faster is_valid_hashcharacter

lbrynet/blob/blob_file.py

@@ -18,13 +18,13 @@ from lbrynet.blob.writer import HashBlobWriter
 log = logging.getLogger(__name__)
 
 
-def is_valid_hashcharacter(char: str) -> bool:
-    return char in "0123456789abcdef"
-
-
 _hexmatch = re.compile("^[a-f,0-9]+$")
 
 
+def is_valid_hashcharacter(char: str) -> bool:
+    return len(char) == 1 and _hexmatch.match(char)
+
+
 def is_valid_blobhash(blobhash: str) -> bool:
     """Checks whether the blobhash is the correct length and contains only
     valid characters (0-9, a-f)
@@ -35,6 +35,7 @@ def is_valid_blobhash(blobhash: str) -> bool:
     """
     return len(blobhash) == blobhash_length and _hexmatch.match(blobhash)
 
+
 def encrypt_blob_bytes(key: bytes, iv: bytes, unencrypted: bytes) -> typing.Tuple[bytes, str]:
     cipher = Cipher(AES(key), modes.CBC(iv), backend=backend)
     padder = PKCS7(AES.block_size).padder()