Comment 4 for bug 1521623

It seems that the observed behavior is a result of sending PUT requests
without specifying Content-Length HTTP header. RFC 7230 states that
the header should be applied [1]:

    "3.3.2. Content-Length
    (...)
    A user agent SHOULD send a Content-Length in a request message when
    no Transfer-Encoding is sent and the request method defines a meaning
    for an enclosed payload body. For example, a Content-Length header
    field is normally sent in a POST request even when the value is 0
    (indicating an empty payload body)."

Most likely the improper requests have not been even delivered to radosgw
instance, but rejected by intermediary Apache server that is used as a FastCGI
front-end to radosgw. We already saw similar behavior in #1505273.

You may enforce curl to generate Content-Length for a request with empty
body through appending "-d ''" or "-H 'Content-Length: 0" to the argument list.

[1] https://tools.ietf.org/html/rfc7230#page-30
[2] https://bugs.launchpad.net/mos/+bug/1505273