content: /*
   * Copyright The OpenTelemetry Authors
   * SPDX-License-Identifier: Apache-2.0
   */
  
  package io.opentelemetry.javaagent.instrumentation.lettuce.v5_0;
  
  import static io.opentelemetry.javaagent.bootstrap.Java8BytecodeBridge.currentContext;
  import static io.opentelemetry.javaagent.instrumentation.lettuce.v5_0.LettuceInstrumentationUtil.expectsResponse;
  import static io.opentelemetry.javaagent.instrumentation.lettuce.v5_0.LettuceSingletons.instrumenter;
  import static net.bytebuddy.matcher.ElementMatchers.isMethod;
  import static net.bytebuddy.matcher.ElementMatchers.named;
  import static net.bytebuddy.matcher.ElementMatchers.takesArgument;
  
  import io.lettuce.core.protocol.AsyncCommand;
  import io.lettuce.core.protocol.RedisCommand;
  import io.opentelemetry.context.Context;
  import io.opentelemetry.context.Scope;
  import io.opentelemetry.javaagent.extension.instrumentation.TypeInstrumentation;
  import io.opentelemetry.javaagent.extension.instrumentation.TypeTransformer;
  import net.bytebuddy.asm.Advice;
  import net.bytebuddy.description.type.TypeDescription;
  import net.bytebuddy.matcher.ElementMatcher;
  
  public class LettuceAsyncCommandsInstrumentation implements TypeInstrumentation {
  
    @Override
    public ElementMatcher<TypeDescription> typeMatcher() {
      return named("io.lettuce.core.AbstractRedisAsyncCommands");
    }
  
    @Override
    public void transform(TypeTransformer transformer) {
      transformer.applyAdviceToMethod(
          isMethod()
              .and(named("dispatch"))
              .and(takesArgument(0, named("io.lettuce.core.protocol.RedisCommand"))),
          LettuceAsyncCommandsInstrumentation.class.getName() + "$DispatchAdvice");
    }
  
    @SuppressWarnings("unused")
    public static class DispatchAdvice {
  
      @Advice.OnMethodEnter(suppress = Throwable.class)
      public static void onEnter(
          @Advice.Argument(0) RedisCommand<?, ?, ?> command,
          @Advice.Local("otelContext") Context context,
          @Advice.Local("otelScope") Scope scope) {
  
        Context parentContext = currentContext();
        context = instrumenter().start(parentContext, command);
        // remember the context that called dispatch, it is used in LettuceAsyncCommandInstrumentation
        context = context.with(LettuceSingletons.COMMAND_CONTEXT_KEY, parentContext);
        scope = context.makeCurrent();
      }
  
      @Advice.OnMethodExit(onThrowable = Throwable.class, suppress = Throwable.class)
      public static void stopSpan(
          @Advice.Argument(0) RedisCommand<?, ?, ?> command,
          @Advice.Thrown Throwable throwable,
          @Advice.Return AsyncCommand<?, ?, ?> asyncCommand,
          @Advice.Local("otelContext") Context context,
          @Advice.Local("otelScope") Scope scope) {
        scope.close();
  
        if (throwable != null) {
          instrumenter().end(context, command, null, throwable);
          return;
        }
  
        // close spans on error or normal completion
        if (expectsResponse(command)) {
          asyncCommand.handleAsync(new EndCommandAsyncBiFunction<>(context, command));
        } else {
          instrumenter().end(context, command, null, null);
        }
      }
    }
  }
  