Better support for multiple commands

This changes the 'commands' YAML portion to be an array. E.g.:

commands:
  - ls
  - ps
  - echo 'Have you tried turning it off and on again?'

Docker doesn't really support issuing multiple commands to a container
on the command line very well. You have to either munge it with something
like:

    sh -c 'ls && ps'

or place all of the commands to execute into a master script, then execute
that script.

This change proposes the second option and creates a master script if the
number of commands is more than one.

The master script file will be created in a .dox subdirectory of the
current directory, and named master_script.sh. Right now, it is created
as a Bourne shell script. We could easily add support later for different
shells.

If the -c option is used, then the command specified is the only command
that will run.

If -c is NOT used, but extra arguments are supplied, these extra arguments
will be used to replace the {posargs} placeholders in tox.ini files. The
extra args are not currently used elsewhere.

This change REMOVES the ability to add extra_args to the end of the
command when {posargs} is NOT present. That does not make sense in
a multi-command situation.

Change-Id: I78dbc0613f5db22cea0ed714f5f30ef0207fac24

dox/cmd.py

@@ -89,8 +89,10 @@ def run_dox(args):
     # Get Command
     if args.command:
         command = dox.config.cmdline.CommandLine(args.extra_args)
+        logger.debug("Command source is the command line")
     else:
         command = dox.commands.Commands(args.extra_args)
+        logger.debug("Command source is %s" % command.source.source_name())
 
     # Run
     try:
@@ -98,6 +100,5 @@ def run_dox(args):
                                 command=command)
         map(run, images)
     except Exception:
-        logger.error(
-            "Operation failed, aborting dox.", exc_info=args.debug)
+        logger.error("Operation failed, aborting dox.", exc_info=args.debug)
         return 1

dox/commands.py

@@ -19,12 +19,12 @@ __all__ = [
 ]
 
 import logging
+import os
 
 import dox.config.dox_yaml
 import dox.config.tox_ini
 import dox.config.travis_yaml
 
-
 logger = logging.getLogger(__name__)
 
 
@@ -37,7 +37,6 @@ def get_commands():
 
     for source in (dox_yaml, tox_ini, travis_yaml):
         if source.exists():
-            logger.debug("Command source is: %s" % source.source_name())
             return source
     raise Exception("dox cannot figure out what command to run")
 
@@ -49,12 +48,42 @@ class Commands(object):
         self.args = []
         self.extra_args = extra_args
 
+    def _test_command_as_script(self, commands, shell='/bin/sh'):
+        """Combine test commands into a master script file.
+
+        The script, using the given shell, will be created in the .dox
+        subdirectory of the current directory.
+
+        :param commands: A list of commands to execute.
+        :param shell: Path to the OS shell to run the commands.
+        """
+        dox_dir = '.dox'
+        master_script = os.path.join(dox_dir, 'master_script.sh')
+
+        if not os.path.exists(dox_dir):
+            os.mkdir(dox_dir, 0o755)
+
+        with open(master_script, "w") as f:
+            f.write("#!" + shell + "\n")
+            f.write("\n".join(commands))
+            f.write("\n")
+
+        os.chmod(master_script, 0o700)
+        return master_script
+
     def test_command(self):
+        """Return the command to execute in the container.
+
+        If there is more than one command, we combine them into a master
+        script to execute. Otherwise, we just issue the command normally
+        on the docker command line.
+        """
         commands = self.source.get_commands(self.extra_args)
-        if hasattr(commands, 'append'):
-            ret = "\n".join(commands)
-        else:
-            ret = commands + ' ' + ' '.join(self.args)
+
+        if len(commands) > 1:
+            return self._test_command_as_script(commands)
+
+        ret = commands[0] + ' ' + ' '.join(self.args)
         return ret.strip()
 
     def prep_commands(self):

dox/config/dox_yaml.py

@@ -54,7 +54,7 @@ class DoxYaml(base.ConfigBase):
         return self._open_dox_yaml().get('images', [])
 
     def get_commands(self, extra_args):
-        return " ".join([self._open_dox_yaml().get('commands')] + extra_args)
+        return self._open_dox_yaml().get('commands', [])
 
     def get_prep_commands(self):
         return self._open_dox_yaml().get('prep', [])

dox/config/tox_ini.py

@@ -56,15 +56,22 @@ class ToxIni(base.ConfigBase):
             return ini.get('docker', 'images', '').split(',')
 
     def get_commands(self, extra_args, section='testenv'):
+        """Get commands to run from the config file.
+
+        If any of the commands contain the string '{posargs}', then this
+        is replaced with the extra_args value.
+        """
         ini = self._open_tox_ini()
-        commands = ini.get(section, 'commands')
+        commands = ini.get(section, 'commands').split("\n")
         extra_args = " ".join(extra_args)
-        if '{posargs}' in commands:
-            commands = commands.replace('{posargs}', extra_args)
-        else:
-            commands += " "
-            commands += extra_args
-        return commands
+
+        scrubbed = []
+        for cmd in commands:
+            if '{posargs}' in cmd:
+                scrubbed.append(cmd.replace('{posargs}', extra_args))
+            else:
+                scrubbed.append(cmd)
+        return scrubbed
 
     def get_prep_commands(self):
         ini = self._open_tox_ini()

dox/tests/config/test_commands.py

@@ -39,20 +39,20 @@ class TestCommands(base.TestCase):
     scenarios = [
         ('dox_yaml', dict(
             dox_yaml=True, tox_ini=False, travis_yaml=False,
-            dox_value="testr run", tox_value=None, travis_value=None,
+            dox_value=["testr run"], tox_value=None, travis_value=None,
             commands="testr run")),
         ('dox_yaml_ignore_others', dict(
             dox_yaml=True, tox_ini=True, travis_yaml=True,
-            dox_value="testr run", tox_value="setup.py test",
-            travis_value="gem test",
+            dox_value=["testr run"], tox_value=["setup.py test"],
+            travis_value=["gem test"],
             commands="testr run")),
         ('tox_ini', dict(
             dox_yaml=False, tox_ini=True, travis_yaml=False,
-            dox_value=None, tox_value="setup.py test", travis_value=None,
+            dox_value=None, tox_value=["setup.py test"], travis_value=None,
             commands="setup.py test")),
         ('travis_yaml', dict(
             dox_yaml=False, tox_ini=False, travis_yaml=True,
-            dox_value="testr run", tox_value=None, travis_value="ruby",
+            dox_value=["testr run"], tox_value=None, travis_value=["ruby"],
             commands="ruby")),
     ]
 

dox/tests/config/test_tox_ini.py

@@ -51,10 +51,7 @@ class TestToxIni(base.TestCase):
                          self.toxini.get_images())
 
     def test_get_commands(self):
-        self.assertEqual('foobar -c',
-                         self.toxini.get_commands(['-c']))
-
-        self.assertEqual('foobar -c blah',
+        self.assertEqual(['foobar -c blah'],
                          self.toxini.get_commands(
                              ['-c'], section='testenv2'))