client: fix relative paths

httplib/parser.py

@@ -1,4 +1,5 @@
 import logging
+import os.path
 import re
 from urllib.parse import urlparse, urlsplit
 
@@ -182,7 +183,6 @@ def parse_headers(lines):
     headers = []
     # first header after the status-line may not contain a space
     for line in lines:
-        line = next(lines)
         if line[0].isspace():
             continue
         else:
@@ -251,3 +251,9 @@ def base_url(uri: str):
     parsed = urlsplit(uri)
     path = parsed.path.rsplit("/", 1)[0]
     return f"{parsed.scheme}://{parsed.hostname}{path}/"
+
+
+def absolute_url(uri: str, rel_path: str):
+    parsed = urlsplit(uri)
+    path = os.path.normpath(os.path.join(parsed.path, rel_path))
+    return f"{parsed.scheme}://{parsed.hostname}{path}"