Require decompressed WARCs with warc-tiny

warc-tiny

@@ -13,6 +13,7 @@
 #  warc-tiny verify FILES  --  verify the integrity of a WARC by comparing the digests
 
 import base64
+import contextlib
 import enum
 import gzip
 import hashlib
@@ -122,11 +123,20 @@ class EndOfRecord(Event):
 	pass
 
 
+@contextlib.contextmanager
+def open_warc(f):
+	if hasattr(f, 'read'):
+		yield f
+	else:
+		with open(f, 'rb') as fp:
+			yield fp
+
+
 def iter_warc(f):
 	# Yields Events
 	# BeginOfRecord's rawData does not include the CRLF CRLF at the end of the headers, and WARCBlockChunk does not contain the CRLF CRLF after the block either.
 
-	with gzip.open(f, 'rb') as fp:
+	with open_warc(f) as fp:
 		buf = b''
 		while True:
 			# Read WARC header
@@ -526,6 +536,8 @@ def main():
 
 	try:
 		for f in files:
+			if f.endswith('.warc.gz') or f.endswith('.warc.zst'):
+				print(f'Warning: warc-tiny does not support decompressing WARCs like {f}. Please use zcat/zstdcat/zstdwarccat and pipe the decompressed stream into warc-tiny instead.', file = sys.stderr)
 			print('Info: processing {}'.format(f), file = sys.stderr)
 			processor.process_event(NewFile(f))
 			if f == '-':