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/**
* Implements the sessions api for the shell.
*/
var {
DriverSession, SessionOptions, _DummyDriverSession, _DelegatingDriverSession,
} = (function() {
"use strict";
function SessionOptions(rawOptions = {}) {
let _readPreference = rawOptions.readPreference;
let _readConcern = rawOptions.readConcern;
let _writeConcern = rawOptions.writeConcern;
const _initialClusterTime = rawOptions.initialClusterTime;
const _initialOperationTime = rawOptions.initialOperationTime;
let _causalConsistency = rawOptions.causalConsistency;
let _retryWrites = rawOptions.retryWrites;
this.getReadPreference = function getReadPreference() {
return _readPreference;
};
this.setReadPreference = function setReadPreference(readPreference) {
_readPreference = readPreference;
};
this.getReadConcern = function getReadConcern() {
return _readConcern;
};
this.setReadConcern = function setReadConcern(readConcern) {
_readConcern = readConcern;
};
this.getWriteConcern = function getWriteConcern() {
return _writeConcern;
};
this.setWriteConcern = function setWriteConcern(writeConcern) {
if (!(writeConcern instanceof WriteConcern)) {
writeConcern = new WriteConcern(writeConcern);
}
_writeConcern = writeConcern;
};
this.getInitialClusterTime = function getInitialClusterTime() {
return _initialClusterTime;
};
this.getInitialOperationTime = function getInitialOperationTime() {
return _initialOperationTime;
};
this.isCausalConsistency = function isCausalConsistency() {
return _causalConsistency;
};
this.setCausalConsistency = function setCausalConsistency(causalConsistency = true) {
_causalConsistency = causalConsistency;
};
this.shouldRetryWrites = function shouldRetryWrites() {
return _retryWrites;
};
this.setRetryWrites = function setRetryWrites(retryWrites = true) {
_retryWrites = retryWrites;
};
}
function SessionAwareClient(client) {
const kWireVersionSupportingLogicalSession = 6;
const kWireVersionSupportingCausalConsistency = 6;
const kWireVersionSupportingRetryableWrites = 6;
this.getReadPreference = function getReadPreference(driverSession) {
const sessionOptions = driverSession.getOptions();
if (sessionOptions.getReadPreference() !== undefined) {
return sessionOptions.getReadPreference();
}
return client.getReadPref();
};
this.getReadConcern = function getReadConcern(driverSession) {
const sessionOptions = driverSession.getOptions();
if (sessionOptions.getReadConcern() !== undefined) {
return sessionOptions.getReadConcern();
}
if (client.getReadConcern() !== undefined) {
return {level: client.getReadConcern()};
}
return null;
};
this.getWriteConcern = function getWriteConcern(driverSession) {
const sessionOptions = driverSession.getOptions();
if (sessionOptions.getWriteConcern() !== undefined) {
return sessionOptions.getWriteConcern();
}
return client.getWriteConcern();
};
function serverSupports(wireVersion) {
return client.getMinWireVersion() <= wireVersion &&
wireVersion <= client.getMaxWireVersion();
}
const kCommandsThatSupportReadConcern = new Set([
"aggregate",
"count",
"distinct",
"explain",
"find",
"geoNear",
"geoSearch",
"group",
"mapReduce",
"mapreduce",
"parallelCollectionScan",
]);
function canUseReadConcern(cmdObj) {
let cmdName = Object.keys(cmdObj)[0];
// If the command is in a wrapped form, then we look for the actual command name inside
// the query/$query object.
let cmdObjUnwrapped = cmdObj;
if (cmdName === "query" || cmdName === "$query") {
cmdObjUnwrapped = cmdObj[cmdName];
cmdName = Object.keys(cmdObjUnwrapped)[0];
}
if (!kCommandsThatSupportReadConcern.has(cmdName)) {
return false;
}
if (cmdName === "explain") {
return kCommandsThatSupportReadConcern.has(Object.keys(cmdObjUnwrapped.explain)[0]);
}
return true;
}
function gossipClusterTime(cmdObj, clusterTime) {
cmdObj = Object.assign({}, cmdObj);
const cmdName = Object.keys(cmdObj)[0];
// If the command is in a wrapped form, then we look for the actual command object
// inside the query/$query object.
let cmdObjUnwrapped = cmdObj;
if (cmdName === "query" || cmdName === "$query") {
cmdObj[cmdName] = Object.assign({}, cmdObj[cmdName]);
cmdObjUnwrapped = cmdObj[cmdName];
}
if (!cmdObjUnwrapped.hasOwnProperty("$clusterTime")) {
cmdObjUnwrapped.$clusterTime = clusterTime;
}
return cmdObj;
}
function injectAfterClusterTime(cmdObj, operationTime) {
cmdObj = Object.assign({}, cmdObj);
if (operationTime !== undefined) {
const cmdName = Object.keys(cmdObj)[0];
// If the command is in a wrapped form, then we look for the actual command object
// inside the query/$query object.
let cmdObjUnwrapped = cmdObj;
if (cmdName === "query" || cmdName === "$query") {
cmdObj[cmdName] = Object.assign({}, cmdObj[cmdName]);
cmdObjUnwrapped = cmdObj[cmdName];
}
cmdObjUnwrapped.readConcern = Object.assign({}, cmdObjUnwrapped.readConcern);
const readConcern = cmdObjUnwrapped.readConcern;
if (!readConcern.hasOwnProperty("afterClusterTime")) {
readConcern.afterClusterTime = operationTime;
}
}
return cmdObj;
}
function isNonNullObject(obj) {
return typeof obj === "object" && obj !== null;
}
function prepareCommandRequest(driverSession, cmdObj) {
if (serverSupports(kWireVersionSupportingLogicalSession)) {
cmdObj = driverSession._serverSession.injectSessionId(cmdObj);
}
if (serverSupports(kWireVersionSupportingCausalConsistency) &&
(client.isReplicaSetMember() || client.isMongos()) &&
!jsTest.options().skipGossipingClusterTime) {
// The `clientClusterTime` is the highest clusterTime observed by any connection
// within this mongo shell.
const clientClusterTime = client.getClusterTime();
// The `sessionClusterTime` is the highest clusterTime tracked by the
// `driverSession` session and may lag behind `clientClusterTime` if operations on
// other sessions or connections are advancing the clusterTime.
const sessionClusterTime = driverSession.getClusterTime();
// We gossip the greater of the client's clusterTime and the session's clusterTime.
// If this is the first command being sent on this connection and/or session, then
// it's possible that either clusterTime hasn't been initialized yet. Additionally,
// if the user specified a malformed clusterTime as part of initialClusterTime, then
// we want the server to be the one to reject it and therefore write our comparisons
// using bsonWoCompare() accordingly.
if (isNonNullObject(clientClusterTime) || isNonNullObject(sessionClusterTime)) {
let clusterTimeToGossip;
if (!isNonNullObject(sessionClusterTime)) {
clusterTimeToGossip = clientClusterTime;
} else if (!isNonNullObject(clientClusterTime)) {
clusterTimeToGossip = sessionClusterTime;
} else {
clusterTimeToGossip =
(bsonWoCompare({_: clientClusterTime.clusterTime},
{_: sessionClusterTime.clusterTime}) >= 0)
? clientClusterTime
: sessionClusterTime;
}
cmdObj = gossipClusterTime(cmdObj, clusterTimeToGossip);
}
}
if (serverSupports(kWireVersionSupportingCausalConsistency) &&
(driverSession.getOptions().isCausalConsistency() ||
client.isCausalConsistency()) &&
canUseReadConcern(cmdObj)) {
// `driverSession._operationTime` is the smallest time needed for performing a
// causally consistent read using the current session. Note that
// `client.getClusterTime()` is no smaller than the operation time and would
// therefore only be less efficient to wait until.
cmdObj = injectAfterClusterTime(cmdObj, driverSession._operationTime);
}
if (jsTest.options().alwaysInjectTransactionNumber &&
serverSupports(kWireVersionSupportingRetryableWrites) &&
driverSession.getOptions().shouldRetryWrites() &&
driverSession._serverSession.canRetryWrites(cmdObj)) {
cmdObj = driverSession._serverSession.assignTransactionNumber(cmdObj);
}
return cmdObj;
}
function processCommandResponse(driverSession, res) {
if (res.hasOwnProperty("operationTime") &&
bsonWoCompare({_: res.operationTime}, {_: driverSession._operationTime}) > 0) {
driverSession._operationTime = res.operationTime;
}
if (res.hasOwnProperty("$clusterTime")) {
client.setClusterTime(res.$clusterTime);
}
}
function runClientFunctionWithRetries(
driverSession, cmdObj, clientFunction, clientFunctionArguments) {
let cmdName = Object.keys(cmdObj)[0];
// If the command is in a wrapped form, then we look for the actual command object
// inside the query/$query object.
if (cmdName === "query" || cmdName === "$query") {
cmdObj = cmdObj[cmdName];
cmdName = Object.keys(cmdObj)[0];
}
let numRetries =
(cmdObj.hasOwnProperty("txnNumber") && !jsTest.options().skipRetryOnNetworkError)
? 1
: 0;
do {
try {
return clientFunction.apply(client, clientFunctionArguments);
} catch (e) {
// TODO: Should we run an explicit "isMaster" command in order to compare the
// wire version of the server after we reconnect to it?
if (!isNetworkError(e) || numRetries === 0) {
throw e;
}
}
--numRetries;
} while (numRetries >= 0);
}
this.runCommand = function runCommand(driverSession, dbName, cmdObj, options) {
cmdObj = prepareCommandRequest(driverSession, cmdObj);
const res = runClientFunctionWithRetries(
driverSession, cmdObj, client.runCommand, [dbName, cmdObj, options]);
processCommandResponse(driverSession, res);
return res;
};
this.runCommandWithMetadata = function runCommandWithMetadata(
driverSession, dbName, metadata, cmdObj) {
cmdObj = prepareCommandRequest(driverSession, cmdObj);
const res = runClientFunctionWithRetries(
driverSession, cmdObj, client.runCommandWithMetadata, [dbName, metadata, cmdObj]);
processCommandResponse(driverSession, res);
return res;
};
}
function ServerSession(client) {
let _lastUsed = new Date();
let _nextTxnNum = 0;
this.client = new SessionAwareClient(client);
this.handle = client._startSession();
this.getLastUsed = function getLastUsed() {
return _lastUsed;
};
function updateLastUsed() {
_lastUsed = new Date();
}
this.injectSessionId = function injectSessionId(cmdObj) {
cmdObj = Object.assign({}, cmdObj);
const cmdName = Object.keys(cmdObj)[0];
// If the command is in a wrapped form, then we look for the actual command object
// inside the query/$query object.
let cmdObjUnwrapped = cmdObj;
if (cmdName === "query" || cmdName === "$query") {
cmdObj[cmdName] = Object.assign({}, cmdObj[cmdName]);
cmdObjUnwrapped = cmdObj[cmdName];
}
if (!cmdObjUnwrapped.hasOwnProperty("lsid")) {
cmdObjUnwrapped.lsid = this.handle.getId();
// We consider the session to still be in use by the client any time the session id
// is injected into the command object as part of making a request.
updateLastUsed();
}
return cmdObj;
};
this.assignTransactionNumber = function assignTransactionNumber(cmdObj) {
cmdObj = Object.assign({}, cmdObj);
const cmdName = Object.keys(cmdObj)[0];
// If the command is in a wrapped form, then we look for the actual command object
// inside the query/$query object.
let cmdObjUnwrapped = cmdObj;
if (cmdName === "query" || cmdName === "$query") {
cmdObj[cmdName] = Object.assign({}, cmdObj[cmdName]);
cmdObjUnwrapped = cmdObj[cmdName];
}
if (!cmdObjUnwrapped.hasOwnProperty("txnNumber")) {
// Since there's no native support for adding NumberLong instances and getting back
// another NumberLong instance, converting from a 64-bit floating-point value to a
// 64-bit integer value will overflow at 2**53.
cmdObjUnwrapped.txnNumber = new NumberLong(_nextTxnNum);
++_nextTxnNum;
}
return cmdObj;
};
this.canRetryWrites = function canRetryWrites(cmdObj) {
let cmdName = Object.keys(cmdObj)[0];
// If the command is in a wrapped form, then we look for the actual command name inside
// the query/$query object.
if (cmdName === "query" || cmdName === "$query") {
cmdObj = cmdObj[cmdName];
cmdName = Object.keys(cmdObj)[0];
}
if (cmdName === "insert") {
if (!Array.isArray(cmdObj.documents)) {
// The command object is malformed, so we'll just leave it as-is and let the
// server reject it.
return false;
}
if (cmdObj.documents.length === 1) {
// Single-statement operations (e.g. insertOne()) can be retried.
return true;
}
// Multi-statement operations (e.g. insertMany()) can be retried if they are
// executed in order by the server.
return cmdObj.ordered ? true : false;
} else if (cmdName === "update") {
if (!Array.isArray(cmdObj.updates)) {
// The command object is malformed, so we'll just leave it as-is and let the
// server reject it.
return false;
}
const hasMultiUpdate = cmdObj.updates.some(updateOp => updateOp.multi);
if (hasMultiUpdate) {
// Operations that modify multiple documents (e.g. updateMany()) cannot be
// retried.
return false;
}
if (cmdObj.updates.length === 1) {
// Single-statement operations that modify a single document (e.g. updateOne())
// can be retried.
return true;
}
// Multi-statement operations that each modify a single document (e.g. bulkWrite())
// can be retried if they are executed in order by the server.
return cmdObj.ordered ? true : false;
} else if (cmdName === "delete") {
if (!Array.isArray(cmdObj.deletes)) {
// The command object is malformed, so we'll just leave it as-is and let the
// server reject it.
return false;
}
// We use bsonWoCompare() in order to handle cases where the limit is specified as a
// NumberInt() or NumberLong() instance.
const hasMultiDelete = cmdObj.deletes.some(
deleteOp => bsonWoCompare({_: deleteOp.limit}, {_: 0}) === 0);
if (hasMultiDelete) {
// Operations that modify multiple documents (e.g. deleteMany()) cannot be
// retried.
return false;
}
if (cmdObj.deletes.length === 1) {
// Single-statement operations that modify a single document (e.g. deleteOne())
// can be retried.
return true;
}
// Multi-statement operations that each modify a single document (e.g. bulkWrite())
// can be retried if they are executed in order by the server.
return cmdObj.ordered ? true : false;
} else if (cmdName === "findAndModify" || cmdName === "findandmodify") {
// Operations that modify a single document (e.g. findOneAndUpdate()) can be
// retried.
return true;
}
return false;
};
}
function makeDriverSessionConstructor(implMethods) {
return function(client, options = {}) {
let _options = options;
let _hasEnded = false;
if (!(_options instanceof SessionOptions)) {
_options = new SessionOptions(_options);
}
this._serverSession = implMethods.createServerSession(client);
this._operationTime = _options.getInitialOperationTime();
if (_options.getInitialClusterTime() !== undefined) {
client.setClusterTime(_options.getInitialClusterTime());
}
this.getClient = function getClient() {
return client;
};
this._getSessionAwareClient = function _getSessionAwareClient() {
return this._serverSession.client;
};
this.getOptions = function getOptions() {
return _options;
};
this.getOperationTime = function getOperationTime() {
return this._operationTime;
};
this.getClusterTime = function getClusterTime() {
return client.getClusterTime();
};
this.getDatabase = function getDatabase(dbName) {
const db = client.getDB(dbName);
db._session = this;
return db;
};
this.hasEnded = function hasEnded() {
return _hasEnded;
};
this.endSession = function endSession() {
if (this._hasEnded) {
return;
}
this._hasEnded = true;
implMethods.endSession(this._serverSession);
};
};
}
const DriverSession = makeDriverSessionConstructor({
createServerSession: function createServerSession(client) {
return new ServerSession(client);
},
endSession: function endSession(serverSession) {
serverSession.handle.end();
},
});
function DelegatingDriverSession(client, originalSession) {
this._serverSession = originalSession._serverSession;
Object.defineProperty(this, "_operationTime", {
get: function() {
return originalSession._operationTime;
},
set: function(operationTime) {
originalSession._operationTime = operationTime;
},
});
const sessionAwareClient = new SessionAwareClient(client);
this.getClient = function() {
return client;
};
this._getSessionAwareClient = function() {
return sessionAwareClient;
};
this.getOptions = function() {
return originalSession.getOptions();
};
this.getOperationTime = function getOperationTime() {
return this._operationTime;
};
this.getClusterTime = function getClusterTime() {
return originalSession.getClusterTime();
};
this.getDatabase = function(dbName) {
const db = client.getDB(dbName);
db._session = this;
return db;
};
this.hasEnded = function() {
return originalSession.hasEnded();
};
this.endSession = function() {
return originalSession.endSession();
};
}
const DummyDriverSession = makeDriverSessionConstructor({
createServerSession: function createServerSession(client) {
return {
client: new SessionAwareClient(client),
injectSessionId: function injectSessionId(cmdObj) {
return cmdObj;
},
assignTransactionNumber: function assignTransactionNumber(cmdObj) {
return cmdObj;
},
canRetryWrites: function canRetryWrites(cmdObj) {
return false;
},
};
},
endSession: function endSession(serverSession) {},
});
// We don't actually put anything on DriverSession.prototype, but this way
// `session instanceof DriverSession` will work for DummyDriverSession instances.
DummyDriverSession.prototype = Object.create(DriverSession.prototype);
DummyDriverSession.prototype.constructor = DriverSession;
return {
DriverSession: DriverSession,
SessionOptions: SessionOptions,
_DummyDriverSession: DummyDriverSession,
_DelegatingDriverSession: DelegatingDriverSession,
};
})();
|