Finishing the layup for which @michwill set me up vis a vis TreasureMaps being passed through Bob's controller.

nucypher/characters/control/interfaces.py

@@ -202,10 +202,13 @@ class BobInterface(CharacterPublicInterface):
                                               label=label)
 
         self.character.join_policy(label=label, alice_verifying_key=alice_verifying_key)
+
+
         plaintexts = self.character.retrieve(message_kit,
                                              enrico=enrico,
                                              alice_verifying_key=alice_verifying_key,
-                                             label=label)
+                                             label=label,
+                                             treasure_map=treasure_map)
 
         response_data = {'cleartexts': plaintexts}
         return response_data

nucypher/characters/lawful.py

@@ -17,7 +17,7 @@ along with nucypher.  If not, see <https://www.gnu.org/licenses/>.
 
 import json
 import time
-from base64 import b64encode
+from base64 import b64encode, b64decode
 from collections import OrderedDict
 from functools import partial
 from json.decoder import JSONDecodeError
@@ -679,13 +679,21 @@ class Bob(Character):
 
         hrac, map_id = self.construct_hrac_and_map_id(alice_verifying_key, label)
         if treasure_map is not None:
+            alice = Alice.from_public_keys(verifying_key=alice_verifying_key)
+            compass = self.make_compass_for_alice(alice)
+
             from nucypher.policy.collections import TreasureMap
 
+            # TODO: This LBYL is ugly and fraught with danger.
             if isinstance(treasure_map, bytes):
                 treasure_map = TreasureMap.from_bytes(treasure_map)
-                alice = Alice.from_public_keys(verifying_key=alice_verifying_key)
-                compass = self.make_compass_for_alice(alice)
-                treasure_map.orient(compass)
+
+            if isinstance(treasure_map, str):
+                tmap_bytes = treasure_map.encode()
+                b64decode(tmap_bytes)
+                treasure_map = TreasureMap.from_bytes(b64decode(tmap_bytes))
+
+            treasure_map.orient(compass)
             _unknown_ursulas, _known_ursulas, m = self.follow_treasure_map(treasure_map=treasure_map, block=True)
         else:
             _unknown_ursulas, _known_ursulas, m = self.follow_treasure_map(map_id=map_id, block=True)

tests/characters/control/blockchain/test_rpc_control_blockchain.py

@@ -145,6 +145,6 @@ def test_bob_rpc_character_control_retrieve_with_tmap(
             blockchain_alice.stamp,
             b'Wrong!')
     tmap_64 = b64encode(bytes(wrong_tmap)).decode()
-    params['treasure_map'] = tmap_64
+    request_data['params']['treasure_map'] = tmap_64
     with pytest.raises(TreasureMap.IsDisorienting):
         bob_rpc_controller.send(request_data)