put format-specific db writers/readers together

1 files changed, 35 insertions, 0 deletions

diff --git a/vk/utils/tracking/db/format.py b/vk/utils/tracking/db/format.py
new file mode 100644
index 0000000..4856094
--- /dev/null
+++ b/vk/utils/tracking/db/format.py
@@ -0,0 +1,35 @@
+# Copyright 2016 Egor Tensin <Egor.Tensin@gmail.com>
+# This file is licensed under the terms of the MIT License.
+# See LICENSE.txt for details.
+
+from enum import Enum
+
+from .backend import *
+
+class Format(Enum):
+    CSV = 'csv'
+    LOG = 'log'
+    NULL = 'null'
+
+    def create_writer(self, fd):
+        if self is Format.CSV:
+            return csv.Writer(fd)
+        elif self is Format.LOG:
+            return log.Writer(fd)
+        elif self is Format.NULL:
+            return null.Writer(fd)
+        else:
+            raise NotImplementedError('unsupported database format: ' + str(self))
+
+    def create_reader(self, fd):
+        if self is Format.CSV:
+            return csv.Reader(fd)
+        elif self is Format.LOG:
+            raise NotImplementedError()
+        elif self is Format.NULL:
+            return null.Reader(fd)
+        else:
+            raise NotImplementedError('unsupported database format: ' + str(self))
+
+    def __str__(self):
+        return self.value