provide qr codes for printing

datentrog.py

@@ -1,5 +1,8 @@
 #!/usr/bin/env python3
 import bottle
+import io
+import qrcode
+import qrcode.image.styledpil as qrstyled
 import sqlite3
 
 
@@ -18,6 +21,13 @@ cursor.execute("""
     """)
 
 
+def url(route):
+    return '%s://%s/%s' % (
+            bottle.request.urlparts.scheme,
+            bottle.request.urlparts.netloc,
+            route)
+
+
 @application.get("/")
 @bottle.view("template/new.tpl")
 def new_get():
@@ -29,7 +39,7 @@ def new_get():
 def new_post():
     event = bottle.request.forms.get("event", "")
     if event:
-        bottle.redirect("event/" + event)
+        bottle.redirect(url("qr/" + event))
     return dict(event=event, feedback=True)
 
 
@@ -38,6 +48,23 @@ def static_get(file):
     return bottle.static_file(file, root="static")
 
 
+@application.get("/qr/<event>")
+@bottle.view("template/qr.tpl")
+def qr_get(event):
+    return dict(event=event, url=url("event/" + event))
+
+
+@application.get("/qr/img/<event>.png")
+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")
+    buffer = io.BytesIO()
+    image.save(buffer, format="PNG")
+    bottle.response.content_type = "image/png"
+    return buffer.getvalue()
+
+
 @application.get("/event/<event>")
 @bottle.view("template/event.tpl")
 def event_get(event):

requirements.txt

@@ -1 +1,2 @@
 bottle
+qrcode[pil]

template/event.tpl

@@ -1,4 +1,4 @@
-% rebase('template/toplevel.tpl', title=event)
+% rebase("template/toplevel.tpl", title=event)
 % if get("success", False):
 <div class="alert alert-success">Erfolgreich registriert.</div>
 <form method="get">

template/new.tpl

@@ -1,8 +1,8 @@
-% rebase('template/toplevel.tpl', title='Neu erstellen')
+% rebase("template/toplevel.tpl", title="Neu erstellen")
 <form method="post">
   <div class="form-group {{ ("has-success" if get("event", False) else "has-error") + " has-feedback" if get("feedback", False) else "" }}">
     <label for="event">Veranstaltungsort:</label>
-    <input id="event" class="form-control" placeholder="Kunstrasen" name="event" value="{{ get("event", "") }}">
+    <input id="event" class="form-control" placeholder="Heizhaus" name="event" value="{{ get("event", "") }}">
     % if get("feedback", False):
     <span class="glyphicon {{ "glyphicon-ok" if get("event", False) else "glyphicon-remove" }} form-control-feedback"></span>
     % end

template/qr.tpl

@@ -0,0 +1,7 @@
+% rebase("template/toplevel.tpl", title=event)
+<div class="hidden-print">
+  <a class="btn btn-default" href="{{ url }}">Zum Formular</a>
+  <button class="btn btn-primary" onclick="window.print()">Drucken</button>
+</div>
+<img class="img-responsive" src="img/{{ event }}.png" alt="QR-Code">
+<p class="lead">{{ url }}</p>