Merge pull request #242 from andrewwhitehead/cred-req-reuse

Reuse credential offers and requests when possible
hyperledger · Oct 30, 2019 · ca34806 · ca34806
2 parents f5447cd + ba8e8bc
commit ca34806
Show file tree

Hide file tree

Showing 11 changed files with 1,067 additions and 548 deletions.
diff --git a/aries_cloudagent/messaging/credentials/manager.py b/aries_cloudagent/messaging/credentials/manager.py
@@ -65,10 +65,18 @@ async def create_offer(
 
         """
 
-        issuer: BaseIssuer = await self.context.inject(BaseIssuer)
-        credential_offer = await issuer.create_credential_offer(
-            credential_definition_id
-        )
+        cache_key = f"credential_offer::{credential_definition_id}"
+        cached = await CredentialExchange.get_cached_key(self.context, cache_key)
+        if cached:
+            credential_offer = cached["offer"]
+        else:
+            issuer: BaseIssuer = await self.context.inject(BaseIssuer)
+            credential_offer = await issuer.create_credential_offer(
+                credential_definition_id
+            )
+            await CredentialExchange.set_cached_key(
+                self.context, cache_key, {"offer": credential_offer}, 3600
+            )
 
         credential_offer_message = CredentialOffer(
             offer_json=json.dumps(credential_offer)
@@ -146,19 +154,41 @@ async def create_request(
                 credential_exchange_record.credential_exchange_id,
             )
         else:
-            ledger: BaseLedger = await self.context.inject(BaseLedger)
-            async with ledger:
-                credential_definition = await ledger.get_credential_definition(
-                    credential_definition_id
-                )
-
-            holder: BaseHolder = await self.context.inject(BaseHolder)
-            (
-                credential_exchange_record.credential_request,
-                credential_exchange_record.credential_request_metadata,
-            ) = await holder.create_credential_request(
-                credential_offer, credential_definition, did
+            nonce = credential_offer["nonce"]
+            cache_key = (
+                f"credential_request::{credential_definition_id}::{did}::{nonce}"
             )
+            cached = await CredentialExchange.get_cached_key(self.context, cache_key)
+            if cached:
+                (
+                    credential_exchange_record.credential_request,
+                    credential_exchange_record.credential_request_metadata,
+                ) = (cached["request"], cached["metadata"])
+            else:
+                ledger: BaseLedger = await self.context.inject(BaseLedger)
+                async with ledger:
+                    credential_definition = await ledger.get_credential_definition(
+                        credential_definition_id
+                    )
+
+                holder: BaseHolder = await self.context.inject(BaseHolder)
+                (
+                    credential_exchange_record.credential_request,
+                    credential_exchange_record.credential_request_metadata,
+                ) = await holder.create_credential_request(
+                    credential_offer, credential_definition, did
+                )
+                await CredentialExchange.set_cached_key(
+                    self.context,
+                    cache_key,
+                    {
+                        "request": credential_exchange_record.credential_request,
+                        "metadata": (
+                            credential_exchange_record.credential_request_metadata
+                        ),
+                    },
+                    7200,
+                )
 
         credential_request_message = CredentialRequest(
             request=json.dumps(credential_exchange_record.credential_request)

diff --git a/aries_cloudagent/messaging/issue_credential/v1_0/handlers/credential_offer_handler.py b/aries_cloudagent/messaging/issue_credential/v1_0/handlers/credential_offer_handler.py
@@ -1,7 +1,5 @@
 """Basic message handler."""
 
-
-from .....storage.error import StorageNotFoundError
 from ....base_handler import (
     BaseHandler,
     BaseResponder,
@@ -10,8 +8,6 @@
 )
 from ..manager import CredentialManager
 from ..messages.credential_offer import CredentialOffer
-from ..messages.credential_proposal import CredentialProposal
-from ..models.credential_exchange import V10CredentialExchange
 
 
 class CredentialOfferHandler(BaseHandler):
@@ -38,43 +34,7 @@ async def handle(self, context: RequestContext, responder: BaseResponder):
 
         credential_manager = CredentialManager(context)
 
-        indy_offer = context.message.indy_offer(0)
-        credential_proposal_dict = CredentialProposal(
-            comment=context.message.comment,
-            credential_proposal=context.message.credential_preview,
-            cred_def_id=indy_offer["cred_def_id"],
-            schema_id=indy_offer["schema_id"],
-        ).serialize()
-
-        # Get credential exchange record (holder sent proposal first)
-        # or create it (issuer sent offer first)
-        try:
-            (
-                credential_exchange_record
-            ) = await V10CredentialExchange.retrieve_by_tag_filter(
-                context,
-                {"thread_id": context.message._thread_id},
-                {"connection_id": context.connection_record.connection_id},
-            )
-            credential_exchange_record.credential_proposal_dict = (
-                credential_proposal_dict
-            )
-        except StorageNotFoundError:  # issuer sent this offer free of any proposal
-            credential_exchange_record = V10CredentialExchange(
-                connection_id=context.connection_record.connection_id,
-                thread_id=context.message._thread_id,
-                initiator=V10CredentialExchange.INITIATOR_EXTERNAL,
-                role=V10CredentialExchange.ROLE_HOLDER,
-                credential_definition_id=indy_offer["cred_def_id"],
-                schema_id=indy_offer["schema_id"],
-                credential_proposal_dict=credential_proposal_dict,
-            )
-
-        credential_exchange_record.credential_offer = indy_offer
-
-        credential_exchange_record = await credential_manager.receive_offer(
-            credential_exchange_record
-        )
+        credential_exchange_record = await credential_manager.receive_offer()
 
         # If auto respond is turned on, automatically reply with credential request
         if context.settings.get("debug.auto_respond_credential_offer"):