diff --git a/fdroidserver/checkupdates.py b/fdroidserver/checkupdates.py
index c57cd8be..a6b00130 100644
--- a/fdroidserver/checkupdates.py
+++ b/fdroidserver/checkupdates.py
@@ -505,7 +505,8 @@ def checkupdates_app(app, first=True):
 
     if commitmsg:
         metadatapath = os.path.join('metadata', app['id'] + '.txt')
-        metadata.write_metadata(metadatapath, app)
+        with open(metadatapath, 'w') as f:
+            metadata.write_metadata(f, app)
         if options.commit:
             logging.info("Commiting update for " + metadatapath)
             gitcmd = ["git", "commit", "-m", commitmsg]
diff --git a/fdroidserver/import.py b/fdroidserver/import.py
index ce19bd54..9841c7a1 100644
--- a/fdroidserver/import.py
+++ b/fdroidserver/import.py
@@ -248,7 +248,8 @@ def main():
         f.write(app['Repo Type'] + ' ' + app['Repo'])
 
     metadatapath = os.path.join('metadata', package + '.txt')
-    metadata.write_metadata(metadatapath, app)
+    with open(metadatapath, 'w') as f:
+        metadata.write_metadata(f, app)
     logging.info("Wrote " + metadatapath)
 
 
diff --git a/fdroidserver/metadata.py b/fdroidserver/metadata.py
index e5ae6716..530f1350 100644
--- a/fdroidserver/metadata.py
+++ b/fdroidserver/metadata.py
@@ -1040,9 +1040,9 @@ def parse_txt_metadata(apps, metadatapath):
 
 # Write a metadata file.
 #
-# 'dest'    - The path to the output file
+# 'mf'      - Writer interface (file, StringIO, ...)
 # 'app'     - The app data
-def write_metadata(dest, app):
+def write_metadata(mf, app):
 
     def writecomments(key):
         written = 0
@@ -1073,7 +1073,6 @@ def write_metadata(dest, app):
         if value:
             writefield(field, value)
 
-    mf = open(dest, 'w')
     writefield_nonempty('Disabled')
     if app['AntiFeatures']:
         writefield('AntiFeatures')
@@ -1161,4 +1160,3 @@ def write_metadata(dest, app):
         writefield('No Source Since')
         mf.write('\n')
     writecomments(None)
-    mf.close()
diff --git a/fdroidserver/rewritemeta.py b/fdroidserver/rewritemeta.py
index 47e478a4..ecf685be 100644
--- a/fdroidserver/rewritemeta.py
+++ b/fdroidserver/rewritemeta.py
@@ -18,7 +18,6 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-import os
 from argparse import ArgumentParser
 import logging
 import common
@@ -46,13 +45,14 @@ def main():
 
     for appid, app in apps.iteritems():
         metadatapath = app['metadatapath']
-        ext = os.path.splitext(metadatapath)[1][1:]
-        if ext == 'txt':
-            logging.debug("Rewriting " + metadatapath)
-            metadata.write_metadata(metadatapath, app)
-        else:
+        ext = common.get_extension(metadatapath)
+        if ext not in ['txt']:
             logging.info("Ignoring %s file at '%s'"
                          % (ext.upper(), metadatapath))
+            continue
+        logging.debug("Rewriting " + metadatapath)
+        with open(metadatapath, 'w') as f:
+            metadata.write_metadata(f, app)
 
     logging.debug("Finished.")