add license and reformat with black

LICENSE

@@ -0,0 +1,16 @@
+This license does not apply to the heizhaus_logo* files and anything in
+the static/bootstrap-3.4.1-dist directory
+---
+Copyright (c) 2021 Thomas Lindner <tom@dl6tom.de>
+
+Permission to use, copy, modify, and distribute this software for any
+purpose with or without fee is hereby granted, provided that the above
+copyright notice and this permission notice appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

datentrog.py

@@ -9,7 +9,8 @@ import sqlite3
 application = bottle.default_app()
 connection = sqlite3.connect("db.sqlite")
 cursor = connection.cursor()
-cursor.execute("""
+cursor.execute(
+    """
     CREATE TABLE IF NOT EXISTS visitors (
         id      INTEGER PRIMARY KEY AUTOINCREMENT,
         event   TEXT,
@@ -18,14 +19,16 @@ cursor.execute("""
         address TEXT,
         contact TEXT
     );
-    """)
+    """
+)
 
 
 def url(route):
-    return '%s://%s/%s' % (
+    return "%s://%s/%s" % (
         bottle.request.urlparts.scheme,
         bottle.request.urlparts.netloc,
-            route)
+        route,
+    )
 
 
 @application.get("/")
@@ -58,7 +61,10 @@ def qr_get(event):
 def qr_img_get(event):
     qr = qrcode.QRCode(error_correction=qrcode.constants.ERROR_CORRECT_H, box_size=20)
     qr.add_data(url("event/" + event))
-    image = qr.make_image(image_factory=qrstyled.StyledPilImage, embeded_image_path="heizhaus_logo_square.png")
+    image = qr.make_image(
+        image_factory=qrstyled.StyledPilImage,
+        embeded_image_path="heizhaus_logo_square.png",
+    )
     buffer = io.BytesIO()
     image.save(buffer, format="PNG")
     bottle.response.content_type = "image/png"
@@ -79,19 +85,24 @@ def event_post(event):
         data[field] = bottle.request.forms.get(field, "")
         data["success"] = data["success"] and data[field]
     if data["success"]:
-        cursor.execute("""
+        cursor.execute(
+            """
             INSERT INTO visitors (event, time, name, address, contact)
                 VALUES (:event, datetime('now'), :name, :address, :contact);
-            """, data)
+            """,
+            data,
+        )
         connection.commit()
     return data
 
 
 @application.get("/cleanup")
 def cleanup():
-    cursor.execute("""
+    cursor.execute(
+        """
         DELETE FROM visitors WHERE time < datetime('now', '-1 month');
-        """)
+        """
+    )
     connection.commit()