in JSON metadata, convert unicode to str to match the internal format

fdroidserver currently uses plain python 2.x strings rather than unicode
strings, so the parsed JSON should produce the same format as the parsed
.txt metadata.

fdroidserver/metadata.py

@@ -614,6 +614,36 @@ def post_metadata_parse(thisinfo):
 #
 
 
+def _decode_list(data):
+    '''convert items in a list from unicode to basestring'''
+    rv = []
+    for item in data:
+        if isinstance(item, unicode):
+            item = item.encode('utf-8')
+        elif isinstance(item, list):
+            item = _decode_list(item)
+        elif isinstance(item, dict):
+            item = _decode_dict(item)
+        rv.append(item)
+    return rv
+
+
+def _decode_dict(data):
+    '''convert items in a dict from unicode to basestring'''
+    rv = {}
+    for key, value in data.iteritems():
+        if isinstance(key, unicode):
+            key = key.encode('utf-8')
+        if isinstance(value, unicode):
+            value = value.encode('utf-8')
+        elif isinstance(value, list):
+            value = _decode_list(value)
+        elif isinstance(value, dict):
+            value = _decode_dict(value)
+        rv[key] = value
+    return rv
+
+
 def parse_json_metadata(metafile):
 
     appid = os.path.basename(metafile)[0:-5]  # strip path and .json
@@ -623,6 +653,7 @@ def parse_json_metadata(metafile):
     # fdroid metadata is only strings and booleans, no floats or ints. And
     # json returns unicode, and fdroidserver still uses plain python strings
     jsoninfo = json.load(open(metafile, 'r'),
+                         object_hook=_decode_dict,
                          parse_int=lambda s: s,
                          parse_float=lambda s: s)
     supported_metadata = app_defaults.keys() + ['builds', 'comments']