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/**
* 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]
*/
(function() {
'use strict';
load('jstests/sharding/libs/sharded_transactions_helpers.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 checkDecisionIs = function(coordinatorConn, lsid, txnNumber, expectedDecision) {
let coordDoc = coordinatorConn.getDB("config")
.getCollection("transaction_coordinators")
.findOne({"_id.lsid.id": lsid.id, "_id.txnNumber": txnNumber});
assert.neq(null, coordDoc);
assert.eq(expectedDecision, coordDoc.decision.decision);
if (expectedDecision === "commit") {
assert.neq(null, coordDoc.decision.commitTimestamp);
} else {
assert.eq(null, coordDoc.decision.commitTimestamp);
}
};
const checkDocumentDeleted = function(coordinatorConn, lsid, txnNumber) {
let coordDoc = coordinatorConn.getDB("config")
.getCollection("transaction_coordinators")
.findOne({"_id.lsid.id": lsid.id, "_id.txnNumber": txnNumber});
return null === coordDoc;
};
const runCommitThroughMongosInParallelShellExpectSuccess = function() {
const runCommitExpectSuccessCode = "assert.commandWorked(db.adminCommand({" +
"commitTransaction: 1," + "lsid: " + tojson(lsid) + "," + "txnNumber: NumberLong(" +
txnNumber + ")," + "stmtId: NumberInt(0)," + "autocommit: false," + "}));";
return startParallelShell(runCommitExpectSuccessCode, st.s.port);
};
const runCommitThroughMongosInParallelShellExpectAbort = function() {
const runCommitExpectSuccessCode = "assert.commandFailedWithCode(db.adminCommand({" +
"commitTransaction: 1," + "lsid: " + tojson(lsid) + "," + "txnNumber: NumberLong(" +
txnNumber + ")," + "stmtId: NumberInt(0)," + "autocommit: false," + "})," +
"ErrorCodes.NoSuchTransaction);";
return startParallelShell(runCommitExpectSuccessCode, st.s.port);
};
const startSimulatingNetworkFailures = function(connArray) {
connArray.forEach(function(conn) {
assert.commandWorked(conn.adminCommand({
configureFailPoint: "failCommand",
mode: {times: 10},
data: {
errorCode: ErrorCodes.NotMaster,
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}));
assert.commandWorked(st.s.adminCommand({movePrimary: dbName, to: 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}));
// 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.
assert.commandWorked(coordinator.adminCommand({
configureFailPoint: "hangBeforeWaitingForParticipantListWriteConcern",
mode: "alwaysOn",
}));
assert.commandWorked(coordinator.adminCommand({
configureFailPoint: "hangBeforeWaitingForDecisionWriteConcern",
mode: "alwaysOn",
}));
// Run commitTransaction through a parallel shell.
let awaitResult;
if (shouldCommit) {
awaitResult = runCommitThroughMongosInParallelShellExpectSuccess();
} else {
awaitResult = runCommitThroughMongosInParallelShellExpectAbort();
}
// Check that the coordinator wrote the participant list.
waitForFailpoint("Hit hangBeforeWaitingForParticipantListWriteConcern failpoint",
txnNumber);
checkParticipantListMatches(coordinator, lsid, txnNumber, expectedParticipantList);
assert.commandWorked(coordinator.adminCommand({
configureFailPoint: "hangBeforeWaitingForParticipantListWriteConcern",
mode: "off",
}));
// Check that the coordinator wrote the decision.
waitForFailpoint("Hit hangBeforeWaitingForDecisionWriteConcern failpoint", txnNumber);
checkParticipantListMatches(coordinator, lsid, txnNumber, expectedParticipantList);
checkDecisionIs(coordinator, lsid, txnNumber, (shouldCommit ? "commit" : "abort"));
assert.commandWorked(coordinator.adminCommand({
configureFailPoint: "hangBeforeWaitingForDecisionWriteConcern",
mode: "off",
}));
// Check that the coordinator deleted its persisted state.
awaitResult();
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.");
// Use assert.soon(), because although coordinateCommitTransaction currently blocks
// until the commit process is fully complete, it will eventually be changed to only
// block until the decision is *written*, at which point the test can pass the
// operationTime returned by coordinateCommitTransaction as 'afterClusterTime' in the
// read to ensure the read sees the transaction's writes (TODO SERVER-37165).
assert.soon(function() {
return 3 === st.s.getDB(dbName).getCollection(collName).find().itcount();
});
}
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();
})();
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