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
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
|
/**
* 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/db/update_index_data.h"
#include "mongo/bson/util/builder.h"
namespace mongo {
namespace {
enum class NumericPathComponentResult {
kNumericOrDollar,
kConsecutiveNumbers,
kNonNumericOrDollar
};
NumericPathComponentResult checkNumericOrDollarPathComponent(const FieldRef& path,
size_t pathIdx,
const StringData& pathComponent) {
if (pathComponent == "$"_sd) {
return NumericPathComponentResult::kNumericOrDollar;
}
if (FieldRef::isNumericPathComponentLenient(pathComponent)) {
// Peek ahead to see if the next component is also all digits. This implies that the
// update is attempting to create a numeric field name which would violate the
// "ambiguous field name in array" constraint for multi-key indexes. Break early in this
// case and conservatively return that this path affects the prefix of the consecutive
// numerical path components. For instance, an input such as 'a.0.1.b.c' would return
// the canonical index path of 'a'.
if ((pathIdx + 1) < path.numParts() &&
FieldRef::isNumericPathComponentLenient(path.getPart(pathIdx + 1))) {
return NumericPathComponentResult::kConsecutiveNumbers;
}
return NumericPathComponentResult::kNumericOrDollar;
}
return NumericPathComponentResult::kNonNumericOrDollar;
}
/**
* Checks whether a given Document path overlaps with an indexed path
*/
bool pathOverlaps(const FieldRef& path, const FieldRef& indexedPath) {
size_t pathIdx = 0;
size_t indexedPathIdx = 0;
while (pathIdx < path.numParts() && indexedPathIdx < indexedPath.numParts()) {
auto pathComponent = path.getPart(pathIdx);
// The first part of the path must always be a valid field name, since it's not possible to
// store a top-level array or '$' field name in a document.
if (pathIdx > 0) {
NumericPathComponentResult res =
checkNumericOrDollarPathComponent(path, pathIdx, pathComponent);
if (res == NumericPathComponentResult::kNumericOrDollar) {
++pathIdx;
continue;
}
if (res == NumericPathComponentResult::kConsecutiveNumbers) {
// This case implies that the update is attempting to create a numeric field name
// which would violate the "ambiguous field name in array" constraint for multi-key
// indexes. Break early in this case and conservatively return that this path
// affects the prefix of the consecutive numerical path components. For instance, an
// input path such as 'a.0.1.b.c' would match indexed path of 'a.d'.
return true;
}
}
StringData indexedPathComponent = indexedPath.getPart(indexedPathIdx);
if (pathComponent != indexedPathComponent) {
return false;
}
++pathIdx;
++indexedPathIdx;
}
return true;
}
} // namespace
UpdateIndexData::UpdateIndexData() : _allPathsIndexed(false) {}
void UpdateIndexData::addPath(const FieldRef& path) {
_canonicalPaths.insert(getCanonicalIndexField(path));
}
void UpdateIndexData::addPathComponent(StringData pathComponent) {
_pathComponents.insert(pathComponent.toString());
}
void UpdateIndexData::allPathsIndexed() {
_allPathsIndexed = true;
}
void UpdateIndexData::clear() {
_canonicalPaths.clear();
_pathComponents.clear();
_allPathsIndexed = false;
}
bool UpdateIndexData::mightBeIndexed(const FieldRef& path) const {
if (_allPathsIndexed) {
return true;
}
for (const auto& indexedPath : _canonicalPaths) {
if (pathOverlaps(path, indexedPath)) {
return true;
}
}
for (const auto& pathComponent : _pathComponents) {
for (size_t partIdx = 0; partIdx < path.numParts(); ++partIdx) {
if (pathComponent == path.getPart(partIdx)) {
return true;
}
}
}
return false;
}
bool UpdateIndexData::_startsWith(const FieldRef& a, const FieldRef& b) const {
return (a == b) || (b.isPrefixOf(a));
}
FieldRef UpdateIndexData::getCanonicalIndexField(const FieldRef& path) {
if (path.numParts() <= 1)
return path;
// The first part of the path must always be a valid field name, since it's not possible to
// store a top-level array or '$' field name in a document.
FieldRef buf(path.getPart(0));
for (size_t i = 1; i < path.numParts(); ++i) {
auto pathComponent = path.getPart(i);
NumericPathComponentResult res = checkNumericOrDollarPathComponent(path, i, pathComponent);
if (res == NumericPathComponentResult::kNumericOrDollar) {
continue;
}
if (res == NumericPathComponentResult::kConsecutiveNumbers) {
break;
}
buf.appendPart(pathComponent);
}
return buf;
}
bool UpdateIndexData::isComponentPartOfCanonicalizedIndexPath(StringData pathComponent) {
return pathComponent != "$"_sd && !FieldRef::isNumericPathComponentLenient(pathComponent);
}
} // namespace mongo
|
