[PATCH v2 01/16] HostAPI: Add enable / disable service methods

[Ido Schimmel]

From: Ido Schimmel <idosch(a)mellanox.com&gt;

We are going to need to enable the lldpad service from the QoS recipes,
so we might as well provide generic enable / disable methods for recipes
to use.

In order to support both Systemd and SysVinit systems the requested
service is configured using 'systemctl' or 'service', depending on the
output of `pidof systemd`.

Suggested-by: Ondrej Lichtner <olichtne(a)redhat.com&gt;
Signed-off-by: Ido Schimmel <idosch(a)mellanox.com&gt;
---
 lnst/Controller/Machine.py | 18 ++++++++++++++++++
 lnst/Controller/Task.py    |  6 ++++++
 lnst/Slave/NetTestSlave.py | 18 ++++++++++++++++++
 3 files changed, 42 insertions(+)

diff --git a/lnst/Controller/Machine.py b/lnst/Controller/Machine.py
index 70295ba..ec1a72b 100644
--- a/lnst/Controller/Machine.py
+++ b/lnst/Controller/Machine.py
@@ -74,6 +74,7 @@ class Machine(object):
 
         self._interfaces = []
         self._namespaces = []
+        self._services = []
         self._bg_cmds = {}
 
         self._device_database = {}
@@ -332,6 +333,7 @@ class Machine(object):
                 for iface in ordered_ifaces:
                     iface.cleanup()
 
+                self.disable_services()
                 self.del_namespaces()
 
             self.restore_nm_option()
@@ -578,6 +580,22 @@ class Machine(object):
     def get_security(self):
         return self._security
 
+    def enable_service(self, service):
+        self._services.append(service)
+        return self._rpc_call("enable_service", service)
+
+    def disable_service(self, service):
+        try:
+            self._services.remove(service)
+        except ValueError:
+            return False
+        return self._rpc_call("disable_service", service)
+
+    def disable_services(self):
+        for service in self._services:
+            self.disable_service(service)
+        return True
+
 class Interface(object):
     """ Abstraction of a test network interface on a slave machine
 
diff --git a/lnst/Controller/Task.py b/lnst/Controller/Task.py
index f9a15f2..4fa5f4a 100644
--- a/lnst/Controller/Task.py
+++ b/lnst/Controller/Task.py
@@ -489,6 +489,12 @@ class HostAPI(object):
 
         return self._add_iface("vxlan", if_id, netns, ip, options, slaves)
 
+    def enable_service(self, service):
+        return self._m.enable_service(service)
+
+    def disable_service(self, service):
+        return self._m.disable_service(service)
+
 class DeviceAPI(object):
     def __init__(self, net_device, host):
         self._dev = net_device
diff --git a/lnst/Slave/NetTestSlave.py b/lnst/Slave/NetTestSlave.py
index f0b3183..2636556 100644
--- a/lnst/Slave/NetTestSlave.py
+++ b/lnst/Slave/NetTestSlave.py
@@ -903,6 +903,24 @@ class SlaveMethods:
             return False
         return True
 
+    def _is_systemd(self):
+        stdout, _ = exec_cmd("pidof systemd", die_on_err=False)
+        return len(stdout) != 0
+
+    def _configure_service(self, service, start=True):
+        action = "start" if start else "stop"
+        if self._is_systemd():
+            exec_cmd("systemctl {} {}".format(action, service))
+        else:
+            exec_cmd("service {} {}".format(service, action))
+        return True
+
+    def enable_service(self, service):
+        return self._configure_service(service)
+
+    def disable_service(self, service):
+        return self._configure_service(service, start=False)
+
 class ServerHandler(ConnectionHandler):
     def __init__(self, addr):
         super(ServerHandler, self).__init__()
-- 
2.7.4