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
|
// Copyright 2021 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/feed/content/renderer/rss_link_reader.h"
#include <string>
#include "base/metrics/histogram_functions.h"
#include "base/strings/string_util.h"
#include "base/time/time.h"
#include "components/feed/mojom/rss_link_reader.mojom.h"
#include "content/public/renderer/render_frame.h"
#include "services/service_manager/public/cpp/binder_registry.h"
#include "third_party/blink/public/platform/web_url.h"
#include "third_party/blink/public/web/web_document.h"
#include "third_party/blink/public/web/web_element.h"
#include "third_party/blink/public/web/web_element_collection.h"
#include "third_party/blink/public/web/web_local_frame.h"
namespace feed {
namespace {
// Maximum number of RSS URLs to read.
constexpr int kMaxRssUrls = 50;
// Returns the RSS URL embedded in `link_element`, or any empty GURL if no RSS
// url is contained. This code is based on this internal implementation:
// http://shortn/_PIHj2svUjF
GURL GetRssUrlFromLinkElement(const blink::WebElement& link_element) {
if (!(link_element.HasAttribute("type") && link_element.HasAttribute("rel") &&
link_element.HasAttribute("href"))) {
return GURL();
}
blink::WebString web_type = link_element.GetAttribute("type");
blink::WebString web_rel = link_element.GetAttribute("rel");
if (!web_type.ContainsOnlyASCII() || !web_rel.ContainsOnlyASCII())
return GURL();
std::string type = web_type.Ascii();
if (!(base::LowerCaseEqualsASCII(type, "application/rss+xml") ||
base::LowerCaseEqualsASCII(type, "application/rss+atom") ||
base::LowerCaseEqualsASCII(type, "application/atom+xml"))) {
return GURL();
}
std::string rel = web_rel.Ascii();
if (!(base::LowerCaseEqualsASCII(rel, "alternate") ||
base::LowerCaseEqualsASCII(rel, "service.feed"))) {
return GURL();
}
blink::WebURL url =
link_element.GetDocument().CompleteURL(link_element.GetAttribute("href"));
return url.IsValid() ? GURL(url) : GURL();
}
void AddRssLinksFromElement(const blink::WebElement& element,
std::vector<GURL>* rss_urls) {
if (element.IsNull())
return;
blink::WebElementCollection link_iter =
element.GetElementsByHTMLTagName("link");
if (link_iter.IsNull())
return;
for (blink::WebElement link = link_iter.FirstItem();
!link.IsNull() && rss_urls->size() < kMaxRssUrls;
link = link_iter.NextItem()) {
GURL url = GetRssUrlFromLinkElement(link);
if (url.is_valid())
rss_urls->push_back(url);
}
}
std::vector<GURL> GetRssLinksFromDocument(blink::WebDocument document) {
std::vector<GURL> rss_urls;
if (document.IsNull())
return rss_urls;
AddRssLinksFromElement(document.Head(), &rss_urls);
// If head contained no RSS feed links, fallback to scanning the body.
if (rss_urls.empty())
AddRssLinksFromElement(document.Body(), &rss_urls);
return rss_urls;
}
} // namespace
RssLinkReader::RssLinkReader(content::RenderFrame* render_frame,
service_manager::BinderRegistry* registry)
: content::RenderFrameObserver(render_frame) {
// Being a RenderFrameObserver, this object is scoped to the RenderFrame.
// Unretained is safe here because `registry` is also scoped to the
// RenderFrame.
registry->AddInterface(base::BindRepeating(&RssLinkReader::BindReceiver,
base::Unretained(this)));
}
RssLinkReader::~RssLinkReader() = default;
void RssLinkReader::GetRssLinks(GetRssLinksCallback callback) {
base::TimeTicks start_time = base::TimeTicks::Now();
blink::WebDocument document = render_frame()->GetWebFrame()->GetDocument();
std::move(callback).Run(
mojom::RssLinks::New(document.Url(), GetRssLinksFromDocument(document)));
base::UmaHistogramMicrosecondsTimes(
"ContentSuggestions.Feed.WebFeed.GetRssLinksRendererTime",
base::TimeTicks::Now() - start_time);
}
void RssLinkReader::OnDestruct() {
delete this;
}
void RssLinkReader::BindReceiver(
mojo::PendingReceiver<mojom::RssLinkReader> receiver) {
receiver_.reset();
receiver_.Bind(std::move(receiver));
}
} // namespace feed
|
