Add WebFinger support and refactor some of the request manip stuff

wellknowns/urls.py

@@ -7,4 +7,5 @@ urlpatterns = [
     url(r'^keybase.txt$', views.keybase, name='keybase'),
     url(r'^host-meta$', views.host_meta_xml, name='host-meta'),
     url(r'^host-meta.json$', views.host_meta_json, name='host-meta.json'),
+    url(r'^webfinger$', views.webfinger, name='webfinger'),
 ]

wellknowns/views/__init__.py

@@ -1,2 +1,3 @@
 from .static import keybase
 from .host_meta import host_meta_xml, host_meta_json
+from .webfinger import webfinger

wellknowns/views/host_meta.py

@@ -1,12 +1,15 @@
 from django.http import HttpResponse
-from django.conf import settings
-from lemoncurry.templatetags.lemoncurry_tags import get_package_json
+from django.urls import reverse
+from lemoncurry.utils import load_package_json, origin
+from urllib.parse import urljoin
 from xrd import XRD, Attribute, Element, Link
 
 
-def add_links(dest):
-    package = get_package_json()
+def add_links(request, dest):
+    base = origin(request)
+    package = load_package_json()
     links = (
+        Link(rel='lrdd', template=urljoin(base, reverse('wellknowns:webfinger') + '?resource={uri}')),
         Link(rel='license', href='https://creativecommons.org/licenses/by-sa/4.0/'),
         Link(rel='code-repository', href=package['repository']),
     )
@@ -17,7 +20,7 @@ def host_meta(request):
     h = XRD()
     h.attributes.append(Attribute('xmlns:hm', 'http://host-meta.net/ns/1.0'))
     h.elements.append(Element('hm:Host', request.META['HTTP_HOST']))
-    add_links(h.links)
+    add_links(request, h.links)
     return h
 
 

wellknowns/views/webfinger.py

@@ -0,0 +1,43 @@
+from django.http import HttpResponseBadRequest, HttpResponseNotFound
+from django.http import JsonResponse
+from users.models import User
+from django.shortcuts import get_object_or_404
+from urllib.parse import urlparse, urljoin
+from lemoncurry.utils import origin
+
+AVATAR = 'http://webfinger.net/rel/avatar'
+PROFILE_PAGE = 'http://webfinger.net/rel/profile-page'
+
+
+def webfinger(request):
+    if 'resource' not in request.GET:
+        return HttpResponseBadRequest('resource parameter missing')
+    try:
+        resource = urlparse(request.GET['resource'])
+    except ValueError:
+        return HttpResponseBadRequest('resource parameter malformed')
+
+    if resource.scheme in ('mailto', 'acct', 'xmpp'):
+        user = get_object_or_404(User, email=resource.path)
+    elif resource.scheme in ('http', 'https'):
+        user = get_object_or_404(User, pk=1)
+    else:
+        return HttpResponseNotFound('resource not found on this server')
+
+    base = origin(request)
+
+    def link(rel, href, type):
+        return {'rel': rel, 'href': urljoin(base, href), 'type': type}
+
+    info = {
+        'subject': 'acct:' + user.email,
+        'aliases': (
+            urljoin(base, user.url),
+            'mailto:' + user.email,
+        ),
+        'links': (
+            link(rel=AVATAR, href=user.avatar.url, type='image/png'),
+            link(rel=PROFILE_PAGE, href=user.url, type='text/html'),
+        ),
+    }
+    return JsonResponse(info, content_type='application/jrd+json')