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
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
|
/**
* Copyright (C) 2016 MongoDB Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* 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
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* 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 GNU Affero General 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 <memory>
#include <vector>
#include "mongo/bson/bsonobj.h"
#include "mongo/db/namespace_string.h"
#include "mongo/db/pipeline/aggregation_request.h"
#include "mongo/db/pipeline/lite_parsed_document_source.h"
namespace mongo {
/**
* A semi-parsed version of a Pipeline, parsed just enough to determine information like what
* foreign collections are involved.
*/
class LiteParsedPipeline {
public:
/**
* Constructs a LiteParsedPipeline from the raw BSON stages given in 'request'.
*
* May throw a AssertionException if there is an invalid stage specification, although full
* validation happens later, during Pipeline construction.
*/
LiteParsedPipeline(const AggregationRequest& request) {
_stageSpecs.reserve(request.getPipeline().size());
for (auto&& rawStage : request.getPipeline()) {
_stageSpecs.push_back(LiteParsedDocumentSource::parse(request, rawStage));
}
}
/**
* Returns all foreign namespaces referenced by stages within this pipeline, if any.
*/
stdx::unordered_set<NamespaceString> getInvolvedNamespaces() const {
stdx::unordered_set<NamespaceString> involvedNamespaces;
for (auto&& spec : _stageSpecs) {
auto stagesInvolvedNamespaces = spec->getInvolvedNamespaces();
involvedNamespaces.insert(stagesInvolvedNamespaces.begin(),
stagesInvolvedNamespaces.end());
}
return involvedNamespaces;
}
/**
* Returns a list of the priviliges required for this pipeline.
*/
PrivilegeVector requiredPrivileges(bool isMongos) const {
PrivilegeVector requiredPrivileges;
for (auto&& spec : _stageSpecs) {
Privilege::addPrivilegesToPrivilegeVector(&requiredPrivileges,
spec->requiredPrivileges(isMongos));
}
return requiredPrivileges;
}
/**
* Returns true if the pipeline begins with a $collStats stage.
*/
bool startsWithCollStats() const {
return !_stageSpecs.empty() && _stageSpecs.front()->isCollStats();
}
/**
* Returns true if the pipeline has a $changeStream stage.
*/
bool hasChangeStream() const {
return std::any_of(_stageSpecs.begin(), _stageSpecs.end(), [](auto&& spec) {
return spec->isChangeStream();
});
}
/**
* Returns false if the pipeline has any stage which must be run locally on mongos.
*/
bool allowedToForwardFromMongos() const {
return std::all_of(_stageSpecs.cbegin(), _stageSpecs.cend(), [](const auto& spec) {
return spec->allowedToForwardFromMongos();
});
}
/**
* Returns false if the pipeline has any Document Source which requires rewriting via serialize.
*/
bool allowedToPassthroughFromMongos() const {
return std::all_of(_stageSpecs.cbegin(), _stageSpecs.cend(), [](const auto& spec) {
return spec->allowedToPassthroughFromMongos();
});
}
/**
* Returns false if at least one of the stages does not allow the involved namespace 'nss' to be
* sharded.
*/
bool allowShardedForeignCollection(NamespaceString nss) const {
return std::all_of(_stageSpecs.begin(), _stageSpecs.end(), [&nss](auto&& spec) {
return spec->allowShardedForeignCollection(nss);
});
}
/**
* Verifies that this pipeline is allowed to run with the specified read concern. This ensures
* that each stage is compatible, and throws a UserException if not.
*/
void assertSupportsReadConcern(OperationContext* opCtx,
boost::optional<ExplainOptions::Verbosity> explain) const {
auto readConcern = repl::ReadConcernArgs::get(opCtx);
uassert(ErrorCodes::InvalidOptions,
str::stream() << "Explain for the aggregate command cannot run with a readConcern "
<< "other than 'local', or in a multi-document transaction. Current "
<< "readConcern: "
<< readConcern.toString(),
!explain || readConcern.getLevel() == repl::ReadConcernLevel::kLocalReadConcern);
for (auto&& spec : _stageSpecs) {
spec->assertSupportsReadConcern(readConcern);
}
}
private:
std::vector<std::unique_ptr<LiteParsedDocumentSource>> _stageSpecs;
};
} // namespace mongo
|
