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
|
/**
* 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 <vector>
#include "mongo/db/matcher/expression.h"
#include "mongo/db/matcher/expression_tree.h"
#include "mongo/db/matcher/rewrite_expr.h"
#include "mongo/db/pipeline/expression.h"
#include "mongo/db/pipeline/expression_context.h"
#include "mongo/db/pipeline/expression_walker.h"
#include "mongo/util/assert_util.h"
namespace mongo {
/**
* MatchExpression for the top-level $expr keyword. Take an expression as an argument, evaluates and
* coerces to boolean form which determines whether a document is a match.
*/
class ExprMatchExpression final : public MatchExpression {
public:
ExprMatchExpression(BSONElement elem,
const boost::intrusive_ptr<ExpressionContext>& expCtx,
clonable_ptr<ErrorAnnotation> annotation = nullptr);
ExprMatchExpression(boost::intrusive_ptr<Expression> expr,
const boost::intrusive_ptr<ExpressionContext>& expCtx,
clonable_ptr<ErrorAnnotation> annotation = nullptr);
bool matchesSingleElement(const BSONElement& e, MatchDetails* details = nullptr) const final {
MONGO_UNREACHABLE;
}
bool matches(const MatchableDocument* doc, MatchDetails* details = nullptr) const final;
/**
* Evaluates the aggregation expression of this match expression on document 'doc' and returns
* the result.
*/
Value evaluateExpression(const MatchableDocument* doc) const;
std::unique_ptr<MatchExpression> shallowClone() const final;
void debugString(StringBuilder& debug, int indentationLevel = 0) const final {
_debugAddSpace(debug, indentationLevel);
debug << "$expr " << _expression->serialize(false).toString();
}
void serialize(BSONObjBuilder* out, bool includePath) const final;
bool isTriviallyTrue() const final;
bool equivalent(const MatchExpression* other) const final;
MatchCategory getCategory() const final {
return MatchCategory::kOther;
}
size_t numChildren() const final {
return 0;
}
MatchExpression* getChild(size_t i) const final {
MONGO_UNREACHABLE_TASSERT(6400207);
}
void resetChild(size_t, MatchExpression*) {
MONGO_UNREACHABLE;
};
std::vector<std::unique_ptr<MatchExpression>>* getChildVector() final {
return nullptr;
}
boost::intrusive_ptr<ExpressionContext> getExpressionContext() const {
return _expCtx;
}
boost::intrusive_ptr<Expression> getExpression() const {
return _expression;
}
/**
* Use if the caller needs to modify the expression held by this $expr.
*/
boost::intrusive_ptr<Expression>& getExpressionRef() {
return _expression;
}
void acceptVisitor(MatchExpressionMutableVisitor* visitor) final {
visitor->visit(this);
}
void acceptVisitor(MatchExpressionConstVisitor* visitor) const final {
visitor->visit(this);
}
/**
* Finds an applicable rename from 'renameList' (if one exists) and applies it to the
* expression. Each pair in 'renameList' specifies a path prefix that should be renamed (as the
* first element) and the path components that should replace the renamed prefix (as the second
* element).
*/
void applyRename(const StringMap<std::string>& renameList) {
SubstituteFieldPathWalker substituteWalker(renameList);
expression_walker::walk<Expression>(_expression.get(), &substituteWalker);
}
private:
ExpressionOptimizerFunc getOptimizer() const final;
void _doSetCollator(const CollatorInterface* collator) final;
boost::intrusive_ptr<ExpressionContext> _expCtx;
boost::intrusive_ptr<Expression> _expression;
boost::optional<RewriteExpr::RewriteResult> _rewriteResult;
};
} // namespace mongo
|