Merge pull request #364 from ianco/read-only-ledger

Read only ledger flag

aries_cloudagent/commands/provision.py

@@ -48,6 +48,10 @@ def execute(argv: Sequence[str] = None):
     settings = get_settings(args)
     common_config(settings)
 
+    # provision needs write access to the ledger
+    # (override if specified otherwise)
+    settings["ledger.read_only"] = False
+
     loop = asyncio.get_event_loop()
     loop.run_until_complete(provision(settings))
 

aries_cloudagent/commands/start.py

@@ -47,6 +47,9 @@ def execute(argv: Sequence[str] = None):
     settings = get_settings(args)
     common_config(settings)
 
+    # set ledger to read only if explicitely specified
+    settings["ledger.read_only"] = settings.get("read_only_ledger", False)
+
     # Support WEBHOOK_URL environment variable
     webhook_url = os.environ.get("WEBHOOK_URL")
     if webhook_url:

aries_cloudagent/config/argparse.py

@@ -377,6 +377,28 @@ def add_arguments(self, parser: ArgumentParser):
             storage engine. This storage interface is used to store internal state.\
             Supported internal storage types are 'basic' (memory) and 'indy'.",
         )
+        parser.add_argument(
+            "-e",
+            "--endpoint",
+            type=str,
+            nargs="+",
+            metavar="<endpoint>",
+            help="Specifies the endpoints to put into DIDDocs\
+            to inform other agents of where they should send messages destined\
+            for this agent. Each endpoint could be one of the specified inbound\
+            transports for this agent, or the endpoint could be that of\
+            another agent (e.g. 'https://example.com/agent-endpoint') if the\
+            routing of messages to this agent by a mediator is configured.\
+            The first endpoint specified will be used in invitations.\
+            The endpoints are used in the formation of a connection\
+            with another agent.",
+        )
+        parser.add_argument(
+            "--read-only-ledger",
+            action="store_true",
+            help="Sets ledger to read-only to prevent updates.\
+            Default: false.",
+        )
 
     def get_settings(self, args: Namespace) -> dict:
         """Extract general settings."""
@@ -385,6 +407,11 @@ def get_settings(self, args: Namespace) -> dict:
             settings["external_plugins"] = args.external_plugins
         if args.storage_type:
             settings["storage.type"] = args.storage_type
+        if args.endpoint:
+            settings["default_endpoint"] = args.endpoint[0]
+            settings["additional_endpoints"] = args.endpoint[1:]
+        if args.read_only_ledger:
+            settings["read_only_ledger"] = True
         return settings
 
 
@@ -590,22 +617,6 @@ def add_arguments(self, parser: ArgumentParser):
             multiple times to supoort multiple transport types. Supported outbound\
             transport types are 'http' and 'ws'.",
         )
-        parser.add_argument(
-            "-e",
-            "--endpoint",
-            type=str,
-            nargs="+",
-            metavar="<endpoint>",
-            help="Specifies the endpoints to put into DIDDocs\
-            to inform other agents of where they should send messages destined\
-            for this agent. Each endpoint could be one of the specified inbound\
-            transports for this agent, or the endpoint could be that of\
-            another agent (e.g. 'https://example.com/agent-endpoint') if the\
-            routing of messages to this agent by a mediator is configured.\
-            The first endpoint specified will be used in invitations.\
-            The endpoints are used in the formation of a connection\
-            with another agent.",
-        )
         parser.add_argument(
             "-l",
             "--label",
@@ -621,7 +632,6 @@ def add_arguments(self, parser: ArgumentParser):
             metavar="<message-size>",
             help="Set the maximum size in bytes for inbound agent messages.",
         )
-
         parser.add_argument(
             "--enable-undelivered-queue",
             action="store_true",
@@ -637,9 +647,6 @@ def get_settings(self, args: Namespace):
         settings["transport.outbound_configs"] = args.outbound_transports
         settings["transport.enable_undelivered_queue"] = args.enable_undelivered_queue
 
-        if args.endpoint:
-            settings["default_endpoint"] = args.endpoint[0]
-            settings["additional_endpoints"] = args.endpoint[1:]
         if args.label:
             settings["default_label"] = args.label
         if args.max_message_size:

aries_cloudagent/config/tests/test_argparse.py

@@ -40,25 +40,16 @@ async def test_transport_settings(self):
                 "80",
                 "--outbound-transport",
                 "http",
-                "-e",
-                "http://default.endpoint/",
-                "ws://alternate.endpoint/",
             ]
         )
 
         assert result.inbound_transports == [["http", "0.0.0.0", "80"]]
         assert result.outbound_transports == ["http"]
-        assert result.endpoint == [
-            "http://default.endpoint/",
-            "ws://alternate.endpoint/",
-        ]
 
         settings = group.get_settings(result)
 
         assert settings.get("transport.inbound_configs") == [["http", "0.0.0.0", "80"]]
         assert settings.get("transport.outbound_configs") == ["http"]
-        assert settings.get("default_endpoint") == "http://default.endpoint/"
-        assert settings.get("additional_endpoints") == ["ws://alternate.endpoint/"]
 
     def test_bytesize(self):
         bs = ByteSize()

aries_cloudagent/ledger/indy.py

@@ -88,6 +88,7 @@ def __init__(
         keepalive: int = 0,
         cache: BaseCache = None,
         cache_duration: int = 600,
+        read_only: bool = False,
     ):
         """
         Initialize an IndyLedger instance.
@@ -113,6 +114,7 @@ def __init__(
         self.pool_name = pool_name
         self.taa_acceptance = None
         self.taa_cache = None
+        self.read_only = read_only
 
         if wallet.WALLET_TYPE != "indy":
             raise LedgerConfigError("Wallet type is not 'indy'")
@@ -314,6 +316,11 @@ async def send_schema(
         if schema_id:
             self.logger.warning("Schema already exists on ledger. Returning ID.")
         else:
+            if self.read_only:
+                raise LedgerError(
+                    "Error cannot write schema when ledger is in read only mode"
+                )
+
             with IndyErrorHandler("Exception when creating schema definition"):
                 schema_id, schema_json = await indy.anoncreds.issuer_create_schema(
                     public_info.did,
@@ -556,6 +563,11 @@ async def cred_def_in_wallet(wallet_handle, cred_def_id) -> bool:
             except IndyError as error:
                 raise IndyErrorHandler.wrap_error(error) from error
             else:  # created cred def in wallet OK
+                if self.read_only:
+                    raise LedgerError(
+                        "Error cannot write cred def when ledger is in read only mode"
+                    )
+
                 wallet_cred_def = json.loads(credential_definition_json)
                 with IndyErrorHandler("Exception when building cred def request"):
                     request_json = await indy.ledger.build_cred_def_request(
@@ -714,6 +726,11 @@ async def update_endpoint_for_did(self, did: str, endpoint: str) -> bool:
         """
         exist_endpoint = await self.get_endpoint_for_did(did)
         if exist_endpoint != endpoint:
+            if self.read_only:
+                raise LedgerError(
+                    "Error cannot update endpoint when ledger is in read only mode"
+                )
+
             nym = self.did_to_nym(did)
             attr_json = json.dumps({"endpoint": {"endpoint": endpoint}})
             with IndyErrorHandler("Exception when building attribute request"):
@@ -736,6 +753,11 @@ async def register_nym(
             alias: Human-friendly alias to assign to the DID.
             role: For permissioned ledgers, what role should the new DID have.
         """
+        if self.read_only:
+            raise LedgerError(
+                "Error cannot register nym when ledger is in read only mode"
+            )
+
         public_info = await self.wallet.get_public_did()
         public_did = public_info.did if public_info else None
         r = await indy.ledger.build_nym_request(public_did, did, verkey, alias, role)

aries_cloudagent/ledger/provider.py

@@ -20,13 +20,17 @@ async def provide(self, settings: BaseSettings, injector: BaseInjector):
 
         pool_name = settings.get("ledger.pool_name", "default")
         keepalive = int(settings.get("ledger.keepalive", 5))
+        read_only = bool(settings.get("ledger.read_only", False))
+        if read_only:
+            LOGGER.error("Note: setting ledger to read-only mode")
         wallet = await injector.inject(BaseWallet)
         ledger = None
 
         if wallet.WALLET_TYPE == "indy":
             IndyLedger = ClassLoader.load_class(self.LEDGER_CLASSES["indy"])
             cache = await injector.inject(BaseCache, required=False)
-            ledger = IndyLedger(pool_name, wallet, keepalive=keepalive, cache=cache)
+            ledger = IndyLedger(pool_name, wallet, keepalive=keepalive, cache=cache,
+                                read_only=read_only)
 
             genesis_transactions = settings.get("ledger.genesis_transactions")
             if genesis_transactions: