Added some nonsense consensus rules to demonstrate a simpler plugin.

bigchaindb/consensus/silly.py

@@ -0,0 +1,21 @@
+import bigchaindb.exceptions as exceptions
+from bigchaindb.crypto import hash_data
+from bigchaindb.consensus import AbstractConsensusRules
+
+
+class SillyConsensusRules(AbstractConsensusRules):
+
+    @classmethod
+    def validate_transaction(cls, bigchain, transaction):
+        # I only like transactions whose timestamps are even.
+        if transaction['transaction']['timestamp'] % 2 != 0:
+            raise StandardError("Odd... very odd indeed.")
+        return transaction
+
+    @classmethod
+    def validate_block(cls, bigchain, transaction):
+        # I don't trust Alice, I think she's shady.
+        if block['block']['node_pubkey'] == '<ALICE_PUBKEY>':
+            raise StandardError("Alice is shady, everybody ignore her blocks!")
+
+        return block