#51 - reuses dbm instances between TagIndex instances if the dbm instances are using the same file

3 files changed, 13 insertions, 13 deletions

diff --git a/service/pixelated/adapter/tag_index.py b/service/pixelated/adapter/tag_index.py
index 3cdeb1d8..357f7513 100644
--- a/service/pixelated/adapter/tag_index.py
+++ b/service/pixelated/adapter/tag_index.py
@@ -24,14 +24,17 @@ class TagIndex:
     Manages an index for mail's tags using a file storage.
     """
 
+    __db_instances = dict()
+
     def __init__(self, db_path):
         self.db_path = db_path
-        self.db = dbm.open(db_path, 'c')
-        atexit.register(self.close_db)
+        if db_path not in TagIndex.__db_instances:
+            TagIndex.__db_instances[db_path] = dbm.open(db_path, 'c')
+        self.db = TagIndex.__db_instances[db_path]
+        atexit.register(self._close_db)
 
     def set(self, tag):
         self.db[tag.name] = tag.as_json_string()
-        self._flush()
 
     def add(self, tag):
         if tag.name not in self.db:
@@ -46,7 +49,6 @@ class TagIndex:
     def remove(self, tag_name):
         if tag_name in self.db:
             del self.db[tag_name]
-            self._flush()
 
     def empty(self):
         return len(self.db.keys()) == 0
@@ -54,9 +56,7 @@ class TagIndex:
     def values(self):
         return set(self.get(key) for key in self.db.keys())
 
-    def close_db(self):
+    def _close_db(self):
         self.db.close()
-
-    def _flush(self):
-        self.close_db()
-        self.db = dbm.open(self.db_path, 'c')
+        if self.db_path in TagIndex.__db_instances:
+            del TagIndex.__db_instances[self.db_path]
diff --git a/service/test/adapter/pixelated_mailbox_test.py b/service/test/adapter/pixelated_mailbox_test.py
index 7e8e9d3c..72e6141d 100644
--- a/service/test/adapter/pixelated_mailbox_test.py
+++ b/service/test/adapter/pixelated_mailbox_test.py
@@ -28,6 +28,7 @@ class TestPixelatedMailbox(unittest.TestCase):
         self.db_file_path = '/tmp/test_tags'
 
     def tearDown(self):
+        TagIndex(self.db_file_path)._close_db()
         os.remove(self.db_file_path + '.db')
 
     def test_special_tags_always_exists(self):
@@ -38,7 +39,6 @@ class TestPixelatedMailbox(unittest.TestCase):
         tag_index = TagIndex(self.db_file_path)
         tag_index.set(Tag('one_tag'))
         tag_index.set(Tag('two_tag'))
-        tag_index.close_db()
         mailbox = PixelatedMailbox(test_helper.leap_mailbox(), self.db_file_path)
         expected_tags = set([Tag('one_tag'), Tag('two_tag')]).union(mailbox.SPECIAL_TAGS)
         self.assertEquals(expected_tags, mailbox.all_tags())
@@ -48,7 +48,6 @@ class TestPixelatedMailbox(unittest.TestCase):
         tag = Tag('one_tag')
         tag.increment(12)
         tag_index.set(tag)
-        tag_index.close_db()
         mailbox = PixelatedMailbox(test_helper.leap_mailbox(), self.db_file_path)
         self.assertEquals(0, mailbox.tag_index.get('inbox').total)
         self.assertEquals(1, mailbox.tag_index.get('one_tag').total)
diff --git a/service/test/adapter/tag_index_test.py b/service/test/adapter/tag_index_test.py
index 515c9571..21564fc5 100644
--- a/service/test/adapter/tag_index_test.py
+++ b/service/test/adapter/tag_index_test.py
@@ -16,6 +16,7 @@
 # along with Pixelated. If not, see <http://www.gnu.org/licenses/>.
 import unittest
 import os
+import uuid
 
 from pixelated.adapter.tag_index import TagIndex
 from pixelated.adapter.tag import Tag
@@ -24,11 +25,11 @@ from pixelated.adapter.tag import Tag
 class TestTagIndex(unittest.TestCase):
 
     def setUp(self):
-        self.db_path = '/tmp/database_test_tag_index'
+        self.db_path = '/tmp/test_tag_index_' + str(uuid.uuid4())
         self.tag_index = TagIndex(self.db_path)
 
     def tearDown(self):
-        self.tag_index.close_db()
+        self.tag_index._close_db()
         os.remove(self.db_path + '.db')
 
     def test_get_and_set_works(self):