diff --git a/swh/lister/core/lister_transports.py b/swh/lister/core/lister_transports.py
index 020eece..4e116f9 100644
--- a/swh/lister/core/lister_transports.py
+++ b/swh/lister/core/lister_transports.py
@@ -41,6 +41,30 @@ class SWHListerHttpTransport(abc.ABC):
             'User-Agent': 'Software Heritage lister (%s)' % self.lister_version
         }
 
+    def request_uri(self, identifier):
+        """Get the full request URI given the transport_request identifier.
+
+        MAY BE OVERRIDDEN if something more complex than the PATH_TEMPLATE is
+        required.
+        """
+        path = self.PATH_TEMPLATE % identifier
+        return self.api_baseurl + path
+
+    def request_params(self, identifier):
+        """Get the full parameters passed to requests given the transport_request
+        identifier.
+
+        MAY BE OVERRIDDEN if something more complex than the request headers
+        ois needed.
+        """
+        params = {}
+        params['headers'] = self.request_headers() or {}
+        creds = self.config['credentials']
+        auth = random.choice(creds) if creds else None
+        if auth:
+            params['auth'] = (auth['username'], auth['password'])
+        return params
+
     def transport_quota_check(self, response):
         """Implements SWHListerBase.transport_quota_check with standard 429 code
             check for HTTP with Requests library.
@@ -73,15 +97,11 @@ class SWHListerHttpTransport(abc.ABC):
     def transport_request(self, identifier):
         """Implements SWHListerBase.transport_request for HTTP using Requests.
         """
-        path = self.PATH_TEMPLATE % identifier
-        params = {}
-        params['headers'] = self.request_headers() or {}
-        creds = self.config['credentials']
-        auth = random.choice(creds) if creds else None
-        if auth:
-            params['auth'] = (auth['username'], auth['password'])
+        path = self.request_uri(identifier)
+        params = self.request_params(identifier)
+
         try:
-            response = self.session.get(self.api_baseurl + path, **params)
+            response = self.session.get(path, **params)
         except requests.exceptions.ConnectionError as e:
             raise FetchError(e)
         else: