@GET @ApiIgnore // until documented
  @Produces("text/plain")
  public Response getAuthorizations(@Context HttpHeaders headers, @Context UriInfo ui) {
    return handleRequest(headers, null, ui, Request.Type.GET, createAuthorizationResource(null));
  }
Handles: GET  /permissions/{permission_id}/authorizations
Get all authorizations for the relative permission, or all if this RoleAuthorizationService is
not linked to a particular permission.

@param headers http headers
@param ui      uri info
@return authorizations collection resource representation
ambari-server/src/main/java/org/apache/ambari/server/api/services/RoleAuthorizationService.java