Merge ~adam-collard/maas:security-test-cleanup into maas:master

[Adam Collard]

Clean up test_security

Better test isolation, avoid flakiness by manipulating less global state

[MAAS Lander (maas-lander)]

UNIT TESTS
-b security-test-cleanup lp:~adam-collard/maas/+git/maas into -b master lp:~maas-committers/maas

STATUS: FAILED
LOG: http://maas-ci.internal:8080/job/maas/job/branch-tester/10824/console
COMMIT: d5d482dbad2fe5202d07db3b4bcc569f33883fc9

review: Needs Fixing

[Alberto Donato (ack)]

+1

needs lint fix though

review: Approve

[MAAS Lander (maas-lander)]

UNIT TESTS
-b security-test-cleanup lp:~adam-collard/maas/+git/maas into -b master lp:~maas-committers/maas

STATUS: FAILED
LOG: http://maas-ci.internal:8080/job/maas/job/branch-tester/10826/console
COMMIT: 09b5b2595ce3fd1ab14a6e0e08f8eb8c7ccb1aeb

review: Needs Fixing

[MAAS Lander (maas-lander)]

UNIT TESTS
-b security-test-cleanup lp:~adam-collard/maas/+git/maas into -b master lp:~maas-committers/maas

STATUS: SUCCESS
COMMIT: acfd78d5c90bb6b98be3e71922c662b0a597252c

review: Approve

diff --git a/src/provisioningserver/tests/test_security.py b/src/provisioningserver/tests/test_security.py
index 7acdc70..b008ea5 100644
--- a/src/provisioningserver/tests/test_security.py
+++ b/src/provisioningserver/tests/test_security.py
@@ -19,7 +19,6 @@ from maastesting.factory import factory
 from maastesting.matchers import MockCalledOnceWith
 from maastesting.testcase import MAASTestCase
 from provisioningserver import security
-from provisioningserver.path import get_maas_data_path
 from provisioningserver.security import (
     fernet_decrypt_psk,
     fernet_encrypt_psk,
@@ -33,11 +32,9 @@ class SharedSecretTestCase(MAASTestCase):
         get_secret = self.patch(security, "get_shared_secret_filesystem_path")
         # Ensure each test uses a different filename for the shared secret,
         # so that tests cannot interfere with each other.
-        get_secret.return_value = Path(
-            get_maas_data_path("secret-%s" % factory.make_string(16))
-        )
-        # Extremely unlikely, but just in case.
-        self.delete_secret()
+        secret_dir = Path(self.make_dir())
+        get_secret.return_value = secret_dir / "secret"
+        self.patch(security, "_fernet_psk", value=None)
         self.addCleanup(
             setattr,
             security,
@@ -48,16 +45,6 @@ class SharedSecretTestCase(MAASTestCase):
         security.DEFAULT_ITERATION_COUNT = 2
         super().setUp()
 
-    def tearDown(self):
-        self.delete_secret()
-        super().tearDown()
-
-    def delete_secret(self):
-        security._fernet_psk = None
-        secret_file = security.get_shared_secret_filesystem_path()
-        if secret_file.exists():
-            secret_file.unlink()
-
     def write_secret(self):
         secret = factory.make_bytes()
         secret_path = security.get_shared_secret_filesystem_path()