New "borgmatic" command to support Borg backup software, a fork of Attic.

atticmatic/backends/attic.py

@@ -0,0 +1,12 @@
+from functools import partial
+
+from atticmatic.backends import shared
+
+# An atticmatic backend that supports Attic for actually handling backups.
+
+COMMAND = 'attic'
+
+
+create_archive = partial(shared.create_archive, command=COMMAND)
+prune_archives = partial(shared.prune_archives, command=COMMAND)
+check_archives = partial(shared.check_archives, command=COMMAND)

atticmatic/backends/borg.py

@@ -0,0 +1,13 @@
+from functools import partial
+
+from atticmatic.backends import shared
+
+# An atticmatic backend that supports Borg for actually handling backups.
+
+COMMAND = 'borg'
+
+
+create_archive = partial(shared.create_archive, command=COMMAND)
+prune_archives = partial(shared.prune_archives, command=COMMAND)
+check_archives = partial(shared.check_archives, command=COMMAND)
+

atticmatic/backends/shared.py

@@ -6,10 +6,16 @@ import subprocess
 from atticmatic.verbosity import VERBOSITY_SOME, VERBOSITY_LOTS
 
 
-def create_archive(excludes_filename, verbosity, source_directories, repository):
+# Common backend functionality shared by Attic and Borg. As the two backup
+# commands diverge, these shared functions will likely need to be replaced
+# with non-shared functions within atticmatic.backends.attic and
+# atticmatic.backends.borg.
+
+
+def create_archive(excludes_filename, verbosity, source_directories, repository, command):
     '''
-    Given an excludes filename, a vebosity flag, a space-separated list of source directories, and
-    a local or remote repository path, create an attic archive.
+    Given an excludes filename, a vebosity flag, a space-separated list of source directories, a
+    local or remote repository path, and a command to run, create an attic archive.
     '''
     sources = tuple(source_directories.split(' '))
     verbosity_flags = {
@@ -17,8 +23,8 @@ def create_archive(excludes_filename, verbosity, source_directories, repository)
         VERBOSITY_LOTS: ('--verbose', '--stats'),
     }.get(verbosity, ())
 
-    command = (
-        'attic', 'create',
+    full_command = (
+        command, 'create',
         '--exclude-from', excludes_filename,
         '{repo}::{hostname}-{timestamp}'.format(
             repo=repository,
@@ -27,7 +33,7 @@ def create_archive(excludes_filename, verbosity, source_directories, repository)
         ),
     ) + sources + verbosity_flags
 
-    subprocess.check_call(command)
+    subprocess.check_call(full_command)
 
 
 def _make_prune_flags(retention_config):
@@ -52,18 +58,19 @@ def _make_prune_flags(retention_config):
     )
 
 
-def prune_archives(verbosity, repository, retention_config):
+def prune_archives(verbosity, repository, retention_config, command):
     '''
-    Given a verbosity flag, a local or remote repository path, and a retention config dict, prune
-    attic archives according the the retention policy specified in that configuration.
+    Given a verbosity flag, a local or remote repository path, a retention config dict, and a
+    command to run, prune attic archives according the the retention policy specified in that
+    configuration.
     '''
     verbosity_flags = {
         VERBOSITY_SOME: ('--stats',),
         VERBOSITY_LOTS: ('--verbose', '--stats'),
     }.get(verbosity, ())
 
-    command = (
-        'attic', 'prune',
+    full_command = (
+        command, 'prune',
         repository,
     ) + tuple(
         element
@@ -71,7 +78,7 @@ def prune_archives(verbosity, repository, retention_config):
         for element in pair
     ) + verbosity_flags
 
-    subprocess.check_call(command)
+    subprocess.check_call(full_command)
 
 
 DEFAULT_CHECKS = ('repository', 'archives')
@@ -123,10 +130,10 @@ def _make_check_flags(checks):
     )
 
 
-def check_archives(verbosity, repository, consistency_config):
+def check_archives(verbosity, repository, consistency_config, command):
     '''
-    Given a verbosity flag, a local or remote repository path, and a consistency config dict, check
-    the contained attic archives for consistency.
+    Given a verbosity flag, a local or remote repository path, a consistency config dict, and a
+    command to run, check the contained attic archives for consistency.
 
     If there are no consistency checks to run, skip running them.
     '''
@@ -139,12 +146,12 @@ def check_archives(verbosity, repository, consistency_config):
         VERBOSITY_LOTS: ('--verbose',),
     }.get(verbosity, ())
 
-    command = (
-        'attic', 'check',
+    full_command = (
+        command, 'check',
         repository,
     ) + _make_check_flags(checks) + verbosity_flags
 
-    # Attic's check command spews to stdout even without the verbose flag. Suppress it.
+    # The check command spews to stdout even without the verbose flag. Suppress it.
     stdout = None if verbosity_flags else open(os.devnull, 'w')
 
-    subprocess.check_call(command, stdout=stdout)
+    subprocess.check_call(full_command, stdout=stdout)

atticmatic/command.py

@@ -1,31 +1,34 @@
 from __future__ import print_function
 from argparse import ArgumentParser
+from importlib import import_module
+import os
 from subprocess import CalledProcessError
 import sys
 
-from atticmatic.attic import check_archives, create_archive, prune_archives
 from atticmatic.config import parse_configuration
 
 
-DEFAULT_CONFIG_FILENAME = '/etc/atticmatic/config'
-DEFAULT_EXCLUDES_FILENAME = '/etc/atticmatic/excludes'
+DEFAULT_CONFIG_FILENAME_PATTERN = '/etc/{}/config'
+DEFAULT_EXCLUDES_FILENAME_PATTERN = '/etc/{}/excludes'
 
 
-def parse_arguments(*arguments):
+def parse_arguments(command_name, *arguments):
     '''
-    Parse the given command-line arguments and return them as an ArgumentParser instance.
+    Given the name of the command with which this script was invoked and command-line arguments,
+    parse the arguments and return them as an ArgumentParser instance. Use the command name to
+    determine the default configuration and excludes paths.
     '''
     parser = ArgumentParser()
     parser.add_argument(
         '-c', '--config',
         dest='config_filename',
-        default=DEFAULT_CONFIG_FILENAME,
+        default=DEFAULT_CONFIG_FILENAME_PATTERN.format(command_name),
         help='Configuration filename',
     )
     parser.add_argument(
         '--excludes',
         dest='excludes_filename',
-        default=DEFAULT_EXCLUDES_FILENAME,
+        default=DEFAULT_EXCLUDES_FILENAME_PATTERN.format(command_name),
         help='Excludes filename',
     )
     parser.add_argument(
@@ -37,15 +40,30 @@ def parse_arguments(*arguments):
     return parser.parse_args(arguments)
 
 
+def load_backend(command_name):
+    '''
+    Given the name of the command with which this script was invoked, return the corresponding
+    backend module responsible for actually dealing with backups.
+    '''
+    backend_name = {
+        'atticmatic': 'attic',
+        'borgmatic': 'borg',
+    }.get(command_name, 'attic')
+
+    return import_module('atticmatic.backends.{}'.format(backend_name))
+
+
 def main():
     try:
-        args = parse_arguments(*sys.argv[1:])
+        command_name = os.path.basename(sys.argv[0])
+        args = parse_arguments(command_name, *sys.argv[1:])
         config = parse_configuration(args.config_filename)
         repository = config.location['repository']
+        backend = load_backend(command_name)
 
-        create_archive(args.excludes_filename, args.verbosity, **config.location)
-        prune_archives(args.verbosity, repository, config.retention)
-        check_archives(args.verbosity, repository, config.consistency)
+        backend.create_archive(args.excludes_filename, args.verbosity, **config.location)
+        backend.prune_archives(args.verbosity, repository, config.retention)
+        backend.check_archives(args.verbosity, repository, config.consistency)
     except (ValueError, IOError, CalledProcessError) as error:
         print(error, file=sys.stderr)
         sys.exit(1)

atticmatic/tests/integration/test_command.py

@@ -5,16 +5,19 @@ from nose.tools import assert_raises
 from atticmatic import command as module
 
 
-def test_parse_arguments_with_no_arguments_uses_defaults():
-    parser = module.parse_arguments()
+COMMAND_NAME = 'foomatic'
 
-    assert parser.config_filename == module.DEFAULT_CONFIG_FILENAME
-    assert parser.excludes_filename == module.DEFAULT_EXCLUDES_FILENAME
+
+def test_parse_arguments_with_no_arguments_uses_defaults():
+    parser = module.parse_arguments(COMMAND_NAME)
+
+    assert parser.config_filename == module.DEFAULT_CONFIG_FILENAME_PATTERN.format(COMMAND_NAME)
+    assert parser.excludes_filename == module.DEFAULT_EXCLUDES_FILENAME_PATTERN.format(COMMAND_NAME)
     assert parser.verbosity == None
 
 
 def test_parse_arguments_with_filename_arguments_overrides_defaults():
-    parser = module.parse_arguments('--config', 'myconfig', '--excludes', 'myexcludes')
+    parser = module.parse_arguments(COMMAND_NAME, '--config', 'myconfig', '--excludes', 'myexcludes')
 
     assert parser.config_filename == 'myconfig'
     assert parser.excludes_filename == 'myexcludes'
@@ -22,10 +25,10 @@ def test_parse_arguments_with_filename_arguments_overrides_defaults():
 
 
 def test_parse_arguments_with_verbosity_flag_overrides_default():
-    parser = module.parse_arguments('--verbosity', '1')
+    parser = module.parse_arguments(COMMAND_NAME, '--verbosity', '1')
 
-    assert parser.config_filename == module.DEFAULT_CONFIG_FILENAME
-    assert parser.excludes_filename == module.DEFAULT_EXCLUDES_FILENAME
+    assert parser.config_filename == module.DEFAULT_CONFIG_FILENAME_PATTERN.format(COMMAND_NAME)
+    assert parser.excludes_filename == module.DEFAULT_EXCLUDES_FILENAME_PATTERN.format(COMMAND_NAME)
     assert parser.verbosity == 1
 
 
@@ -35,6 +38,6 @@ def test_parse_arguments_with_invalid_arguments_exits():
 
     try:
         with assert_raises(SystemExit):
-            module.parse_arguments('--posix-me-harder')
+            module.parse_arguments(COMMAND_NAME, '--posix-me-harder')
     finally:
         sys.stderr = original_stderr

atticmatic/tests/unit/backends/test_shared.py

@@ -2,7 +2,7 @@ from collections import OrderedDict
 
 from flexmock import flexmock
 
-from atticmatic import attic as module
+from atticmatic.backends import shared as module
 from atticmatic.tests.builtins import builtins_mock
 from atticmatic.verbosity import VERBOSITY_SOME, VERBOSITY_LOTS
 
@@ -42,6 +42,7 @@ def test_create_archive_should_call_attic_with_parameters():
         verbosity=None,
         source_directories='foo bar',
         repository='repo',
+        command='attic',
     )
 
 
@@ -55,6 +56,7 @@ def test_create_archive_with_verbosity_some_should_call_attic_with_stats_paramet
         verbosity=VERBOSITY_SOME,
         source_directories='foo bar',
         repository='repo',
+        command='attic',
     )
 
 
@@ -68,6 +70,7 @@ def test_create_archive_with_verbosity_lots_should_call_attic_with_verbose_param
         verbosity=VERBOSITY_LOTS,
         source_directories='foo bar',
         repository='repo',
+        command='attic',
     )
 
 
@@ -108,6 +111,7 @@ def test_prune_archives_should_call_attic_with_parameters():
         verbosity=None,
         repository='repo',
         retention_config=retention_config,
+        command='attic',
     )
 
 
@@ -122,6 +126,7 @@ def test_prune_archives_with_verbosity_some_should_call_attic_with_stats_paramet
         repository='repo',
         verbosity=VERBOSITY_SOME,
         retention_config=retention_config,
+        command='attic',
     )
 
 
@@ -136,6 +141,7 @@ def test_prune_archives_with_verbosity_lots_should_call_attic_with_verbose_param
         repository='repo',
         verbosity=VERBOSITY_LOTS,
         retention_config=retention_config,
+        command='attic',
     )
 
 
@@ -193,6 +199,7 @@ def test_check_archives_should_call_attic_with_parameters():
         verbosity=None,
         repository='repo',
         consistency_config=consistency_config,
+        command='attic',
     )
 
 
@@ -211,6 +218,7 @@ def test_check_archives_with_verbosity_some_should_call_attic_with_verbose_param
         verbosity=VERBOSITY_SOME,
         repository='repo',
         consistency_config=consistency_config,
+        command='attic',
     )
 
 
@@ -229,6 +237,7 @@ def test_check_archives_with_verbosity_lots_should_call_attic_with_verbose_param
         verbosity=VERBOSITY_LOTS,
         repository='repo',
         consistency_config=consistency_config,
+        command='attic',
     )
 
 
@@ -241,4 +250,5 @@ def test_check_archives_without_any_checks_should_bail():
         verbosity=None,
         repository='repo',
         consistency_config=consistency_config,
+        command='attic',
     )

atticmatic/tests/unit/test_command.py

@@ -0,0 +1,33 @@
+from flexmock import flexmock
+
+from atticmatic import command as module
+
+
+def test_load_backend_with_atticmatic_command_should_return_attic_backend():
+    backend = flexmock()
+    (
+        flexmock(module).should_receive('import_module').with_args('atticmatic.backends.attic')
+        .and_return(backend).once()
+    )
+
+    assert module.load_backend('atticmatic') == backend
+
+
+def test_load_backend_with_unknown_command_should_return_attic_backend():
+    backend = flexmock()
+    (
+        flexmock(module).should_receive('import_module').with_args('atticmatic.backends.attic')
+        .and_return(backend).once()
+    )
+
+    assert module.load_backend('unknownmatic') == backend
+
+
+def test_load_backend_with_borgmatic_command_should_return_borg_backend():
+    backend = flexmock()
+    (
+        flexmock(module).should_receive('import_module').with_args('atticmatic.backends.borg')
+        .and_return(backend).once()
+    )
+
+    assert module.load_backend('borgmatic') == backend