introduce debugging.. but dont actually use it anywhere

code/app.py

@@ -17,6 +17,7 @@ app.config['UPLOAD_FOLDER'] = 'data/'
 app.config['SHARES_FILE'] = 'data/shares.json'
 app.config['DATE_FORMAT'] = "%Y-%m-%d %H:%M"
 app.config['UID'] = 1000
+app.config['DEBUG'] = False
 
 app.secret_key = 'Cz2dw5NiRt3PSMFBSLTAJJi7U2CdW7iPQqEeOaU6'
 app.wsgi_app = ReverseProxied(app.wsgi_app)
@@ -27,7 +28,6 @@ def before_request():
 
 @app.route("/")
 def index():
-    printerr(g.shares)
     public_shares = []
     for share in g.shares:
         public = get_or_none(share,'public')
@@ -70,6 +70,7 @@ def upload(name = None, password = None):
                 )
             )
             if get_or_none(share, 'overwrite') == False:
+                if os.path.exists(filename):
                     return "Overwrite forbidden", 403
             file.save(filename)
             os.chown(filename, app.config['UID'], -1)
@@ -198,7 +199,8 @@ def is_expired(share):
             return True
     return False
 
-def printerr(s):
+def print_debug(s):
+    if app.config['DEBUG']:
         sys.stderr.write(str(s)+"\n")
         sys.stderr.flush()