Add a basic interop test for Go and Python peer IDs

tests/peer/test_interop.py

@@ -0,0 +1,43 @@
+import base64
+
+import Crypto.PublicKey.RSA as RSA
+
+from libp2p.crypto.pb import crypto_pb2 as pb
+from libp2p.crypto.rsa import RSAPrivateKey
+from libp2p.peer.id import ID
+
+# ``PRIVATE_KEY_PROTOBUF_SERIALIZATION`` is a protobuf holding an RSA private key.
+PRIVATE_KEY_PROTOBUF_SERIALIZATION = """
+CAAS4AQwggJcAgEAAoGBAL7w+Wc4VhZhCdM/+Hccg5Nrf4q9NXWwJylbSrXz/unFS24wyk6pEk0zi3W
+7li+vSNVO+NtJQw9qGNAMtQKjVTP+3Vt/jfQRnQM3s6awojtjueEWuLYVt62z7mofOhCtj+VwIdZNBo
+/EkLZ0ETfcvN5LVtLYa8JkXybnOPsLvK+PAgMBAAECgYBdk09HDM7zzL657uHfzfOVrdslrTCj6p5mo
+DzvCxLkkjIzYGnlPuqfNyGjozkpSWgSUc+X+EGLLl3WqEOVdWJtbM61fewEHlRTM5JzScvwrJ39t7o6
+CCAjKA0cBWBd6UWgbN/t53RoWvh9HrA2AW5YrT0ZiAgKe9y7EMUaENVJ8QJBAPhpdmb4ZL4Fkm4OKia
+NEcjzn6mGTlZtef7K/0oRC9+2JkQnCuf6HBpaRhJoCJYg7DW8ZY+AV6xClKrgjBOfERMCQQDExhnzu2
+dsQ9k8QChBlpHO0TRbZBiQfC70oU31kM1AeLseZRmrxv9Yxzdl8D693NNWS2JbKOXl0kMHHcuGQLMVA
+kBZ7WvkmPV3aPL6jnwp2pXepntdVnaTiSxJ1dkXShZ/VSSDNZMYKY306EtHrIu3NZHtXhdyHKcggDXr
+qkBrdgErAkAlpGPojUwemOggr4FD8sLX1ot2hDJyyV7OK2FXfajWEYJyMRL1Gm9Uk1+Un53RAkJneqp
+JGAzKpyttXBTIDO51AkEA98KTiROMnnU8Y6Mgcvr68/SMIsvCYMt9/mtwSBGgl80VaTQ5Hpaktl6Xbh
+VUt5Wv0tRxlXZiViCGCD1EtrrwTw==
+""".replace(
+    "\n", ""
+)
+
+EXPECTED_PEER_ID = "QmRK3JgmVEGiewxWbhpXLJyjWuGuLeSTMTndA1coMHEy5o"
+
+
+# NOTE: this test checks that we can recreate the expected peer id given a private key
+# serialization, taken from the Go implementation of libp2p.
+def test_peer_id_interop():
+    private_key_protobuf_bytes = base64.b64decode(PRIVATE_KEY_PROTOBUF_SERIALIZATION)
+    private_key_protobuf = pb.PrivateKey()
+    private_key_protobuf.ParseFromString(private_key_protobuf_bytes)
+
+    private_key_data = private_key_protobuf.data
+
+    private_key_impl = RSA.import_key(private_key_data)
+    private_key = RSAPrivateKey(private_key_impl)
+    public_key = private_key.get_public_key()
+
+    peer_id = ID.from_pubkey(public_key)
+    assert peer_id == EXPECTED_PEER_ID