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/**
* Tests that pre-images are not recorded for the temporal resharding collection even if it has
* pre-image recording enabled and verifies that pre-and-post-images are available for all change
* stream events - ones that happened before, during, and after resharding of the collection.
*
* @tags: [
* requires_fcv_60,
* uses_change_streams,
* assumes_unsharded_collection,
* assumes_read_preference_unchanged,
* ]
*/
(function() {
"use strict";
load("jstests/libs/discover_topology.js");
load("jstests/sharding/libs/resharding_test_fixture.js");
// Create a resharding test instance and enable higher frequency no-ops to avoid test case from
// failing because of timeout while waiting for next change stream event.
const reshardingTest = new ReshardingTest(
{reshardInPlace: false, periodicNoopIntervalSecs: 1, writePeriodicNoops: true});
reshardingTest.setup();
const donorShardNames = reshardingTest.donorShardNames;
const recipientShardNames = reshardingTest.recipientShardNames;
const collectionName = "test.whileResharding";
// Create a sharded collection with 'oldShardKey' as the shard key.
const coll = reshardingTest.createShardedCollection({
ns: collectionName,
shardKeyPattern: {oldShardKey: 1},
chunks: [
{min: {oldShardKey: MinKey}, max: {oldShardKey: MaxKey}, shard: donorShardNames[0]},
],
});
const mongos = coll.getMongo();
const topology = DiscoverTopology.findConnectedNodes(mongos);
const donorConn = new Mongo(topology.shards[donorShardNames[0]].primary);
const recipientConn = new Mongo(topology.shards[recipientShardNames[0]].primary);
// Verifies that expected documents are present in the pre-image collection at the specified shard.
function verifyPreImages(conn, expectedPreImageDocuments) {
const preImageDocuments =
conn.getDB("config").getCollection("system.preimages").find().toArray();
assert.eq(preImageDocuments.length, expectedPreImageDocuments.length, preImageDocuments);
for (let idx = 0; idx < preImageDocuments.length; idx++) {
assert.eq(preImageDocuments[idx].preImage,
expectedPreImageDocuments[idx],
preImageDocuments[idx].preImage);
}
}
// Verifies that the change streams cursor 'csCursor' observes the expected events.
function verifyChangeStreamEvents(csCursor, events) {
events.forEach(expectedEvent => {
assert.soon(() => csCursor.hasNext());
const event = csCursor.next();
assert.eq(event.operationType, expectedEvent.opType, event);
assert.eq(event.documentKey._id, expectedEvent.id, event);
assert.eq(event.fullDocumentBeforeChange.annotation, expectedEvent.prevAnnotation, event);
if (event.operationType == "update") {
assert.eq(event.fullDocument.annotation, expectedEvent.curAnnotation, event);
}
});
}
// Enable recording of pre-images in the collection.
assert.commandWorked(coll.getDB().runCommand(
{collMod: "whileResharding", changeStreamPreAndPostImages: {enabled: true}}));
// Insert some documents before resharding the collection so that there is data to clone.
assert.commandWorked(coll.insert([
{_id: 0, annotation: "pre-resharding-insert", oldShardKey: 0, newShardKey: 2},
{_id: 1, annotation: "pre-resharding-insert", oldShardKey: 1, newShardKey: 3},
{_id: 2, annotation: "pre-resharding-txn", oldShardKey: 1, newShardKey: 3},
{_id: 3, annotation: "pre-resharding-txn", oldShardKey: 1, newShardKey: 3},
]));
// Verify that 'insert' operations does not record any pre-images.
verifyPreImages(donorConn, []);
verifyPreImages(recipientConn, []);
// Open a change stream to record all events in the collection.
const csCursor = coll.watch([], {fullDocument: "required", fullDocumentBeforeChange: "required"});
// Update documents to ensure that pre-images for these documents are recorded.
assert.commandWorked(coll.update({_id: 0}, {$set: {annotation: "pre-resharding-update"}}));
assert.commandWorked(coll.update({_id: 1}, {$set: {annotation: "pre-resharding-update"}}));
// Verify that pre-images are recorded for 'update' operations on the donor shard.
verifyPreImages(donorConn, [
{_id: 0, annotation: "pre-resharding-insert", oldShardKey: 0, newShardKey: 2},
{_id: 1, annotation: "pre-resharding-insert", oldShardKey: 1, newShardKey: 3}
]);
verifyPreImages(recipientConn, []);
// Reshard the collection with 'newShardKey' as the new shard key.
reshardingTest.withReshardingInBackground(
{
newShardKeyPattern: {newShardKey: 1},
newChunks: [
{min: {newShardKey: MinKey}, max: {newShardKey: MaxKey}, shard: recipientShardNames[0]}
],
},
() => {
// We wait until cloneTimestamp has been chosen to guarantee that any subsequent writes will
// be applied by the ReshardingOplogApplier.
reshardingTest.awaitCloneTimestampChosen();
assert.commandWorked(
coll.update({_id: 0}, {$set: {annotation: "during-resharding-update"}}));
assert.commandWorked(
coll.update({_id: 1}, {$set: {annotation: "during-resharding-update"}}));
assert.commandWorked(coll.remove({_id: 1}, {justOne: true}));
// Perform some operations in a transaction.
assert.retryNoExcept(
() => {
const session = coll.getDB().getMongo().startSession();
const sessionDB = session.getDatabase(coll.getDB().getName());
const sessionColl = sessionDB.getCollection(coll.getName());
session.startTransaction();
assert.commandWorked(sessionColl.update(
{_id: 2}, {$set: {annotation: "during-resharding-txn-update"}}));
assert.commandWorked(sessionColl.remove({_id: 3}, {justOne: true}));
session.commitTransaction_forTesting();
return true;
},
"Failed to execute a transaction while resharding was in progress",
10 /*num_attempts*/,
100 /*intervalMS*/);
});
// Verify that after the resharding is complete, the pre-image collection exists on the recipient
// shard with clustered-index enabled.
const preImageCollInfo =
recipientConn.getDB("config").getCollectionInfos({name: "system.preimages"});
assert.eq(preImageCollInfo.length, 1, preImageCollInfo);
assert(preImageCollInfo[0].options.hasOwnProperty("clusteredIndex"), preImageCollInfo[0]);
// Update a document after resharding. The pre-image corresponding to this update should be observed
// by the recipient shard.
assert.commandWorked(coll.update({_id: 0}, {$set: {annotation: "post-resharding-update"}}));
// Verify that the donor shard contains pre-images for the update and delete operations performed
// before and during resharding and recipient shard contains pre-images from the update operation
// performed after the resharding is complete.
verifyPreImages(donorConn, [
{_id: 0, annotation: "pre-resharding-insert", oldShardKey: 0, newShardKey: 2},
{_id: 1, annotation: "pre-resharding-insert", oldShardKey: 1, newShardKey: 3},
{_id: 0, annotation: "pre-resharding-update", oldShardKey: 0, newShardKey: 2},
{_id: 1, annotation: "pre-resharding-update", oldShardKey: 1, newShardKey: 3},
{_id: 1, annotation: "during-resharding-update", oldShardKey: 1, newShardKey: 3},
{_id: 2, annotation: "pre-resharding-txn", oldShardKey: 1, newShardKey: 3},
{_id: 3, annotation: "pre-resharding-txn", oldShardKey: 1, newShardKey: 3},
]);
verifyPreImages(recipientConn,
[{_id: 0, annotation: "during-resharding-update", oldShardKey: 0, newShardKey: 2}]);
// Verify that the change stream observes the change events with required pre-images.
verifyChangeStreamEvents(csCursor, [
{
opType: "update",
id: 0,
prevAnnotation: "pre-resharding-insert",
curAnnotation: "pre-resharding-update"
},
{
opType: "update",
id: 1,
prevAnnotation: "pre-resharding-insert",
curAnnotation: "pre-resharding-update"
},
{
opType: "update",
id: 0,
prevAnnotation: "pre-resharding-update",
curAnnotation: "during-resharding-update"
},
{
opType: "update",
id: 1,
prevAnnotation: "pre-resharding-update",
curAnnotation: "during-resharding-update"
},
{opType: "delete", id: 1, prevAnnotation: "during-resharding-update"},
{
opType: "update",
id: 2,
prevAnnotation: "pre-resharding-txn",
curAnnotation: "during-resharding-txn-update"
},
{opType: "delete", id: 3, prevAnnotation: "pre-resharding-txn"},
{
opType: "update",
id: 0,
prevAnnotation: "during-resharding-update",
curAnnotation: "post-resharding-update"
},
]);
reshardingTest.teardown();
})();
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