1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
|
/**
* 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/intrusive_ptr.hpp>
#include <boost/optional/optional.hpp>
#include "mongo/db/catalog/collection.h"
#include "mongo/db/exec/plan_stage.h"
#include "mongo/db/exec/plan_stats.h"
#include "mongo/db/pipeline/pipeline.h"
#include "mongo/db/query/plan_summary_stats.h"
#include "mongo/db/record_id.h"
#include "mongo/util/assert_util.h"
namespace mongo {
/**
* Stage for pulling results out from an aggregation pipeline.
*/
class PipelineProxyStage final : public PlanStage {
public:
PipelineProxyStage(OperationContext* opCtx,
std::unique_ptr<Pipeline, PipelineDeleter> pipeline,
WorkingSet* ws);
PlanStage::StageState doWork(WorkingSetID* out) final;
bool isEOF() final;
//
// Manage our OperationContext.
//
void doDetachFromOperationContext() final;
void doReattachToOperationContext() final;
// Returns empty PlanStageStats object
std::unique_ptr<PlanStageStats> getStats() final;
// Not used.
SpecificStats* getSpecificStats() const final {
MONGO_UNREACHABLE;
}
/**
* Pass through the last oplog timestamp from the proxied pipeline.
*/
Timestamp getLatestOplogTimestamp() const;
std::string getPlanSummaryStr() const;
void getPlanSummaryStats(PlanSummaryStats* statsOut) const;
StageType stageType() const final {
return STAGE_PIPELINE_PROXY;
}
/**
* Writes the pipelineProxyStage's operators to a std::vector<Value>, providing the level of
* detail specified by 'verbosity'.
*/
std::vector<Value> writeExplainOps(ExplainOptions::Verbosity verbosity) const;
static const char* kStageType;
protected:
void doDispose() final;
private:
boost::optional<BSONObj> getNextBson();
// Things in the _stash should be returned before pulling items from _pipeline.
std::unique_ptr<Pipeline, PipelineDeleter> _pipeline;
std::vector<BSONObj> _stash;
const bool _includeMetaData;
// Not owned by us.
WorkingSet* _ws;
};
} // namespace mongo
|
