add new topology parameter: arch
[csit.git] / resources / libraries / python / ssh.py
index 961f7e2..11b0583 100644 (file)
@@ -56,40 +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.
@@ -104,12 +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()))
 
@@ -150,10 +157,10 @@ class SSH(object):
 
             if time() - start > timeout:
                 raise SSHTimeout(
-                    'Timeout exception.\n'
-                    'Current contents of stdout buffer: {0}\n'
-                    'Current contents of stderr buffer: {1}\n'
-                    .format(stdout.getvalue(), stderr.getvalue())
+                    '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)
@@ -200,6 +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.
 
@@ -220,7 +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:
@@ -230,6 +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
 
@@ -263,10 +294,13 @@ 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', ''), '')
-        for p in prompt:
-            tmp.replace(p, '')
+        for item in prompt:
+            tmp.replace(item, '')
         return tmp
 
     @staticmethod
@@ -277,17 +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(), socket_timeout=10)
+        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))