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/**
* Copyright (C) 2018-present MongoDB, Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the Server Side Public License, version 1,
* as published by MongoDB, Inc.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* Server Side Public License for more details.
*
* You should have received a copy of the Server Side Public License
* along with this program. If not, see
* <http://www.mongodb.com/licensing/server-side-public-license>.
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the Server Side Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#include "mongo/platform/basic.h"
#include "mongo/db/write_concern_options.h"
#include "mongo/base/status.h"
#include "mongo/base/string_data.h"
#include "mongo/bson/util/bson_extract.h"
#include "mongo/db/field_parser.h"
#include "mongo/util/mongoutils/str.h"
namespace mongo {
using std::string;
namespace {
/**
* Controls how much a client cares about writes and serves as initializer for the pre-defined
* write concern options.
*
* Default is NORMAL.
*/
enum WriteConcern { W_NONE = 0, W_NORMAL = 1 };
constexpr StringData kJFieldName = "j"_sd;
constexpr StringData kFSyncFieldName = "fsync"_sd;
constexpr StringData kWFieldName = "w"_sd;
constexpr StringData kWTimeoutFieldName = "wtimeout"_sd;
constexpr StringData kGetLastErrorFieldName = "getLastError"_sd;
constexpr StringData kWOpTimeFieldName = "wOpTime"_sd;
constexpr StringData kWElectionIdFieldName = "wElectionId"_sd;
} // namespace
constexpr int WriteConcernOptions::kNoTimeout;
constexpr int WriteConcernOptions::kNoWaiting;
constexpr StringData WriteConcernOptions::kWriteConcernField;
const char WriteConcernOptions::kMajority[] = "majority";
// TODO (PM-1301): Remove once the stable Timestamp is allowed to advance past the oldest prepare
// Timestamp.
const char WriteConcernOptions::kInternalMajorityNoSnapshot[] = "internalMajorityNoSnapshot";
const BSONObj WriteConcernOptions::Default = BSONObj();
const BSONObj WriteConcernOptions::Acknowledged(BSON("w" << W_NORMAL));
const BSONObj WriteConcernOptions::Unacknowledged(BSON("w" << W_NONE));
const BSONObj WriteConcernOptions::InternalMajorityNoSnapshot(
BSON("w" << WriteConcernOptions::kInternalMajorityNoSnapshot));
const BSONObj WriteConcernOptions::Majority(BSON("w" << WriteConcernOptions::kMajority));
constexpr Seconds WriteConcernOptions::kWriteConcernTimeoutSystem;
constexpr Seconds WriteConcernOptions::kWriteConcernTimeoutMigration;
constexpr Seconds WriteConcernOptions::kWriteConcernTimeoutSharding;
constexpr Seconds WriteConcernOptions::kWriteConcernTimeoutUserCommand;
WriteConcernOptions::WriteConcernOptions(int numNodes, SyncMode sync, int timeout)
: WriteConcernOptions(numNodes, sync, Milliseconds(timeout)) {}
WriteConcernOptions::WriteConcernOptions(const std::string& mode, SyncMode sync, int timeout)
: WriteConcernOptions(mode, sync, Milliseconds(timeout)) {}
WriteConcernOptions::WriteConcernOptions(int numNodes, SyncMode sync, Milliseconds timeout)
: syncMode(sync), wNumNodes(numNodes), wTimeout(durationCount<Milliseconds>(timeout)) {}
WriteConcernOptions::WriteConcernOptions(const std::string& mode,
SyncMode sync,
Milliseconds timeout)
: syncMode(sync), wNumNodes(0), wMode(mode), wTimeout(durationCount<Milliseconds>(timeout)) {}
Status WriteConcernOptions::parse(const BSONObj& obj) {
reset();
if (obj.isEmpty()) {
return Status(ErrorCodes::FailedToParse, "write concern object cannot be empty");
}
BSONElement jEl;
BSONElement fsyncEl;
BSONElement wEl;
for (auto e : obj) {
const auto fieldName = e.fieldNameStringData();
if (fieldName == kJFieldName) {
jEl = e;
if (!jEl.isNumber() && jEl.type() != Bool) {
return Status(ErrorCodes::FailedToParse, "j must be numeric or a boolean value");
}
} else if (fieldName == kFSyncFieldName) {
fsyncEl = e;
if (!fsyncEl.isNumber() && fsyncEl.type() != Bool) {
return Status(ErrorCodes::FailedToParse,
"fsync must be numeric or a boolean value");
}
} else if (fieldName == kWFieldName) {
wEl = e;
} else if (fieldName == kWTimeoutFieldName) {
wTimeout = e.numberInt();
} else if (fieldName == kWElectionIdFieldName) {
// Ignore.
} else if (fieldName == kWOpTimeFieldName) {
// Ignore.
} else if (fieldName.equalCaseInsensitive(kGetLastErrorFieldName)) {
// Ignore GLE field.
} else {
return Status(ErrorCodes::FailedToParse,
str::stream() << "unrecognized write concern field: " << fieldName);
}
}
const bool j = jEl.trueValue();
const bool fsync = fsyncEl.trueValue();
if (j && fsync)
return Status(ErrorCodes::FailedToParse, "fsync and j options cannot be used together");
if (j) {
syncMode = SyncMode::JOURNAL;
} else if (fsync) {
syncMode = SyncMode::FSYNC;
} else if (!jEl.eoo()) {
syncMode = SyncMode::NONE;
}
if (wEl.isNumber()) {
wNumNodes = wEl.numberInt();
usedDefaultW = false;
} else if (wEl.type() == String) {
wMode = wEl.valuestrsafe();
usedDefaultW = false;
} else if (wEl.eoo() || wEl.type() == jstNULL || wEl.type() == Undefined) {
wNumNodes = 1;
} else {
return Status(ErrorCodes::FailedToParse, "w has to be a number or a string");
}
return Status::OK();
}
WriteConcernOptions WriteConcernOptions::deserializerForIDL(const BSONObj& obj) {
WriteConcernOptions writeConcernOptions;
uassertStatusOK(writeConcernOptions.parse(obj));
return writeConcernOptions;
}
StatusWith<WriteConcernOptions> WriteConcernOptions::extractWCFromCommand(
const BSONObj& cmdObj, const WriteConcernOptions& defaultWC) {
WriteConcernOptions writeConcern = defaultWC;
writeConcern.usedDefault = true;
writeConcern.usedDefaultW = true;
if (writeConcern.wNumNodes == 0 && writeConcern.wMode.empty()) {
writeConcern.wNumNodes = 1;
}
// Return the default write concern if no write concern is provided. We check for the existence
// of the write concern field up front in order to avoid the expense of constructing an error
// status in bsonExtractTypedField() below.
if (!cmdObj.hasField(kWriteConcernField)) {
return writeConcern;
}
BSONElement writeConcernElement;
Status wcStatus =
bsonExtractTypedField(cmdObj, kWriteConcernField, Object, &writeConcernElement);
if (!wcStatus.isOK()) {
return wcStatus;
}
BSONObj writeConcernObj = writeConcernElement.Obj();
// Empty write concern is interpreted to default.
if (writeConcernObj.isEmpty()) {
return writeConcern;
}
wcStatus = writeConcern.parse(writeConcernObj);
writeConcern.usedDefault = false;
if (!wcStatus.isOK()) {
return wcStatus;
}
return writeConcern;
}
BSONObj WriteConcernOptions::toBSON() const {
BSONObjBuilder builder;
if (wMode.empty()) {
builder.append("w", wNumNodes);
} else {
builder.append("w", wMode);
}
if (syncMode == SyncMode::FSYNC) {
builder.append("fsync", true);
} else if (syncMode == SyncMode::JOURNAL) {
builder.append("j", true);
} else if (syncMode == SyncMode::NONE) {
builder.append("j", false);
}
builder.append("wtimeout", wTimeout);
return builder.obj();
}
bool WriteConcernOptions::shouldWaitForOtherNodes() const {
return !wMode.empty() || wNumNodes > 1;
}
} // namespace mongo
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