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 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "components/dom_distiller/core/page_features.h"
#include <string>
#include "base/json/json_reader.h"
#include "third_party/re2/re2/re2.h"
namespace dom_distiller {
/* This code needs to derive features in the same way and order in which they
* are derived when training the model. Parts of that code are reproduced in the
* comments below.
*/
namespace {
std::string GetLastSegment(const std::string& path) {
// return re.search('[^/]*\/?$', path).group(0)
if (path.size() == 0)
return "";
size_t start = path.rfind("/", path.size() - 1);
return start == std::string::npos ? "" : path.substr(start + 1);
}
int CountMatches(const std::string& s, const std::string& p) {
// return len(re.findall(p, s))
re2::StringPiece sp(s);
re2::RE2 regexp(p);
int count = 0;
while (re2::RE2::FindAndConsume(&sp, regexp))
count++;
return count;
}
int GetWordCount(const std::string& s) {
return CountMatches(s, "\\w+");
}
bool Contains(const std::string& n, const std::string& h) {
return h.find(n) != std::string::npos;
}
bool EndsWith(const std::string& t, const std::string& s) {
return s.size() >= t.size() &&
s.compare(s.size() - t.size(), std::string::npos, t) == 0;
}
} // namespace
int kDerivedFeaturesCount = 29;
std::vector<double> CalculateDerivedFeatures(bool isOGArticle,
const GURL& url,
double numElements,
double numAnchors,
double numForms,
const std::string& innerText,
const std::string& textContent,
const std::string& innerHTML) {
// In the training pipeline, the strings are explicitly encoded in utf-8 (as
// they are here).
const std::string& path = url.path();
int innerTextWords = GetWordCount(innerText);
int textContentWords = GetWordCount(textContent);
int innerHTMLWords = GetWordCount(innerHTML);
std::vector<double> features;
// 'opengraph', opengraph,
features.push_back(isOGArticle);
// 'forum', 'forum' in path,
features.push_back(Contains("forum", path));
// 'index', 'index' in path,
features.push_back(Contains("index", path));
// 'view', 'view' in path,
features.push_back(Contains("view", path));
// 'asp', '.asp' in path,
features.push_back(Contains(".asp", path));
// 'phpbb', 'phpbb' in path,
features.push_back(Contains("phpbb", path));
// 'php', path.endswith('.php'),
features.push_back(EndsWith(".php", path));
// 'pathlength', len(path),
features.push_back(path.size());
// 'domain', len(path) < 2,
features.push_back(path.size() < 2);
// 'pathcomponents', CountMatches(path, r'\/.'),
features.push_back(CountMatches(path, "\\/."));
// 'slugdetector', CountMatches(path, r'[^\w/]'),
features.push_back(CountMatches(path, "[^\\w/]"));
// 'pathnumbers', CountMatches(path, r'\d+'),
features.push_back(CountMatches(path, "\\d+"));
// 'lastSegmentLength', len(GetLastSegment(path)),
features.push_back(GetLastSegment(path).size());
// 'formcount', numForms,
features.push_back(numForms);
// 'anchorcount', numAnchors,
features.push_back(numAnchors);
// 'elementcount', numElements,
features.push_back(numElements);
// 'anchorratio', float(numAnchors) / max(1, numElements),
features.push_back(double(numAnchors) / std::max<double>(1, numElements));
// 'innertextlength', len(innerText),
features.push_back(innerText.size());
// 'textcontentlength', len(textContent),
features.push_back(textContent.size());
// 'innerhtmllength', len(innerHTML),
features.push_back(innerHTML.size());
// 'innertextlengthratio', float(len(innerText)) / max(1, len(innerHTML)),
features.push_back(double(innerText.size()) /
std::max<double>(1.0, innerHTML.size()));
// 'textcontentlengthratio', float(len(textContent)) / max(1, len(innerHTML)),
features.push_back(double(textContent.size()) /
std::max<double>(1.0, innerHTML.size()));
// 'innertexttextcontentlengthratio',
// float(len(innerText)) / max(1, len(textContent)),
features.push_back(double(innerText.size()) /
std::max<double>(1.0, textContent.size()));
// 'innertextwordcount', innerTextWords,
features.push_back(innerTextWords);
// 'textcontentwordcount', textContentWords,
features.push_back(textContentWords);
// 'innerhtmlwordcount', innerHTMLWords,
features.push_back(innerHTMLWords);
// 'innertextwordcountratio', float(innerTextWords) / max(1, innerHTMLWords),
features.push_back(double(innerTextWords) /
std::max<int>(1.0, innerHTMLWords));
// 'textcontentwordcountratio',
// float(textContentWords) / max(1, innerHTMLWords),
features.push_back(double(textContentWords) /
std::max<int>(1.0, innerHTMLWords));
// 'innertexttextcontentwordcountratio',
// float(innerTextWords) / max(1, textContentWords),
features.push_back(double(innerTextWords) /
std::max<int>(1.0, textContentWords));
return features;
}
std::vector<double> CalculateDerivedFeaturesFromJSON(
const base::Value* stringified_json) {
std::string stringified;
if (!stringified_json->GetAsString(&stringified)) {
return std::vector<double>();
}
scoped_ptr<base::Value> json = base::JSONReader::Read(stringified);
if (!json) {
return std::vector<double>();
}
const base::DictionaryValue* dict;
if (!json->GetAsDictionary(&dict)) {
return std::vector<double>();
}
bool isOGArticle = false;
std::string url, innerText, textContent, innerHTML;
double numElements = 0.0, numAnchors = 0.0, numForms = 0.0;
if (!(dict->GetBoolean("opengraph", &isOGArticle) &&
dict->GetString("url", &url) &&
dict->GetDouble("numElements", &numElements) &&
dict->GetDouble("numAnchors", &numAnchors) &&
dict->GetDouble("numForms", &numForms) &&
dict->GetString("innerText", &innerText) &&
dict->GetString("textContent", &textContent) &&
dict->GetString("innerHTML", &innerHTML))) {
return std::vector<double>();
}
GURL parsed_url(url);
if (!parsed_url.is_valid()) {
return std::vector<double>();
}
return CalculateDerivedFeatures(isOGArticle, parsed_url, numElements,
numAnchors, numForms, innerText, textContent,
innerHTML);
}
} // namespace dom_distiller
|
