CSIT-649 Add library for creating lxc container

Add RF library for manipulating lxc container
Add python library for manipulating lxc container

Change-Id: I02140aa879c7ebd40360d588ab1438c58cf560a1
Signed-off-by: Peter Mikus <pmikus@cisco.com>

3 files changed, 467 insertions, 2 deletions

diff --git a/resources/libraries/python/LXCUtils.py b/resources/libraries/python/LXCUtils.py
new file mode 100644
index 0000000000..3f251a0db1
--- /dev/null
+++ b/resources/libraries/python/LXCUtils.py
@@ -0,0 +1,375 @@
+# Copyright (c) 2017 Cisco and/or its affiliates.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at:
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""Library to manipulate LXC."""
+
+from resources.libraries.python.ssh import SSH
+from resources.libraries.python.topology import NodeType
+
+__all__ = ["LXCUtils"]
+
+class LXCUtils(object):
+    """LXC utilities."""
+
+    def __init__(self, container_name='slave'):
+        # LXC container name
+        self._container_name = container_name
+        self._node = None
+        # Host dir that will be mounted inside LXC
+        self._host_dir = '/tmp/'
+        # Guest dir to mount host dir to
+        self._guest_dir = '/mnt/host'
+        # LXC container env variables
+        self._env_vars = ['LC_ALL="en_US.UTF-8"',
+                          'DEBIAN_FRONTEND=noninteractive']
+
+    def set_node(self, node):
+        """Set node for LXC execution.
+
+        :param node: Node to execute LXC on.
+        :type node: dict
+        :raises RuntimeError: If Node type is not DUT.
+        """
+        if node['type'] != NodeType.DUT:
+            raise RuntimeError('Node type is not DUT.')
+        self._node = node
+
+    def set_host_dir(self, node, host_dir):
+        """Set shared dir on parent node for LXC.
+
+        :param node: Node to control LXC on.
+        :type node: dict
+        :raises RuntimeError: If Node type is not DUT.
+        """
+        if node['type'] != NodeType.DUT:
+            raise RuntimeError('Node type is not DUT.')
+        self._host_dir = host_dir
+
+    def set_guest_dir(self, node, guest_dir):
+        """Set mount dir on LXC.
+
+        :param node: Node to control LXC on.
+        :param guest_dir: Guest dir for mount.
+        :type node: dict
+        :type guest_dir: str
+        :raises RuntimeError: If Node type is not DUT.
+        """
+        if node['type'] != NodeType.DUT:
+            raise RuntimeError('Node type is not DUT.')
+        self._guest_dir = guest_dir
+
+    def _lxc_checkconfig(self):
+        """Check the current kernel for LXC support.
+
+        :raises RuntimeError: If failed to check LXC support.
+        """
+
+        ssh = SSH()
+        ssh.connect(self._node)
+
+        ret, _, _ = ssh.exec_command_sudo('lxc-checkconfig')
+        if int(ret) != 0:
+            raise RuntimeError('Failed to check LXC support.')
+
+    def _lxc_create(self, distro='ubuntu', release='xenial', arch='amd64'):
+        """Creates a privileged system object where is stored the configuration
+        information and where can be stored user information.
+
+        :param distro: Linux distribution name.
+        :param release: Linux distribution release.
+        :param arch: Linux distribution architecture.
+        :type distro: str
+        :type release: str
+        :type arch: str
+        :raises RuntimeError: If failed to create a container.
+        """
+
+        ssh = SSH()
+        ssh.connect(self._node)
+
+        ret, _, _ = ssh.exec_command_sudo(
+            'lxc-create -t download --name {0} -- -d {1} -r {2} -a {3}'
+            .format(self._container_name, distro, release, arch), timeout=1800)
+        if int(ret) != 0:
+            raise RuntimeError('Failed to create LXC container.')
+
+    def _lxc_info(self):
+        """Queries and shows information about a container.
+
+        :raises RuntimeError: If failed to get info about a container.
+        """
+
+        ssh = SSH()
+        ssh.connect(self._node)
+
+        ret, _, _ = ssh.exec_command_sudo(
+            'lxc-info --name {0}'.format(self._container_name))
+        if int(ret) != 0:
+            raise RuntimeError('Failed to get info about LXC container {0}.'
+                               .format(self._container_name))
+
+    def _lxc_start(self):
+        """Start an application inside a container.
+
+        :raises RuntimeError: If failed to start container.
+        """
+
+        ssh = SSH()
+        ssh.connect(self._node)
+
+        ret, _, _ = ssh.exec_command_sudo(
+            'lxc-start --name {0} --daemon'.format(self._container_name))
+        if int(ret) != 0:
+            raise RuntimeError('Failed to start LXC container {0}.'
+                               .format(self._container_name))
+
+    def _lxc_stop(self):
+        """Stop an application inside a container.
+
+        :raises RuntimeError: If failed to stop container.
+        """
+
+        ssh = SSH()
+        ssh.connect(self._node)
+
+        ret, _, _ = ssh.exec_command_sudo(
+            'lxc-stop --name {0}'.format(self._container_name))
+        if int(ret) != 0:
+            raise RuntimeError('Failed to stop LXC container {}.'
+                               .format(self._container_name))
+
+    def _lxc_destroy(self):
+        """Destroy a container.
+
+        :raises RuntimeError: If failed to destroy container.
+        """
+
+        ssh = SSH()
+        ssh.connect(self._node)
+
+        ret, _, _ = ssh.exec_command_sudo(
+            'lxc-destroy --force --name {0}'.format(self._container_name))
+        if int(ret) != 0:
+            raise RuntimeError('Failed to destroy LXC container {}.'
+                               .format(self._container_name))
+
+    def _lxc_wait(self, state):
+        """Wait for a specific container state.
+
+        :param state: Specify the container state(s) to wait for.
+        :type state: str
+        :raises RuntimeError: If failed to wait for state of a container.
+        """
+
+        ssh = SSH()
+        ssh.connect(self._node)
+
+        ret, _, _ = ssh.exec_command_sudo(
+            'lxc-wait --name {0} --state "{1}"'
+            .format(self._container_name, state))
+        if int(ret) != 0:
+            raise RuntimeError('Failed to wait for "{0}" of LXC container {1}.'
+                               .format(state, self._container_name))
+
+    def _lxc_cgroup(self, state_object, value=''):
+        """Manage the control group associated with a container.
+
+        :param state_object: Specify the state object name.
+        :param value: Specify the value to assign to the state object. If empty,
+        then action is GET, otherwise is action SET.
+        :type state_object: str
+        :type value: str
+        :raises RuntimeError: If failed to get/set for state of a container.
+        """
+
+        ssh = SSH()
+        ssh.connect(self._node)
+
+        ret, _, _ = ssh.exec_command_sudo(
+            'lxc-cgroup --name {0} {1} {2}'
+            .format(self._container_name, state_object, value))
+        if int(ret) != 0:
+            if value:
+                raise RuntimeError('Failed to set {0} of LXC container {1}.'
+                                   .format(state_object, self._container_name))
+            else:
+                raise RuntimeError('Failed to get {0} of LXC container {1}.'
+                                   .format(state_object, self._container_name))
+
+    def lxc_attach(self, command):
+        """Start a process inside a running container. Runs the specified
+        command inside the container specified by name. The container has to
+        be running already.
+
+        :param command: Command to run inside container.
+        :type command: str
+        :raises RuntimeError: If container is not running.
+        :raises RuntimeError: If failed to run the command.
+        """
+        env_var = '--keep-env {0}'\
+            .format(' '.join('--set-var %s' % var for var in self._env_vars))
+
+        ssh = SSH()
+        ssh.connect(self._node)
+
+        if not self.is_container_running():
+            raise RuntimeError('LXC {0} is not running.'
+                               .format(self._container_name))
+
+        ret, _, _ = ssh.exec_command_lxc(lxc_cmd=command,
+                                         lxc_name=self._container_name,
+                                         lxc_params=env_var, timeout=180)
+        if int(ret) != 0:
+            raise RuntimeError('Failed to run "{0}" on LXC container {1}.'
+                               .format(command, self._container_name))
+
+    def is_container_present(self):
+        """Check if LXC container is existing on node."""
+
+        ssh = SSH()
+        ssh.connect(self._node)
+
+        ret, _, _ = ssh.exec_command_sudo(
+            'lxc-info --name {0}'.format(self._container_name))
+        return False if int(ret) else True
+
+    def create_container(self, force_create=True):
+        """Create and start a container.
+
+        :param force_create: Destroy a container if exists and create.
+        :type force_create: bool
+        """
+        if self.is_container_present():
+            if force_create:
+                self.container_destroy()
+            else:
+                return
+
+        self._lxc_checkconfig()
+        self._lxc_create(distro='ubuntu', release='xenial', arch='amd64')
+        self.start_container()
+
+    def start_container(self):
+        """Start a container and wait for running state."""
+
+        self._lxc_start()
+        self._lxc_wait('RUNNING')
+        self._lxc_info()
+
+    def is_container_running(self):
+        """Check if LXC container is running on node.
+
+        :raises RuntimeError: If failed to get info about a container.
+        """
+
+        ssh = SSH()
+        ssh.connect(self._node)
+
+        ret, stdout, _ = ssh.exec_command_sudo(
+            'lxc-info --state --name {0}'.format(self._container_name))
+        if int(ret) != 0:
+            raise RuntimeError('Failed to get info about LXC container {0}.'
+                               .format(self._container_name))
+
+        return True if 'RUNNING' in stdout else False
+
+    def stop_container(self):
+        """Stop a container and wait for stopped state."""
+
+        self._lxc_stop()
+        self._lxc_wait('STOPPED|FROZEN')
+        self._lxc_info()
+
+    def restart_container(self):
+        """Restart container."""
+
+        self.stop_container()
+        self.start_container()
+
+    def container_destroy(self):
+        """Stop and destroy a container."""
+
+        self._lxc_destroy()
+
+    def container_cpuset_cpus(self, container_cpu):
+        """Set cpuset.cpus control group associated with a container.
+
+        :param container_cpu: Cpuset.cpus string.
+        :type container_cpu: str
+        :raises RuntimeError: If failed to set cgroup for a container.
+        """
+
+        ssh = SSH()
+        ssh.connect(self._node)
+
+        ret, _, _ = ssh.exec_command_sudo('cgset --copy-from / lxc')
+        if int(ret) != 0:
+            raise RuntimeError('Failed to copy cgroup settings from root.')
+
+        self._lxc_cgroup(state_object='cpuset.cpus')
+        self._lxc_cgroup(state_object='cpuset.cpus', value=container_cpu)
+        self._lxc_cgroup(state_object='cpuset.cpus')
+
+    def mount_host_dir_in_container(self):
+        """Mount shared folder inside container.
+
+        :raises RuntimeError: If failed to mount host dir in a container.
+        """
+
+        ssh = SSH()
+        ssh.connect(self._node)
+
+        self.lxc_attach('mkdir -p {0}'.format(self._guest_dir))
+
+        mnt_cfg = 'lxc.mount.entry = {0} /var/lib/lxc/{1}/rootfs{2} ' \
+            'none bind 0 0'.format(self._host_dir, self._container_name,
+                                   self._guest_dir)
+        ret, _, _ = ssh.exec_command_sudo(
+            "sh -c 'echo \"{0}\" >> /var/lib/lxc/{1}/config'"
+            .format(mnt_cfg, self._container_name))
+        if int(ret) != 0:
+            raise RuntimeError('Failed to mount {0} in lxc: {1}'
+                               .format(self._host_dir, self._container_name))
+
+        self.restart_container()
+
+    def install_vpp_in_container(self, install_dkms=False):
+        """Install vpp inside a container.
+
+        :param install_dkms: If install dkms package. This will impact install
+        time. Dkms is required for installation of vpp-dpdk-dkms. Default is
+        false.
+        :type install_dkms: bool
+        """
+
+        ssh = SSH()
+        ssh.connect(self._node)
+
+        self.lxc_attach('apt-get update')
+        if install_dkms:
+            self.lxc_attach('apt-get install -y dkms && '
+                            'dpkg -i --force-all {0}/install_dir/*.deb'
+                            .format(self._guest_dir))
+        else:
+            self.lxc_attach('for i in $(ls -I \"*dkms*\" {0}/install_dir/); '
+                            'do dpkg -i --force-all {0}/install_dir/$i; done'
+                            .format(self._guest_dir))
+        self.lxc_attach('apt-get -f install -y')
+
+    def restart_vpp_in_container(self):
+        """Restart vpp service inside a container."""
+
+        ssh = SSH()
+        ssh.connect(self._node)
+
+        self.lxc_attach('service vpp restart')
diff --git a/resources/libraries/python/VppConfigGenerator.py b/resources/libraries/python/VppConfigGenerator.py
index 039f629309..31defd6704 100644
--- a/resources/libraries/python/VppConfigGenerator.py
+++ b/resources/libraries/python/VppConfigGenerator.py
@@ -123,7 +123,6 @@ class VppConfigGenerator(object):
         """
         path = ['unix', 'cli-listen']
         self.add_config_item(self._nodeconfig, value, path)
-        self._nodeconfig = {'unix': {'nodaemon': ''}}
 
     def add_unix_nodaemon(self):
         """Add UNIX nodaemon configuration."""
@@ -228,7 +227,7 @@ class VppConfigGenerator(object):
     def add_api_trace(self):
         """Add API trace configuration."""
         path = ['api-trace', 'on']
-        self.add_config_item(self._nodeconfig, path, '')
+        self.add_config_item(self._nodeconfig, '', path)
 
     def add_ip6_hash_buckets(self, value):
         """Add IP6 hash buckets configuration.
@@ -248,6 +247,16 @@ class VppConfigGenerator(object):
         path = ['ip6', 'heap-size']
         self.add_config_item(self._nodeconfig, value, path)
 
+    def add_plugin_disable(self, *plugins):
+        """Add plugin disable for specific plugin.
+
+        :param plugins: Plugin(s) to disable.
+        :type plugins: list
+        """
+        for plugin in plugins:
+            path = ['plugins', 'plugin {0}'.format(plugin), 'disable']
+            self.add_config_item(self._nodeconfig, ' ', path)
+
     def add_dpdk_no_multi_seg(self):
         """Add DPDK no-multi-seg configuration."""
         path = ['dpdk', 'no-multi-seg']
@@ -316,3 +325,61 @@ class VppConfigGenerator(object):
         else:
             raise RuntimeError('VPP failed to restart on node {}'.
                                format(self._hostname))
+
+    def apply_config_lxc(self, lxc_name, waittime=5, retries=12):
+        """Generate and apply VPP configuration for node in a container.
+
+        Use data from calls to this class to form a startup.conf file and
+        replace /etc/vpp/startup.conf with it on node inside a container.
+
+        :param lxc_name: LXC container name.
+        :param waittime: Time to wait for VPP to restart (default 5 seconds).
+        :param retries: Number of times (default 12) to re-try waiting.
+        :type lxc_name: str
+        :type waittime: int
+        :type retries: int
+        :raises RuntimeError: If writing config file failed, or restarting of
+        VPP failed.
+        """
+        self.dump_config(self._nodeconfig)
+
+        ssh = SSH()
+        ssh.connect(self._node)
+
+        # We're using this "| sudo tee" construct because redirecting
+        # a sudo's output ("sudo echo xxx > /path/to/file") does not
+        # work on most platforms...
+        (ret, _, _) = \
+            ssh.exec_command_lxc('echo "{0}" | sudo tee {1}'.
+                                 format(self._vpp_config,
+                                        self._vpp_config_filename), lxc_name)
+
+        if ret != 0:
+            raise RuntimeError('Writing config file failed in {0} to node {1}'.
+                               format(lxc_name, self._hostname))
+
+        # Instead of restarting, we'll do separate start and stop
+        # actions. This way we don't care whether VPP was running
+        # to begin with.
+        ssh.exec_command_lxc('service {0} stop'.
+                             format(self._vpp_service_name), lxc_name)
+        (ret, _, _) = \
+            ssh.exec_command_lxc('service {0} start'.
+                                 format(self._vpp_service_name), lxc_name)
+        if ret != 0:
+            raise RuntimeError('Restarting VPP failed in {0} on node {1}'.
+                               format(lxc_name, self._hostname))
+
+        # Sleep <waittime> seconds, up to <retry> times,
+        # and verify if VPP is running.
+        for _ in range(retries):
+            time.sleep(waittime)
+            (ret, _, _) = \
+                ssh.exec_command_lxc('echo show hardware-interfaces | '
+                                     'nc 0 5002 || echo "VPP not yet running"',
+                                     lxc_name)
+            if ret == 0:
+                break
+        else:
+            raise RuntimeError('VPP failed to restart in {0} on node {1}'.
+                               format(lxc_name, self._hostname))
diff --git a/resources/libraries/python/ssh.py b/resources/libraries/python/ssh.py
index f59bd02e25..db39a0701c 100644
--- a/resources/libraries/python/ssh.py
+++ b/resources/libraries/python/ssh.py
@@ -207,6 +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.