Add GerritSSHClient

Add initial version of GerritSSHClient, which is a wrapper for
paramiko's SSHClient.

The class derives from SSHClient and configures the ssh
connection from the user's ssh config file.

Change-Id: I54a193e41356de272c95c5288ed2c9e50a776cdf

1 files changed, 53 insertions, 0 deletions

diff --git a/pygerrit/ssh.py b/pygerrit/ssh.py
new file mode 100644
index 0000000..35de375
--- /dev/null
+++ b/pygerrit/ssh.py
@@ -0,0 +1,53 @@
+""" Gerrit SSH Client. """
+
+from os.path import abspath, expanduser, isfile
+
+from pygerrit.error import GerritError
+
+from paramiko import SSHClient, SSHConfig
+
+
+class GerritSSHClient(SSHClient):
+
+    """ Gerrit SSH Client, wrapping the paramiko SSH Client. """
+
+    def __init__(self, hostname):
+        """ Initialise and connect to SSH. """
+        super(GerritSSHClient, self).__init__()
+        self.load_system_host_keys()
+
+        configfile = expanduser("~/.ssh/config")
+        if not isfile(configfile):
+            raise GerritError("ssh config file '%s' does not exist" %
+                              configfile)
+
+        config = SSHConfig()
+        config.parse(open(configfile))
+        data = config.lookup(hostname)
+        if not data:
+            raise GerritError("No ssh config for host %s" % hostname)
+        if not 'hostname' in data or not 'port' in data or not 'user' in data:
+            raise GerritError("Missing configuration data in %s" % configfile)
+        key_filename = None
+        if 'identityfile' in data:
+            key_filename = abspath(expanduser(data['identityfile']))
+            if not isfile(key_filename):
+                raise GerritError("Identity file '%s' does not exist" %
+                                  key_filename)
+        self.connect(hostname=data['hostname'],
+                     port=int(data['port']),
+                     username=data['user'],
+                     key_filename=key_filename)
+
+    def run_gerrit_command(self, command):
+        """ Run the given command.
+
+        Run `command` and return a tuple of stdin, stdout, and stderr.
+
+        """
+        gerrit_command = ["gerrit"]
+        if isinstance(command, list):
+            gerrit_command += command
+        else:
+            gerrit_command.append(command)
+        return self.exec_command(" ".join(gerrit_command))