Add filesystem storage

vdirsyncer/exceptions.py

@@ -0,0 +1,8 @@
+class Error(Exception):
+    pass
+
+class AlreadyExistingError(Error):
+    pass
+
+class WrongEtagError(Error):
+    pass

vdirsyncer/storage/base.py

@@ -1,4 +1,21 @@
-class Syncer(object):
+class Item(object):
+    '''wrapper class for VCALENDAR and VCARD'''
+    def __init__(self, raw):
+        self.raw = raw
+        self._uid = None
+
+    @property
+    def uid(self):
+        for line in raw.splitlines():
+            if line.startswith(b'UID'):
+                return line.lstrip(b'UID:').strip()
+
+
+class Storage(object):
+    def __init__(self, fileext, item_class=Item):
+        self.fileext = fileext
+        self.item_class = item_class
+
     def list_items(self):
         '''
         :returns: list of (href, etag)
@@ -15,12 +32,14 @@ class Syncer(object):
     def item_exists(self, href):
         '''
         check if item exists
+        :returns: True or False
         '''
         raise NotImplementedError()
 
     def upload(self, obj):
         '''
-        Upload a new object, raise error if it already exists.
+        Upload a new object, raise
+        :exc:`vdirsyncer.exceptions.AlreadyExistingError` if it already exists.
         :returns: (href, etag)
         '''
         raise NotImplementedError()

vdirsyncer/storage/filesystem.py

@@ -0,0 +1,50 @@
+import os
+from vdirsyncer.storage.base import Storage, Item
+from vdirsyncer.exceptions import AlreadyExistingError
+
+class FilesystemStorage(Storage):
+    def __init__(self, path, **kwargs):
+        self.path = path
+        super(FilesystemStorage, self).__init__(**kwargs)
+
+    def _get_etag(self, href):
+        return os.path.getmtime(href)
+
+    def _get_hrefs(self):
+        for fname in os.listdir(self.path):
+            href = os.path.join(self.path, fname)
+            if os.path.isfile(href):
+                yield href
+
+    def list_items(self):
+        for href in self._get_hrefs():
+            yield href, self._get_etag(href)
+
+    def get_items(self, hrefs):
+        for href in hrefs:
+            with open(href, 'rb') as f:
+                yield Item(f.read()), href, self._get_etag(href)
+
+    def item_exists(self, href):
+        return os.path.isfile(path)
+
+    def _get_href(self, obj):
+        return os.path.join(self.path, obj.uid + b'b' + self.fileext)
+
+    def upload(self, obj):
+        href = self._get_href(obj)
+        if os.path.exists(href):
+            raise AlreadyExistingError(href)
+        with open(href, 'wb+') as f:
+            f.write(obj.raw)
+        return href, self._get_etag(href)
+
+    def update(self, obj, etag):
+        href = self._get_href(obj)
+        actual_etag = self._get_etag(href)
+        if etag != actual_etag:
+            raise WrongEtagError(etag, actual_etag)
+
+        with open(href, 'wb') as f:
+            f.write(obj.raw)
+        return self._get_etag(href)