1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
|
/**
* Test that transactions are only allowed on primaries, and prohibited from running on secondaries.
*
* @tags: [uses_transactions]
*/
(function() {
"use strict";
// In 4.0, we allow read-only transactions on secondaries when test commands are enabled, so we
// disable them in this test, to test that transactions on secondaries will be disallowed
// for production users.
TestData.enableTestCommands = false;
TestData.roleGraphInvalidationIsFatal = false;
TestData.authenticationDatabase = "local";
const dbName = "test";
const collName = "transactions_only_allowed_on_primaries";
// Start up the replica set. We want a stable topology, so make the secondary unelectable.
const replTest = new ReplSetTest({name: collName, nodes: 2});
replTest.startSet();
let config = replTest.getReplSetConfig();
config.members[1].priority = 0;
replTest.initiate(config);
const primary = replTest.getPrimary();
const secondary = replTest.getSecondary();
// Set slaveOk=true so that normal read commands would be allowed on the secondary.
secondary.setSlaveOk(true);
// Create a test collection that we can run commands against.
const primaryDB = primary.getDB(dbName);
assert.commandWorked(primary.getDB(dbName).createCollection(collName));
assert.commandWorked(primaryDB.runCommand({
createIndexes: collName,
indexes: [
{name: "geo_2d", key: {geo: "2d"}},
{key: {haystack: "geoHaystack", a: 1}, name: "haystack_geo", bucketSize: 1}
]
}));
replTest.awaitLastOpCommitted();
/**
* Verify that all given commands are disallowed from starting a transaction on a secondary by
* checking that each command fails with the expected error code.
*/
function testCommands(session, commands, expectedErrorCode, readPref) {
const sessionDb = session.getDatabase(dbName);
for (let i = 0; i < commands.length; i++) {
session.startTransaction();
// Use a read preference that would normally allow read commands to run on secondaries.
if (readPref !== null) {
session.getOptions().setReadPreference(readPref);
}
const cmdObject = commands[i];
jsTestLog("Trying to start transaction on secondary with command: " + tojson(cmdObject));
assert.commandFailedWithCode(sessionDb.runCommand(cmdObject), expectedErrorCode);
// Call abort for good measure, even though the transaction should have already been
// aborted on the server.
assert.commandFailedWithCode(session.abortTransaction_forTesting(),
ErrorCodes.NotWritablePrimary);
}
}
//
// Make sure transactions are disallowed on secondaries.
//
// Initiate a session on the secondary.
const sessionOptions = {
causalConsistency: false
};
const secondarySession = secondary.getDB(dbName).getMongo().startSession(sessionOptions);
// Test read commands that are supported in transactions.
let readCommands = [
{find: collName},
{aggregate: collName, pipeline: [{$project: {_id: 1}}], cursor: {}},
{distinct: collName, key: "_id"},
{geoSearch: collName, near: [0, 0]}
];
jsTestLog("Testing read commands.");
// Make sure read commands can not start transactions with any supported read preference.
testCommands(secondarySession, readCommands, ErrorCodes.NotWritablePrimary, "secondary");
testCommands(secondarySession, readCommands, ErrorCodes.NotWritablePrimary, "secondaryPreferred");
testCommands(secondarySession, readCommands, ErrorCodes.NotWritablePrimary, "primaryPreferred");
testCommands(secondarySession, readCommands, ErrorCodes.NotWritablePrimary, null);
// Test one write command. Normal write commands should already be
// disallowed on secondaries so we don't test them exhaustively here.
let writeCommands = [{insert: collName, documents: [{_id: 0}]}];
jsTestLog("Testing write commands.");
testCommands(secondarySession, writeCommands, ErrorCodes.NotWritablePrimary, "secondary");
secondarySession.endSession();
//
// Make sure transactions are allowed on primaries with any valid read preference.
//
const primarySession = primary.getDB(dbName).getMongo().startSession(sessionOptions);
const primarySessionDb = primarySession.getDatabase(dbName);
primarySession.startTransaction();
assert.commandWorked(
primarySessionDb.runCommand({find: collName, $readPreference: {mode: "primary"}}));
assert.commandWorked(primarySession.commitTransaction_forTesting());
primarySession.startTransaction();
assert.commandWorked(
primarySessionDb.runCommand({find: collName, $readPreference: {mode: "primaryPreferred"}}));
assert.commandWorked(primarySession.commitTransaction_forTesting());
primarySession.startTransaction();
assert.commandWorked(
primarySessionDb.runCommand({find: collName, $readPreference: {mode: "secondaryPreferred"}}));
assert.commandWorked(primarySession.commitTransaction_forTesting());
primarySession.startTransaction();
assert.commandWorked(
primarySessionDb.runCommand({find: collName, $readPreference: {mode: "nearest"}}));
assert.commandWorked(primarySession.commitTransaction_forTesting());
primarySession.endSession();
replTest.stopSet();
}());
|
