SERVER-53953 Use safe reconfigs for setFCV command

2 files changed, 60 insertions, 12 deletions

diff --git a/jstests/multiVersion/genericSetFCVUsage/upgrade_downgrade_idempotency.js b/jstests/multiVersion/genericSetFCVUsage/upgrade_downgrade_idempotency.js
new file mode 100644
index 00000000000..ff24256908a
--- /dev/null
+++ b/jstests/multiVersion/genericSetFCVUsage/upgrade_downgrade_idempotency.js
@@ -0,0 +1,60 @@
+/**
+ * Tests the idempotency of the 'setFeatureCompatibilityVersion' command.
+ * We execute the following steps for both upgrade and downgrade:
+ * 1. Enable a failpoint to fail upgrading/downgrading.
+ * 2. Issue a setFeatureCompatibilityVersion command, which upgrades/downgrades
+ *    the replica set to a kUpgrading/kDowngrading intermediary state.
+ * 3. The setFeatureCompatibilityVersion command fails without completing all
+ *    upgrade/downgrade behavior.
+ * 4. Disable the failpoint, and issue a succesful setFeatureCompatibilityVersion
+ *    to finish upgrading/downgrading.
+ */
+
+(function() {
+"use strict";
+
+load("jstests/libs/write_concern_util.js");
+
+function runTest(downgradeVersion) {
+    const downgradeFCV = binVersionToFCV(downgradeVersion);
+    const replTest = new ReplSetTest({name: jsTestName(), nodes: 2});
+    replTest.startSet();
+    replTest.initiate();
+
+    let primary = replTest.getPrimary();
+    // Enable failpoint to fail downgrading.
+    let failpoint = configureFailPoint(primary, 'failDowngrading');
+    assert.commandFailed(primary.adminCommand({setFeatureCompatibilityVersion: downgradeFCV}));
+
+    // Verify the node is in an intermediary state. If the response object has the 'targetVersion'
+    // field, we are in a partially upgraded or downgraded state.
+    checkFCV(primary.getDB("admin"), downgradeFCV, downgradeFCV);
+
+    failpoint.off();
+
+    assert.commandWorked(primary.adminCommand({setFeatureCompatibilityVersion: downgradeFCV}));
+
+    // Verify the feature compatibility version transition is complete.
+    checkFCV(primary.getDB("admin"), downgradeFCV);
+
+    const latestFCV = binVersionToFCV('latest');
+    // Enable failpoint to fail upgrading.
+    failpoint = configureFailPoint(primary, 'failUpgrading');
+    assert.commandFailed(primary.adminCommand({setFeatureCompatibilityVersion: latestFCV}));
+
+    // Verify the node is in an intermediary state. If the response object has the 'targetVersion'
+    // field, we are in a partially upgraded or downgraded state.
+    checkFCV(primary.getDB("admin"), downgradeFCV, latestFCV);
+
+    failpoint.off();
+    assert.commandWorked(primary.adminCommand({setFeatureCompatibilityVersion: latestFCV}));
+
+    // Verify the feature compatibility version transition is complete.
+    checkFCV(primary.getDB("admin"), latestFCV);
+
+    replTest.stopSet();
+}
+
+runTest('last-lts');
+runTest('last-continuous');
+}());
\ No newline at end of file
diff --git a/jstests/noPassthrough/index_downgrade_fcv.js b/jstests/noPassthrough/index_downgrade_fcv.js
index be0e879af8d..771471d74a0 100644
--- a/jstests/noPassthrough/index_downgrade_fcv.js
+++ b/jstests/noPassthrough/index_downgrade_fcv.js
@@ -30,18 +30,6 @@ const primary = rst.getPrimary();
 const testDB = primary.getDB('test');
 const coll = testDB.getCollection('test');
 
-// TODO SERVER-53953: Remove to re-enable test for feature flag enabled variants.
-const res = assert.commandWorked(
-    primary.adminCommand({getParameter: 1, featureFlagUseSecondaryDelaySecs: 1}),
-    "Failed to call getParameter on feature flag: featureFlagUseSecondaryDelaySecs");
-const featureFlagUseSecondaryDelaySecsEnabled = res.featureFlagUseSecondaryDelaySecs.value;
-
-if (featureFlagUseSecondaryDelaySecsEnabled) {
-    jsTestLog("Skipping test because the useSecondaryDelaySecs feature flag is enabled");
-    rst.stopSet();
-    return;
-}
-
 assert.commandWorked(coll.insert({a: 1}));
 
 IndexBuildTest.pauseIndexBuilds(primary);