Code cleanup

fedireads/api.py

@@ -1,5 +1,19 @@
+''' api utilties '''
+from base64 import b64encode
+from Crypto.PublicKey import RSA
+from Crypto.Signature import pkcs1_15
+from Crypto.Hash import SHA256
+from datetime import datetime
+import json
+import requests
+
+from fedireads import models
+from fedireads import incoming
+from fedireads.settings import DOMAIN
+
+
 def get_or_create_remote_user(actor):
-    ''' wow, a foreigner '''
+    ''' look up a remote user or add them '''
     try:
         user = models.User.objects.get(actor=actor)
     except models.User.DoesNotExist:
@@ -13,3 +27,56 @@ def get_or_create_remote_user(actor):
         )
     return user
 
+
+def get_recipients(user, post_privacy, direct_recipients=None):
+    ''' deduplicated list of recipients '''
+    recipients = direct_recipients or []
+
+    followers = user.followers.all()
+    if post_privacy == 'public':
+        # post to public shared inboxes
+        shared_inboxes = set(u.shared_inbox for u in followers)
+        recipients += list(shared_inboxes)
+        # TODO: direct to anyone who's mentioned
+    if post_privacy == 'followers':
+        # don't send it to the shared inboxes
+        inboxes = set(u.inbox for u in followers)
+        recipients += list(inboxes)
+    # if post privacy is direct, we just have direct recipients,
+    # which is already set. hurray
+    return recipients
+
+
+def broadcast(sender, action, recipients):
+    ''' send out an event '''
+    for recipient in recipients:
+        # TODO: error handling
+        sign_and_send(sender, action, recipient)
+
+
+def sign_and_send(sender, action, destination):
+    ''' crpyto whatever and http junk '''
+    inbox_fragment = sender.inbox.replace('https://%s' % DOMAIN, '')
+    now = datetime.utcnow().isoformat()
+    message_to_sign = '''(request-target): post %s
+host: https://%s
+date: %s''' % (inbox_fragment, DOMAIN, now)
+    signer = pkcs1_15.new(RSA.import_key(sender.private_key))
+    signed_message = signer.sign(SHA256.new(message_to_sign.encode('utf8')))
+
+    signature = 'keyId="%s",' % sender.localname
+    signature += 'headers="(request-target) host date",'
+    signature += 'signature="%s"' % b64encode(signed_message)
+    response = requests.post(
+        destination,
+        data=json.dumps(action),
+        headers={
+            'Date': now,
+            'Signature': signature,
+            'Host': DOMAIN,
+        },
+    )
+    if not response.ok:
+        response.raise_for_status()
+    incoming.handle_response(response)
+