Downloading actual .yaml, .pgm or octomap binary files from roboearth.

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I have uploaded my lab's environment owl description (2D occupancy map), 2D occupancy grid map in .pgm and .yaml file formats on to roboearth DB. But this has been done through roboearth web interface. (http://api.roboearth.org)

Although we can do this through POST command. Could anyone please let me know if there are any ros commands through which these files can be downloaded or this can be done only through JSON (GET command -> tried this but this just gives owl description of environment and not actual file) ?