diff --git a/stw_potsdam/swp_webspeiseplan_api.py b/stw_potsdam/swp_webspeiseplan_api.py
index b485237..bdef6dc 100644
--- a/stw_potsdam/swp_webspeiseplan_api.py
+++ b/stw_potsdam/swp_webspeiseplan_api.py
@@ -1,9 +1,22 @@
 import logging
 import urllib.request
+import urllib.parse
 import re
 import time
 import json
 
+from dataclasses import dataclass
+
+
+@dataclass(frozen=True)
+class SWPWebspeiseplanData:
+    """Downloaded SWP Webspeiseplan data grouped by outlet name."""
+
+    outlets: dict[str, dict]
+    locations: dict[str, dict]
+    menus: dict[str, dict]
+    meal_categories: dict[str, dict]
+
 
 class SWPWebspeiseplanAPI:
     """This class is used download content from SWP_Webspeiseplan.
@@ -16,25 +29,34 @@ class SWPWebspeiseplanAPI:
     logger = logging.getLogger(__name__)
 
     def __init__(self):
-        """Initialize the configuration for the web service."""
+        """Initialize the web service client."""
         logging.basicConfig()
+
+    def fetch_all(self) -> SWPWebspeiseplanData:
+        """Download all data required to render OpenMensa feeds."""
         proxy_token = self.parse_token()
-        self.outlets = self.parse_outlets(proxy_token)
-        self.locations: dict[str, dict] = {}
+        outlets = self.parse_outlets(proxy_token)
         locations = {
             item["id"]: item
             for item in self.parse_location(proxy_token)
         }
-        self.menus: dict[str, dict] = {}
-        self.meal_categories: dict[str, dict] = {}
-        for outlet in self.outlets.values():
+        menus: dict[str, dict] = {}
+        meal_categories: dict[str, dict] = {}
+        outlet_locations: dict[str, dict] = {}
+        for outlet in outlets.values():
             location = outlet["standortID"]
             menu = self.parse_menu(proxy_token, location)
             categories = self.parse_meal_category(proxy_token, location)
             id2cat = {item["gerichtkategorieID"]: item for item in categories}
-            self.menus[outlet["name"]] = menu
-            self.meal_categories[outlet["name"]] = id2cat
-            self.locations[outlet["name"]] = locations[location]
+            menus[outlet["name"]] = menu
+            meal_categories[outlet["name"]] = id2cat
+            outlet_locations[outlet["name"]] = locations[location]
+        return SWPWebspeiseplanData(
+            outlets=outlets,
+            locations=outlet_locations,
+            menus=menus,
+            meal_categories=meal_categories,
+        )
 
     def __spoof_req_headers(self, req: urllib.request.Request):
         """Add headers to a request .
@@ -77,9 +99,8 @@ class SWPWebspeiseplanAPI:
         Returns:
             [type]: [description]
         """
-        url = f"{SWPWebspeiseplanAPI.URL_BASE}/index.php?" + "&".join(
-            [f"{k}={v}" for k, v in params.items()]
-        )
+        query = urllib.parse.urlencode(params)
+        url = f"{SWPWebspeiseplanAPI.URL_BASE}/index.php?{query}"
         SWPWebspeiseplanAPI.logger.debug("__parse_model: %s", url)
         req = urllib.request.Request(url)
         self.__spoof_req_headers(req)
diff --git a/stw_potsdam/xml_types/builder.py b/stw_potsdam/xml_types/builder.py
index a2ecaa7..91cd3b2 100644
--- a/stw_potsdam/xml_types/builder.py
+++ b/stw_potsdam/xml_types/builder.py
@@ -3,7 +3,10 @@ from dataclasses import dataclass
 import logging
 from flask import url_for
 from stw_potsdam.xml_types.openmensa_xml import OpenMensaXML
-from stw_potsdam.swp_webspeiseplan_api import SWPWebspeiseplanAPI
+from stw_potsdam.swp_webspeiseplan_api import (
+    SWPWebspeiseplanAPI,
+    SWPWebspeiseplanData,
+)
 from stw_potsdam.swp_webspeiseplan_parser import SWPWebspeiseplanParser
 from stw_potsdam.config import Canteen
 from stw_potsdam.xml_types.feed_xml import FeedXML, ScheduleXML
@@ -15,21 +18,26 @@ class Builder:
 
     VERSION = "2.0.1"
 
-    def __init__(self, config: dict[str, Canteen]):
+    def __init__(
+        self,
+        config: dict[str, Canteen],
+        swp_data: SWPWebspeiseplanData | None = None,
+    ):
         """Initialize the object for the OpenMensa Feed Doc XML."""
         logging.basicConfig()
         self.logger = logging.getLogger(__name__)
         self._xml_data = {}
-        swp_api = SWPWebspeiseplanAPI()
+        if swp_data is None:
+            swp_data = SWPWebspeiseplanAPI().fetch_all()
         swp_parser = SWPWebspeiseplanParser()
         for cname, ntup in config.items():
-            if ntup.name not in swp_api.outlets.keys():
+            if ntup.name not in swp_data.outlets.keys():
                 self.logger.warning("%s not found in keys", ntup.name)
                 continue
-            outlet = swp_api.outlets[ntup.name]
-            menus = swp_api.menus[ntup.name]
-            categories = swp_api.meal_categories[ntup.name]
-            locations = swp_api.locations[ntup.name]
+            outlet = swp_data.outlets[ntup.name]
+            menus = swp_data.menus[ntup.name]
+            categories = swp_data.meal_categories[ntup.name]
+            locations = swp_data.locations[ntup.name]
             outlet["isPublic"] = locations["isPublic"]
             canteen = swp_parser.parse_canteen_meta_times(outlet)
             meals = swp_parser.parse_meals(menus, categories)
diff --git a/tests/test_swp_webspeiseplan_api.py b/tests/test_swp_webspeiseplan_api.py
new file mode 100644
index 0000000..4848b37
--- /dev/null
+++ b/tests/test_swp_webspeiseplan_api.py
@@ -0,0 +1,12 @@
+# -*- encoding: utf-8 -*-
+
+from stw_potsdam.swp_webspeiseplan_api import SWPWebspeiseplanAPI
+
+# pytest fixtures are linked via parameter names of test methods
+# pragma pylint: disable=unused-import,unused-argument,redefined-outer-name
+from tests.stub_api import api_offline
+
+
+def test_api_init_does_not_fetch(api_offline):
+    """Creating the API client does not perform network requests."""
+    SWPWebspeiseplanAPI()