[sysadmin-bin] convert sets into lists when saving json

[Olav Vitters <ovitters src gnome org>]

commit 49153c9eed51a33314567a40a4b4358d5948f14a
Author: Olav Vitters <olav vitters nl>
Date:   Tue Jan 20 22:00:21 2015 +0100

    convert sets into lists when saving json

 ftpadmin |    9 ++++++++-
 1 files changed, 8 insertions(+), 1 deletions(-)
---
diff --git a/ftpadmin b/ftpadmin
index ee41307..f94c88e 100755
--- a/ftpadmin
+++ b/ftpadmin
@@ -255,6 +255,13 @@ if not hasattr(tarfile.TarFile, 'xzopen'):
     tarfile.open = XzTarFile.open
 
 
+class SetEncoder(json.JSONEncoder):
+    def default(self, obj):
+       if isinstance(obj, set):
+          return list(obj)
+       return json.JSONEncoder.default(self, obj)
+
+
 class BasicInfo(object):
     GROUPID = None
 
@@ -440,7 +447,7 @@ class DOAP(BasicInfo):
         if os.path.exists(self.jsonfile):
             os.remove(self.jsonfile)
         with open(self.jsonfile, 'w') as f:
-            json.dump((self.JSONVERSION, self.etag, self.last_modified, self.info, self.tarball_to_module, 
self.uid_to_module), f)
+            json.dump((self.JSONVERSION, self.etag, self.last_modified, self.info, self.tarball_to_module, 
self.uid_to_module), f, cls=SetEncoder)
             if self.GROUPID is not None:
                 os.fchown(f.fileno(), -1, self.GROUPID)