code: public CMAArray<CMASpaceMembership> fetchAll(String spaceId, Map<String, String> query) {
      assertNotNull(spaceId, "spaceId");
      if (query == null) {
        return service.fetchAll(spaceId).blockingFirst();
      } else {
        return service.fetchAll(spaceId, query).blockingFirst();
      }
    }
docs: Fetch all memberships of this space.
  <p>
  This method will override the configuration specified through
  {@link CMAClient.Builder#setSpaceId(String)} and will ignore
  {@link CMAClient.Builder#setEnvironmentId(String)}.
  
  @param spaceId the space identifier identifying the space.
  @param query   define which space memberships to return.
  @return the array of memberships.
  @throws IllegalArgumentException if spaceId is null.