Feature - add SORT_RO command #4111

redisson/src/main/java/org/redisson/command/CommandAsyncService.java

@@ -589,9 +589,32 @@ public class CommandAsyncService implements CommandAsyncExecutor {
         NodeSource source = getNodeSource(key);
         return async(false, source, codec, command, params, false, false);
     }
+
+    private final AtomicBoolean sortRoSupported = new AtomicBoolean(true);
     
     public <V, R> RFuture<R> async(boolean readOnlyMode, NodeSource source, Codec codec,
             RedisCommand<V> command, Object[] params, boolean ignoreRedirect, boolean noRetry) {
+        if (readOnlyMode && command.getName().equals("SORT") && !sortRoSupported.get()) {
+            readOnlyMode = false;
+        } else if (readOnlyMode && command.getName().equals("SORT") && sortRoSupported.get()) {
+            RedisCommand cmd = new RedisCommand("SORT_RO", command.getReplayMultiDecoder());
+            CompletableFuture<R> mainPromise = createPromise();
+            RedisExecutor<V, R> executor = new RedisExecutor<>(readOnlyMode, source, codec, cmd, params, mainPromise,
+                    ignoreRedirect, connectionManager, objectBuilder, referenceType, noRetry);
+            executor.execute();
+            CompletableFuture<R> result = new CompletableFuture<>();
+            mainPromise.whenComplete((r, e) -> {
+                if (e != null && e.getMessage().startsWith("ERR unknown command")) {
+                    sortRoSupported.set(false);
+                    RFuture<R> future = async(false, source, codec, command, params, ignoreRedirect, noRetry);
+                    transfer(future.toCompletableFuture(), result);
+                    return;
+                }
+                transfer(mainPromise, result);
+            });
+            return new CompletableFutureWrapper<>(result);
+        }
+
         CompletableFuture<R> mainPromise = createPromise();
         RedisExecutor<V, R> executor = new RedisExecutor<>(readOnlyMode, source, codec, command, params, mainPromise,
                                                     ignoreRedirect, connectionManager, objectBuilder, referenceType, noRetry);