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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/query/count_request.h"
#include "mongo/db/query/query_request.h"
#include "mongo/util/mongoutils/str.h"
namespace mongo {
namespace {
const char kCmdName[] = "count";
const char kQueryField[] = "query";
const char kLimitField[] = "limit";
const char kSkipField[] = "skip";
const char kHintField[] = "hint";
const char kCollationField[] = "collation";
const char kExplainField[] = "explain";
const char kCommentField[] = "comment";
const char kMaxTimeMSField[] = "maxTimeMS";
const char kReadConcernField[] = "readConcern";
} // namespace
CountRequest::CountRequest(NamespaceString nss, BSONObj query)
: _nss(std::move(nss)), _query(query.getOwned()) {}
void CountRequest::setHint(BSONObj hint) {
_hint = hint.getOwned();
}
void CountRequest::setCollation(BSONObj collation) {
_collation = collation.getOwned();
}
StatusWith<CountRequest> CountRequest::parseFromBSON(const NamespaceString& nss,
const BSONObj& cmdObj,
bool isExplain) {
// We don't validate that "query" is a nested object due to SERVER-15456.
CountRequest request(nss, cmdObj.getObjectField(kQueryField));
// Limit
if (cmdObj[kLimitField].isNumber()) {
long long limit = cmdObj[kLimitField].numberLong();
if (limit == std::numeric_limits<long long>::min()) {
// The absolute value of the smallest long long is too large to be represented as a long
// long, so we fail to parse such count commands.
return Status(ErrorCodes::BadValue, "limit value for count cannot be min long");
}
// For counts, limit and -limit mean the same thing.
if (limit < 0) {
limit = -limit;
}
request.setLimit(limit);
} else if (cmdObj[kLimitField].ok()) {
return Status(ErrorCodes::BadValue, "limit value is not a valid number");
}
// Skip
if (cmdObj[kSkipField].isNumber()) {
long long skip = cmdObj[kSkipField].numberLong();
if (skip < 0) {
return Status(ErrorCodes::BadValue, "skip value is negative in count query");
}
request.setSkip(skip);
} else if (cmdObj[kSkipField].ok()) {
return Status(ErrorCodes::BadValue, "skip value is not a valid number");
}
// maxTimeMS
if (cmdObj[kMaxTimeMSField].ok()) {
auto maxTimeMS = QueryRequest::parseMaxTimeMS(cmdObj[kMaxTimeMSField]);
if (!maxTimeMS.isOK()) {
return maxTimeMS.getStatus();
}
request.setMaxTimeMS(static_cast<unsigned int>(maxTimeMS.getValue()));
}
// Hint
if (BSONType::Object == cmdObj[kHintField].type()) {
request.setHint(cmdObj[kHintField].Obj());
} else if (String == cmdObj[kHintField].type()) {
const std::string hint = cmdObj.getStringField(kHintField);
request.setHint(BSON("$hint" << hint));
}
// Collation
if (BSONType::Object == cmdObj[kCollationField].type()) {
request.setCollation(cmdObj[kCollationField].Obj());
} else if (cmdObj[kCollationField].ok()) {
return Status(ErrorCodes::BadValue, "collation value is not a document");
}
// readConcern
if (BSONType::Object == cmdObj[kReadConcernField].type()) {
request.setReadConcern(cmdObj[kReadConcernField].Obj());
} else if (cmdObj[kReadConcernField].ok()) {
return Status(ErrorCodes::BadValue, "readConcern value is not a document");
}
// unwrappedReadPref
if (BSONType::Object == cmdObj[QueryRequest::kUnwrappedReadPrefField].type()) {
request.setUnwrappedReadPref(cmdObj[QueryRequest::kUnwrappedReadPrefField].Obj());
} else if (cmdObj[QueryRequest::kUnwrappedReadPrefField].ok()) {
return Status(ErrorCodes::BadValue, "readPreference value is not a document");
}
// Comment
if (BSONType::String == cmdObj[kCommentField].type()) {
request.setComment(cmdObj[kCommentField].valueStringData());
} else if (cmdObj[kCommentField].ok()) {
return Status(ErrorCodes::BadValue, "comment value is not a string");
}
// Explain
request.setExplain(isExplain);
return request;
}
StatusWith<BSONObj> CountRequest::asAggregationCommand() const {
BSONObjBuilder aggregationBuilder;
aggregationBuilder.append("aggregate", _nss.coll());
// Build an aggregation pipeline that performs the counting. We add stages that satisfy the
// query, skip and limit before finishing with the actual $count stage.
BSONArrayBuilder pipelineBuilder(aggregationBuilder.subarrayStart("pipeline"));
if (!_query.isEmpty()) {
BSONObjBuilder matchBuilder(pipelineBuilder.subobjStart());
matchBuilder.append("$match", _query);
matchBuilder.doneFast();
}
if (_skip) {
BSONObjBuilder skipBuilder(pipelineBuilder.subobjStart());
skipBuilder.append("$skip", *_skip);
skipBuilder.doneFast();
}
if (_limit) {
BSONObjBuilder limitBuilder(pipelineBuilder.subobjStart());
limitBuilder.append("$limit", *_limit);
limitBuilder.doneFast();
}
BSONObjBuilder countBuilder(pipelineBuilder.subobjStart());
countBuilder.append("$count", "count");
countBuilder.doneFast();
pipelineBuilder.doneFast();
// Complete the command by appending the other options to count.
if (_collation) {
aggregationBuilder.append(kCollationField, *_collation);
}
if (_hint) {
aggregationBuilder.append(kHintField, *_hint);
}
if (!_comment.empty()) {
aggregationBuilder.append(kCommentField, _comment);
}
if (_maxTimeMS > 0) {
aggregationBuilder.append(kMaxTimeMSField, _maxTimeMS);
}
if (!_readConcern.isEmpty()) {
aggregationBuilder.append(kReadConcernField, _readConcern);
}
if (!_unwrappedReadPref.isEmpty()) {
aggregationBuilder.append(QueryRequest::kUnwrappedReadPrefField, _unwrappedReadPref);
}
// The 'cursor' option is always specified so that aggregation uses the cursor interface.
aggregationBuilder.append("cursor", BSONObj());
return aggregationBuilder.obj();
}
} // namespace mongo
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