Use bom and pass service and realm to token refresh

pom.xml

@@ -103,6 +103,13 @@
 
   <dependencyManagement>
     <dependencies>
+      <dependency>
+        <groupId>io.micrometer</groupId>
+        <artifactId>micrometer-bom</artifactId>
+        <version>${micrometer.version}</version>
+        <type>pom</type>
+        <scope>import</scope>
+      </dependency>
       <dependency>
         <groupId>org.junit</groupId>
         <artifactId>junit-bom</artifactId>
@@ -137,11 +144,6 @@
         <artifactId>classgraph</artifactId>
         <version>${classgraph.version}</version>
       </dependency>
-      <dependency>
-        <groupId>io.micrometer</groupId>
-        <artifactId>micrometer-core</artifactId>
-        <version>${micrometer.version}</version>
-      </dependency>
       <dependency>
         <groupId>org.apache.commons</groupId>
         <artifactId>commons-compress</artifactId>

src/main/java/land/oras/auth/HttpClient.java

@@ -20,7 +20,6 @@
 
 package land.oras.auth;
 
-import io.micrometer.core.instrument.Counter;
 import io.micrometer.core.instrument.MeterRegistry;
 import io.micrometer.core.instrument.simple.SimpleMeterRegistry;
 import java.io.FileNotFoundException;
@@ -68,11 +67,6 @@ public final class HttpClient {
      */
     private static final Logger LOG = LoggerFactory.getLogger(HttpClient.class);
 
-    /**
-     * Metric name for token refresh counter
-     */
-    public static final String TOKEN_REFRESH_METRIC = "oras.auth.token.refresh";
-
     /**
      * The pattern for the WWW-Authenticate header value
      */
@@ -103,12 +97,6 @@ public final class HttpClient {
      * The meter registry for metrics
      */
     private MeterRegistry meterRegistry;
-
-    /**
-     * Counter for token refreshes
-     */
-    private Counter tokenRefreshCounter;
-
     /**
      * Hidden constructor
      */
@@ -157,9 +145,6 @@ private void setTlsVerify(boolean skipTlsVerify) {
      */
     public HttpClient build() {
         this.client = this.builder.build();
-        this.tokenRefreshCounter = Counter.builder(TOKEN_REFRESH_METRIC)
-                .description("Number of token refreshes performed against the registry")
-                .register(meterRegistry);
         return this;
     }
 
@@ -463,7 +448,9 @@ public <T> TokenResponse refreshToken(
         TokenResponse token = JsonUtils.fromJson(responseWrapper.response(), TokenResponse.class)
                 .forService(service);
         TokenCache.put(newScopes, token);
-        tokenRefreshCounter.increment();
+        meterRegistry
+                .counter(Const.METRIC_TOKEN_REFRESH, Const.METRIC_TAG_SERVICE, service, Const.METRIC_TAG_REALM, realm)
+                .increment();
         return token;
     }
 

src/main/java/land/oras/utils/Const.java

@@ -440,4 +440,19 @@ public static String currentTimestamp() {
      * OCI Chunk Minimum Length header
      */
     public static final String OCI_CHUNK_MIN_LENGTH_HEADER = "OCI-Chunk-Min-Length";
+
+    /**
+     * Metric name for token refresh counter
+     */
+    public static final String METRIC_TOKEN_REFRESH = "land_oras_auth_token_refresh_total";
+
+    /**
+     * Metric name for token refresh duration
+     */
+    public static final String METRIC_TAG_SERVICE = "service";
+
+    /**
+     * Metric name for token refresh duration
+     */
+    public static final String METRIC_TAG_REALM = "realm";
 }

src/test/java/land/oras/DockerIoITCase.java

@@ -22,7 +22,11 @@
 
 import static org.junit.jupiter.api.Assertions.*;
 
+import io.micrometer.core.instrument.Counter;
+import io.micrometer.core.instrument.MeterRegistry;
+import io.micrometer.core.instrument.simple.SimpleMeterRegistry;
 import java.nio.file.Path;
+import land.oras.utils.Const;
 import land.oras.utils.ZotUnsecureContainer;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.io.TempDir;
@@ -106,8 +110,12 @@ void shouldPullOneBlob() {
     void shouldCopyTagToInternalRegistry() {
 
         // Source registry
-        Registry sourceRegistry =
-                Registry.Builder.builder().withParallelism(3).defaults().build();
+        MeterRegistry meterRegistry = new SimpleMeterRegistry();
+        Registry sourceRegistry = Registry.Builder.builder()
+                .withMeterRegistry(meterRegistry)
+                .withParallelism(3)
+                .defaults()
+                .build();
 
         // Copy to this internal registry
         Registry targetRegistry = Registry.Builder.builder()
@@ -122,6 +130,12 @@ void shouldCopyTagToInternalRegistry() {
 
         CopyUtils.copy(sourceRegistry, containerSource, targetRegistry, containerTarget, CopyUtils.CopyOptions.deep());
         assertTrue(targetRegistry.exists(containerTarget));
+
+        assertEquals(
+                1.0,
+                meterRegistry.find(Const.METRIC_TOKEN_REFRESH).counters().stream()
+                        .mapToDouble(Counter::count)
+                        .sum());
     }
 
     @Test

src/test/java/land/oras/RegistryWireMockTest.java

@@ -31,6 +31,8 @@
 import com.github.tomakehurst.wiremock.junit5.WireMockRuntimeInfo;
 import com.github.tomakehurst.wiremock.junit5.WireMockTest;
 import com.github.tomakehurst.wiremock.stubbing.Scenario;
+import io.micrometer.core.instrument.Counter;
+import io.micrometer.core.instrument.simple.SimpleMeterRegistry;
 import java.io.IOException;
 import java.io.InputStream;
 import java.net.URI;
@@ -584,8 +586,7 @@ void shouldRefreshExpiredToken(WireMockRuntimeInfo wmRuntimeInfo) {
                         WireMock.ok().withBody("blob-data").withHeader(Const.DOCKER_CONTENT_DIGEST_HEADER, digest)));
 
         // Insecure registry with a custom meter registry to track metrics
-        io.micrometer.core.instrument.simple.SimpleMeterRegistry meterRegistry =
-                new io.micrometer.core.instrument.simple.SimpleMeterRegistry();
+        SimpleMeterRegistry meterRegistry = new SimpleMeterRegistry();
         Registry registry = Registry.Builder.builder()
                 .withAuthProvider(new BearerTokenProvider()) // Already bearer token
                 .withInsecure(true)
@@ -600,8 +601,21 @@ void shouldRefreshExpiredToken(WireMockRuntimeInfo wmRuntimeInfo) {
         // Verify that exactly one token refresh was performed
         assertEquals(
                 1.0,
-                meterRegistry.counter(HttpClient.TOKEN_REFRESH_METRIC).count(),
+                meterRegistry
+                        .counter(
+                                Const.METRIC_TOKEN_REFRESH,
+                                Const.METRIC_TAG_SERVICE,
+                                "localhost",
+                                Const.METRIC_TAG_REALM,
+                                "http://localhost:%d/token".formatted(wmRuntimeInfo.getHttpPort()))
+                        .count(),
                 "Token refresh counter should be 1 after one token refresh");
+        assertEquals(
+                1.0,
+                meterRegistry.find(Const.METRIC_TOKEN_REFRESH).counters().stream()
+                        .mapToDouble(Counter::count)
+                        .sum());
+        TestUtils.dumpMetrics(meterRegistry);
     }
 
     @Test

src/test/java/land/oras/TestUtils.java

@@ -20,16 +20,38 @@
 
 package land.oras;
 
+import io.micrometer.core.instrument.Meter;
+import io.micrometer.core.instrument.MeterRegistry;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import uk.org.webcompere.systemstubs.environment.EnvironmentVariables;
 
 /**
  * Several tests utils
  */
 public final class TestUtils {
 
+    /**
+     * Logger
+     */
+    private static final Logger LOG = LoggerFactory.getLogger(TestUtils.class);
+
+    /**
+     * Dump current metrics to console for debug purpose
+     * @param meterRegistry the meter registry to dump
+     */
+    public static void dumpMetrics(MeterRegistry meterRegistry) {
+        meterRegistry.getMeters().forEach(meter -> {
+            Meter.Id id = meter.getId();
+            LOG.info("{} {}", id.getName(), id.getTags());
+
+            meter.measure().forEach(ms -> LOG.info("  {}={}", ms.getStatistic(), ms.getValue()));
+        });
+    }
+
     /**
      * Create a registries.conf file in the given home directory with the given content.
      * @param homeDir the home directory where the .config/containers/registries.conf file will be created