Prettier DRF pages when using trusted proxy (#15579)

This is a rather hacky, but fixes the DRF pages when going through a
trusted proxy.

Notably: This is meant to primarily fix the DRF pages on downstream
builds while leaving the upstream to function as-is.

When using a trusted proxy, the DRF login and logout endpoints now
redirect to the Platform login page (which respects ?next) and logout
endpoint respectively.

The CSS and JS is inlined because the trusted proxy might only proxy
to /api/ and not /static/ which is a harder problem to solve.

Signed-off-by: Rick Elrod <rick@elrod.me>

3 files changed, 45 insertions, 4 deletions

diff --git a/awx/api/generics.py b/awx/api/generics.py
index 9e1698a61f..c71919b7be 100644
--- a/awx/api/generics.py
+++ b/awx/api/generics.py
@@ -14,7 +14,7 @@ from django.core.exceptions import FieldDoesNotExist
 from django.db import connection, transaction
 from django.db.models.fields.related import OneToOneRel
 from django.http import QueryDict
-from django.shortcuts import get_object_or_404
+from django.shortcuts import get_object_or_404, redirect
 from django.template.loader import render_to_string
 from django.utils.encoding import smart_str
 from django.utils.safestring import mark_safe
@@ -36,7 +36,7 @@ from awx_plugins.interfaces._temporary_private_licensing_api import detect_serve
 # django-ansible-base
 from ansible_base.rest_filters.rest_framework.field_lookup_backend import FieldLookupBackend
 from ansible_base.lib.utils.models import get_all_field_names
-from ansible_base.lib.utils.requests import get_remote_host
+from ansible_base.lib.utils.requests import get_remote_host, is_proxied_request
 from ansible_base.rbac.models import RoleEvaluation, RoleDefinition
 from ansible_base.rbac.permission_registry import permission_registry
 from ansible_base.jwt_consumer.common.util import validate_x_trusted_proxy_header
@@ -82,6 +82,12 @@ analytics_logger = logging.getLogger('awx.analytics.performance')
 
 class LoggedLoginView(auth_views.LoginView):
     def get(self, request, *args, **kwargs):
+        if is_proxied_request():
+            next = request.GET.get('next', "")
+            if next:
+                next = f"?next={next}"
+            return redirect(f"/{next}")
+
         # The django.auth.contrib login form doesn't perform the content
         # negotiation we've come to expect from DRF; add in code to catch
         # situations where Accept != text/html (or */*) and reply with
@@ -97,6 +103,15 @@ class LoggedLoginView(auth_views.LoginView):
         return super(LoggedLoginView, self).get(request, *args, **kwargs)
 
     def post(self, request, *args, **kwargs):
+        if is_proxied_request():
+            # Give a message, saying to login via AAP
+            return Response(
+                {
+                    'detail': _('Please log in via Platform Authentication.'),
+                },
+                status=status.HTTP_401_UNAUTHORIZED,
+            )
+
         ret = super(LoggedLoginView, self).post(request, *args, **kwargs)
         ip = get_remote_host(request)  # request.META.get('REMOTE_ADDR', None)
         if request.user.is_authenticated:
@@ -119,6 +134,12 @@ class LoggedLogoutView(auth_views.LogoutView):
     success_url_allowed_hosts = set(settings.LOGOUT_ALLOWED_HOSTS.split(",")) if settings.LOGOUT_ALLOWED_HOSTS else set()
 
     def dispatch(self, request, *args, **kwargs):
+        if is_proxied_request():
+            # 1) We intentionally don't obey ?next= here, just always redirect to platform login
+            # 2) Hack to prevent rewrites of Location header
+            qs = "?__gateway_no_rewrite__=1&next=/"
+            return redirect(f"/api/gateway/v1/logout/{qs}")
+
         original_user = getattr(request, 'user', None)
         ret = super(LoggedLogoutView, self).dispatch(request, *args, **kwargs)
         current_user = getattr(request, 'user', None)
diff --git a/awx/settings/defaults.py b/awx/settings/defaults.py
index bf1e6e5727..e535cf10dd 100644
--- a/awx/settings/defaults.py
+++ b/awx/settings/defaults.py
@@ -320,6 +320,10 @@ TEMPLATES = [
                 'social_django.context_processors.login_redirect',
             ],
             'builtins': ['awx.main.templatetags.swagger'],
+            'libraries': {
+                "ansible_base.lib.templatetags.requests": "ansible_base.lib.templatetags.requests",
+                "ansible_base.lib.templatetags.util": "ansible_base.lib.templatetags.util",
+            },
         },
         'DIRS': [
             os.path.join(BASE_DIR, 'templates'),
diff --git a/awx/templates/rest_framework/api.html b/awx/templates/rest_framework/api.html
index fbcfe97b30..edfb721efd 100644
--- a/awx/templates/rest_framework/api.html
+++ b/awx/templates/rest_framework/api.html
@@ -1,11 +1,19 @@
 {% extends 'rest_framework/base.html' %}
-{% load i18n static %}
+{% load i18n static ansible_base.lib.templatetags.requests ansible_base.lib.templatetags.util %}
 
 {% block title %}{{ name }} · {% trans 'AWX REST API' %}{% endblock %}
 
 {% block bootstrap_theme %}
+  {% is_proxied_request as proxied %}
   <link rel="stylesheet" type="text/css" href="{% static 'rest_framework/css/bootstrap.min.css' %}" />
+  {% if proxied %}
+  <style>
+    {# inline_file from DAB #}
+    {% inline_file "static/api/api.css" True %}
+  </style>
+  {% else %}
   <link rel="stylesheet" type="text/css" href="{% static 'api/api.css' %}?v={{tower_version}}" />
+  {% endif %}
 {% endblock %}
 
 {% block style %}
@@ -24,7 +32,6 @@
           <span class="icon-bar"></span>
         </button>
         <a class="navbar-brand" href="{% url 'api:api_root_view' %}">
-          <img class="logo" src="{% static 'media/logo-header.svg' %}">
           <span>{% trans 'REST API' %}</span>
         </a>
         <a class="navbar-title" href="{{ request.get_full_path }}">
@@ -74,5 +81,14 @@
   <a class="toggle-description js-tooltip" href="#" title="Show/Hide Description"><span class="glyphicon glyphicon-question-sign"></span></a>
 </div>
 {{ block.super }}
+
+{% is_proxied_request as proxied %}
+{% if proxied %}
+<script>
+  {# inline_file from DAB #}
+  {% inline_file "static/api/api.js" True %}
+</script>
+{% else %}
 <script src="{% static 'api/api.js' %}?v={{tower_version}}"></script>
+{% endif %}
 {% endblock %}