Ydb otel tracing

core/src/main/java/tech/ydb/core/grpc/GrpcRequestSettings.java

@@ -6,6 +6,8 @@
 import java.util.function.BooleanSupplier;
 import java.util.function.Consumer;
 
+import javax.annotation.Nullable;
+
 import io.grpc.Metadata;
 
 import tech.ydb.core.impl.call.GrpcFlows;

core/src/main/java/tech/ydb/core/grpc/GrpcTransport.java

@@ -12,6 +12,8 @@
 import io.grpc.MethodDescriptor;
 
 import tech.ydb.core.Result;
+import tech.ydb.core.metrics.NoopMeter;
+import tech.ydb.core.metrics.Meter;
 import tech.ydb.core.tracing.NoopTracer;
 import tech.ydb.core.tracing.Tracer;
 import tech.ydb.core.utils.URITools;
@@ -46,6 +48,14 @@ default Tracer getTracer() {
         return NoopTracer.getInstance();
     }
 
+    default Meter getMeter() {
+        return NoopMeter.INSTANCE;
+    }
+
+    default Meter getMeter() {
+        return NoopMeter.INSTANCE;
+    }
+
     @Override
     void close();
 

core/src/main/java/tech/ydb/core/grpc/GrpcTransportBuilder.java

@@ -26,6 +26,8 @@
 import tech.ydb.core.impl.auth.GrpcAuthRpc;
 import tech.ydb.core.impl.pool.ChannelFactoryLoader;
 import tech.ydb.core.impl.pool.ManagedChannelFactory;
+import tech.ydb.core.metrics.NoopMeter;
+import tech.ydb.core.metrics.Meter;
 import tech.ydb.core.tracing.NoopTracer;
 import tech.ydb.core.tracing.Tracer;
 import tech.ydb.core.utils.Version;
@@ -87,6 +89,7 @@ public enum InitMode {
     private GrpcCompression compression = GrpcCompression.NO_COMPRESSION;
     private InitMode initMode = InitMode.SYNC;
     private Tracer tracer = NoopTracer.getInstance();
+    private Meter meter = NoopMeter.getInstance();
 
     /**
      * can cause leaks https://github.com/grpc/grpc-java/issues/9340
@@ -195,6 +198,10 @@ public Tracer getTracer() {
         return tracer;
     }
 
+    public Meter getMeter() {
+        return meter;
+    }
+
     public ManagedChannelFactory getManagedChannelFactory() {
         if (channelFactoryBuilder == null) {
             channelFactoryBuilder = ChannelFactoryLoader.load();
@@ -423,6 +430,11 @@ public GrpcTransportBuilder withTracer(Tracer tracer) {
         return this;
     }
 
+    public GrpcTransportBuilder withMeter(Meter meter) {
+        this.meter = Objects.requireNonNull(meter, "meter is null");
+        return this;
+    }
+
     /**
      * use {@link GrpcTransportBuilder#withGrpcRetry(boolean) } instead
      * @return this

core/src/main/java/tech/ydb/core/impl/YdbTransportImpl.java

@@ -21,6 +21,7 @@
 import tech.ydb.core.impl.pool.GrpcChannel;
 import tech.ydb.core.impl.pool.GrpcChannelPool;
 import tech.ydb.core.impl.pool.ManagedChannelFactory;
+import tech.ydb.core.metrics.Meter;
 import tech.ydb.core.tracing.Tracer;
 
 /**
@@ -37,6 +38,7 @@ public class YdbTransportImpl extends BaseGrpcTransport {
     private final GrpcChannelPool channelPool;
     private final YdbDiscovery discovery;
     private final Tracer tracer;
+    private final Meter meter;
 
     public YdbTransportImpl(GrpcTransportBuilder builder) {
         super(builder);
@@ -45,6 +47,7 @@ public YdbTransportImpl(GrpcTransportBuilder builder) {
 
         this.database = Strings.nullToEmpty(builder.getDatabase());
         this.tracer = builder.getTracer();
+        this.meter = builder.getMeter();
 
         logger.info("Create YDB transport with endpoint {} and {}", serverEndpoint, balancingSettings);
 
@@ -124,6 +127,11 @@ public Tracer getTracer() {
         return tracer;
     }
 
+    @Override
+    public Meter getMeter() {
+        return meter;
+    }
+
     @Override
     public AuthCallOptions getAuthCallOptions() {
         return callOptions;

core/src/main/java/tech/ydb/core/metrics/Meter.java

@@ -0,0 +1,9 @@
+package tech.ydb.core.metrics;
+
+import tech.ydb.core.Status;
+
+public interface Meter {
+    void recordOperation(String name, long durationNanos, Status status);
+    void registerSessionPool(String poolName, SessionPoolObserver observer);
+    void recordSessionCreateTime(String poolName, long durationNanos);
+}

core/src/main/java/tech/ydb/core/metrics/NoopMeter.java

@@ -0,0 +1,30 @@
+package tech.ydb.core.metrics;
+
+import tech.ydb.core.Status;
+
+public final class NoopMeter implements Meter {
+    public static final NoopMeter INSTANCE = new NoopMeter();
+
+    private NoopMeter() {
+        // No operations.
+    }
+
+    public static NoopMeter getInstance() {
+        return INSTANCE;
+    }
+
+    @Override
+    public void recordOperation(String name, long durationNanos, Status status) {
+
+    }
+
+    @Override
+    public void registerSessionPool(String poolName, SessionPoolObserver observer) {
+
+    }
+
+    @Override
+    public void recordSessionCreateTime(String poolName, long durationNanos) {
+
+    }
+}

core/src/main/java/tech/ydb/core/metrics/SessionPoolObserver.java

@@ -0,0 +1,7 @@
+package tech.ydb.core.metrics;
+
+public interface SessionPoolObserver {
+    int getIdleCount();
+    int getUsedCount();
+    int getPendingCount();
+}

core/src/main/java/tech/ydb/core/tracing/Span.java

@@ -1,127 +1,45 @@
 package tech.ydb.core.tracing;
 
-import java.util.concurrent.CompletableFuture;
-
 import javax.annotation.Nullable;
 
-import io.grpc.ExperimentalApi;
-
-import tech.ydb.core.Result;
 import tech.ydb.core.Status;
-import tech.ydb.core.utils.FutureTools;
 
 /**
  * A span represents a timed operation.
  */
-@ExperimentalApi("YDB Tracer is experimental and API may change without notice")
 public interface Span {
-    Span NOOP = new Span() {
-    };
 
-    /**
-     * Returns W3C traceparent value for request propagation.
-     *
-     * <p>For {@link #NOOP} this returns an empty string. Check {@link #isValid()} to decide whether
-     * trace headers should be sent to server.
-     *
-     * @return traceparent value
-     */
-    default String getId() {
-        return "";
-    }
+    String getId();
 
     /**
-     * Indicates whether this span carries a real tracing context.
-     *
-     * @return true for real spans, false for noop span
-     */
-    default boolean isValid() {
-        return false;
-    }
-
-    /**
-     * Sets a string attribute on the span.
+     * Sets a string attribute on the span (ignored by Noop implementation).
      *
      * @param key attribute key
      * @param value attribute value, may be null
      */
-    default void setAttribute(String key, @Nullable String value) {
-    }
+    void setAttribute(String key, @Nullable String value);
 
     /**
-     * Sets a long attribute on the span.
+     * Sets a long attribute on the span (ignored by Noop implementation).
      *
      * @param key attribute key
      * @param value attribute value
      */
-    default void setAttribute(String key, long value) {
-    }
+    void setAttribute(String key, long value);
 
     /**
-     * Sets span status (success or error) with human-readable message.
+     * Sets span status to error with human-readable message.
      *
-     * @param status operation status used to map span attributes
-     * @param error operation exception used to map span attributes
+     * @param status operation status used to map error attributes
      */
-    default void setStatus(@Nullable Status status, @Nullable Throwable error) {
-    }
+    void setError(Status status);
 
     /**
-     * Makes this span current in the active execution context.
+     * Sets span status to error from exception.
      *
-     * @return closeable scope handle
+     * @param error exception used to map error attributes
      */
-    default Scope makeCurrent() {
-        return () -> {
-        };
-    }
+    void setError(Throwable error);
 
-    /**
-     * Restores context captured when this span was created.
-     *
-     * <p>The returned scope must be closed, usually via try-with-resources.
-     *
-     * @return closeable scope handle for restored context
-     */
-    default Scope restoreContext() {
-        return () -> {
-        };
-    }
-
-    /**
-     * Ends (finishes) this span.
-     */
-    default void end() {
-    }
-
-    /**
-     * Subscribes to a {@link Status} future: when it completes, sets status/error and ends the span.
-     * For non-valid spans returns the future as-is without subscribing.
-     *
-     * @param span the span to finalize
-     * @param future the future to observe
-     * @return the same future (for chaining)
-     */
-    static CompletableFuture<Status> endOnStatus(Span span, CompletableFuture<Status> future) {
-        return span.isValid() ? future.whenComplete((status, th) -> {
-            span.setStatus(status, FutureTools.unwrapCompletionException(th));
-            span.end();
-        }) : future;
-    }
-
-    /**
-     * Subscribes to a {@link Result} future: when it completes, sets status/error and ends the span.
-     * For non-valid spans returns the future as-is without subscribing.
-     *
-     * @param <T> result value type
-     * @param span the span to finalize
-     * @param future the future to observe
-     * @return the same future (for chaining)
-     */
-    static <T> CompletableFuture<Result<T>> endOnResult(Span span, CompletableFuture<Result<T>> future) {
-        return span.isValid() ? future.whenComplete((result, th) -> {
-            span.setStatus(result != null ? result.getStatus() : null, FutureTools.unwrapCompletionException(th));
-            span.end();
-        }) : future;
-    }
+    void end();
 }

core/src/main/java/tech/ydb/core/tracing/SpanFinalizer.java

@@ -0,0 +1,52 @@
+package tech.ydb.core.tracing;
+
+import java.util.function.BiConsumer;
+
+import tech.ydb.core.Status;
+import tech.ydb.core.utils.FutureTools;
+
+/**
+ * Shared helpers to finish spans for status/exception outcomes.
+ */
+public final class SpanFinalizer {
+    private SpanFinalizer() {
+    }
+
+    public static void finishByStatus(Span span, Status status) {
+        if (span == null) {
+            return;
+        }
+
+        if (status != null && !status.isSuccess()) {
+            span.setError(status);
+        }
+
+        span.end();
+    }
+
+    public static void finishByError(Span span, Throwable error) {
+        if (span == null) {
+            return;
+        }
+
+        if (error != null) {
+            span.setError(FutureTools.unwrapCompletionException(error));
+        }
+
+        span.end();
+    }
+
+    public static BiConsumer<Status, Throwable> whenComplete(Span span) {
+        return (status, error) -> {
+            if (span == null) {
+                return;
+            }
+
+            if (error != null) {
+                finishByError(span, error);
+                return;
+            }
+            finishByStatus(span, status);
+        };
+    }
+}