Tests: Unlock running the test suite without OPS credentials

While it will only cover parts of the test suite, which is unfortunate,
at least it will not break. This is relevant for CI/GHA, because pull
requests submitted by external contributors do not have access to the
OPS credentials per GitHub Actions Secrets. C'est la vie.

tests/conftest.py

@@ -1,7 +1,7 @@
 import pytest
 
 from .helpers import mkcache, mksqlite, mkthrottler
-from .secrets import OPS_KEY, OPS_SECRET
+from .secrets import get_secrets_or_skip_tests
 
 
 @pytest.fixture
@@ -12,9 +12,9 @@ def storage(request):
 @pytest.fixture
 def reset_cached_client(request):
     from epo_ops import Client
-
+    ops_key, ops_secret = get_secrets_or_skip_tests()
     return Client(
-        OPS_KEY, OPS_SECRET, middlewares=[mkcache(request), mkthrottler(request)]
+        ops_key, ops_secret, middlewares=[mkcache(request), mkthrottler(request)]
     )
 
 
@@ -31,15 +31,17 @@ def module_cache(request):
 @pytest.fixture(scope="module")
 def default_client(request):
     from epo_ops import Client
+    ops_key, ops_secret = get_secrets_or_skip_tests()
 
-    return Client(OPS_KEY, OPS_SECRET, middlewares=[mkthrottler(request)])
+    return Client(ops_key, ops_secret, middlewares=[mkthrottler(request)])
 
 
 @pytest.fixture(scope="module")
 def cached_client(request, module_cache):
     from epo_ops import Client
+    ops_key, ops_secret = get_secrets_or_skip_tests()
 
-    return Client(OPS_KEY, OPS_SECRET, middlewares=[module_cache, mkthrottler(request)])
+    return Client(ops_key, ops_secret, middlewares=[module_cache, mkthrottler(request)])
 
 
 @pytest.fixture(scope="module", params=["cached_client", "default_client"])

tests/secrets.py

@@ -9,6 +9,7 @@
 import os
 from os.path import abspath, dirname, join
 
+import pytest
 from dotenv import load_dotenv
 
 # Prune environment variables.
@@ -20,6 +21,13 @@
 dotenv_path = abspath(join(dirname(__file__), "../.env"))
 load_dotenv(dotenv_path)
 
+
 # Set environment variables as constants.
-OPS_KEY = os.environ["OPS_KEY"]
-OPS_SECRET = os.environ["OPS_SECRET"]
+def get_secrets_or_skip_tests():
+    try:
+        ops_key = os.environ["OPS_KEY"]
+        ops_secret = os.environ["OPS_SECRET"]
+    except KeyError as ex:
+        raise pytest.skip("No OPS credentials configured") from ex
+
+    return ops_key, ops_secret