code: public CompletableFuture<CreateScopeStatus> createScope(final String scope) {
          Exceptions.checkNotNullOrEmpty(scope, "scope");
          try {
              NameUtils.validateScopeName(scope);
          } catch (IllegalArgumentException | NullPointerException e) {
              log.warn("Create scope failed due to invalid scope name {}", scope);
              return CompletableFuture.completedFuture(CreateScopeStatus.newBuilder().setStatus(
                      CreateScopeStatus.Status.INVALID_SCOPE_NAME).build());
          }
          return streamStore.createScope(scope);
      }
docs: Controller Service API to create scope.
  
  @param scope Name of scope to be created.
  @return Status of create scope.