From ae68cd33da7f058340af45168db0e093c84582ca Mon Sep 17 00:00:00 2001
From: Sergi Delgado Segura <sergi.delgado.s@gmail.com>
Date: Fri, 27 Mar 2020 16:41:19 +0100
Subject: [PATCH] Captures TypeErrors in Cryptographer.get_compressed_pk and
 adds unit tests

---
 common/cryptographer.py                | 11 ++++++++---
 test/common/unit/test_cryptographer.py | 24 ++++++++++++++++++++++++
 2 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/common/cryptographer.py b/common/cryptographer.py
index f5427e7..5414fda 100644
--- a/common/cryptographer.py
+++ b/common/cryptographer.py
@@ -315,7 +315,7 @@ class Cryptographer:
             if "failed to recover ECDSA public key" in str(e):
                 logger.error("Cannot recover public key from signature".format(type(rsig_recid)))
             else:
-                logger.error("Unknown exception", error=e)
+                logger.error("Unknown exception", error=str(e))
 
             return None
 
@@ -334,7 +334,6 @@ class Cryptographer:
 
         return pk.point() == rpk.point()
 
-    # TODO: UNITTEST
     @staticmethod
     def get_compressed_pk(pk):
         """
@@ -351,4 +350,10 @@ class Cryptographer:
             logger.error("The received data is not a PublicKey object")
             return None
 
-        return hexlify(pk.format(compressed=True)).decode("utf-8")
+        try:
+            compressed_pk = pk.format(compressed=True)
+            return hexlify(compressed_pk).decode("utf-8")
+
+        except TypeError as e:
+            logger.error("PublicKey has invalid initializer", error=str(e))
+            return None
diff --git a/test/common/unit/test_cryptographer.py b/test/common/unit/test_cryptographer.py
index d5983f5..ddbb707 100644
--- a/test/common/unit/test_cryptographer.py
+++ b/test/common/unit/test_cryptographer.py
@@ -255,3 +255,27 @@ def test_verify_pk_wrong():
     rpk = Cryptographer.recover_pk(message, zbase32_sig)
 
     assert not Cryptographer.verify_rpk(sk2.public_key, rpk)
+
+
+def test_get_compressed_pk():
+    sk, pk = generate_keypair()
+    compressed_pk = Cryptographer.get_compressed_pk(pk)
+
+    assert isinstance(compressed_pk, str) and len(compressed_pk) == 66
+    assert compressed_pk[:2] in ["02", "03"]
+
+
+def test_get_compressed_pk_wrong_key():
+    # pk should be properly initialized. Initializing from int will case it to not be recoverable
+    pk = PublicKey(0)
+    compressed_pk = Cryptographer.get_compressed_pk(pk)
+
+    assert compressed_pk is None
+
+
+def test_get_compressed_pk_wrong_type():
+    # Passing a value that is not a PublicKey will make it to fail too
+    pk = get_random_value_hex(33)
+    compressed_pk = Cryptographer.get_compressed_pk(pk)
+
+    assert compressed_pk is None