/** * Exercises the coordinator commands logic by simulating a basic two phase commit and basic two * phase abort. * * @tags: [uses_transactions, uses_prepare_transaction, uses_multi_shard_transaction] */ import {configureFailPoint} from "jstests/libs/fail_point_util.js"; import {ShardingTest} from "jstests/libs/shardingtest.js"; import { checkDecisionIs, checkDocumentDeleted, runCommitThroughMongosInParallelThread, } from "jstests/sharding/libs/txn_two_phase_commit_util.js"; const dbName = "test"; const collName = "foo"; const ns = dbName + "." + collName; let st = new ShardingTest({shards: 3, causallyConsistent: true}); let coordinator = st.shard0; let participant1 = st.shard1; let participant2 = st.shard2; let expectedParticipantList = [participant1.shardName, participant2.shardName, coordinator.shardName]; let lsid = {id: UUID()}; let txnNumber = 0; const checkParticipantListMatches = function (coordinatorConn, lsid, txnNumber, expectedParticipantList) { let coordDoc = coordinatorConn .getDB("config") .getCollection("transaction_coordinators") .findOne({"_id.lsid.id": lsid.id, "_id.txnNumber": txnNumber}); assert.neq(null, coordDoc); assert.sameMembers(coordDoc.participants, expectedParticipantList); }; const startSimulatingNetworkFailures = function (connArray) { connArray.forEach(function (conn) { assert.commandWorked( conn.adminCommand({ configureFailPoint: "failCommand", mode: {times: 10}, data: { errorCode: ErrorCodes.NotWritablePrimary, failCommands: ["prepareTransaction", "abortTransaction", "commitTransaction"], }, }), ); assert.commandWorked( conn.adminCommand({ configureFailPoint: "participantReturnNetworkErrorForPrepareAfterExecutingPrepareLogic", mode: {times: 5}, }), ); assert.commandWorked( conn.adminCommand({ configureFailPoint: "participantReturnNetworkErrorForAbortAfterExecutingAbortLogic", mode: {times: 5}, }), ); assert.commandWorked( conn.adminCommand({ configureFailPoint: "participantReturnNetworkErrorForCommitAfterExecutingCommitLogic", mode: {times: 5}, }), ); }); }; const stopSimulatingNetworkFailures = function (connArray) { connArray.forEach(function (conn) { assert.commandWorked( conn.adminCommand({ configureFailPoint: "failCommand", mode: "off", }), ); assert.commandWorked( conn.adminCommand({ configureFailPoint: "participantReturnNetworkErrorForPrepareAfterExecutingPrepareLogic", mode: "off", }), ); assert.commandWorked( conn.adminCommand({ configureFailPoint: "participantReturnNetworkErrorForAbortAfterExecutingAbortLogic", mode: "off", }), ); assert.commandWorked( conn.adminCommand({ configureFailPoint: "participantReturnNetworkErrorForCommitAfterExecutingCommitLogic", mode: "off", }), ); }); }; const setUp = function () { // Create a sharded collection with a chunk on each shard: // shard0: [-inf, 0) // shard1: [0, 10) // shard2: [10, +inf) assert.commandWorked(st.s.adminCommand({enableSharding: dbName, primaryShard: coordinator.shardName})); assert.commandWorked(st.s.adminCommand({shardCollection: ns, key: {_id: 1}})); assert.commandWorked(st.s.adminCommand({split: ns, middle: {_id: 0}})); assert.commandWorked(st.s.adminCommand({split: ns, middle: {_id: 10}})); assert.commandWorked(st.s.adminCommand({moveChunk: ns, find: {_id: 0}, to: participant1.shardName})); assert.commandWorked(st.s.adminCommand({moveChunk: ns, find: {_id: 10}, to: participant2.shardName})); // These forced refreshes are not strictly necessary; they just prevent extra TXN log lines // from the shards starting, aborting, and restarting the transaction due to needing to // refresh after the transaction has started. assert.commandWorked(coordinator.adminCommand({_flushRoutingTableCacheUpdates: ns})); assert.commandWorked(participant1.adminCommand({_flushRoutingTableCacheUpdates: ns})); assert.commandWorked(participant2.adminCommand({_flushRoutingTableCacheUpdates: ns})); st.refreshCatalogCacheForNs(st.s, ns); // Start a new transaction by inserting a document onto each shard. assert.commandWorked( st.s.getDB(dbName).runCommand({ insert: collName, documents: [{_id: -5}, {_id: 5}, {_id: 15}], lsid: lsid, txnNumber: NumberLong(txnNumber), stmtId: NumberInt(0), startTransaction: true, autocommit: false, }), ); }; const testCommitProtocol = function (shouldCommit, simulateNetworkFailures) { jsTest.log( "Testing two-phase " + (shouldCommit ? "commit" : "abort") + " protocol with simulateNetworkFailures: " + simulateNetworkFailures, ); txnNumber++; setUp(); if (!shouldCommit) { // Manually abort the transaction on one of the participants, so that the participant // fails to prepare. assert.commandWorked( participant2.adminCommand({ abortTransaction: 1, lsid: lsid, txnNumber: NumberLong(txnNumber), stmtId: NumberInt(0), autocommit: false, }), ); } if (simulateNetworkFailures) { startSimulatingNetworkFailures([participant1, participant2]); } // Turn on failpoints so that the coordinator hangs after each write it does, so that the // test can check that the write happened correctly. const hangBeforeWaitingForParticipantListWriteConcernFp = configureFailPoint( coordinator, "hangBeforeWaitingForParticipantListWriteConcern", {}, "alwaysOn", ); const hangBeforeWaitingForDecisionWriteConcernFp = configureFailPoint( coordinator, "hangBeforeWaitingForDecisionWriteConcern", {}, "alwaysOn", ); // Run commitTransaction through a parallel shell. let commitThread; if (shouldCommit) { commitThread = runCommitThroughMongosInParallelThread(lsid, txnNumber, st.s.host); } else { commitThread = runCommitThroughMongosInParallelThread(lsid, txnNumber, st.s.host, ErrorCodes.NoSuchTransaction); } commitThread.start(); // Check that the coordinator wrote the participant list. hangBeforeWaitingForParticipantListWriteConcernFp.wait(); checkParticipantListMatches(coordinator, lsid, txnNumber, expectedParticipantList); hangBeforeWaitingForParticipantListWriteConcernFp.off(); // Check that the coordinator wrote the decision. hangBeforeWaitingForDecisionWriteConcernFp.wait(); checkParticipantListMatches(coordinator, lsid, txnNumber, expectedParticipantList); const commitTimestamp = checkDecisionIs(coordinator, lsid, txnNumber, shouldCommit ? "commit" : "abort"); hangBeforeWaitingForDecisionWriteConcernFp.off(); // Check that the coordinator deleted its persisted state. commitThread.join(); assert.soon(function () { return checkDocumentDeleted(coordinator, lsid, txnNumber); }); if (simulateNetworkFailures) { stopSimulatingNetworkFailures([participant1, participant2]); } // Check that the transaction committed or aborted as expected. if (!shouldCommit) { jsTest.log("Verify that the transaction was aborted on all shards."); assert.eq(0, st.s.getDB(dbName).getCollection(collName).find().itcount()); } else { jsTest.log("Verify that the transaction was committed on all shards."); const res = assert.commandWorked( st.s.getDB(dbName).runCommand({ find: collName, readConcern: {level: "majority", afterClusterTime: commitTimestamp}, maxTimeMS: 10000, }), ); assert.eq(3, res.cursor.firstBatch.length); } st.s.getDB(dbName).getCollection(collName).drop(); }; testCommitProtocol(false /* test abort */, false /* no network failures */); testCommitProtocol(true /* test commit */, false /* no network failures */); testCommitProtocol(false /* test abort */, true /* with network failures */); testCommitProtocol(true /* test commit */, true /* with network failures */); st.stop();