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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.
*/
#pragma once
#include <boost/optional.hpp>
#include <string>
#include "mongo/db/catalog/collection_options.h"
#include "mongo/db/jsobj.h"
#include "mongo/db/namespace_string.h"
#include "mongo/db/operation_context.h"
#include "mongo/db/pipeline/legacy_runtime_constants_gen.h"
#include "mongo/db/query/tailable_mode.h"
namespace mongo {
class QueryMessage;
class Status;
template <typename T>
class StatusWith;
/**
* Parses the QueryMessage or find command received from the user and makes the various fields
* more easily accessible.
*/
class QueryRequest {
public:
// Find command field names.
static constexpr auto kFilterField = "filter";
static constexpr auto kProjectionField = "projection";
static constexpr auto kSortField = "sort";
static constexpr auto kHintField = "hint";
static constexpr auto kCollationField = "collation";
static constexpr auto kSkipField = "skip";
static constexpr auto kLimitField = "limit";
static constexpr auto kBatchSizeField = "batchSize";
static constexpr auto kNToReturnField = "ntoreturn";
static constexpr auto kSingleBatchField = "singleBatch";
static constexpr auto kMaxField = "max";
static constexpr auto kMinField = "min";
static constexpr auto kReturnKeyField = "returnKey";
static constexpr auto kShowRecordIdField = "showRecordId";
static constexpr auto kTailableField = "tailable";
static constexpr auto kOplogReplayField = "oplogReplay";
static constexpr auto kNoCursorTimeoutField = "noCursorTimeout";
static constexpr auto kAwaitDataField = "awaitData";
static constexpr auto kPartialResultsField = "allowPartialResults";
static constexpr auto kLegacyRuntimeConstantsField = "runtimeConstants";
static constexpr auto kLetField = "let";
static constexpr auto kTermField = "term";
static constexpr auto kOptionsField = "options";
static constexpr auto kReadOnceField = "readOnce";
static constexpr auto kAllowSpeculativeMajorityReadField = "allowSpeculativeMajorityRead";
static constexpr auto kRequestResumeTokenField = "$_requestResumeToken";
static constexpr auto kResumeAfterField = "$_resumeAfter";
static constexpr auto kUse44SortKeys = "_use44SortKeys";
static constexpr auto kMaxTimeMSOpOnlyField = "maxTimeMSOpOnly";
// Field names for sorting options.
static constexpr auto kNaturalSortField = "$natural";
static constexpr auto kFindCommandName = "find";
static constexpr auto kShardVersionField = "shardVersion";
explicit QueryRequest(NamespaceStringOrUUID nss);
/**
* Returns a non-OK status if any property of the QR has a bad value (e.g. a negative skip
* value) or if there is a bad combination of options (e.g. awaitData is illegal without
* tailable).
*/
Status validate() const;
/**
* Parses a find command object, 'cmdObj'. Caller must indicate whether or not this lite
* parsed query is an explained query or not via 'isExplain'. Accepts a NSS with which
* to initialize the QueryRequest if there is no UUID in cmdObj.
*
* Returns a heap allocated QueryRequest on success or an error if 'cmdObj' is not well
* formed.
*/
static StatusWith<std::unique_ptr<QueryRequest>> makeFromFindCommand(NamespaceString nss,
const BSONObj& cmdObj,
bool isExplain);
/**
* If _uuid exists for this QueryRequest, update the value of _nss.
*/
void refreshNSS(const NamespaceString& nss);
/**
* Converts this QR into a find command.
* The withUuid variants make a UUID-based find command instead of a namespace-based ones.
*/
BSONObj asFindCommand() const;
BSONObj asFindCommandWithUuid() const;
void asFindCommand(BSONObjBuilder* cmdBuilder) const;
void asFindCommandWithUuid(BSONObjBuilder* cmdBuilder) const;
/**
* Converts this QR into an aggregation using $match. If this QR has options that cannot be
* satisfied by aggregation, a non-OK status is returned and 'cmdBuilder' is not modified.
*/
StatusWith<BSONObj> asAggregationCommand() const;
/**
* Parses maxTimeMS from the BSONElement containing its value.
* The field name of the 'maxTimeMSElt' is used to determine what maximum value to enforce for
* the provided max time. 'maxTimeMSOpOnly' needs a slightly higher max value than regular
* 'maxTimeMS' to account for the case where a user provides the max possible value for
* 'maxTimeMS' to one server process (mongod or mongos), then that server process passes the max
* time on to another server as 'maxTimeMSOpOnly', but after adding a small amount to the max
* time to account for clock precision. This can push the 'maxTimeMSOpOnly' sent to the mongod
* over the max value allowed for users to provide. This is safe because 'maxTimeMSOpOnly' is
* only allowed to be provided for internal intra-cluster requests.
*/
static StatusWith<int> parseMaxTimeMS(BSONElement maxTimeMSElt);
/**
* Helper function to identify text search sort key
* Example: {a: {$meta: "textScore"}}
*/
static bool isTextScoreMeta(BSONElement elt);
// Read preference is attached to commands in "wrapped" form, e.g.
// { $query: { <cmd>: ... } , <kWrappedReadPrefField>: { ... } }
//
// However, mongos internally "unwraps" the read preference and adds it as a parameter to the
// command, e.g.
// { <cmd>: ... , <kUnwrappedReadPrefField>: { <kWrappedReadPrefField>: { ... } } }
static constexpr auto kWrappedReadPrefField = "$readPreference";
static constexpr auto kUnwrappedReadPrefField = "$queryOptions";
// Names of the maxTimeMS command and query option.
// Char arrays because they are used in static initialization.
static constexpr auto cmdOptionMaxTimeMS = "maxTimeMS";
static constexpr auto queryOptionMaxTimeMS = "$maxTimeMS";
// Names of the $meta projection values.
static constexpr auto metaGeoNearDistance = "geoNearDistance";
static constexpr auto metaGeoNearPoint = "geoNearPoint";
static constexpr auto metaRecordId = "recordId";
static constexpr auto metaSortKey = "sortKey";
static constexpr auto metaTextScore = "textScore";
// Allow using disk during the find command.
static constexpr auto kAllowDiskUseField = "allowDiskUse";
// A constant by which 'maxTimeMSOpOnly' values are allowed to exceed the max allowed value for
// 'maxTimeMS'. This is because mongod and mongos server processes add a small amount to the
// 'maxTimeMS' value they are given before passing it on as 'maxTimeMSOpOnly', to allow for
// clock precision.
static constexpr auto kMaxTimeMSOpOnlyMaxPadding = 100LL;
const NamespaceString& nss() const {
return _nss;
}
boost::optional<UUID> uuid() const {
return _uuid;
}
const BSONObj& getFilter() const {
return _filter;
}
void setFilter(BSONObj filter) {
_filter = filter.getOwned();
}
const BSONObj& getProj() const {
return _proj;
}
void setProj(BSONObj proj) {
_proj = proj.getOwned();
}
const BSONObj& getSort() const {
return _sort;
}
void setSort(BSONObj sort) {
_sort = sort.getOwned();
}
const BSONObj& getHint() const {
return _hint;
}
void setHint(BSONObj hint) {
_hint = hint.getOwned();
}
const BSONObj& getReadConcern() const {
if (_readConcern) {
return *_readConcern;
} else {
static const auto empty = BSONObj();
return empty;
}
}
void setReadConcern(BSONObj readConcern) {
_readConcern = readConcern.getOwned();
}
const BSONObj& getCollation() const {
return _collation;
}
void setCollation(BSONObj collation) {
_collation = collation.getOwned();
}
static constexpr auto kDefaultBatchSize = 101ll;
boost::optional<long long> getSkip() const {
return _skip;
}
void setSkip(boost::optional<long long> skip) {
_skip = skip;
}
boost::optional<long long> getLimit() const {
return _limit;
}
void setLimit(boost::optional<long long> limit) {
_limit = limit;
}
boost::optional<long long> getBatchSize() const {
return _batchSize;
}
void setBatchSize(boost::optional<long long> batchSize) {
_batchSize = batchSize;
}
boost::optional<long long> getNToReturn() const {
return _ntoreturn;
}
void setNToReturn(boost::optional<long long> ntoreturn) {
_ntoreturn = ntoreturn;
}
/**
* Returns batchSize or ntoreturn value if either is set. If neither is set,
* returns boost::none.
*/
boost::optional<long long> getEffectiveBatchSize() const;
bool wantMore() const {
return _wantMore;
}
void setWantMore(bool wantMore) {
_wantMore = wantMore;
}
bool allowDiskUse() const {
return _allowDiskUse;
}
void setAllowDiskUse(bool allowDiskUse) {
_allowDiskUse = allowDiskUse;
}
bool isExplain() const {
return _explain;
}
void setExplain(bool explain) {
_explain = explain;
}
const BSONObj& getUnwrappedReadPref() const {
return _unwrappedReadPref;
}
void setUnwrappedReadPref(BSONObj unwrappedReadPref) {
_unwrappedReadPref = unwrappedReadPref.getOwned();
}
int getMaxTimeMS() const {
return _maxTimeMS;
}
void setMaxTimeMS(int maxTimeMS) {
_maxTimeMS = maxTimeMS;
}
const BSONObj& getMin() const {
return _min;
}
void setMin(BSONObj min) {
_min = min.getOwned();
}
const BSONObj& getMax() const {
return _max;
}
void setMax(BSONObj max) {
_max = max.getOwned();
}
bool returnKey() const {
return _returnKey;
}
void setReturnKey(bool returnKey) {
_returnKey = returnKey;
}
bool showRecordId() const {
return _showRecordId;
}
void setShowRecordId(bool showRecordId) {
_showRecordId = showRecordId;
}
bool hasReadPref() const {
return _hasReadPref;
}
void setHasReadPref(bool hasReadPref) {
_hasReadPref = hasReadPref;
}
bool isTailable() const {
return _tailableMode == TailableModeEnum::kTailable ||
_tailableMode == TailableModeEnum::kTailableAndAwaitData;
}
bool isTailableAndAwaitData() const {
return _tailableMode == TailableModeEnum::kTailableAndAwaitData;
}
void setTailableMode(TailableModeEnum tailableMode) {
_tailableMode = tailableMode;
}
TailableModeEnum getTailableMode() const {
return _tailableMode;
}
void setLegacyRuntimeConstants(LegacyRuntimeConstants runtimeConstants) {
_legacyRuntimeConstants = std::move(runtimeConstants);
}
const boost::optional<LegacyRuntimeConstants>& getLegacyRuntimeConstants() const {
return _legacyRuntimeConstants;
}
void setLetParameters(BSONObj letParams) {
_letParameters = std::move(letParams);
}
const boost::optional<BSONObj>& getLetParameters() const {
return _letParameters;
}
bool isSlaveOk() const {
return _slaveOk;
}
void setSlaveOk(bool slaveOk) {
_slaveOk = slaveOk;
}
bool isNoCursorTimeout() const {
return _noCursorTimeout;
}
void setNoCursorTimeout(bool noCursorTimeout) {
_noCursorTimeout = noCursorTimeout;
}
bool isExhaust() const {
return _exhaust;
}
void setExhaust(bool exhaust) {
_exhaust = exhaust;
}
bool isAllowPartialResults() const {
return _allowPartialResults;
}
void setAllowPartialResults(bool allowPartialResults) {
_allowPartialResults = allowPartialResults;
}
boost::optional<long long> getReplicationTerm() const {
return _replicationTerm;
}
void setReplicationTerm(boost::optional<long long> replicationTerm) {
_replicationTerm = replicationTerm;
}
bool isReadOnce() const {
return _readOnce;
}
void setReadOnce(bool readOnce) {
_readOnce = readOnce;
}
void setAllowSpeculativeMajorityRead(bool allowSpeculativeMajorityRead) {
_allowSpeculativeMajorityRead = allowSpeculativeMajorityRead;
}
bool allowSpeculativeMajorityRead() const {
return _allowSpeculativeMajorityRead;
}
bool getRequestResumeToken() const {
return _requestResumeToken;
}
void setRequestResumeToken(bool requestResumeToken) {
_requestResumeToken = requestResumeToken;
}
const BSONObj& getResumeAfter() const {
return _resumeAfter;
}
void setResumeAfter(BSONObj resumeAfter) {
_resumeAfter = resumeAfter;
}
/**
* Return options as a bit vector.
*/
int getOptions() const;
//
// Old parsing code: SOON TO BE DEPRECATED.
//
/**
* Parse the provided QueryMessage and return a heap constructed QueryRequest, which
* represents it or an error.
*/
static StatusWith<std::unique_ptr<QueryRequest>> fromLegacyQueryMessage(const QueryMessage& qm);
/**
* Parse the provided legacy query object and parameters to construct a QueryRequest.
*/
static StatusWith<std::unique_ptr<QueryRequest>> fromLegacyQuery(NamespaceStringOrUUID nsOrUuid,
const BSONObj& queryObj,
const BSONObj& proj,
int ntoskip,
int ntoreturn,
int queryOptions);
private:
static StatusWith<std::unique_ptr<QueryRequest>> parseFromFindCommand(
std::unique_ptr<QueryRequest> qr, const BSONObj& cmdObj, bool isExplain);
Status init(int ntoskip,
int ntoreturn,
int queryOptions,
const BSONObj& queryObj,
const BSONObj& proj,
bool fromQueryMessage);
Status initFullQuery(const BSONObj& top);
/**
* Updates the projection object with a $meta projection for the showRecordId option.
*/
void addShowRecordIdMetaProj();
/**
* Initializes options based on the value of the 'options' bit vector.
*
* This contains flags such as tailable, exhaust, and noCursorTimeout.
*/
void initFromInt(int options);
/**
* Add the meta projection to this object if needed.
*/
void addMetaProjection();
/**
* Common code for UUID and namespace-based find commands.
*/
void asFindCommandInternal(BSONObjBuilder* cmdBuilder) const;
NamespaceString _nss;
OptionalCollectionUUID _uuid;
BSONObj _filter;
BSONObj _proj;
BSONObj _sort;
// The hint provided, if any. If the hint was by index key pattern, the value of '_hint' is
// the key pattern hinted. If the hint was by index name, the value of '_hint' is
// {$hint: <String>}, where <String> is the index name hinted.
BSONObj _hint;
// The read concern is parsed elsewhere.
boost::optional<BSONObj> _readConcern;
// The collation is parsed elsewhere.
BSONObj _collation;
// The unwrapped readPreference object, if one was given to us by the mongos command processor.
// This object will be empty when no readPreference is specified or if the request does not
// originate from mongos.
BSONObj _unwrappedReadPref;
// If true, each cursor response will include a 'postBatchResumeToken' field containing the
// RecordID of the last observed document.
bool _requestResumeToken = false;
// If non-empty, instructs the query to resume from the RecordId given by the object's $recordId
// field.
BSONObj _resumeAfter;
bool _wantMore = true;
// Must be either unset or positive. Negative skip is illegal and a skip of zero received from
// the client is interpreted as the absence of a skip value.
boost::optional<long long> _skip;
// Must be either unset or positive. Negative limit is illegal and a limit value of zero
// received from the client is interpreted as the absence of a limit value.
boost::optional<long long> _limit;
// Must be either unset or non-negative. Negative batchSize is illegal but batchSize of 0 is
// allowed.
boost::optional<long long> _batchSize;
bool _allowDiskUse = false;
// Set only when parsed from an OP_QUERY find message. The value is computed by driver or shell
// and is set to be a min of batchSize and limit provided by user. QR can have set either
// ntoreturn or batchSize / limit.
boost::optional<long long> _ntoreturn;
bool _explain = false;
// A user-specified maxTimeMS limit, or a value of '0' if not specified.
int _maxTimeMS = 0;
BSONObj _min;
BSONObj _max;
bool _returnKey = false;
bool _showRecordId = false;
bool _hasReadPref = false;
// Runtime constants which may be referenced by $expr, if present.
boost::optional<LegacyRuntimeConstants> _legacyRuntimeConstants;
// A document containing user-specified constants. For a find query, these are accessed only
// inside $expr.
boost::optional<BSONObj> _letParameters;
// Options that can be specified in the OP_QUERY 'flags' header.
TailableModeEnum _tailableMode = TailableModeEnum::kNormal;
bool _slaveOk = false;
bool _noCursorTimeout = false;
bool _exhaust = false;
bool _allowPartialResults = false;
bool _readOnce = false;
bool _allowSpeculativeMajorityRead = false;
boost::optional<long long> _replicationTerm;
};
} // namespace mongo
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