From ed8363f163291cf96689f259c0fc86bfc337595b Mon Sep 17 00:00:00 2001
From: Daniel Grams <grams.daniel@gmail.com>
Date: Thu, 27 May 2021 14:14:38 +0200
Subject: [PATCH] Add meta tags for social media #181

---
 project/services/event.py                     | 37 +++++++++++++++++++
 project/templates/admin/admin.html            |  4 +-
 project/templates/admin/admin_units.html      |  4 +-
 project/templates/admin/settings.html         |  4 +-
 .../templates/admin/update_admin_unit.html    |  4 +-
 project/templates/admin/update_user.html      |  4 +-
 project/templates/admin/users.html            |  4 +-
 project/templates/developer/read.html         |  4 +-
 project/templates/event/actions.html          |  4 +-
 project/templates/event/create.html           |  4 +-
 project/templates/event/read.html             |  4 +-
 project/templates/event/reference.html        |  4 +-
 .../templates/event/reference_request.html    |  4 +-
 project/templates/event/update.html           |  4 +-
 project/templates/event_date/list.html        |  4 +-
 project/templates/event_date/read.html        |  6 +--
 project/templates/event_date/search.html      |  4 +-
 project/templates/event_place/list.html       |  4 +-
 project/templates/event_place/read.html       |  4 +-
 .../templates/event_suggestion/reject.html    |  4 +-
 .../templates/event_suggestion/review.html    |  4 +-
 .../event_suggestion/review_status.html       |  4 +-
 project/templates/example.html                |  4 +-
 project/templates/home.html                   |  4 +-
 project/templates/invitation/read.html        |  4 +-
 project/templates/layout.html                 | 30 ++++++++++++---
 project/templates/legal.html                  |  4 +-
 project/templates/manage/admin_units.html     |  4 +-
 project/templates/manage/events.html          |  4 +-
 project/templates/manage/members.html         |  4 +-
 project/templates/manage/organizers.html      |  4 +-
 project/templates/manage/places.html          |  4 +-
 .../manage/reference_requests_incoming.html   |  4 +-
 .../manage/reference_requests_outgoing.html   |  4 +-
 .../templates/manage/references_incoming.html |  4 +-
 .../templates/manage/references_outgoing.html |  4 +-
 project/templates/manage/reviews.html         |  4 +-
 project/templates/manage/widgets.html         |  4 +-
 project/templates/oauth2_client/create.html   |  4 +-
 project/templates/oauth2_client/list.html     |  4 +-
 project/templates/oauth2_client/read.html     |  4 +-
 project/templates/oauth2_client/update.html   |  4 +-
 project/templates/oauth2_token/list.html      |  4 +-
 project/templates/organization/read.html      |  4 +-
 project/templates/planing/list.html           |  4 +-
 project/templates/profile.html                |  4 +-
 project/templates/reference/read.html         |  4 +-
 project/templates/reference/update.html       |  4 +-
 .../templates/reference_request/review.html   |  4 +-
 .../reference_request/review_status.html      |  4 +-
 project/templates/widget/event_date/list.html |  4 +-
 project/templates/widget/event_date/read.html |  4 +-
 .../widget/event_suggestion/create.html       |  4 +-
 project/templates/widget/infoscreen/read.html |  4 +-
 project/views/event.py                        |  2 +
 project/views/event_date.py                   |  6 ++-
 tests/services/test_event.py                  | 22 +++++++++++
 57 files changed, 195 insertions(+), 112 deletions(-)

diff --git a/project/services/event.py b/project/services/event.py
index cb4c7a7..6b97205 100644
--- a/project/services/event.py
+++ b/project/services/event.py
@@ -1,6 +1,8 @@
 from datetime import datetime
 
 from dateutil.relativedelta import relativedelta
+from flask import url_for
+from flask_babelex import format_date, format_time
 from sqlalchemy import and_, func, or_
 from sqlalchemy.orm import contains_eager, defaultload, joinedload, lazyload
 from sqlalchemy.sql import extract
@@ -10,6 +12,7 @@ from project.dateutils import date_add_time, dates_from_recurrence_rule, get_tod
 from project.models import (
     AdminUnit,
     Event,
+    EventAttendanceMode,
     EventCategory,
     EventDate,
     EventOrganizer,
@@ -20,6 +23,7 @@ from project.models import (
     Location,
 )
 from project.utils import get_pending_changes
+from project.views.utils import truncate
 
 
 def get_event_category(category_name):
@@ -313,3 +317,36 @@ def get_significant_event_changes(event) -> dict:
         "organizer_id",
     ]
     return get_pending_changes(event, include_collections=False, include_keys=keys)
+
+
+def get_meta_data(event: Event, event_date: EventDate = None) -> dict:
+    meta = dict()
+    meta["title"] = event.name
+
+    if (
+        event.attendance_mode
+        and event.attendance_mode != EventAttendanceMode.online
+        and event.event_place
+    ):
+        meta["title"] = f"{meta['title']} @ {event.event_place.name}"
+
+        if event.event_place.location and event.event_place.location.city:
+            meta["title"] = f"{meta['title']}, {event.event_place.location.city}"
+
+    if event_date:
+        date_str = format_date(event_date.start, "full")
+        time_str = format_time(event_date.start, "short")
+        meta["description"] = f"{date_str} {time_str}"
+
+    if event.description:
+        desc_short = truncate(event.description, 300)
+
+        if "description" in meta:
+            meta["description"] = f"{meta['description']}: {desc_short}"
+        else:
+            meta["description"] = desc_short
+
+    if event.photo_id:
+        meta["image"] = url_for("image", id=event.photo_id, _external=True)
+
+    return meta
diff --git a/project/templates/admin/admin.html b/project/templates/admin/admin.html
index 0c3b183..8e096a5 100644
--- a/project/templates/admin/admin.html
+++ b/project/templates/admin/admin.html
@@ -1,7 +1,7 @@
 {% extends "layout.html" %}
-{% block title %}
+{%- block title -%}
 {{ _('Admin') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <nav aria-label="breadcrumb">
diff --git a/project/templates/admin/admin_units.html b/project/templates/admin/admin_units.html
index 7903138..62680f2 100644
--- a/project/templates/admin/admin_units.html
+++ b/project/templates/admin/admin_units.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_pagination %}
-{% block title %}
+{%- block title -%}
 {{ _('Organizations') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <nav aria-label="breadcrumb">
diff --git a/project/templates/admin/settings.html b/project/templates/admin/settings.html
index 326380f..1e070e1 100644
--- a/project/templates/admin/settings.html
+++ b/project/templates/admin/settings.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_field, render_field_with_errors %}
-{% block title %}
+{%- block title -%}
 {{ _('Settings') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1>{{ _('Settings') }}</h1>
diff --git a/project/templates/admin/update_admin_unit.html b/project/templates/admin/update_admin_unit.html
index 1499a0a..89ae3d9 100644
--- a/project/templates/admin/update_admin_unit.html
+++ b/project/templates/admin/update_admin_unit.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_field_with_errors, render_field %}
-{% block title %}
+{%- block title -%}
 {{ _('Update organization') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1>{{ _('Update organization') }}</h1>
diff --git a/project/templates/admin/update_user.html b/project/templates/admin/update_user.html
index e429795..d65b11b 100644
--- a/project/templates/admin/update_user.html
+++ b/project/templates/admin/update_user.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_field_with_errors, render_field %}
-{% block title %}
+{%- block title -%}
 {{ _('Update user') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1>{{ _('Update user') }}</h1>
diff --git a/project/templates/admin/users.html b/project/templates/admin/users.html
index b33d76c..a3c89db 100644
--- a/project/templates/admin/users.html
+++ b/project/templates/admin/users.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_pagination %}
-{% block title %}
+{%- block title -%}
 {{ _('Users') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <nav aria-label="breadcrumb">
diff --git a/project/templates/developer/read.html b/project/templates/developer/read.html
index 2e07a2c..706e98e 100644
--- a/project/templates/developer/read.html
+++ b/project/templates/developer/read.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_event_props, render_image_with_link, render_place, render_link_prop %}
-{% block title %}
+{%- block title -%}
 {{ _('Developer') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1>Developer</h1>
diff --git a/project/templates/event/actions.html b/project/templates/event/actions.html
index 3ca5d15..4a1a622 100644
--- a/project/templates/event/actions.html
+++ b/project/templates/event/actions.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_event_props %}
-{% block title %}
+{%- block title -%}
 {{ _('Actions for event') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
     <div class="w-normal">
diff --git a/project/templates/event/create.html b/project/templates/event/create.html
index 501434f..06885b5 100644
--- a/project/templates/event/create.html
+++ b/project/templates/event/create.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_google_place_autocomplete_field, render_google_place_autocomplete_header, render_cropper_header, render_cropper_code, render_crop_image_form_section, render_radio_buttons, render_datepicker_js, render_field_with_errors, render_field %}
-{% block title %}
+{%- block title -%}
 {{ _('Create event') }}
-{% endblock %}
+{%- endblock -%}
 {% block header %}
 {{ render_cropper_header() }}
 {{ render_google_place_autocomplete_header(False, 'new_event_place-') }}
diff --git a/project/templates/event/read.html b/project/templates/event/read.html
index a40daa9..e81c0f5 100644
--- a/project/templates/event/read.html
+++ b/project/templates/event/read.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_event_props_seo %}
-{% block title %}
+{%- block title -%}
 {{ event.name }}
-{% endblock %}
+{%- endblock -%}
 {% block content_container_attribs %}{% endblock %}
 {% block content %}
 
diff --git a/project/templates/event/reference.html b/project/templates/event/reference.html
index 54bdd34..774adaa 100644
--- a/project/templates/event/reference.html
+++ b/project/templates/event/reference.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_radio_buttons, render_phone_prop, render_email_prop, render_string_prop, render_field_with_errors, render_field, render_event_props, render_image_with_link, render_place, render_link_prop %}
-{% block title %}
+{%- block title -%}
 {{ event.name }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1>{{ _('Reference event "%(name)s"', name=event.name) }}</h1>
diff --git a/project/templates/event/reference_request.html b/project/templates/event/reference_request.html
index 1f3f4f1..31a9be2 100644
--- a/project/templates/event/reference_request.html
+++ b/project/templates/event/reference_request.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_radio_buttons, render_phone_prop, render_email_prop, render_string_prop, render_field_with_errors, render_field, render_event_props, render_image_with_link, render_place, render_link_prop %}
-{% block title %}
+{%- block title -%}
 {{ event.name }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1>{{ _('Request reference for event "%(name)s"', name=event.name) }}</h1>
diff --git a/project/templates/event/update.html b/project/templates/event/update.html
index 6f72d46..dc7a1cc 100644
--- a/project/templates/event/update.html
+++ b/project/templates/event/update.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_cropper_block, render_crop_image_form_section, render_radio_buttons, render_datepicker_js, render_field_with_errors, render_field %}
-{% block title %}
+{%- block title -%}
 {{ _('Update event') }}
-{% endblock %}
+{%- endblock -%}
 {% block header %}
   {{ render_cropper_block() }}
   <script>
diff --git a/project/templates/event_date/list.html b/project/templates/event_date/list.html
index 0c86942..26f5d08 100644
--- a/project/templates/event_date/list.html
+++ b/project/templates/event_date/list.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_google_filter_autocomplete_header, render_event_dates_filter_form, render_pagination, render_place, render_events_sub_menu %}
-{% block title %}
+{%- block title -%}
 {{ _('Event Dates') }}
-{% endblock %}
+{%- endblock -%}
 {% block header %}
 {{ render_google_filter_autocomplete_header() }}
 <script>
diff --git a/project/templates/event_date/read.html b/project/templates/event_date/read.html
index 78aaba4..80257ce 100644
--- a/project/templates/event_date/read.html
+++ b/project/templates/event_date/read.html
@@ -1,9 +1,9 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_event_props_seo %}
 {% set event = event_date.event %}
-{% block title %}
-{{ event_date.start | dateformat() }} {{ event.name }}
-{% endblock %}
+{%- block title -%}
+{{ meta['title'] }}
+{%- endblock -%}
 {% block content_container_attribs %}{% endblock %}
 {% block content %}
 
diff --git a/project/templates/event_date/search.html b/project/templates/event_date/search.html
index 552358a..d8db66b 100644
--- a/project/templates/event_date/search.html
+++ b/project/templates/event_date/search.html
@@ -1,7 +1,7 @@
 {% extends "layout.html" %}
-{% block title %}
+{%- block title -%}
 {{ _('Event Dates') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <event-date-search basepath="{{ url_for('home', _external=True) }}"></event-date-search>
diff --git a/project/templates/event_place/list.html b/project/templates/event_place/list.html
index 391c867..ec63c45 100644
--- a/project/templates/event_place/list.html
+++ b/project/templates/event_place/list.html
@@ -1,7 +1,7 @@
 {% extends "layout.html" %}
-{% block title %}
+{%- block title -%}
 {{ _('Places') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
     <h1>{{ _('Places') }}</h1>
diff --git a/project/templates/event_place/read.html b/project/templates/event_place/read.html
index a005096..5e910c3 100644
--- a/project/templates/event_place/read.html
+++ b/project/templates/event_place/read.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_place, render_events, render_location_card, render_link_prop, render_image %}
-{% block title %}
+{%- block title -%}
 {{ place.name }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
     <h1>{{ place.name }}</h1>
diff --git a/project/templates/event_suggestion/reject.html b/project/templates/event_suggestion/reject.html
index 4737795..cbf8472 100644
--- a/project/templates/event_suggestion/reject.html
+++ b/project/templates/event_suggestion/reject.html
@@ -1,9 +1,9 @@
 {% extends "layout_manage.html" %}
 {% set active_id = "reviews" %}
 {% from "_macros.html" import render_event_suggestion, render_image, render_radio_buttons, render_phone_prop, render_email_prop, render_string_prop, render_field_with_errors, render_field, render_event_props, render_image_with_link, render_place, render_link_prop %}
-{% block title %}
+{%- block title -%}
 {{ event_suggestion.name }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1>{{ _('Reject event suggestion') }}</h1>
diff --git a/project/templates/event_suggestion/review.html b/project/templates/event_suggestion/review.html
index d6133e4..54ec5be 100644
--- a/project/templates/event_suggestion/review.html
+++ b/project/templates/event_suggestion/review.html
@@ -1,9 +1,9 @@
 {% extends "layout_manage.html" %}
 {% set active_id = "reviews" %}
 {% from "_macros.html" import render_event_suggestion, render_image, render_radio_buttons, render_phone_prop, render_email_prop, render_string_prop, render_field_with_errors, render_field, render_event_props, render_image_with_link, render_place, render_link_prop %}
-{% block title %}
+{%- block title -%}
 {{ event_suggestion.name }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1>{{ _('Review event suggestion') }}</h1>
diff --git a/project/templates/event_suggestion/review_status.html b/project/templates/event_suggestion/review_status.html
index 70f34ac..be8a3b1 100644
--- a/project/templates/event_suggestion/review_status.html
+++ b/project/templates/event_suggestion/review_status.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_event_review_status, render_event_props, render_image_with_link, render_place, render_link_prop %}
-{% block title %}
+{%- block title -%}
 {{ event_suggestion.name }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
     <h1>{{ event_suggestion.name }}</h1>
diff --git a/project/templates/example.html b/project/templates/example.html
index c9fe4de..be8ba32 100644
--- a/project/templates/example.html
+++ b/project/templates/example.html
@@ -1,7 +1,7 @@
 {% extends "layout.html" %}
-{% block title %}
+{%- block title -%}
 oveda - Terminkalender für Goslar und Hahnenklee
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1>Terminkalender für Goslar und Hahnenklee</h1>
diff --git a/project/templates/home.html b/project/templates/home.html
index f82c11d..1c14d38 100644
--- a/project/templates/home.html
+++ b/project/templates/home.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_place, render_events_sub_menu %}
-{% block title %}
+{%- block title -%}
 oveda - Offene Veranstaltungsdatenbank
-{% endblock %}
+{%- endblock -%}
 {% block styles %}
 <link rel="stylesheet" type="text/css" href="{{ url_for('static', filename='landing-page.css')}}" />
 {% endblock %}
diff --git a/project/templates/invitation/read.html b/project/templates/invitation/read.html
index 104f662..5e674c9 100644
--- a/project/templates/invitation/read.html
+++ b/project/templates/invitation/read.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_field %}
-{% block title %}
+{%- block title -%}
 {{ _('Invitation') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1>{{ _('Invitation') }}</h1>
diff --git a/project/templates/layout.html b/project/templates/layout.html
index 0135e0f..4edde16 100644
--- a/project/templates/layout.html
+++ b/project/templates/layout.html
@@ -4,14 +4,36 @@
   {%- block html %}
   <head>
     {%- block head %}
-    <!-- Required meta tags -->
+    <title>{%- block title -%}{{ title|default('oveda') }}{% endblock title %}</title>
     <meta charset="utf-8">
     <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
-    <meta name="description" content="{% if meta_description %}{{ meta_description }}{% else %}Mit der offenen Veranstaltungsdatenbank Events einfach bekannt machen!{% endif %}">
+
     {% if canonical_url %}
     <link rel="canonical" href="{{ canonical_url }}" />
     {% endif %}
     {%- block metas %}
+      <meta property="og:type" content="website">
+      <meta property="og:title" content="{{ self.title() }}">
+
+      {% if meta %}
+        <meta name="description" content="{{ meta['description'] }}">
+        <meta property="og:description" content="{{ meta['description'] }}">
+
+        {% if 'image' in meta %}
+          <meta property="og:image" content="{{ meta['image'] }}">
+          <meta name="twitter:card" content="summary_large_image">
+        {% else %}
+        <meta name="twitter:card" content="summary">
+        {% endif %}
+
+      {% else %}
+        <meta name="description" content="Mit der offenen Veranstaltungsdatenbank Events einfach bekannt machen!">
+        <meta property="og:description" content="Mit der offenen Veranstaltungsdatenbank Events einfach bekannt machen!">
+      {% endif %}
+
+      {% if canonical_url %}
+        <link rel="og:url" href="{{ canonical_url }}" />
+      {% endif %}
     {%- endblock metas %}
 
     <!-- Bootstrap CSS -->
@@ -41,7 +63,7 @@
     <script src="{{ url_for('static', filename='jquery.recurrenceinput.js')}}"></script>
 
     {% block header_before_site_js %}
-    {% endblock %}
+    {%- endblock -%}
     <script src="{{ url_for('static', filename='site.js')}}"></script>
     <script src="{{ url_for('static', filename='svg-icon.js')}}"></script>
 
@@ -107,8 +129,6 @@
 
     </script>
 
-    <title>{% block title %}{{ title|default('oveda') }}{% endblock title %}</title>
-
     {% if structured_data %}
     <script type="application/ld+json">
       {{ structured_data | safe }}
diff --git a/project/templates/legal.html b/project/templates/legal.html
index 2632565..bbbf61f 100644
--- a/project/templates/legal.html
+++ b/project/templates/legal.html
@@ -1,7 +1,7 @@
 {% extends "layout.html" %}
-{% block title %}
+{%- block title -%}
 {{ title }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 {{ content }}
 {% endblock %}
\ No newline at end of file
diff --git a/project/templates/manage/admin_units.html b/project/templates/manage/admin_units.html
index 74a975f..0d8d519 100644
--- a/project/templates/manage/admin_units.html
+++ b/project/templates/manage/admin_units.html
@@ -1,7 +1,7 @@
 {% extends "layout.html" %}
-{% block title %}
+{%- block title -%}
 {{ _('Organizations') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 {% if invitations %}
diff --git a/project/templates/manage/events.html b/project/templates/manage/events.html
index 2f78615..c5ae8bf 100644
--- a/project/templates/manage/events.html
+++ b/project/templates/manage/events.html
@@ -1,9 +1,9 @@
 {% extends "layout_manage.html" %}
 {% set active_id = "events" %}
 {% from "_macros.html" import render_event_dates_filter_form, render_event_warning_pills, render_pagination, render_event_date, render_field_with_errors, render_event_organizer %}
-{% block title %}
+{%- block title -%}
 {{ _('Events') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1>{{ _('Events') }} <button type="button" class="btn btn-outline-secondary mx-2" data-toggle="collapse" data-target="#search_form" aria-expanded="{% if form.is_submitted() %}true{% else %}false{% endif %}"><i class="fa fa-search"></i></button></h1>
diff --git a/project/templates/manage/members.html b/project/templates/manage/members.html
index 60ca29c..34b5eaa 100644
--- a/project/templates/manage/members.html
+++ b/project/templates/manage/members.html
@@ -1,9 +1,9 @@
 {% extends "layout_manage.html" %}
 {% set active_id = "members" %}
 {% from "_macros.html" import render_roles, render_pagination, render_event_organizer %}
-{% block title %}
+{%- block title -%}
 {{ _('Members') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1>{{ _('Invitations') }}</h1>
diff --git a/project/templates/manage/organizers.html b/project/templates/manage/organizers.html
index 176c6db..a85f14b 100644
--- a/project/templates/manage/organizers.html
+++ b/project/templates/manage/organizers.html
@@ -1,9 +1,9 @@
 {% extends "layout_manage.html" %}
 {% set active_id = "organizers" %}
 {% from "_macros.html" import render_pagination, render_event_organizer %}
-{% block title %}
+{%- block title -%}
 {{ _('Organizers') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1>{{ _('Organizers') }}</h1>
diff --git a/project/templates/manage/places.html b/project/templates/manage/places.html
index c1feea4..b3bdb7b 100644
--- a/project/templates/manage/places.html
+++ b/project/templates/manage/places.html
@@ -1,9 +1,9 @@
 {% extends "layout_manage.html" %}
 {% set active_id = "places" %}
 {% from "_macros.html" import render_pagination, render_field_with_errors, render_event_organizer %}
-{% block title %}
+{%- block title -%}
 {{ _('Places') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1>{{ _('Places') }}</h1>
diff --git a/project/templates/manage/reference_requests_incoming.html b/project/templates/manage/reference_requests_incoming.html
index d52b87f..95a5875 100644
--- a/project/templates/manage/reference_requests_incoming.html
+++ b/project/templates/manage/reference_requests_incoming.html
@@ -1,9 +1,9 @@
 {% extends "layout_manage.html" %}
 {% set active_id = "reference_requests_incoming" %}
 {% from "_macros.html" import render_reference_request_review_status_pill, render_event_date, render_pagination, render_event_organizer %}
-{% block title %}
+{%- block title -%}
 {{ _('Reference requests') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1 class="mb-1">{{ _('Incoming reference requests') }}</h1>
diff --git a/project/templates/manage/reference_requests_outgoing.html b/project/templates/manage/reference_requests_outgoing.html
index 93b1e3f..b786513 100644
--- a/project/templates/manage/reference_requests_outgoing.html
+++ b/project/templates/manage/reference_requests_outgoing.html
@@ -1,9 +1,9 @@
 {% extends "layout_manage.html" %}
 {% set active_id = "reference_requests_outgoing" %}
 {% from "_macros.html" import render_reference_request_review_status_pill, render_event_date, render_pagination, render_event_organizer %}
-{% block title %}
+{%- block title -%}
 {{ _('Reference requests') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1 class="mb-1">{{ _('Outgoing reference requests') }}</h1>
diff --git a/project/templates/manage/references_incoming.html b/project/templates/manage/references_incoming.html
index cfeb6fe..af080e4 100644
--- a/project/templates/manage/references_incoming.html
+++ b/project/templates/manage/references_incoming.html
@@ -1,9 +1,9 @@
 {% extends "layout_manage.html" %}
 {% set active_id = "references_incoming" %}
 {% from "_macros.html" import render_event_warning_pills, render_event_date, render_pagination, render_event_organizer %}
-{% block title %}
+{%- block title -%}
 {{ _('References') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1 class="mb-1">{{ _('Incoming references') }}</h1>
diff --git a/project/templates/manage/references_outgoing.html b/project/templates/manage/references_outgoing.html
index 64ae808..255960d 100644
--- a/project/templates/manage/references_outgoing.html
+++ b/project/templates/manage/references_outgoing.html
@@ -1,9 +1,9 @@
 {% extends "layout_manage.html" %}
 {% set active_id = "references_outgoing" %}
 {% from "_macros.html" import render_event_warning_pills, render_event_date, render_pagination, render_event_organizer %}
-{% block title %}
+{%- block title -%}
 {{ _('References') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1 class="mb-1">{{ _('Outgoing references') }}</h1>
diff --git a/project/templates/manage/reviews.html b/project/templates/manage/reviews.html
index ecadc47..c2a959e 100644
--- a/project/templates/manage/reviews.html
+++ b/project/templates/manage/reviews.html
@@ -1,9 +1,9 @@
 {% extends "layout_manage.html" %}
 {% set active_id = "reviews" %}
 {% from "_macros.html" import render_event_review_status_pill, render_pagination, render_event_date, render_field_with_errors, render_event_organizer %}
-{% block title %}
+{%- block title -%}
 {{ _('Reviews') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1 class="mb-1">{{ _('Reviews') }}</h1>
diff --git a/project/templates/manage/widgets.html b/project/templates/manage/widgets.html
index 21c3d4c..e93918b 100644
--- a/project/templates/manage/widgets.html
+++ b/project/templates/manage/widgets.html
@@ -1,9 +1,9 @@
 {% extends "layout_manage.html" %}
 {% set active_id = "widgets" %}
 {% from "_macros.html" import render_pagination, render_event_date, render_field, render_field_with_errors, render_event_organizer %}
-{% block title %}
+{%- block title -%}
 {{ _('Widgets') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1>{{ _('Widgets') }} <a class="btn btn-light" role="button" data-toggle="collapse" href="#settingsContainer" aria-expanded="false" aria-controls="settingsContainer"><i class="fa fa-cog"></i></a></h1>
diff --git a/project/templates/oauth2_client/create.html b/project/templates/oauth2_client/create.html
index 72b3796..4c4f6ba 100644
--- a/project/templates/oauth2_client/create.html
+++ b/project/templates/oauth2_client/create.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_field_with_errors, render_field %}
-{% block title %}
+{%- block title -%}
 {{ _('Create OAuth2 client') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1>{{ _('Create OAuth2 client') }}</h1>
diff --git a/project/templates/oauth2_client/list.html b/project/templates/oauth2_client/list.html
index 218b451..772dc96 100644
--- a/project/templates/oauth2_client/list.html
+++ b/project/templates/oauth2_client/list.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_pagination %}
-{% block title %}
+{%- block title -%}
 {{ _('OAuth2 clients') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <nav aria-label="breadcrumb">
diff --git a/project/templates/oauth2_client/read.html b/project/templates/oauth2_client/read.html
index 4cdfb5b..ae8205f 100644
--- a/project/templates/oauth2_client/read.html
+++ b/project/templates/oauth2_client/read.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_kv_begin, render_kv_end, render_kv_prop %}
-{% block title %}
+{%- block title -%}
 {{ oauth2_client.client_name }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <nav aria-label="breadcrumb">
diff --git a/project/templates/oauth2_client/update.html b/project/templates/oauth2_client/update.html
index 7b278ff..de56438 100644
--- a/project/templates/oauth2_client/update.html
+++ b/project/templates/oauth2_client/update.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_field_with_errors, render_field %}
-{% block title %}
+{%- block title -%}
 {{ _('Update OAuth2 client') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1>{{ _('Update OAuth2 client') }}</h1>
diff --git a/project/templates/oauth2_token/list.html b/project/templates/oauth2_token/list.html
index 81146f0..d487de8 100644
--- a/project/templates/oauth2_token/list.html
+++ b/project/templates/oauth2_token/list.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_pagination %}
-{% block title %}
+{%- block title -%}
 {{ _('OAuth2 tokens') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <nav aria-label="breadcrumb">
diff --git a/project/templates/organization/read.html b/project/templates/organization/read.html
index 5458bb8..5fdd1a0 100644
--- a/project/templates/organization/read.html
+++ b/project/templates/organization/read.html
@@ -1,7 +1,7 @@
 {% extends "layout.html" %}
-{% block title %}
+{%- block title -%}
 {{ organization.name }}
-{% endblock %}
+{%- endblock -%}
 {% block content_container_attribs %}{% endblock %}
 {% block content %}
 
diff --git a/project/templates/planing/list.html b/project/templates/planing/list.html
index cbac7a0..d7885e4 100644
--- a/project/templates/planing/list.html
+++ b/project/templates/planing/list.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_field, render_field_with_errors, render_event_dates_date_field, render_event_dates_location_field, render_google_filter_autocomplete_header, render_event_dates_filter_form, render_pagination, render_place, render_events_sub_menu %}
-{% block title %}
+{%- block title -%}
 {{ _('Event Planing') }}
-{% endblock %}
+{%- endblock -%}
 {% block content_container_attribs %}{% endblock %}
 {% block header %}
 {{ render_google_filter_autocomplete_header() }}
diff --git a/project/templates/profile.html b/project/templates/profile.html
index 26913ba..3b62626 100644
--- a/project/templates/profile.html
+++ b/project/templates/profile.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_roles %}
-{% block title %}
+{%- block title -%}
 {{ _('Profile') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1>{{ current_user.email }}</h1>
diff --git a/project/templates/reference/read.html b/project/templates/reference/read.html
index 5793a06..9dd9489 100644
--- a/project/templates/reference/read.html
+++ b/project/templates/reference/read.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_audit, render_string_prop, render_audit_container, render_event_props %}
-{% block title %}
+{%- block title -%}
 {{ _('Event reference') }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
     <h1>{{ _('Event reference') }}</h1>
diff --git a/project/templates/reference/update.html b/project/templates/reference/update.html
index 2ef9d07..ec407de 100644
--- a/project/templates/reference/update.html
+++ b/project/templates/reference/update.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_field_with_errors, render_field %}
-{% block title %}
+{%- block title -%}
 {{ _('Update reference to event "%(name)s"', name=reference.event.name) }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1>{{ _('Update reference to event "%(name)s"', name=reference.event.name) }}</h1>
diff --git a/project/templates/reference_request/review.html b/project/templates/reference_request/review.html
index 827302c..0938020 100644
--- a/project/templates/reference_request/review.html
+++ b/project/templates/reference_request/review.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_radio_buttons, render_phone_prop, render_email_prop, render_string_prop, render_field_with_errors, render_field, render_event_props, render_image_with_link, render_place, render_link_prop %}
-{% block title %}
+{%- block title -%}
 {{ event.name }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
 <h1>{{ _('Review event reference request') }}</h1>
diff --git a/project/templates/reference_request/review_status.html b/project/templates/reference_request/review_status.html
index f45c109..daa9a52 100644
--- a/project/templates/reference_request/review_status.html
+++ b/project/templates/reference_request/review_status.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_reference_request_review_status, render_event_props, render_image_with_link, render_place, render_link_prop %}
-{% block title %}
+{%- block title -%}
 {{ event.name }}
-{% endblock %}
+{%- endblock -%}
 {% block content %}
 
     <h1>{{ event.name }}</h1>
diff --git a/project/templates/widget/event_date/list.html b/project/templates/widget/event_date/list.html
index ac6321b..04b18cd 100644
--- a/project/templates/widget/event_date/list.html
+++ b/project/templates/widget/event_date/list.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_widget_styles, render_pagination, render_event_warning_pills, render_event_warning_pills, render_place, render_events_sub_menu %}
-{% block title %}
+{%- block title -%}
 {{ _('Widget') }}
-{% endblock %}
+{%- endblock -%}
 {% block styles %}
 <link rel="stylesheet" type="text/css" href="{{ url_for('static', filename='widget.css')}}" />
 {{ render_widget_styles(styles) }}
diff --git a/project/templates/widget/event_date/read.html b/project/templates/widget/event_date/read.html
index 63b3347..6a5afac 100644
--- a/project/templates/widget/event_date/read.html
+++ b/project/templates/widget/event_date/read.html
@@ -1,9 +1,9 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_audit_container, render_widget_styles, render_event_props, render_image_with_link, render_place, render_link_prop %}
 {% set event = event_date.event %}
-{% block title %}
+{%- block title -%}
 {{ event.name }}
-{% endblock %}
+{%- endblock -%}
 {% block styles %}
 <link rel="stylesheet" type="text/css" href="{{ url_for('static', filename='widget.css')}}" />
 {{ render_widget_styles(styles) }}
diff --git a/project/templates/widget/event_suggestion/create.html b/project/templates/widget/event_suggestion/create.html
index 2a37fa9..832f70d 100644
--- a/project/templates/widget/event_suggestion/create.html
+++ b/project/templates/widget/event_suggestion/create.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_widget_styles, render_logo, render_cropper_code, render_crop_image_form, render_jquery_steps_header, render_cropper_header, render_base_image_form, render_radio_buttons, render_datepicker_js, render_field_with_errors, render_field %}
-{% block title %}
+{%- block title -%}
 {{ _('Create event suggestion') }}
-{% endblock %}
+{%- endblock -%}
 {% block styles %}
 <link rel="stylesheet" type="text/css" href="{{ url_for('static', filename='jquery-steps.css')}}" />
 <link rel="stylesheet" type="text/css" href="{{ url_for('static', filename='widget.css')}}" />
diff --git a/project/templates/widget/infoscreen/read.html b/project/templates/widget/infoscreen/read.html
index 5269252..ed664fe 100644
--- a/project/templates/widget/infoscreen/read.html
+++ b/project/templates/widget/infoscreen/read.html
@@ -1,8 +1,8 @@
 {% extends "layout.html" %}
 {% from "_macros.html" import render_widget_styles, render_location, render_location_prop, render_logo, render_pagination, render_event_warning_pills, render_place, render_events_sub_menu %}
-{% block title %}
+{%- block title -%}
 {{ admin_unit.name }} Infoscreen
-{% endblock %}
+{%- endblock -%}
 {% block styles %}
 <link rel="stylesheet" type="text/css" href="{{ url_for('static', filename='infoscreen.css')}}" />
 {{ render_widget_styles(styles) }}
diff --git a/project/views/event.py b/project/views/event.py
index d75d9b2..db9d1be 100644
--- a/project/views/event.py
+++ b/project/views/event.py
@@ -30,6 +30,7 @@ from project.models import (
 )
 from project.services.event import (
     get_event_with_details_or_404,
+    get_meta_data,
     get_significant_event_changes,
     get_upcoming_event_dates,
     insert_event,
@@ -66,6 +67,7 @@ def event(event_id):
         event=event,
         dates=dates,
         structured_datas=structured_datas,
+        meta=get_meta_data(event),
         user_rights=user_rights,
         canonical_url=url_for("event", event_id=event_id, _external=True),
     )
diff --git a/project/views/event_date.py b/project/views/event_date.py
index 9b1a52d..2540317 100644
--- a/project/views/event_date.py
+++ b/project/views/event_date.py
@@ -7,11 +7,12 @@ from project.forms.event_date import FindEventDateForm
 from project.jsonld import DateTimeEncoder, get_sd_for_event_date
 from project.services.event import (
     get_event_date_with_details_or_404,
+    get_meta_data,
     get_upcoming_event_dates,
 )
 from project.services.event_search import EventSearchParams
 from project.views.event import get_event_category_choices, get_menu_user_rights
-from project.views.utils import flash_errors, track_analytics, truncate
+from project.views.utils import flash_errors, track_analytics
 
 
 def prepare_event_date_form(form):
@@ -51,11 +52,12 @@ def event_date(id):
     structured_data = json.dumps(
         get_sd_for_event_date(event_date), indent=2, cls=DateTimeEncoder
     )
+
     return render_template(
         "event_date/read.html",
         event_date=event_date,
         structured_data=structured_data,
-        meta_description=truncate(event_date.event.description, 300),
+        meta=get_meta_data(event_date.event, event_date),
         canonical_url=url_for("event_date", id=id, _external=True),
         user_rights=get_menu_user_rights(event_date.event),
         dates=get_upcoming_event_dates(event_date.event_id),
diff --git a/tests/services/test_event.py b/tests/services/test_event.py
index f30b6a3..efdcc4e 100644
--- a/tests/services/test_event.py
+++ b/tests/services/test_event.py
@@ -103,3 +103,25 @@ def test_update_event_dates_with_recurrence_rule_past_forever(
         event_date = event.dates[366]
         assert event_date.start == create_berlin_date(2021, 1, 3, 14, 30)
         assert event_date.end == create_berlin_date(2021, 1, 3, 16, 30)
+
+
+def test_get_meta_data(seeder, app):
+    user_id, admin_unit_id = seeder.setup_base()
+    event_id = seeder.create_event(admin_unit_id)
+
+    with app.app_context():
+        from project.models import Event, EventAttendanceMode, Location
+        from project.services.event import get_meta_data
+
+        event = Event.query.get(event_id)
+        event.attendance_mode = EventAttendanceMode.offline
+
+        location = Location()
+        location.city = "Stadt"
+        event.event_place.location = location
+
+        event.photo_id = 1
+
+        with app.test_request_context():
+            meta = get_meta_data(event)
+            assert meta is not None