'Returns the client\'s SSL certificate, if any.
To use client certificates, the HTTPServer must have been constructed
with cert_reqs set in ssl_options, e.g.::
server = HTTPServer(app,
ssl_options=dict(
certfile="foo.crt",
keyfile="foo.key",
cert_reqs=ssl.CERT_REQUIRED,
ca_certs="cacert.crt"))
By default, the return value is a dictionary (or None, if no
client certificate is present).  If ``binary_form`` is true, a
DER-encoded form of the certificate is returned instead.  See
SSLSocket.getpeercert() in the standard library for more
details.
http://docs.python.org/library/ssl.html#sslsocket-objects'

def get_ssl_certificate(self, binary_form=False):

    try:
        return self.connection.stream.socket.getpeercert(binary_form=binary_form)
    except SSLError:
        return None
