Fix issue with ssh flags used with scp.

As the '-p' flag attempt to preserve file attributes
with scp, it was making the scp command fail in
contexts where preserving attributes is not possible
(this is without mentionning the '22' argument that
followed and which seems to be accepted silently).

nixops/backends/__init__.py

@@ -236,6 +236,10 @@ def get_ssh_flags(self, scp=False):
  else:
  return ["-p", str(self.ssh_port)]
 
+ def adapt_ssh_flag_for_use_with_scp(self, flags):
+ # For scp, the "-P" flag is used to specify the port. "-p"
+ # attempt to preserve file attributes.
+ return (map (lambda x: '-P' if x == '-p' else x, flags))
 
  def get_ssh_password(self):
  return None
@@ -353,15 +357,15 @@ def generate_vpn_key(self, check=False):
 
  def upload_file(self, source, target, recursive=False):
  master = self.ssh.get_master()
- cmdline = ["scp"] + self.get_ssh_flags(True) + master.opts
+ cmdline = ["scp"] + self.adapt_ssh_flag_for_use_with_scp(master.opts)
  if recursive:
  cmdline += ['-r']
  cmdline += [source, "root@" + self.get_ssh_name() + ":" + target]
  return self._logged_exec(cmdline)
 
  def download_file(self, source, target, recursive=False):
  master = self.ssh.get_master()
- cmdline = ["scp"] + self.get_ssh_flags(True) + master.opts
+ cmdline = ["scp"] + self.adapt_ssh_flag_for_use_with_scp(master.opts)
  if recursive:
  cmdline += ['-r']
  cmdline += ["root@" + self.get_ssh_name() + ":" + source, target]