Separating creation of decryption request from the actual retrieval flow, so that pre-serialized decryption requests can be used.

nucypher/characters/lawful.py

@@ -562,23 +562,14 @@ class Bob(Character):
 
         return cohort
 
-    def gather_decryption_shares(
-        self,
-        ritual_id: int,
-        cohort: List["Ursula"],
-        ciphertext: Ciphertext,
-        lingo: LingoList,
-        threshold: int,
-        variant: FerveoVariant,
-        context: Optional[dict] = None,
-    ) -> Dict[
-        ChecksumAddress, Union[DecryptionShareSimple, DecryptionSharePrecomputed]
-    ]:
-        if variant == FerveoVariant.PRECOMPUTED:
-            share_type = DecryptionSharePrecomputed
-        elif variant == FerveoVariant.SIMPLE:
-            share_type = DecryptionShareSimple
-
+    def make_decryption_request(
+            self,
+            ritual_id: int,
+            ciphertext: Ciphertext,
+            lingo: LingoList,
+            variant: FerveoVariant,
+            context: Optional[dict] = None,
+    ) -> ThresholdDecryptionRequest:
         conditions = Conditions(json.dumps(lingo))
         if context:
             context = Context(json.dumps(context))
@@ -589,6 +580,18 @@ class Bob(Character):
             conditions=conditions,
             context=context,
         )
+        return decryption_request
+
+    def get_decryption_shares_using_existing_decryption_request(self,
+                                                                decryption_request: ThresholdDecryptionRequest,
+                                                                variant: FerveoVariant,
+                                                                cohort: List["Ursula"],
+                                                                threshold: int,
+                                                                ):
+        if variant == FerveoVariant.PRECOMPUTED:
+            share_type = DecryptionSharePrecomputed
+        elif variant == FerveoVariant.SIMPLE:
+            share_type = DecryptionShareSimple
 
         decryption_request_mapping = {}
         for ursula in cohort:
@@ -614,6 +617,27 @@ class Bob(Character):
             gathered_shares[provider_address] = decryption_share
         return gathered_shares
 
+    def gather_decryption_shares(
+            self,
+            ritual_id: int,
+            cohort: List["Ursula"],
+            ciphertext: Ciphertext,
+            lingo: LingoList,
+            threshold: int,
+            variant: FerveoVariant,
+            context: Optional[dict] = None,
+    ) -> Dict[
+        ChecksumAddress, Union[DecryptionShareSimple, DecryptionSharePrecomputed]
+    ]:
+
+        decryption_request = self.make_decryption_request(ritual_id=ritual_id,
+                                                          ciphertext=ciphertext,
+                                                          lingo=lingo,
+                                                          variant=variant,
+                                                          context=context)
+        return self.get_decryption_shares_using_existing_decryption_request(decryption_request, variant, cohort,
+                                                                            threshold)
+
     def threshold_decrypt(self,
                           ritual_id: int,
                           ciphertext: Ciphertext,