X-Git-Url: https://gerrit.fd.io/r/gitweb?p=csit.git;a=blobdiff_plain;f=resources%2Flibraries%2Fpython%2Fssh.py;h=11b05837bf1a2d3e9db51900d26401e7e053d431;hp=4b3838bbb79159212e8c0efa4193fb7f532a879c;hb=c7eb2002bcd007520309feb3e11a26ff847a4e05;hpb=19afb923ce31fa51291d12b79d8b63cfce09ab14 diff --git a/resources/libraries/python/ssh.py b/resources/libraries/python/ssh.py index 4b3838bbb7..11b05837bf 100644 --- a/resources/libraries/python/ssh.py +++ b/resources/libraries/python/ssh.py @@ -29,6 +29,11 @@ __all__ = ["exec_cmd", "exec_cmd_no_error"] # TODO: load priv key +class SSHTimeout(Exception): + """This exception is raised when a timeout occurs.""" + pass + + class SSH(object): """Contains methods for managing and using SSH connections.""" @@ -51,40 +56,47 @@ class SSH(object): return hash(frozenset([node['host'], node['port']])) - def connect(self, node): + def connect(self, node, attempts=5): """Connect to node prior to running exec_command or scp. If there already is a connection to the node, this method reuses it. """ - self._node = node - node_hash = self._node_hash(node) - if node_hash in SSH.__existing_connections: - self._ssh = SSH.__existing_connections[node_hash] - logger.debug('reusing ssh: {0}'.format(self._ssh)) - else: - start = time() - pkey = None - if 'priv_key' in node: - pkey = RSAKey.from_private_key( - StringIO.StringIO(node['priv_key'])) - - self._ssh = paramiko.SSHClient() - self._ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy()) - - self._ssh.connect(node['host'], username=node['username'], - password=node.get('password'), pkey=pkey, - port=node['port']) - - self._ssh.get_transport().set_keepalive(10) - - SSH.__existing_connections[node_hash] = self._ssh - - logger.trace('connect took {} seconds'.format(time() - start)) - logger.debug('new ssh: {0}'.format(self._ssh)) - - logger.debug('Connect peer: {0}'. - format(self._ssh.get_transport().getpeername())) - logger.debug('Connections: {0}'.format(str(SSH.__existing_connections))) + try: + self._node = node + node_hash = self._node_hash(node) + if node_hash in SSH.__existing_connections: + self._ssh = SSH.__existing_connections[node_hash] + logger.debug('reusing ssh: {0}'.format(self._ssh)) + else: + start = time() + pkey = None + if 'priv_key' in node: + pkey = RSAKey.from_private_key( + StringIO.StringIO(node['priv_key'])) + + self._ssh = paramiko.SSHClient() + self._ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy()) + + self._ssh.connect(node['host'], username=node['username'], + password=node.get('password'), pkey=pkey, + port=node['port']) + + self._ssh.get_transport().set_keepalive(10) + + SSH.__existing_connections[node_hash] = self._ssh + + logger.trace('connect took {} seconds'.format(time() - start)) + logger.debug('new ssh: {0}'.format(self._ssh)) + + logger.debug('Connect peer: {0}'. + format(self._ssh.get_transport().getpeername())) + logger.debug('Connections: {0}'. + format(str(SSH.__existing_connections))) + except: + if attempts > 0: + self._reconnect(attempts-1) + else: + raise def disconnect(self, node): """Close SSH connection to the node. @@ -99,12 +111,12 @@ class SSH(object): ssh = SSH.__existing_connections.pop(node_hash) ssh.close() - def _reconnect(self): + def _reconnect(self, attempts=0): """Close the SSH connection and open it again.""" node = self._node self.disconnect(node) - self.connect(node) + self.connect(node, attempts) logger.debug('Reconnecting peer done: {}'. format(self._ssh.get_transport().getpeername())) @@ -118,7 +130,7 @@ class SSH(object): :type timeout: int :return return_code, stdout, stderr :rtype: tuple(int, str, str) - :raise socket.timeout: If command is not finished in timeout time. + :raise SSHTimeout: If command is not finished in timeout time. """ start = time() stdout = StringIO.StringIO() @@ -144,11 +156,11 @@ class SSH(object): stderr.write(chan.recv_stderr(self.__MAX_RECV_BUF)) if time() - start > timeout: - raise socket.timeout( - 'Timeout exception.\n' - 'Current contents of stdout buffer: {0}\n' - 'Current contents of stderr buffer: {1}\n' - .format(stdout.getvalue(), stderr.getvalue()) + raise SSHTimeout( + 'Timeout exception during execution of command: {0}\n' + 'Current contents of stdout buffer: {1}\n' + 'Current contents of stderr buffer: {2}\n' + .format(cmd, stdout.getvalue(), stderr.getvalue()) ) sleep(0.1) @@ -195,6 +207,29 @@ class SSH(object): command = 'sudo -S {c} <<< "{i}"'.format(c=cmd, i=cmd_input) return self.exec_command(command, timeout) + def exec_command_lxc(self, lxc_cmd, lxc_name, lxc_params='', sudo=True, + timeout=30): + """Execute command in LXC on a new SSH channel on the connected Node. + + :param lxc_cmd: Command to be executed. + :param lxc_name: LXC name. + :param lxc_params: Additional parameters for LXC attach. + :param sudo: Run in privileged LXC mode. Default: privileged + :param timeout: Timeout. + :type lxc_cmd: str + :type lxc_name: str + :type lxc_params: str + :type sudo: bool + :type timeout: int + :return: return_code, stdout, stderr + """ + command = "lxc-attach {p} --name {n} -- /bin/sh -c '{c}'"\ + .format(p=lxc_params, n=lxc_name, c=lxc_cmd) + + if sudo: + command = 'sudo -S {c}'.format(c=command) + return self.exec_command(command, timeout) + def interactive_terminal_open(self, time_out=30): """Open interactive terminal on a new channel on the connected Node. @@ -215,7 +250,7 @@ class SSH(object): chan.set_combine_stderr(True) buf = '' - while not buf.endswith(':~$ '): + while not buf.endswith((":~$ ", "~]$ ", "~]# ")): try: chunk = chan.recv(self.__MAX_RECV_BUF) if not chunk: @@ -225,6 +260,7 @@ class SSH(object): logger.error('Channel exit status ready') break except socket.timeout: + logger.error('Socket timeout: {0}'.format(buf)) raise Exception('Socket timeout: {0}'.format(buf)) return chan @@ -258,9 +294,14 @@ class SSH(object): logger.error('Channel exit status ready') break except socket.timeout: - raise Exception('Socket timeout: {0}'.format(buf)) + logger.error('Socket timeout during execution of command: ' + '{0}\nBuffer content:\n{1}'.format(cmd, buf)) + raise Exception('Socket timeout during execution of command: ' + '{0}\nBuffer content:\n{1}'.format(cmd, buf)) tmp = buf.replace(cmd.replace('\n', ''), '') - return tmp.replace(prompt, '') + for item in prompt: + tmp.replace(item, '') + return tmp @staticmethod def interactive_terminal_close(chan): @@ -270,17 +311,37 @@ class SSH(object): """ chan.close() - def scp(self, local_path, remote_path): - """Copy files from local_path to remote_path. + def scp(self, local_path, remote_path, get=False, timeout=10): + """Copy files from local_path to remote_path or vice versa. connect() method has to be called first! + + :param local_path: Path to local file that should be uploaded; or + path where to save remote file. + :param remote_path: Remote path where to place uploaded file; or + path to remote file which should be downloaded. + :param get: scp operation to perform. Default is put. + :param timeout: Timeout value in seconds. + :type local_path: str + :type remote_path: str + :type get: bool + :type timeout: int """ - logger.trace('SCP {0} to {1}:{2}'.format( - local_path, self._ssh.get_transport().getpeername(), remote_path)) + if not get: + logger.trace('SCP {0} to {1}:{2}'.format( + local_path, self._ssh.get_transport().getpeername(), + remote_path)) + else: + logger.trace('SCP {0}:{1} to {2}'.format( + self._ssh.get_transport().getpeername(), remote_path, + local_path)) # SCPCLient takes a paramiko transport as its only argument - scp = SCPClient(self._ssh.get_transport()) + scp = SCPClient(self._ssh.get_transport(), socket_timeout=timeout) start = time() - scp.put(local_path, remote_path) + if not get: + scp.put(local_path, remote_path) + else: + scp.get(remote_path, local_path) scp.close() end = time() logger.trace('SCP took {0} seconds'.format(end-start)) @@ -301,7 +362,7 @@ def exec_cmd(node, cmd, timeout=600, sudo=False): ssh = SSH() try: ssh.connect(node) - except Exception as err: + except SSHException as err: logger.error("Failed to connect to node" + str(err)) return None, None, None @@ -311,7 +372,7 @@ def exec_cmd(node, cmd, timeout=600, sudo=False): else: (ret_code, stdout, stderr) = ssh.exec_command_sudo(cmd, timeout=timeout) - except Exception as err: + except SSHException as err: logger.error(err) return None, None, None