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/**
* Test that we can successfully reconstruct a prepared transaction that was prepared before the
* stable timestamp at the end of startup recovery.
*
* @tags: [requires_persistence, uses_transactions, uses_prepare_transaction]
*/
(function() {
"use strict";
load("jstests/core/txns/libs/prepare_helpers.js");
load("jstests/aggregation/extras/utils.js");
const replTest = new ReplSetTest({nodes: 1});
replTest.startSet();
replTest.initiate();
let primary = replTest.getPrimary();
const dbName = "test";
const collName = "startup_recovery_reconstructs_txn_prepared_before_stable";
const testDB = primary.getDB(dbName);
let testColl = testDB.getCollection(collName);
assert.commandWorked(testColl.insert({_id: 0}));
// Start a session on the primary.
let session = primary.startSession();
const sessionID = session.getSessionId();
let sessionDB = session.getDatabase(dbName);
let sessionColl = sessionDB.getCollection(collName);
// Prepare the transaction on the session.
session.startTransaction();
// We are creating a record size of 14MB for _id '0', just to make sure when this
// test runs with lesser wiredTiger cache size, there would be a higher possibility
// of this record being considered for eviction from in-memory tree. And, to confirm
// that we don't see problems like in SERVER-40422.
const largeArray = new Array(14 * 1024 * 1024).join('x');
assert.commandWorked(sessionColl.update({_id: 0}, {$set: {a: largeArray}}));
assert.commandWorked(sessionColl.insert({_id: 1}));
const prepareTimestamp = PrepareHelpers.prepareTransaction(session);
// Fastcount reflects the insert of a prepared transaction.
assert.eq(testColl.count(), 2);
jsTestLog("Do a majority write to advance the stable timestamp past the prepareTimestamp");
// Doing a majority write after preparing the transaction ensures that the stable timestamp is
// past the prepare timestamp because this write must be in the committed snapshot.
assert.commandWorked(
testColl.runCommand("insert", {documents: [{_id: 2}]}, {writeConcern: {w: "majority"}}));
// Fastcount reflects the insert of a prepared transaction.
assert.eq(testColl.count(), 3);
// Check that we have one transaction in the transactions table.
assert.eq(primary.getDB('config')['transactions'].find().itcount(), 1);
jsTestLog("Restarting node");
// Perform a clean shutdown and restart. And, the data restored at the storage recovery
// timestamp should not reflect the prepared transaction.
replTest.stop(primary, undefined, {skipValidation: true});
// Since the oldest timestamp is same as the stable timestamp during node's restart, this test
// will reconstruct a prepared transaction older than oldest timestamp during startup recovery.
replTest.start(primary, {}, true);
jsTestLog("Node was restarted");
primary = replTest.getPrimary();
testColl = primary.getDB(dbName)[collName];
// Make sure we cannot see the writes from the prepared transaction yet.
arrayEq(testColl.find().toArray(), [{_id: 0}, {_id: 2}]);
assert.eq(testColl.count(), 3);
// Make sure there is still one transaction in the transactions table. This is because the
// entry in the transactions table is made durable when a transaction is prepared.
assert.eq(primary.getDB('config')['transactions'].find().itcount(), 1);
// Make sure we can successfully commit the recovered prepared transaction.
session = PrepareHelpers.createSessionWithGivenId(primary, sessionID);
sessionDB = session.getDatabase(dbName);
// The transaction on this session should have a txnNumber of 0. We explicitly set this
// since createSessionWithGivenId does not restore the current txnNumber in the shell.
session.setTxnNumber_forTesting(0);
const txnNumber = session.getTxnNumber_forTesting();
// Make sure we cannot add any operations to a prepared transaction.
assert.commandFailedWithCode(sessionDB.runCommand({
insert: collName,
txnNumber: NumberLong(txnNumber),
documents: [{_id: 10}],
autocommit: false,
}),
ErrorCodes.PreparedTransactionInProgress);
// Make sure that writing to a document that was updated in the prepared transaction causes
// a write conflict.
assert.commandFailedWithCode(
sessionDB.runCommand(
{update: collName, updates: [{q: {_id: 0}, u: {$set: {a: 2}}}], maxTimeMS: 5 * 1000}),
ErrorCodes.MaxTimeMSExpired);
jsTestLog("Committing the prepared transaction");
assert.commandWorked(sessionDB.adminCommand({
commitTransaction: 1,
commitTimestamp: prepareTimestamp,
txnNumber: NumberLong(txnNumber),
autocommit: false,
}));
// Make sure we can see the effects of the prepared transaction.
arrayEq(testColl.find().toArray(), [{_id: 0, a: largeArray}, {_id: 1}, {_id: 2}]);
assert.eq(testColl.count(), 3);
replTest.stopSet();
}());
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