Ensure url prefixes have non-zero length

Author: hackermd

src/dicomweb_client/web.py

@@ -251,9 +251,25 @@ def __init__(
             session = requests.session()
         self._session = session
         self.base_url = url
+        if qido_url_prefix == '':
+            raise ValueError(
+                'Argument "qido_url_prefix" must not be a zero length string.'
+            )
         self.qido_url_prefix = qido_url_prefix
+        if wado_url_prefix == '':
+            raise ValueError(
+                'Argument "wado_url_prefix" must not be a zero length string.'
+            )
         self.wado_url_prefix = wado_url_prefix
+        if stow_url_prefix == '':
+            raise ValueError(
+                'Argument "stow_url_prefix" must not be a zero length string.'
+            )
         self.stow_url_prefix = stow_url_prefix
+        if delete_url_prefix == '':
+            raise ValueError(
+                'Argument "delete_url_prefix" must not be a zero length string.'
+            )
         self.delete_url_prefix = delete_url_prefix
 
         # This regular expression extracts the scheme and host name from the URL

tests/test_web.py

@@ -65,6 +65,13 @@ def test_url_prefixes(httpserver):
     assert client.stow_url_prefix == stow_url_prefix
 
 
+def test_url_prefixes_zero_length(httpserver):
+    for name in ('wado', 'qido', 'stow'):
+        kwargs = {f'{name}_url_prefix': ''}
+        with pytest.raises(ValueError):
+            DICOMwebClient(httpserver.url, **kwargs)
+
+
 def test_proxies(httpserver):
     protocol = 'http'
     address = 'foo.com'