Files
mongo/jstests/multiVersion/genericSetFCVUsage/downgrade_replset.js
Zac 591928c619 SERVER-108478 JS formatted by prettier and remove clang-format (#39656)
GitOrigin-RevId: 6c8f6aded47f260aa4f7c231b17dae3302cb1e04
2025-08-21 17:27:09 +00:00

76 lines
2.9 KiB
JavaScript

import "jstests/multiVersion/libs/multi_rs.js";
import {ReplSetTest} from "jstests/libs/replsettest.js";
import {isFinished, startParallelOps} from "jstests/libs/test_background_ops.js";
import {reconnect} from "jstests/replsets/rslib.js";
let newVersion = "latest";
let name = "replsetdowngrade";
let nodes = {
n1: {binVersion: newVersion},
n2: {binVersion: newVersion},
n3: {binVersion: newVersion},
};
function runDowngradeTest(downgradeVersion) {
jsTestLog("Running test with 'downgradeVersion': " + downgradeVersion);
const downgradeFCV = binVersionToFCV(downgradeVersion);
let rst = new ReplSetTest({name: name, nodes: nodes, waitForKeys: true});
rst.startSet();
rst.initiate(null, null, {initiateWithDefaultElectionTimeout: true});
let primary = rst.getPrimary();
let coll = "test.foo";
// The default FCV is latestFCV for non-shard replica sets.
let primaryAdminDB = rst.getPrimary().getDB("admin");
checkFCV(primaryAdminDB, latestFCV);
// We wait for the feature compatibility version to be set to the downgraded FCV on all nodes of
// the replica set in order to ensure that all nodes can be successfully downgraded. This
// effectively allows us to emulate upgrading to the latest version with existing data files and
// then trying to downgrade the FCV.
assert.commandWorked(primary.adminCommand({setFeatureCompatibilityVersion: downgradeFCV, confirm: true}));
rst.awaitReplication();
jsTest.log("Inserting documents into collection.");
for (let i = 0; i < 10; i++) {
primary.getCollection(coll).insert({_id: i, str: "hello world"});
}
function insertDocuments(rsURL, collParam) {
let coll = new Mongo(rsURL).getCollection(collParam);
let count = 10;
while (!isFinished()) {
assert.commandWorked(coll.insert({_id: count, str: "hello world"}));
count++;
}
}
jsTest.log("Starting parallel operations during downgrade..");
let joinFindInsert = startParallelOps(primary, insertDocuments, [rst.getURL(), coll]);
jsTest.log("Downgrading replica set..");
rst.upgradeSet({binVersion: downgradeVersion});
jsTest.log("Downgrade complete.");
// We save a reference to the old primary so that we can call reconnect() on it before
// joinFindInsert() would attempt to send the node an update operation that signals the parallel
// shell running the background operations to stop.
let oldPrimary = primary;
primary = rst.getPrimary();
printjson(rst.status());
// Since the old primary was restarted as part of the downgrade process, we explicitly reconnect
// to it so that sending it an update operation silently fails with an unchecked
// NotWritablePrimary error rather than a network error.
reconnect(oldPrimary.getDB("admin"));
joinFindInsert();
rst.stopSet();
}
runDowngradeTest("last-continuous");
runDowngradeTest("last-lts");