[4.0] Create new binary and define new entrypoints for subcommands

This is the first patch to add a new `sos` binary to act as the new
commandline interface for users.

It adds the basic `SoS()` and `SoSComponent()` classes that will be
built out and used going forward for new subcommand development. Actual
functionality will be added in coming patches, as this is mainly serving
as a checkpoint to avoid over-large commits affecting wide swathes of
changes at once.

Resolves: #1986

Signed-off-by: Jake Hunsaker <jhunsake@redhat.com>

2 files changed, 116 insertions, 14 deletions

diff --git a/bin/sos b/bin/sos
new file mode 100755
index 00000000..9b9592da
--- /dev/null
+++ b/bin/sos
@@ -0,0 +1,24 @@
+#!/usr/bin/python
+# This file is part of the sos project: https://github.com/sosreport/sos
+#
+# This copyrighted material is made available to anyone wishing to use,
+# modify, copy, or redistribute it subject to the terms and conditions of
+# version 2 of the GNU General Public License.
+#
+# See the LICENSE file in the source distribution for further information.
+
+import sys
+import os
+
+try:
+    sys.path.insert(0, os.getcwd())
+    from sos import SoS
+except KeyboardInterrupt:
+    raise SystemExit()
+
+
+if __name__ == '__main__':
+    sos = SoS(sys.argv[1:])
+    sos.execute()
+
+# vim:ts=4 et sw=4
diff --git a/sos/__init__.py b/sos/__init__.py
index 111e066e..9da2c107 100644
--- a/sos/__init__.py
+++ b/sos/__init__.py
@@ -14,8 +14,8 @@
 This module houses the i18n setup and message function. The default is to use
 gettext to internationalize messages.
 """
+__version__ = "3.9"
 
-import gettext
 import six
 
 from argparse import ArgumentParser
@@ -25,19 +25,7 @@ if six.PY3:
 else:
     from ConfigParser import ConfigParser, ParsingError, Error
 
-__version__ = "3.9"
-
-gettext_dir = "/usr/share/locale"
-gettext_app = "sos"
-
-gettext.bindtextdomain(gettext_app, gettext_dir)
-
-
-def _default(msg):
-    return gettext.dgettext(gettext_app, msg)
-
-
-_sos = _default
+from sos.report import SoSReport
 
 # Global option definitions
 # These must be in the module itself in order to be available to both
@@ -360,4 +348,94 @@ class SoSOptions(object):
         opt_items = sorted(self.dict().items(), key=lambda x: x[0])
         return [argify(n, v) for (n, v) in opt_items if filter_opt(n, v)]
 
+
+class SoSComponent():
+    """Any sub-command that sos supports needs to subclass SoSComponent in
+    order to be properly supported by the sos binary.
+
+    This class contains the standardized entrypoint for subcommands, as well as
+    building out supported options from both globally shared option lists, and
+    options supported by that specific subcommand.
+
+    When sos initializes, it will load an unintialized instance of each class
+    found within one recursion of the module root directory that subclasses
+    SoSComponent.
+
+    If sos is able to match the user-specified subcommand to one that exists
+    locally, then that SoSComponent is initialized, logging is setup, and a
+    policy is loaded. From there, the component's execute() method takes over.
+
+    Added in 4.0
+    """
+
+    def __init__(self, parser, parsed_args, cmdline_args):
+        self.parser = parser
+        self.args = parsed_args
+        self.cmdline = cmdline_args
+
+class SoS():
+    """Main entrypoint for sos from the command line
+
+    Upon intialization, this class loads the basic option parser which will
+    include the options shared by support components/subcommands. This is also
+    where all subcommands present in the local installation are discovered,
+    loaded, and if a matching one is found, intialized.
+    """
+
+    def __init__(self, args):
+        self.cmdline = args
+        usage_string = "%(prog)s component [options]\n\n"
+        # define the local subcommands that exist on the system
+        self._components = {'report': SoSReport}
+        # build the top-level parser
+        self.parser = ArgumentParser(usage=usage_string)
+        self.parser.register('action', 'extend', SoSListOption)
+        # set the component subparsers
+        self.subparsers = self.parser.add_subparsers(
+            dest='component',
+            help='sos component to run'
+        )
+        self.subparsers.required = True
+        # now build the parser for each component.
+        # this needs to be done here, as otherwise --help will be unavailable
+        # for the component subparsers
+        for comp in self._components:
+            _com_subparser = self.subparsers.add_parser(comp)
+            _com_subparser.register('action', 'extend', SoSListOption)
+            self._add_common_options(_com_subparser)
+            self._components[comp].add_parser_options(_com_subparser)
+        self.args = self.parser.parse_args()
+        self._init_component()
+
+    def _add_common_options(self, parser):
+        """Adds the options shared across components to the parser
+        """
+        parser.add_argument("-q", "--quiet", action="store_true",
+                            dest="quiet", default=False,
+                            help="only print fatal errors")
+        parser.add_argument("-s", "--sysroot", action="store", dest="sysroot",
+                            help="system root directory path (default='/')",
+                            default=None)
+        parser.add_argument("--tmp-dir", action="store",
+                            dest="tmp_dir",
+                            help="specify alternate temporary directory",
+                            default=None)
+        parser.add_argument("-v", "--verbose", action="count",
+                            dest="verbosity", default=0,
+                            help="increase verbosity")
+
+    def _init_component(self):
+        """Determine which component has been requested by the user, and then
+        initialize that component.
+        """
+        _com = self.args.component
+        if not _com in self._components.keys():
+            print("Unknown subcommand '%s' specified" % _com)
+        try:
+            self._component = self._components[_com](self.parser, self.args,
+                                                     self.cmdline)
+        except Exception as err:
+            print("Could not initialize '%s': %s" % (_com, err))
+            sys.exit(1)
+
 # vim: set et ts=4 sw=4 :