mongo/jstests/fail_point/set_failpoint_through_set_parameter.js

/**
 * Tests that failpoints can be set via --setParameter on the command line for mongos and mongod
 * only when running with enableTestCommands=1.
 * @tags: [
 *   disables_test_commands,
 * ]
 */
import {ReplSetTest} from "jstests/libs/replsettest.js";

function assertStartupSucceeds(conn) {
    assert.commandWorked(conn.adminCommand({hello: 1}));
}

function assertStartupFails(fun) {
    assert.throws(fun, [], "Server started, when it was expected to fail");
}

let validFailpointPayload = {"mode": "alwaysOn"};
let validFailpointPayloadWithData = {"mode": "alwaysOn", "data": {x: 1}};
let invalidFailpointPayload = "notJSON";

// In order to be able connect to a mongos that starts up successfully, start a config replica
// set so that we can provide a valid config connection string to the mongos.
let configRS = new ReplSetTest({nodes: 3});
configRS.startSet({configsvr: "", storageEngine: "wiredTiger"});
configRS.initiate();

// Setting a failpoint via --setParameter fails if enableTestCommands is not on.
TestData.enableTestCommands = false;
assertStartupFails(() => MongoRunner.runMongod({setParameter: "failpoint.dummy=" + tojson(validFailpointPayload)}));
assertStartupFails(() =>
    MongoRunner.runMongos({
        setParameter: "failpoint.dummy=" + tojson(validFailpointPayload),
        configdb: configRS.getURL(),
    }),
);
TestData.enableTestCommands = true;

// Passing an invalid failpoint payload fails.
assertStartupFails(() => MongoRunner.runMongod({setParameter: "failpoint.dummy=" + tojson(invalidFailpointPayload)}));
assertStartupFails(() =>
    MongoRunner.runMongos({
        setParameter: "failpoint.dummy=" + tojson(invalidFailpointPayload),
        configdb: configRS.getURL(),
    }),
);

// Valid startup configurations succeed.
let mongod = MongoRunner.runMongod({setParameter: "failpoint.dummy=" + tojson(validFailpointPayload)});
assertStartupSucceeds(mongod);
MongoRunner.stopMongod(mongod);

let mongos = MongoRunner.runMongos({
    setParameter: "failpoint.dummy=" + tojson(validFailpointPayload),
    configdb: configRS.getURL(),
});
assertStartupSucceeds(mongos);
MongoRunner.stopMongos(mongos);

mongod = MongoRunner.runMongod({setParameter: "failpoint.dummy=" + tojson(validFailpointPayloadWithData)});
assertStartupSucceeds(mongod);

mongos = MongoRunner.runMongos({
    setParameter: "failpoint.dummy=" + tojson(validFailpointPayloadWithData),
    configdb: configRS.getURL(),
});
assertStartupSucceeds(mongos);

// The failpoint shows up with the correct data in the results of getParameter.

let res = mongod.adminCommand({getParameter: "*"});
assert.neq(null, res);
assert.neq(null, res["failpoint.dummy"]);
assert.eq(1, res["failpoint.dummy"].mode); // the 'mode' is an enum internally; 'alwaysOn' is 1
assert.eq(validFailpointPayloadWithData.data, res["failpoint.dummy"].data);

res = mongos.adminCommand({getParameter: "*"});
assert.neq(null, res);
assert.neq(null, res["failpoint.dummy"]);
assert.eq(1, res["failpoint.dummy"].mode); // the 'mode' is an enum internally; 'alwaysOn' is 1
assert.eq(validFailpointPayloadWithData.data, res["failpoint.dummy"].data);

// The failpoint cannot be set by the setParameter command.
assert.commandFailed(mongod.adminCommand({setParameter: 1, "dummy": validFailpointPayload}));
assert.commandFailed(mongos.adminCommand({setParameter: 1, "dummy": validFailpointPayload}));

// After changing the failpoint's state through the configureFailPoint command, the changes are
// reflected in the output of the getParameter command.

let newData = {x: 2};

mongod.adminCommand({configureFailPoint: "dummy", mode: "alwaysOn", data: newData});
res = mongod.adminCommand({getParameter: 1, "failpoint.dummy": 1});
assert.neq(null, res);
assert.neq(null, res["failpoint.dummy"]);
assert.eq(1, res["failpoint.dummy"].mode); // the 'mode' is an enum internally; 'alwaysOn' is 1
assert.eq(newData, res["failpoint.dummy"].data);

mongos.adminCommand({configureFailPoint: "dummy", mode: "alwaysOn", data: newData});
res = mongos.adminCommand({getParameter: 1, "failpoint.dummy": 1});
assert.neq(null, res);
assert.neq(null, res["failpoint.dummy"]);
assert.eq(1, res["failpoint.dummy"].mode); // the 'mode' is an enum internally; 'alwaysOn' is 1
assert.eq(newData, res["failpoint.dummy"].data);

MongoRunner.stopMongod(mongod);
MongoRunner.stopMongos(mongos);

// Failpoint server parameters do not show up in the output of getParameter when not running
// with enableTestCommands=1.

TestData.enableTestCommands = false;
TestData.roleGraphInvalidationIsFatal = false;

mongod = MongoRunner.runMongod();
assertStartupSucceeds(mongod);

mongos = MongoRunner.runMongos({configdb: configRS.getURL()});
assertStartupSucceeds(mongos);

// Doing getParameter for a specific failpoint fails.
assert.commandFailed(mongod.adminCommand({getParameter: 1, "failpoint.dummy": 1}));
assert.commandFailed(mongos.adminCommand({getParameter: 1, "failpoint.dummy": 1}));

// No failpoint parameters show up when listing all parameters through getParameter.
res = mongod.adminCommand({getParameter: "*"});
assert.neq(null, res);
for (var parameter in res) {
    // for-in loop valid only for top-level field checks.
    assert(!parameter.includes("failpoint."));
}

res = mongos.adminCommand({getParameter: "*"});
assert.neq(null, res);
for (var parameter in res) {
    // for-in loop valid only for top-level field checks.
    assert(!parameter.includes("failpoint."));
}

MongoRunner.stopMongod(mongod);
MongoRunner.stopMongos(mongos);
configRS.stopSet();