Support two different versions of magic

The API for magic has changed at some point.  Debian and Ubuntu still
have an old version, but only the new version can be installed via pip.
This commit allows us to use either version.

1 files changed, 8 insertions, 3 deletions

diff --git a/alot/helper.py b/alot/helper.py
index 7f288a4d..9eede32d 100644
--- a/alot/helper.py
+++ b/alot/helper.py
@@ -391,9 +391,14 @@ def guess_encoding(blob):
     :returns: encoding
     :rtype: str
     """
-    m = magic.open(magic.MAGIC_MIME_ENCODING)
-    m.load()
-    return m.buffer(blob)
+    if hasattr(magic, 'open'):
+        m = magic.open(magic.MAGIC_MIME_TYPE)
+        m.load()
+        return m.buffer(blob)
+    elif hasattr(magic, 'from_buffer'):
+        return magic.from_buffer(blob, mime=True)
+    else:
+        raise Exception('Unknown magic API')
 
 
 # TODO: make this work on blobs, not paths