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/**
* @tags: [requires_journaling]
*
* Test basic read committed functionality on a secondary:
* - Updates should not be visible until they are in the blessed snapshot.
* - Updates should be visible once they are in the blessed snapshot.
*/
load("jstests/replsets/rslib.js"); // For startSetIfSupportsReadMajority.
(function() {
"use strict";
// Set up a set and grab things for later.
var name = "read_committed_on_secondary";
var replTest =
new ReplSetTest({name: name, nodes: 3, nodeOptions: {enableMajorityReadConcern: ''}});
if (!startSetIfSupportsReadMajority(replTest)) {
jsTest.log("skipping test since storage engine doesn't support committed reads");
return;
}
var nodes = replTest.nodeList();
replTest.initiate({
"_id": name,
"members": [
{"_id": 0, "host": nodes[0]},
{"_id": 1, "host": nodes[1], priority: 0},
{"_id": 2, "host": nodes[2], arbiterOnly: true}
]
});
// Get connections and collection.
var primary = replTest.getPrimary();
var secondary = replTest.liveNodes.slaves[0];
var secondaryId = replTest.getNodeId(secondary);
var dbPrimary = primary.getDB(name);
var collPrimary = dbPrimary[name];
var dbSecondary = secondary.getDB(name);
var collSecondary = dbSecondary[name];
function saveDoc(state) {
var res = dbPrimary.runCommandWithMetadata(
'update',
{
update: name,
writeConcern: {w: 2, wtimeout: 60 * 1000},
updates: [{q: {_id: 1}, u: {_id: 1, state: state}, upsert: true}],
},
{"$replData": 1});
assert.commandWorked(res.commandReply);
assert.eq(res.commandReply.writeErrors, undefined);
return res.metadata.$replData.lastOpVisible;
}
function doDirtyRead(lastOp) {
var res = collSecondary.runCommand(
'find', {"readConcern": {"level": "local", "afterOpTime": lastOp}});
assert.commandWorked(res);
return new DBCommandCursor(secondary, res).toArray()[0].state;
}
function doCommittedRead(lastOp) {
var res = collSecondary.runCommand(
'find', {"readConcern": {"level": "majority", "afterOpTime": lastOp}});
assert.commandWorked(res);
return new DBCommandCursor(secondary, res).toArray()[0].state;
}
// Do a write, wait for it to replicate, and ensure it is visible.
var op0 = saveDoc(0);
assert.eq(doDirtyRead(op0), 0);
assert.eq(doCommittedRead(op0), 0);
// Disable snapshotting on the secondary.
secondary.adminCommand({configureFailPoint: 'disableSnapshotting', mode: 'alwaysOn'});
// Do a write and ensure it is only visible to dirty reads
var op1 = saveDoc(1);
assert.eq(doDirtyRead(op1), 1);
assert.eq(doCommittedRead(op0), 0);
// Try the committed read again after sleeping to ensure it doesn't only work for queries
// immediately after the write.
sleep(1000);
assert.eq(doCommittedRead(op0), 0);
// Reenable snapshotting on the secondary and ensure that committed reads are able to see the
// new
// state.
secondary.adminCommand({configureFailPoint: 'disableSnapshotting', mode: 'off'});
assert.eq(doDirtyRead(op1), 1);
assert.eq(doCommittedRead(op1), 1);
}());
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