589: add privacy policy and imprint links

.gitignore

@@ -8,6 +8,7 @@ db.sqlite3
 build
 dist
 .vscode
+.idea
 .idea/dataSources.xml
 .idea/misc.xml
 .coverage

example-configs/lunes-cms.ini

@@ -15,6 +15,14 @@ ALLOWED_HOSTS =
 	lunes.tuerantuer.org
 	vokabeltrainer.tuerantuer.org
 
+[legal]
+# URL of the privacy policy, linked in the admin and on the public upload page
+# [optional, defaults to an empty string which hides the link]
+PRIVACY_POLICY_URL = https://lunes.app/datenschutz
+# URL of the imprint, linked in the same places as the privacy policy
+# [optional, defaults to an empty string which hides the link]
+IMPRINT_URL = https://lunes.app/impressum/
+
 [static-files]
 # The directory for static files [required]
 STATIC_ROOT = /var/www/lunes-cms/static

lunes_cms/cms/templates/admin/base.html

@@ -6,6 +6,7 @@
             <a href="https://www.tuerantuer.org/digitalfabrik" target="_blank">
                 <strong>Tür an Tür Digitalfabrik gGmbH</strong>
             </a>
+            {% include "admin/includes/legal_links.html" %}
             <span class="float-right">v{{ jazzmin_settings.site_version }}</span>
         </footer>
     {% endif %}

lunes_cms/cms/templates/admin/includes/legal_links.html

@@ -0,0 +1,14 @@
+{% load i18n %}
+{% if privacy_policy_url or imprint_url %}
+    <span class="legal-links">
+        {% if privacy_policy_url %}
+            <a href="{{ privacy_policy_url }}" target="_blank" rel="noopener noreferrer">{% translate "Privacy policy" %}</a>
+        {% endif %}
+        {% if privacy_policy_url and imprint_url %}
+            <span aria-hidden="true">&middot;</span>
+        {% endif %}
+        {% if imprint_url %}
+            <a href="{{ imprint_url }}" target="_blank" rel="noopener noreferrer">{% translate "Imprint" %}</a>
+        {% endif %}
+    </span>
+{% endif %}

lunes_cms/cms/templates/admin/login.html

@@ -0,0 +1,10 @@
+{% extends "admin/login.html" %}
+
+{# Appends the legal links below the login form. Jazzmin's login template only #}
+{# defines the "content" block, so the form itself is reused via block.super. #}
+{% block content %}
+    {{ block.super }}
+    <div class="text-center mt-3">
+        {% include "admin/includes/legal_links.html" %}
+    </div>
+{% endblock %}

lunes_cms/core/context_processors.py

@@ -6,6 +6,7 @@
 
 from typing import Any
 
+from django.conf import settings
 from django.http import HttpRequest
 
 from ..cms.feedback_filter import filter_feedback_by_creator
@@ -16,6 +17,26 @@
 from ..cmsv2.models import Feedback as FeedbackV2
 
 
+def legal_links_processor(  # pylint: disable=unused-argument
+    request: HttpRequest,
+) -> dict[str, Any]:
+    """
+    This context processor injects the URLs of the privacy policy and the imprint into the
+    template context. They are read per request instead of being passed as static template
+    context, so that the login page (which is rendered for anonymous users) gets them, too.
+
+    :param request: The current http request
+    :type request: ~django.http.HttpRequest
+
+    :return: The template context containing the legal link URLs
+    :rtype: dict
+    """
+    return {
+        "privacy_policy_url": settings.PRIVACY_POLICY_URL,
+        "imprint_url": settings.IMPRINT_URL,
+    }
+
+
 def feedback_processor(request: HttpRequest) -> dict[str, Any]:
     """
     This context processor injects the number of unread feedback entries into the template context.

lunes_cms/core/settings.py

@@ -19,7 +19,7 @@
 from django.utils.translation import gettext_lazy as _
 
 from .logging_formatter import ColorFormatter
-from .utils import strtobool
+from .utils import legal_menu_links, strtobool
 
 ###################
 # CUSTOM SETTINGS #
@@ -39,6 +39,14 @@
 #: How many documents a training sets needs at least to get released
 TRAININGSET_MIN_DOCS = int(os.environ.get("LUNES_CMS_TRAININGSET_MIN_DOCS", 4))
 
+#: URL of the privacy policy which is linked in the admin (user menu, footer and
+#: login page) and on the public upload page. If empty, no link is shown.
+PRIVACY_POLICY_URL = os.environ.get("LUNES_CMS_PRIVACY_POLICY_URL", "")
+
+#: URL of the imprint which is linked in the same places as the privacy policy
+#: (see :attr:`~lunes_cms.core.settings.PRIVACY_POLICY_URL`). If empty, no link is shown.
+IMPRINT_URL = os.environ.get("LUNES_CMS_IMPRINT_URL", "")
+
 #: API Key for OpenAI
 OPENAI_API_KEY = os.environ.get("LUNES_CMS_OPENAI_API_KEY")
 
@@ -195,6 +203,7 @@
                 "django.contrib.messages.context_processors.messages",
                 "lunes_cms.core.context_processors.feedback_processor",
                 "lunes_cms.core.context_processors.feedbackv2_processor",
+                "lunes_cms.core.context_processors.legal_links_processor",
             ],
         },
     },
@@ -614,6 +623,8 @@
         "cmsv2.Feedback": "fas fa-comment",
     },
     "site_version": _cms_version,
+    # Legal links in the user menu. Only rendered if the respective URL is configured.
+    "usermenu_links": legal_menu_links(PRIVACY_POLICY_URL, IMPRINT_URL),
     # Render the Analytics app section directly below Dashboard. Jazzmin's
     # sidebar lists apps in this order; anything not mentioned trails after.
     "order_with_respect_to": ["cmsv2", "analytics", "auth", "cms"],

lunes_cms/core/utils.py

@@ -4,6 +4,7 @@
 
 from django.contrib.staticfiles.storage import ManifestStaticFilesStorage
 from django.core.files.base import File
+from django.utils.translation import gettext_lazy as _
 
 
 class LaxManifestStaticFilesStorage(ManifestStaticFilesStorage):
@@ -27,6 +28,31 @@ def hashed_name(
             return name
 
 
+def legal_menu_links(privacy_policy_url: str, imprint_url: str) -> list[dict[str, Any]]:
+    """Build the Jazzmin user menu entries for the legal links.
+
+    Entries without a configured URL are left out, so an installation which
+    only configures one of the two links does not end up with a dead menu item.
+    Jazzmin passes absolute URLs through unchanged, only URL names without a
+    slash are reversed.
+    """
+    links: list[dict[str, Any]] = [
+        {
+            "name": _("Privacy policy"),
+            "url": privacy_policy_url,
+            "new_window": True,
+            "icon": "fas fa-user-shield",
+        },
+        {
+            "name": _("Imprint"),
+            "url": imprint_url,
+            "new_window": True,
+            "icon": "fas fa-building",
+        },
+    ]
+    return [link for link in links if link["url"]]
+
+
 def strtobool(string: str) -> int:
     """Convert a string representation of truth to true (1) or false (0).
 

lunes_cms/help/templates/public_upload.html

@@ -135,7 +135,7 @@ <h3 class="h5 mb-4 mt-4 font-weight-normal">
         </label>
       </div>
       <button class="btn btn-lg btn-primary btn-block" type="submit">Upload</button>
-      <p class="mt-5 mb-3 text-muted"></p>
+      <p class="mt-5 mb-3 text-muted">{% include "admin/includes/legal_links.html" %}</p>
     </form>
   </body>
 </html>

lunes_cms/locale/de/LC_MESSAGES/django.po

@@ -649,6 +649,14 @@ msgid_plural "and %(remaining)s more objects will be deleted"
 msgstr[0] "und %(remaining)s weiteres Objekt wird gelöscht"
 msgstr[1] "und %(remaining)s weitere Objekte werden gelöscht"
 
+#: cms/templates/admin/includes/legal_links.html core/utils.py
+msgid "Privacy policy"
+msgstr "Datenschutzerklärung"
+
+#: cms/templates/admin/includes/legal_links.html core/utils.py
+msgid "Imprint"
+msgstr "Impressum"
+
 #: cms/templates/admin/object_delete_summary.html
 msgid "Summary"
 msgstr "Zusammenfassung"

tests/core/test_legal_links.py

@@ -0,0 +1,60 @@
+"""
+Tests for the privacy policy and imprint links.
+"""
+
+from __future__ import annotations
+
+import pytest
+from django.contrib.auth.models import User
+from django.test import Client
+from django.test.utils import override_settings
+from django.urls import reverse
+
+from lunes_cms.core.utils import legal_menu_links
+
+PRIVACY_POLICY_URL = "https://lunes.app/datenschutz"
+IMPRINT_URL = "https://www.tuerantuer.org/impressum"
+
+
+@pytest.mark.django_db
+@override_settings(PRIVACY_POLICY_URL=PRIVACY_POLICY_URL, IMPRINT_URL=IMPRINT_URL)
+def test_login_page_shows_legal_links(client: Client) -> None:
+    """Both links have to be reachable without being logged in."""
+    content = client.get(reverse("admin:login")).content.decode()
+    assert PRIVACY_POLICY_URL in content
+    assert IMPRINT_URL in content
+
+
+@pytest.mark.django_db
+@override_settings(PRIVACY_POLICY_URL="", IMPRINT_URL="")
+def test_login_page_without_configured_urls_shows_no_legal_links(
+    client: Client,
+) -> None:
+    """Without configured URLs, no empty links may be rendered."""
+    content = client.get(reverse("admin:login")).content.decode()
+    assert "legal-links" not in content
+
+
+@pytest.mark.django_db
+@override_settings(PRIVACY_POLICY_URL=PRIVACY_POLICY_URL, IMPRINT_URL=IMPRINT_URL)
+def test_admin_footer_shows_legal_links(client: Client) -> None:
+    """The admin footer carries the links on every page of the admin."""
+    user = User.objects.create_superuser("legal-test", "legal@example.com", "password")
+    client.force_login(user)
+    content = client.get(reverse("admin:index")).content.decode()
+    assert PRIVACY_POLICY_URL in content
+    assert IMPRINT_URL in content
+
+
+def test_legal_menu_links_skips_unconfigured_urls() -> None:
+    """A link without a URL must not end up in the user menu."""
+    assert legal_menu_links("", "") == []
+    links = legal_menu_links(PRIVACY_POLICY_URL, "")
+    assert [link["url"] for link in links] == [PRIVACY_POLICY_URL]
+
+
+def test_legal_menu_links_open_in_new_window() -> None:
+    """Both links leave the admin, so they must not replace the current tab."""
+    links = legal_menu_links(PRIVACY_POLICY_URL, IMPRINT_URL)
+    assert [link["url"] for link in links] == [PRIVACY_POLICY_URL, IMPRINT_URL]
+    assert all(link["new_window"] for link in links)