relay: add support for nodeinfo protocol

relay/__init__.py

@@ -27,3 +27,4 @@ from . import database
 from . import actor
 from . import webfinger
 from . import default
+from . import nodeinfo

relay/nodeinfo.py

@@ -0,0 +1,60 @@
+import urllib.parse
+
+import aiohttp.web
+
+from . import app
+from .database import DATABASE
+
+
+nodeinfo_template = {
+    # XXX - is this valid for a relay?
+    'openRegistrations': True,
+    'protocols': ['activitypub'],
+    'services': {
+        'inbound': [],
+        'outbound': []
+    },
+    'software': {
+        'name': 'ActivityRelay',
+        'version': '0.1'
+    },
+    'usage': {
+        'localPosts': 0,
+        'users': {
+            'total': 1
+        }
+    },
+    'version': '2.0'
+}
+
+
+def get_peers():
+    global DATABASE
+
+    return [urllib.parse.urlsplit(inbox).hostname for inbox in DATABASE.get('relay-list', [])]
+
+
+async def nodeinfo_2_0(request):
+    data = nodeinfo_template.copy()
+    data['metadata'] = {
+        'peers': get_peers()
+    }
+    return aiohttp.web.json_response(data)
+
+
+app.router.add_get('/nodeinfo/2.0.json', nodeinfo_2_0)
+
+
+async def nodeinfo_wellknown(request):
+    data = {
+        'links': [
+             {
+                 'rel': 'http://nodeinfo.diaspora.software/ns/schema/2.0',
+                 'href': 'https://{}/nodeinfo/2.0.json'.format(request.host)
+             }
+        ]
+    }
+    return aiohttp.web.json_response(data)
+
+
+app.router.add_get('/.well-known/nodeinfo', nodeinfo_wellknown)