new module: combox/silo.py

- Contains the ComboxSilo class which provides an interface to access
  the db that stores information about files in the combox directory.

Tests for this module is at tests/silo_test.py

2 files changed, 186 insertions, 0 deletions

diff --git a/combox/silo.py b/combox/silo.py
new file mode 100644
index 0000000..cbb2065
--- /dev/null
+++ b/combox/silo.py
@@ -0,0 +1,99 @@
+#    Copyright (C) 2015 Combox author(s). See AUTHORS.
+#
+#    This file is part of Combox.
+#
+#   Combox is free software: you can redistribute it and/or modify it
+#   under the terms of the GNU General Public License as published by
+#   the Free Software Foundation, either version 3 of the License, or
+#   (at your option) any later version.
+#
+#   Combox is distributed in the hope that it will be useful, but
+#   WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+#   General Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License
+#   along with Combox (see COPYING).  If not, see
+#   <http://www.gnu.org/licenses/>.
+
+import pickledb
+
+from os import path
+
+from combox.file import hash_file
+
+class ComboxSilo(object):
+    """The Combox silo.
+
+    Helps keep track of files in combox directory.
+    """
+
+
+    def __init__(self, config):
+        """config: a dictinary which contains combox configuration.
+
+        """
+        self.config = config
+
+        silo = path.join(config['silo_dir'], 'silo.db')
+        self.db = pickledb.load(silo, True)
+
+
+    def update(self, filep):
+        """Update filep's info in db
+
+        filep and the hash of its content is written to the db.
+
+        filep: path to the file in combox directory.
+
+        """
+
+        fhash = hash_file(filep)
+
+        return self.db.set(filep, fhash)
+
+
+    def remove(self, filep):
+        """Removes filep from db.
+
+        filep: path to the file in combox directory.
+
+        """
+
+        return self.db.rem(filep)
+
+
+    def exists(self, filep):
+        """Checks if filep's info is stored in db.
+
+        Returns True if filep's info is in db; False otherwise.
+
+        filep: path to the file in combox directory.
+
+        """
+
+        if self.db.get(filep) is None:
+            return False
+        else:
+            return True
+
+
+    def stale(self, filep):
+        """Returns True if filep's hash is different from the hash stored in db.
+
+        Returns None, if filep's info is not yet stored in db.
+        Returns False, if filep's hash has not changed it.
+
+        filep: path to the file in combox directory.
+
+        """
+
+        fhash = hash_file(filep)
+        fhash_in_db = self.db.get(filep)
+
+        if fhash_in_db is None:
+            return None
+        elif fhash == fhash_in_db:
+            return False
+        else:
+            return True
diff --git a/tests/silo_test.py b/tests/silo_test.py
new file mode 100644
index 0000000..0f1558f
--- /dev/null
+++ b/tests/silo_test.py
@@ -0,0 +1,87 @@
+#    Copyright (C) 2015 Combox author(s). See AUTHORS.
+#
+#    This file is part of Combox.
+#
+#   Combox is free software: you can redistribute it and/or modify it
+#   under the terms of the GNU General Public License as published by
+#   the Free Software Foundation, either version 3 of the License, or
+#   (at your option) any later version.
+#
+#   Combox is distributed in the hope that it will be useful, but
+#   WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+#   General Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License
+#   along with Combox (see COPYING).  If not, see
+#   <http://www.gnu.org/licenses/>.
+
+import yaml
+
+from shutil import copyfile
+from os import path, remove
+
+from combox.silo import ComboxSilo
+from combox.file import read_file, write_file
+
+CONFIG_DIR = path.join('tests', 'test-config')
+
+config_file = path.join(CONFIG_DIR, 'config.yaml')
+try:
+    config = yaml.load(file(config_file, 'r'))
+except yaml.YAMLError, exc:
+    raise AssertionError("Error in configuration file:", exc)
+
+
+FILES_DIR = path.abspath(config['combox_dir'])
+LOREM = path.join(FILES_DIR,'lorem.txt')
+LOREM_IPSUM = path.join(FILES_DIR,'lorem-ipsum.txt')
+IPSUM = path.join(FILES_DIR,'ipsum.txt')
+
+
+def test_csilo():
+    """
+    Tests the ComboxSilo class.
+    """
+    csilo = ComboxSilo(config)
+
+
+    # Test - update
+    csilo.update(LOREM)
+    lorem_content = read_file(LOREM)
+    lorem_hash = csilo.db.get(LOREM)
+    assert lorem_hash
+
+    csilo.update(IPSUM)
+    ispum_content = read_file(IPSUM)
+    ipsum_hash = csilo.db.get(IPSUM)
+    assert ipsum_hash
+
+    lorem_ipsum_content = "%s\n%s" % (LOREM, IPSUM)
+    write_file(LOREM_IPSUM, lorem_ipsum_content)
+
+    csilo.update(LOREM_IPSUM)
+    lorem_ipsum_hash = csilo.db.get(LOREM_IPSUM)
+    assert lorem_ipsum_hash
+
+    assert lorem_ipsum_hash != lorem_hash
+    assert lorem_ipsum_hash != ipsum_hash
+
+    # Test - stale
+    lorem_ipsum_content = "%s\n%s" % (lorem_ipsum_content, IPSUM)
+    write_file(LOREM_IPSUM, lorem_ipsum_content)
+
+    assert csilo.stale(LOREM_IPSUM)
+    csilo.update(LOREM_IPSUM)
+    assert csilo.stale(LOREM_IPSUM) is False
+
+    lorem_ipsum_hash_new = csilo.db.get(LOREM_IPSUM)
+    assert lorem_ipsum_hash_new
+    assert lorem_ipsum_hash_new != lorem_ipsum_hash
+
+    # Test - remove
+    remove(LOREM_IPSUM)
+    csilo.remove(LOREM_IPSUM)
+
+    # Test - exists
+    assert not csilo.exists(LOREM_IPSUM)