tools: tc-testing: nsPlugin

Move the functionality of creating a namespace before the test suite
and destroying it afterwards to a plugin.
Signed-off-by: Brenda J. Butler <bjb@mojatatu.com>
Acked-by: Lucas Bates <lucasb@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tools/testing/selftests/tc-testing/plugin-lib/nsPlugin.py

+import os
+import signal
+from string import Template
+import subprocess
+import time
+from TdcPlugin import TdcPlugin
+
+from tdc_config import *
+
+class SubPlugin(TdcPlugin):
+    def __init__(self):
+        self.sub_class = 'ns/SubPlugin'
+        super().__init__()
+
+    def pre_suite(self, testcount, testidlist):
+        '''run commands before test_runner goes into a test loop'''
+        super().pre_suite(testcount, testidlist)
+
+        if self.args.namespace:
+            self._ns_create()
+
+    def post_suite(self, index):
+        '''run commands after test_runner goes into a test loop'''
+        super().post_suite(index)
+        if self.args.verbose:
+            print('{}.post_suite'.format(self.sub_class))
+
+        if self.args.namespace:
+            self._ns_destroy()
+
+    def add_args(self, parser):
+        super().add_args(parser)
+        self.argparser_group = self.argparser.add_argument_group(
+            'netns',
+            'options for nsPlugin(run commands in net namespace)')
+        self.argparser_group.add_argument(
+            '-n', '--namespace', action='store_true',
+            help='Run commands in namespace')
+        return self.argparser
+
+    def adjust_command(self, stage, command):
+        super().adjust_command(stage, command)
+        cmdform = 'list'
+        cmdlist = list()
+
+        if not self.args.namespace:
+            return command
+
+        if self.args.verbose:
+            print('{}.adjust_command'.format(self.sub_class))
+
+        if not isinstance(command, list):
+            cmdform = 'str'
+            cmdlist = command.split()
+        else:
+            cmdlist = command
+        if stage == 'setup' or stage == 'execute' or stage == 'verify' or stage == 'teardown':
+            if self.args.verbose:
+                print('adjust_command:  stage is {}; inserting netns stuff in command [{}] list [{}]'.format(stage, command, cmdlist))
+            cmdlist.insert(0, self.args.NAMES['NS'])
+            cmdlist.insert(0, 'exec')
+            cmdlist.insert(0, 'netns')
+            cmdlist.insert(0, 'ip')
+        else:
+            pass
+
+        if cmdform == 'str':
+            command = ' '.join(cmdlist)
+        else:
+            command = cmdlist
+
+        if self.args.verbose:
+            print('adjust_command:  return command [{}]'.format(command))
+        return command
+
+    def _ns_create(self):
+        '''
+        Create the network namespace in which the tests will be run and set up
+        the required network devices for it.
+        '''
+        if self.args.namespace:
+            cmd = 'ip netns add {}'.format(self.args.NAMES['NS'])
+            self._exec_cmd('pre', cmd)
+            cmd = 'ip link add $DEV0 type veth peer name $DEV1'
+            self._exec_cmd('pre', cmd)
+            cmd = 'ip link set $DEV1 netns {}'.format(self.args.NAMES['NS'])
+            self._exec_cmd('pre', cmd)
+            cmd = 'ip link set $DEV0 up'
+            self._exec_cmd('pre', cmd)
+            cmd = 'ip -n {} link set $DEV1 up'.format(self.args.NAMES['NS'])
+            self._exec_cmd('pre', cmd)
+            if self.args.device:
+                cmd = 'ip link set $DEV2 netns {}'.format(self.args.NAMES['NS'])
+                self._exec_cmd('pre', cmd)
+                cmd = 'ip -n {} link set $DEV2 up'.format(self.args.NAMES['NS'])
+                self._exec_cmd('pre', cmd)
+
+    def _ns_destroy(self):
+        '''
+        Destroy the network namespace for testing (and any associated network
+        devices as well)
+        '''
+        if self.args.namespace:
+            cmd = 'ip netns delete {}'.format(self.args.NAMES['NS'])
+            self._exec_cmd('post', cmd)
+
+    def _exec_cmd(self, stage, command):
+        '''
+        Perform any required modifications on an executable command, then run
+        it in a subprocess and return the results.
+        '''
+        if '$' in command:
+            command = self._replace_keywords(command)
+
+        self.adjust_command(stage, command)
+        if self.args.verbose:
+            print('_exec_cmd:  command "{}"'.format(command))
+        proc = subprocess.Popen(command,
+            shell=True,
+            stdout=subprocess.PIPE,
+            stderr=subprocess.PIPE,
+            env=ENVIR)
+        (rawout, serr) = proc.communicate()
+
+        if proc.returncode != 0 and len(serr) > 0:
+            foutput = serr.decode("utf-8")
+        else:
+            foutput = rawout.decode("utf-8")
+
+        proc.stdout.close()
+        proc.stderr.close()
+        return proc, foutput
+
+    def _replace_keywords(self, cmd):
+        """
+        For a given executable command, substitute any known
+        variables contained within NAMES with the correct values
+        """
+        tcmd = Template(cmd)
+        subcmd = tcmd.safe_substitute(self.args.NAMES)
+        return subcmd

tools/testing/selftests/tc-testing/tdc.py

@@ -23,8 +23,6 @@ from tdc_helper import *
 
 import TdcPlugin
 
-USE_NS = True
-
 class PluginMgr:
     def __init__(self, argparser):
         super().__init__()
@@ -107,16 +105,13 @@ def replace_keywords(cmd):
     return subcmd
 
 
-def exec_cmd(args, pm, stage, command, nsonly=True):
+def exec_cmd(args, pm, stage, command):
     """
     Perform any required modifications on an executable command, then run
     it in a subprocess and return the results.
     """
     if len(command.strip()) == 0:
         return None, None
-    if (USE_NS and nsonly):
-        command = 'ip netns exec $NS ' + command
-
     if '$' in command:
         command = replace_keywords(command)
 
@@ -265,39 +260,6 @@ def test_runner(pm, args, filtered_tests):
 
     return tap
 
-
-def ns_create(args, pm):
-    """
-    Create the network namespace in which the tests will be run and set up
-    the required network devices for it.
-    """
-    if (USE_NS):
-        cmd = 'ip netns add $NS'
-        exec_cmd(args, pm, 'pre', cmd, False)
-        cmd = 'ip link add $DEV0 type veth peer name $DEV1'
-        exec_cmd(args, pm, 'pre', cmd, False)
-        cmd = 'ip link set $DEV1 netns $NS'
-        exec_cmd(args, pm, 'pre', cmd, False)
-        cmd = 'ip link set $DEV0 up'
-        exec_cmd(args, pm, 'pre', cmd, False)
-        cmd = 'ip -n $NS link set $DEV1 up'
-        exec_cmd(args, pm, 'pre', cmd, False)
-        cmd = 'ip link set $DEV2 netns $NS'
-        exec_cmd(args, pm, 'pre', cmd, False)
-        cmd = 'ip -n $NS link set $DEV2 up'
-        exec_cmd(args, pm, 'pre', cmd, False)
-
-
-def ns_destroy(args, pm):
-    """
-    Destroy the network namespace for testing (and any associated network
-    devices as well)
-    """
-    if (USE_NS):
-        cmd = 'ip netns delete $NS'
-        exec_cmd(args, pm, 'post', cmd, False)
-
-
 def has_blank_ids(idlist):
     """
     Search the list for empty ID fields and return true/false accordingly.
@@ -579,17 +541,12 @@ def set_operation_mode(pm, args):
             list_test_cases(alltests)
             exit(0)
 
-    ns_create(args, pm)
-
     if len(alltests):
         catresults = test_runner(pm, args, alltests)
     else:
         catresults = 'No tests found\n'
     print('All test results: \n\n{}'.format(catresults))
 
-    ns_destroy(args, pm)
-
-
 def main():
     """
     Start of execution; set up argument parser and get the arguments,