Changeset 7093 for main/waeup.sirp/trunk

Timestamp:

12 Nov 2011, 07:32:42 (13 years ago)

Author:

uli

Message:

Implement deleteFile() and deleteFileByContext() for ExtFileStore?. We
can now also remove files from ExtFileStores?.

File:

• main/waeup.sirp/trunk/src/waeup/sirp/imagestorage.py (modified) (3 diffs)

main/waeup.sirp/trunk/src/waeup/sirp/imagestorage.py

@@ -314 +314 @@
         return
 
-    def getFile(self, file_id):
-        """Get a file stored under file ID `file_id`.
-
-        Returns a file already opened for reading.
-
-        If the file cannot be found ``None`` is returned.
-
-        This methods takes into account registered handlers for any
-        marker put into the file_id.
-
-        .. seealso:: :class:`DefaultFileStoreHandler`
+    def _pathFromFileID(self, file_id):
+        """Helper method to create filesystem path from FileID.
+
+        Used class-internally. Do not rely on this method when working
+        with an :class:`ExtFileStore` instance from other components.
         """
         marker, filename, base, ext = self.extractMarker(file_id)
@@ -330 +324 @@
                                default=DefaultFileStoreHandler())
         path = handler.pathFromFileID(self, self.root, file_id)
+        return path
+
+    def getFile(self, file_id):
+        """Get a file stored under file ID `file_id`.
+
+        Returns a file already opened for reading.
+
+        If the file cannot be found ``None`` is returned.
+
+        This methods takes into account registered handlers for any
+        marker put into the file_id.
+
+        .. seealso:: :class:`DefaultFileStoreHandler`
+        """
+        path = self._pathFromFileID(file_id)
         if not os.path.exists(path):
             return None
@@ -357 +366 @@
         file_id = IFileStoreNameChooser(context).chooseName(attr=attr)
         return self.getFile(file_id)
+
+    def deleteFile(self, file_id):
+        """Delete file stored under `file_id` in storage.
+
+        The file is physically removed from filesystem.
+        """
+        path = self._pathFromFileID(file_id)
+        if not os.path.exists(path) or not os.path.isfile(path):
+            return
+        os.unlink(path)
+        return
+
+    def deleteFileByContext(self, context, attr=None):
+        """Remove file identified by `context` and `attr` if it exists.
+
+        This method takes into account registered handlers and file
+        name choosers for context types to build an intermediate file
+        id for the context and `attr` given.
+
+        Both, `context` and `attr` are used to find (`context`)
+        and feed (`attr`) an appropriate file name chooser.
+
+        This is a convenience method that internally calls
+        :meth:`getFile`.
+
+        .. seealso:: :class:`FileStoreNameChooser`,
+                     :class:`DefaultFileStoreHandler`.
+
+        """
+        file_id = IFileStoreNameChooser(context).chooseName(attr=attr)
+        return self.deleteFile(file_id)
 
     def createFile(self, filename, f):