		this.bucketService = bucketService;
+						@Qualifier("spotifyBucket") Bucket bucket) {
+		this.bucket = bucket;
 
 		apiClient = createApiClient(environment);
 	}
@@ -57,7 +55,7 @@ public Optional<Album> lookUpRelease(final String id) {
 			return Optional.empty();
 		}
 
-		bucketService.consumeSingleBlocking(spotifyBucketProvider.getBucket());
+		bucket.asBlocking().consumeUninterruptibly(1);
 
 		try {
 			GetAlbumRequest request = getAuthorizedApiClient().getAlbum(id).build();