Be more strict with chain field in Schema.

Update tests accordingly.

nucypher/policy/conditions/evm.py

@@ -11,6 +11,7 @@ from typing import (
 from eth_typing import ChecksumAddress
 from eth_utils import to_checksum_address
 from marshmallow import ValidationError, fields, post_load, validate, validates_schema
+from marshmallow.validate import OneOf
 from web3 import HTTPProvider, Web3
 from web3.contract.contract import ContractFunction
 from web3.middleware import geth_poa_middleware
@@ -137,7 +138,9 @@ class RPCCondition(AccessControlCondition):
         condition_type = fields.Str(
             validate=validate.Equal(ConditionType.RPC.value), required=True
         )
-        chain = fields.Int(required=True)
+        chain = fields.Int(
+            required=True, strict=True, validate=OneOf(_CONDITION_CHAINS)
+        )
         method = fields.Str(required=True)
         parameters = fields.List(fields.Field, attribute="parameters", required=False)
         return_value_test = fields.Nested(

nucypher/policy/conditions/time.py

@@ -1,8 +1,9 @@
 from typing import Any, List, Optional
 
 from marshmallow import fields, post_load, validate
+from marshmallow.validate import Equal, OneOf
 
-from nucypher.policy.conditions.evm import RPCCondition
+from nucypher.policy.conditions.evm import _CONDITION_CHAINS, RPCCondition
 from nucypher.policy.conditions.exceptions import InvalidCondition
 from nucypher.policy.conditions.lingo import ConditionType, ReturnValueTest
 from nucypher.policy.conditions.utils import CamelCaseSchema
@@ -18,8 +19,12 @@ class TimeCondition(RPCCondition):
             validate=validate.Equal(ConditionType.TIME.value), required=True
         )
         name = fields.Str(required=False)
-        chain = fields.Int(required=True)
-        method = fields.Str(dump_default="blocktime", required=True)
+        chain = fields.Int(
+            required=True, strict=True, validate=OneOf(_CONDITION_CHAINS)
+        )
+        method = fields.Str(
+            dump_default="blocktime", required=True, validate=Equal("blocktime")
+        )
         return_value_test = fields.Nested(
             ReturnValueTest.ReturnValueTestSchema(), required=True
         )

tests/unit/conditions/test_rpc_condition.py

@@ -96,6 +96,16 @@ def test_rpc_condition_schema_validation(rpc_condition):
         del condition_dict["returnValueTest"]
         RPCCondition.validate(condition_dict)
 
+    with pytest.raises(InvalidCondition):
+        # chain id not an integer
+        condition_dict["chain"] = str(TESTERCHAIN_CHAIN_ID)
+        RPCCondition.validate(condition_dict)
+
+    with pytest.raises(InvalidCondition):
+        # chain id not a permitted chain
+        condition_dict["chain"] = 90210  # Beverly Hills Chain :)
+        RPCCondition.validate(condition_dict)
+
 
 def test_rpc_condition_repr(rpc_condition):
     rpc_condition_str = f"{rpc_condition}"

tests/unit/conditions/test_time_condition.py

@@ -24,6 +24,22 @@ def test_invalid_time_condition():
             method="time_after_time",
         )
 
+    # invalid chain id
+    with pytest.raises(InvalidCondition):
+        _ = TimeCondition(
+            return_value_test=ReturnValueTest(">", 0),
+            chain="mychain",
+            method="time_after_time",
+        )
+
+    # chain id not permitted
+    with pytest.raises(InvalidCondition):
+        _ = TimeCondition(
+            return_value_test=ReturnValueTest(">", 0),
+            chain=90210,  # Beverly Hills Chain :)
+            method="time_after_time",
+        )
+
 
 def test_time_condition_schema_validation(time_condition):
     condition_dict = time_condition.to_dict()
@@ -47,6 +63,21 @@ def test_time_condition_schema_validation(time_condition):
         del condition_dict["returnValueTest"]
         TimeCondition.validate(condition_dict)
 
+    with pytest.raises(InvalidCondition):
+        # invalid method name
+        condition_dict["method"] = "my_blocktime"
+        TimeCondition.validate(condition_dict)
+
+    with pytest.raises(InvalidCondition):
+        # chain id not an integer
+        condition_dict["chain"] = str(TESTERCHAIN_CHAIN_ID)
+        TimeCondition.validate(condition_dict)
+
+    with pytest.raises(InvalidCondition):
+        # chain id not a permitted chain
+        condition_dict["chain"] = 90210  # Beverly Hills Chain :)
+        TimeCondition.validate(condition_dict)
+
 
 @pytest.mark.parametrize(
     "invalid_value", ["0x123456", 10.15, [1], [1, 2, 3], [True, [1, 2], "0x0"]]