[DPE-2609] Remove support of Juju 2.9 (#257)

The goal of this PR is to remove Juju 2.9 specific code related to
secrets since we are dropping support of Juju 2.9

lib/charms/mongodb/v0/mongodb_backups.py

@@ -523,7 +523,7 @@ def _try_to_restore(self, backup_id: str) -> None:
                         restore_cmd = restore_cmd + remapping_args.split(" ")
                     self.charm.run_pbm_command(restore_cmd)
                 except (subprocess.CalledProcessError, ExecError) as e:
-                    if type(e) == subprocess.CalledProcessError:
+                    if type(e) is subprocess.CalledProcessError:
                         error_message = e.output.decode("utf-8")
                     else:
                         error_message = str(e.stderr)
@@ -560,7 +560,7 @@ def _try_to_backup(self):
                     )
                     return backup_id_match.group("backup_id") if backup_id_match else "N/A"
                 except (subprocess.CalledProcessError, ExecError) as e:
-                    if type(e) == subprocess.CalledProcessError:
+                    if type(e) is subprocess.CalledProcessError:
                         error_message = e.output.decode("utf-8")
                     else:
                         error_message = str(e.stderr)
@@ -636,13 +636,13 @@ def _get_backup_restore_operation_result(self, current_pbm_status, previous_pbm_
         to contain the operation type (backup/restore) and the backup id.
         """
         if (
-            type(current_pbm_status) == type(previous_pbm_status)
+            type(current_pbm_status) is type(previous_pbm_status)
             and current_pbm_status.message == previous_pbm_status.message
         ):
             return f"Operation is still in progress: '{current_pbm_status.message}'"
 
         if (
-            type(previous_pbm_status) == MaintenanceStatus
+            type(previous_pbm_status) is MaintenanceStatus
             and "backup id:" in previous_pbm_status.message
         ):
             backup_id = previous_pbm_status.message.split("backup id:")[-1].strip()
@@ -679,7 +679,7 @@ def retrieve_error_message(self, pbm_status: Dict) -> str:
 
     def process_pbm_error(self, pbm_status: Optional[_StrOrBytes]) -> str:
         """Returns errors found in PBM status."""
-        if type(pbm_status) == bytes:
+        if type(pbm_status) is bytes:
             pbm_status = pbm_status.decode("utf-8")
 
         try:

src/charm.py

@@ -40,7 +40,6 @@
     OperatorUser,
 )
 from charms.operator_libs_linux.v1 import snap
-from ops import JujuVersion
 from ops.charm import (
     ActionEvent,
     CharmBase,
@@ -252,10 +251,6 @@ def db_initialised(self, value):
                 f"'db_initialised' must be a boolean value. Proivded: {value} is of type {type(value)}"
             )
 
-    @property
-    def _juju_has_secrets(self) -> bool:
-        return JujuVersion.from_environ().has_secrets
-
     # END: properties
 
     # BEGIN: charm event handlers
@@ -1006,39 +1001,17 @@ def _unit_ip(self, unit: Unit) -> str:
 
     def get_secret(self, scope: str, key: str) -> Optional[str]:
         """Get secret from the secret storage."""
-        if self._juju_has_secrets:
-            return self._juju_secret_get(scope, key)
-
-        if scope == UNIT_SCOPE:
-            return self.unit_peer_data.get(key, None)
-        elif scope == APP_SCOPE:
-            return self.app_peer_data.get(key, None)
-        else:
-            raise RuntimeError("Unknown secret scope.")
+        return self._juju_secret_get(scope, key)
 
     def set_secret(self, scope: str, key: str, value: Optional[str]) -> Optional[str]:
         """Set secret in the secret storage.
 
         Juju versions > 3.0 use `juju secrets`, this function first checks
           which secret store is being used before setting the secret.
         """
-        if self._juju_has_secrets:
-            if not value:
-                return self._juju_secret_remove(scope, key)
-            return self._juju_secret_set(scope, key, value)
-
-        if scope == UNIT_SCOPE:
-            if not value:
-                del self.unit_peer_data[key]
-                return
-            self.unit_peer_data.update({key: str(value)})
-        elif scope == APP_SCOPE:
-            if not value:
-                del self.app_peer_data[key]
-                return
-            self.app_peer_data.update({key: str(value)})
-        else:
-            raise RuntimeError("Unknown secret scope.")
+        if not value:
+            return self._juju_secret_remove(scope, key)
+        return self._juju_secret_set(scope, key, value)
 
     def start_mongod_service(self):
         """Starts the mongod service and if necessary starts mongos.

tests/integration/test_charm.py

@@ -206,7 +206,6 @@ async def test_only_leader_can_set_while_all_can_read_password_secret(ops_test:
         assert password2 == password
 
 
-@pytest.mark.usefixtures("only_with_juju_secrets")
 async def test_reset_and_get_password_secret_same_as_cli(ops_test: OpsTest) -> None:
     """Test verifies that we can set and retrieve the correct password using Juju 3.x secrets."""
     new_password = str(uuid4())
@@ -231,21 +230,6 @@ async def test_reset_and_get_password_secret_same_as_cli(ops_test: OpsTest) -> N
     assert data[secret_id]["content"]["Data"]["monitor-password"] == password
 
 
-@pytest.mark.usefixtures("only_without_juju_secrets")
-async def test_reset_and_get_password_no_secret(ops_test: OpsTest, mocker) -> None:
-    """Test verifies that we can set and retrieve the correct password using Juju 2.x."""
-    new_password = str(uuid4())
-
-    # Re=setting existing password
-    leader_id = await get_leader_id(ops_test)
-    await set_password(ops_test, unit_id=leader_id, username="monitor", password=new_password)
-
-    # Getting back the pw programmatically
-    password = await get_password(ops_test, username="monitor")
-    assert password == new_password
-
-
-@pytest.mark.usefixtures("only_with_juju_secrets")
 async def test_empty_password(ops_test: OpsTest) -> None:
     """Test that the password can't be set to an empty string."""
     leader_id = await get_leader_id(ops_test)
@@ -258,7 +242,6 @@ async def test_empty_password(ops_test: OpsTest) -> None:
     assert password1 == password2
 
 
-@pytest.mark.usefixtures("only_with_juju_secrets")
 async def test_no_password_change_on_invalid_password(ops_test: OpsTest) -> None:
     """Test that in general, there is no change when password validation fails."""
     leader_id = await get_leader_id(ops_test)