add lettuce db client metrics

Author: zeitlinger

instrumentation/lettuce/lettuce-5.1/library/src/main/java/io/opentelemetry/instrumentation/lettuce/v5_1/OpenTelemetryTracing.java

@@ -196,7 +196,7 @@ private static class OpenTelemetrySpan extends Tracer.Span {
     @Nullable private Throwable error;
     @Nullable private Span span;
     private long spanStartTime;
-    private final AttributesBuilder attributesBuilder = Attributes.builder();
+    private final AttributesBuilder attributesBuilder = Attributes.builder().put(DB_SYSTEM, REDIS);
     @Nullable private List<String> argsList;
     @Nullable private String argsString;
 
@@ -243,7 +243,7 @@ private void fillEndpoint(OpenTelemetryEndpoint endpoint) {
       } else {
         spanBuilder.setAllAttributes(attributes);
       }
-      attributesBuilder.putAll(attributes);
+      this.attributesBuilder.putAll(attributes);
     }
 
     // Added and called in 6.0+
@@ -381,8 +381,10 @@ private void finish(Span span, long startTime) {
             sanitizer.sanitize(name, argsList != null ? argsList : splitArgs(argsString));
         if (SemconvStability.emitStableDatabaseSemconv()) {
           span.setAttribute(DB_QUERY_TEXT, statement);
-          Context c = metrics.onStart(Context.current(), Attributes.empty(), startTime);
-          metrics.onEnd(c, attributesBuilder.build(), System.nanoTime());
+          metrics.onEnd(
+              metrics.onStart(Context.current(), Attributes.empty(), startTime),
+              attributesBuilder.build(),
+              System.nanoTime());
         }
         if (SemconvStability.emitOldDatabaseSemconv()) {
           span.setAttribute(DB_STATEMENT, statement);

instrumentation/lettuce/lettuce-5.1/testing/src/main/java/io/opentelemetry/instrumentation/lettuce/v5_1/AbstractLettuceSyncClientTest.java

@@ -14,9 +14,6 @@
 import static io.opentelemetry.semconv.NetworkAttributes.NETWORK_TYPE;
 import static io.opentelemetry.semconv.ServerAttributes.SERVER_ADDRESS;
 import static io.opentelemetry.semconv.ServerAttributes.SERVER_PORT;
-import static io.opentelemetry.semconv.incubating.DbIncubatingAttributes.DB_COLLECTION_NAME;
-import static io.opentelemetry.semconv.incubating.DbIncubatingAttributes.DB_NAMESPACE;
-import static io.opentelemetry.semconv.incubating.DbIncubatingAttributes.DB_OPERATION_NAME;
 import static io.opentelemetry.semconv.incubating.DbIncubatingAttributes.DB_STATEMENT;
 import static io.opentelemetry.semconv.incubating.DbIncubatingAttributes.DB_SYSTEM;
 import static java.nio.charset.StandardCharsets.UTF_8;
@@ -144,9 +141,10 @@ void testSetCommand() {
         testing(),
         "io.opentelemetry.lettuce-5.1",
         DB_SYSTEM,
-        DB_COLLECTION_NAME,
-        DB_NAMESPACE,
-        DB_OPERATION_NAME);
+        SERVER_ADDRESS,
+        SERVER_PORT,
+        NETWORK_PEER_ADDRESS,
+        NETWORK_PEER_PORT);
   }
 
   @Test

testing-common/src/main/java/io/opentelemetry/instrumentation/testing/junit/db/DbClientMetricsTestUtil.java

@@ -19,6 +19,8 @@ public static void assertDurationMetric(
       InstrumentationExtension testing,
       String instrumentationName,
       AttributeKey<?>... expectedKeys) {
+    // db.system is required - see https://opentelemetry.io/docs/specs/semconv/database/database-metrics/#metric-dbclientoperationduration
+    assertThat(expectedKeys).extracting(AttributeKey::getKey).contains("db.system");
     if (!emitStableDatabaseSemconv()) {
       return;
     }