Add ia-verify-file

ia-verify-file

@@ -0,0 +1,64 @@
+#!/usr/bin/env python3
+import http.client
+import json
+import string
+import sys
+import xml.etree.ElementTree
+
+
+if len(sys.argv[1:]) != 3:
+	print('Usage: ia-verify-file ITEM FILENAME SHA1', file = sys.stderr)
+	print('Verifies that FILENAME is present in ITEM (on all servers) and has hash SHA1', file = sys.stderr)
+	sys.exit(1)
+item, filename, sha1 = sys.argv[1:]
+
+if len(item) > 100 or item[0] not in (string.ascii_letters + string.digits) or item[1:].strip(string.ascii_letters + string.digits + '_-.') != '':
+	print('Invalid identifier', file = sys.stderr)
+	sys.exit(1)
+
+# Fetch https://archive.org/metadata/ITEM to get the two servers that store the item
+conn = http.client.HTTPSConnection('archive.org')
+conn.request('GET', f'/metadata/{item}')
+r = conn.getresponse()
+if r.status != 200:
+	print(f'Error fetching item metadata: {r.status} {r.reason}', file = sys.stderr)
+	sys.exit(1)
+o = json.loads(r.read())
+if not o:
+	print(f'Empty item metadata returned (item might not exist)', file = sys.stderr)
+	sys.exit(1)
+if 'workable_servers' not in o or 'dir' not in o:
+	print(f'Malformed metadata returned: {o!r}', file = sys.stderr)
+	sys.exit(1)
+
+if len(o['workable_servers']) < 2:
+	print(f'Not enough servers: {o["workable_servers"]!r}', file = sys.stderr)
+	sys.exit(1)
+
+# Fetch _files.xml from each server and compare hash
+for server in o['workable_servers']:
+	conn = http.client.HTTPSConnection(server)
+	conn.request('GET', f'{o["dir"]}/{item}_files.xml')
+	r = conn.getresponse()
+	if r.status != 200:
+		print(f'Error fetching item files from {server}: {r.status} {r.reason}', file = sys.stderr)
+		sys.exit(1)
+	root = xml.etree.ElementTree.fromstring(r.read().decode('utf-8'))
+	if root.tag != 'files' or not all(c.tag == 'file' for c in root):
+		print(f'Invalid XML received from {server}', file = sys.stderr)
+		sys.exit(1)
+	for file in root:
+		if file.attrib['name'] == filename:
+			for c in file:
+				if c.tag == 'sha1':
+					if c.text != sha1:
+						print(f'SHA-1 mismatch on {server}: expected {sha1}, found {c.text}', file = sys.stderr)
+						sys.exit(1)
+					break
+			else:
+				print(f'No SHA-1 found on {server}', file = sys.stderr)
+				sys.exit(1)
+			break
+	else:
+		print(f'File not found on {server}', file = sys.stderr)
+		sys.exit(1)