components/search_provider_logos/google_logo_api.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "components/search_provider_logos/google_logo_api.h"
   6
   7 #include "base/base64.h"
   8 #include "base/json/json_reader.h"
   9 #include "base/memory/ref_counted_memory.h"
  10 #include "base/strings/string_util.h"
  11 #include "base/values.h"
  12 #include "net/base/url_util.h"
  13
  14 namespace search_provider_logos {
  15
  16 namespace {
  17 const char kResponsePreamble[] = ")]}'";
  18 }
  19
  20 GURL GoogleAppendFingerprintToLogoURL(const GURL& logo_url,
  21                                       const std::string& fingerprint) {
  22   return net::AppendQueryParameter(logo_url, "async", "es_dfp:" + fingerprint);
  23 }
  24
  25 scoped_ptr<EncodedLogo> GoogleParseLogoResponse(
  26     const scoped_ptr<std::string>& response,
  27     base::Time response_time) {
  28   // Google doodles are sent as JSON with a prefix. Example:
  29   //   )]}' {"update":{"logo":{
  30   //     "data": "/9j/4QAYRXhpZgAASUkqAAgAAAAAAAAAAAAAAP/...",
  31   //     "mime_type": "image/png",
  32   //     "fingerprint": "db063e32",
  33   //     "target": "http://www.google.com.au/search?q=Wilbur+Christiansen",
  34   //     "alt": "Wilbur Christiansen's Birthday"
  35   //     "time_to_live": 1389304799
  36   //   }}}
  37
  38   // The response may start with )]}'. Ignore this.
  39   base::StringPiece response_sp(*response);
  40   if (response_sp.starts_with(kResponsePreamble))
  41     response_sp.remove_prefix(strlen(kResponsePreamble));
  42
  43   scoped_ptr<base::Value> value(base::JSONReader::Read(response_sp));
  44   if (!value.get())
  45     return scoped_ptr<EncodedLogo>();
  46
  47   // The important data lives inside several nested dictionaries:
  48   // {"update": {"logo": { "mime_type": ..., etc } } }
  49   const base::DictionaryValue* outer_dict;
  50   if (!value->GetAsDictionary(&outer_dict))
  51     return scoped_ptr<EncodedLogo>();
  52   const base::DictionaryValue* update_dict;
  53   if (!outer_dict->GetDictionary("update", &update_dict))
  54     return scoped_ptr<EncodedLogo>();
  55   const base::DictionaryValue* logo_dict;
  56   if (!update_dict->GetDictionary("logo", &logo_dict))
  57     return scoped_ptr<EncodedLogo>();
  58
  59   scoped_ptr<EncodedLogo> logo(new EncodedLogo());
  60
  61   std::string encoded_image_base64;
  62   if (logo_dict->GetString("data", &encoded_image_base64)) {
  63     // Data is optional, since we may be revalidating a cached logo.
  64     base::RefCountedString* encoded_image_string = new base::RefCountedString();
  65     if (!base::Base64Decode(encoded_image_base64,
  66                             &encoded_image_string->data()))
  67       return scoped_ptr<EncodedLogo>();
  68     logo->encoded_image = encoded_image_string;
  69     if (!logo_dict->GetString("mime_type", &logo->metadata.mime_type))
  70       return scoped_ptr<EncodedLogo>();
  71   }
  72
  73   // Don't check return values since these fields are optional.
  74   logo_dict->GetString("target", &logo->metadata.on_click_url);
  75   logo_dict->GetString("fingerprint", &logo->metadata.fingerprint);
  76   logo_dict->GetString("alt", &logo->metadata.alt_text);
  77
  78   base::TimeDelta time_to_live;
  79   int time_to_live_ms;
  80   if (logo_dict->GetInteger("time_to_live", &time_to_live_ms)) {
  81     time_to_live = base::TimeDelta::FromMilliseconds(
  82         std::min(static_cast<int64>(time_to_live_ms), kMaxTimeToLiveMS));
  83     logo->metadata.can_show_after_expiration = false;
  84   } else {
  85     time_to_live = base::TimeDelta::FromMilliseconds(kMaxTimeToLiveMS);
  86     logo->metadata.can_show_after_expiration = true;
  87   }
  88   logo->metadata.expiration_time = response_time + time_to_live;
  89
  90   return logo.Pass();
  91 }
  92
  93 }  // namespace search_provider_logos