diff --git a/src/main/java/it/tdlight/utils/MonoUtils.java b/src/main/java/it/tdlight/utils/MonoUtils.java
index cfc6b4d..e1c6271 100644
--- a/src/main/java/it/tdlight/utils/MonoUtils.java
+++ b/src/main/java/it/tdlight/utils/MonoUtils.java
@@ -15,6 +15,7 @@ import io.vertx.reactivex.core.streams.Pipe;
 import io.vertx.reactivex.core.streams.ReadStream;
 import io.vertx.reactivex.core.streams.WriteStream;
 import it.tdlight.jni.TdApi;
+import it.tdlight.jni.TdApi.Chat;
 import it.tdlight.jni.TdApi.Object;
 import it.tdlight.tdlibsession.td.TdError;
 import it.tdlight.tdlibsession.td.TdResult;
@@ -29,6 +30,7 @@ import java.util.function.Consumer;
 import java.util.function.Supplier;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
+import org.reactivestreams.Publisher;
 import org.reactivestreams.Subscription;
 import org.warp.commonutils.concurrency.future.CompletableFutureUtils;
 import org.warp.commonutils.log.Logger;
@@ -295,6 +297,10 @@ public class MonoUtils {
 		return Mono.defer(() -> fromEmitResult(sink.tryEmitEmpty()));
 	}
 
+	public static <T> Mono<Void> emitEmpty(One<T> sink) {
+		return Mono.defer(() -> fromEmitResult(sink.tryEmitEmpty()));
+	}
+
 	public static <T> Mono<Void> emitError(Empty<T> sink, Throwable value) {
 		return Mono.defer(() -> fromEmitResult(sink.tryEmitError(value)));
 	}
@@ -435,6 +441,12 @@ public class MonoUtils {
 		return mono.map(Optional::of).defaultIfEmpty(Optional.empty());
 	}
 
+	public static <T> Mono<Boolean> isSet(Mono<T> mono) {
+		return mono
+				.map(res -> true)
+				.defaultIfEmpty(false);
+	}
+
 	public static class SinkRWStream<T> implements io.vertx.core.streams.WriteStream<T>, io.vertx.core.streams.ReadStream<T> {
 
 		private final Many<T> sink;