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BE: fix prometheus endpoint and warn on label duplicates #1546

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Merged
merged 2 commits into from
Dec 1, 2025
Merged

BE: fix prometheus endpoint and warn on label duplicates #1546

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4acfe54
BE: fix prometheus endpoint and warn on label duplicates
germanosin Dec 1, 2025
580d386
BE: fix prometheus endpoint and warn on label duplicates
germanosin Dec 1, 2025
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2 changes: 1 addition & 1 deletion api/src/main/java/io/kafbat/ui/service/metrics/prometheus/PrometheusMetricsExposer.java
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Expand Up @@ -30,7 +30,7 @@ public final class PrometheusMetricsExposer {

static {
PROMETHEUS_EXPOSE_ENDPOINT_HEADERS = new HttpHeaders();
PROMETHEUS_EXPOSE_ENDPOINT_HEADERS.set(CONTENT_TYPE, OpenMetricsTextFormatWriter.CONTENT_TYPE);
PROMETHEUS_EXPOSE_ENDPOINT_HEADERS.set(CONTENT_TYPE, PrometheusTextFormatWriter.CONTENT_TYPE);
}

private PrometheusMetricsExposer() {
Expand Down
9 changes: 8 additions & 1 deletion api/src/main/java/io/kafbat/ui/util/MetricsUtils.java
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Expand Up @@ -17,7 +17,9 @@
import java.util.Collection;
import java.util.List;
import java.util.stream.Stream;
import lombok.extern.slf4j.Slf4j;

@Slf4j
public final class MetricsUtils {

private MetricsUtils() {
Expand Down Expand Up @@ -109,6 +111,11 @@ public static MetricSnapshot concatDataPoints(MetricSnapshot d1, MetricSnapshot
}

private static Labels extendLabels(Labels labels, String name, String value) {
return labels.add(name, value);
if (!labels.contains(name)) {
return labels.add(name, value);
} else {
log.warn("Label {} already exists with value {} not updated to {}, skipping", name, labels.get(name), value);
return labels;
}
}
}
10 changes: 10 additions & 0 deletions api/src/test/java/io/kafbat/ui/AbstractIntegrationTest.java
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Expand Up @@ -39,12 +39,19 @@ public abstract class AbstractIntegrationTest {
public static final String SECOND_LOCAL = "secondLocal";

private static final String CONFLUENT_PLATFORM_VERSION = "7.8.0";
private static final int JMX_PORT = 5555;

public static final ConfluentKafkaContainer kafkaOriginal = new ConfluentKafkaContainer(
DockerImageName.parse("confluentinc/cp-kafka").withTag(CONFLUENT_PLATFORM_VERSION));

public static final ConfluentKafkaContainer kafka = kafkaOriginal
.withListener("0.0.0.0:9095", () -> kafkaOriginal.getNetworkAliases().getFirst() + ":9095")
.withEnv("KAFKA_JMX_PORT", String.valueOf(JMX_PORT))
.withEnv("KAFKA_OPTS",
"-Dcom.sun.management.jmxremote "
+ "-Dcom.sun.management.jmxremote.authenticate=false "
+ "-Dcom.sun.management.jmxremote.ssl=false "
+ "-Dcom.sun.management.jmxremote.local.only=false")
.withNetwork(Network.SHARED);

public static final SchemaRegistryContainer schemaRegistry =
Expand All @@ -67,6 +74,7 @@ public abstract class AbstractIntegrationTest {
public static Path tmpDir;

static {
kafka.addExposedPort(JMX_PORT);
kafka.start();
schemaRegistry.start();
kafkaConnect.start();
Expand Down Expand Up @@ -111,6 +119,8 @@ public void initialize(@NotNull ConfigurableApplicationContext context) {
IsolationLevel.READ_COMMITTED.toString());
System.setProperty("kafka.clusters.0.producerProperties.request.timeout.ms", "45000");
System.setProperty("kafka.clusters.0.producerProperties.max.block.ms", "80000");
System.setProperty("kafka.clusters.0.metrics.prometheusExpose", "true");
System.setProperty("kafka.clusters.0.metrics.port", kafka.getMappedPort(JMX_PORT).toString());

System.setProperty("kafka.clusters.1.name", SECOND_LOCAL);
System.setProperty("kafka.clusters.1.readOnly", "true");
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32 changes: 32 additions & 0 deletions api/src/test/java/io/kafbat/ui/controller/PrometheusExposeControllerTest.java
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@@ -0,0 +1,32 @@
package io.kafbat.ui.controller;

import static org.assertj.core.api.Assertions.assertThat;

import io.kafbat.ui.AbstractIntegrationTest;
import io.kafbat.ui.service.ClustersStatisticsScheduler;
import io.prometheus.metrics.expositionformats.PrometheusTextFormatWriter;
import java.io.IOException;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.web.reactive.server.WebTestClient;

class PrometheusExposeControllerTest extends AbstractIntegrationTest {
@Autowired
private WebTestClient webTestClient;

@Autowired
private ClustersStatisticsScheduler scheduler;

@Test
void testGetMetrics() throws IOException {

scheduler.updateStatistics();

webTestClient
.get()
.uri("/metrics")
.exchange()
.expectStatus().isOk()
.expectHeader().contentType(PrometheusTextFormatWriter.CONTENT_TYPE);
}
}
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