Sending LanguageModel info to suggestions server

components/ntp_snippets/remote/ntp_snippets_fetcher.cc

Index: components/ntp_snippets/remote/ntp_snippets_fetcher.cc
diff --git a/components/ntp_snippets/remote/ntp_snippets_fetcher.cc b/components/ntp_snippets/remote/ntp_snippets_fetcher.cc
index 881bd8b76bad2af34697a6ead510fb043988de62..c69665d7ad232f0547837411c229d2929cac7f76 100644
--- a/components/ntp_snippets/remote/ntp_snippets_fetcher.cc
+++ b/components/ntp_snippets/remote/ntp_snippets_fetcher.cc
@@ -26,6 +26,7 @@
 #include "components/signin/core/browser/profile_oauth2_token_service.h"
 #include "components/signin/core/browser/signin_manager.h"
 #include "components/signin/core/browser/signin_manager_base.h"
+#include "components/translate/core/browser/language_model.h"
 #include "components/variations/net/variations_http_headers.h"
 #include "components/variations/variations_associated_data.h"
 #include "net/base/load_flags.h"
@@ -40,6 +41,7 @@ using net::URLFetcher;
 using net::URLRequestContextGetter;
 using net::HttpRequestHeaders;
 using net::URLRequestStatus;
+using translate::LanguageModel;
 
 namespace ntp_snippets {
 
@@ -166,6 +168,16 @@ std::string PosixLocaleFromBCP47Language(const std::string& language_code) {
   return locale;
 }
 
+std::string ISO639FromPosixLocale(const std::string& locale) {
+  char language[ULOC_LANG_CAPACITY];

[Bernhard Bauer, 2016/10/07 12:26:13]

This is not going to be zero-initialized, right? So if for some reason we can't
convert the language, are we going to construct a string from uninitialized
data?

[jkrcal, 2016/10/07 12:58:43]

Good point! This applies to the function above as well. I prefer to be more
explicit and use a regular if for error. Is it okay for you?

+  UErrorCode error = U_ZERO_ERROR;
+  uloc_getLanguage(locale.c_str(), language, ULOC_LANG_CAPACITY, &error);

[Bernhard Bauer, 2016/10/07 12:26:13]

#include "third_party/icu/source/common/unicode/uloc.h"?

[jkrcal, 2016/10/07 12:58:43]

It is already there, isn't it? ;)

+  DLOG_IF(WARNING, U_ZERO_ERROR != error)

[Bernhard Bauer, 2016/10/07 12:26:13]

Write the condition the natural way around? A modern compiler would complain
anyway if you accidentally used = instead of ==.

[jkrcal, 2016/10/07 12:58:43]

Done.

+      << "Error in translating locale string to a ISO639 language code: "
+      << error;
+  return language;
+}
+
 }  // namespace
 
 NTPSnippetsFetcher::FetchedCategory::FetchedCategory(Category c)
@@ -183,6 +195,7 @@ NTPSnippetsFetcher::NTPSnippetsFetcher(
     scoped_refptr<URLRequestContextGetter> url_request_context_getter,
     PrefService* pref_service,
     CategoryFactory* category_factory,
+    LanguageModel* language_model,
     const ParseJSONCallback& parse_json_callback,
     const std::string& api_key)
     : OAuth2TokenService::Consumer("ntp_snippets"),
@@ -191,6 +204,7 @@ NTPSnippetsFetcher::NTPSnippetsFetcher(
       waiting_for_refresh_token_(false),
       url_request_context_getter_(std::move(url_request_context_getter)),
       category_factory_(category_factory),
+      language_model_(language_model),
       parse_json_callback_(parse_json_callback),
       count_to_fetch_(0),
       fetch_url_(GetFetchEndpoint()),
@@ -274,6 +288,17 @@ void NTPSnippetsFetcher::FetchSnippetsFromHosts(
   }
 }
 
+NTPSnippetsFetcher::ContentLanguageInfo::ContentLanguageInfo()
+    : language_code(), frequency(0) {}
+
+void NTPSnippetsFetcher::ContentLanguageInfo::AppendToList(
+    base::ListValue* list) {
+  auto lang = base::MakeUnique<base::DictionaryValue>();
+  lang->SetString("language", language_code);
+  lang->SetDouble("frequency", frequency);
+  list->Append(std::move(lang));
+}
+
 NTPSnippetsFetcher::RequestParams::RequestParams()
     : fetch_api(),
       obfuscated_gaia_id(),
@@ -357,6 +382,16 @@ std::string NTPSnippetsFetcher::RequestParams::BuildRequest() {
       }
       request->Set("excludedSuggestionIds", std::move(excluded));
 
+      if (ui_language.frequency == 0 && other_top_language.frequency == 0)
+        break;
+
+      auto language_list = base::MakeUnique<base::ListValue>();
+      if (ui_language.frequency > 0)
+        ui_language.AppendToList(language_list.get());
+      if (other_top_language.frequency > 0)
+        other_top_language.AppendToList(language_list.get());
+      request->Set("top_languages", std::move(language_list));
+
       // TODO(sfiera): support authentication and personalization
       // TODO(sfiera): support count_to_fetch
       break;
@@ -409,18 +444,43 @@ bool NTPSnippetsFetcher::UsesAuthentication() const {
           personalization_ == Personalization::kBoth);
 }
 
+void NTPSnippetsFetcher::SetUpCommonFetchingParameters(
+    RequestParams* params) const {
+  params->fetch_api = fetch_api_;
+  params->host_restricts = hosts_;
+  params->user_locale = locale_;
+  params->excluded_ids = excluded_ids_;
+  params->count_to_fetch = count_to_fetch_;
+  params->interactive_request = interactive_request_;
+
+  // TODO(jkrcal): Add language model factory for iOS and add fakes to tests so
+  // that |language_model_| is never nullptr. Remove this check and add a DCHECK
+  // into the constructor.
+  if (!language_model_)
+    return;
+
+  params->ui_language.language_code = ISO639FromPosixLocale(locale_);
+  params->ui_language.frequency =
+      language_model_->GetLanguageFrequency(params->ui_language.language_code);
+
+  std::vector<LanguageModel::LanguageInfo> top_languages =
+      language_model_->GetTopLanguages();
+  for (const LanguageModel::LanguageInfo& info : top_languages) {
+    if (info.language_code != params->ui_language.language_code) {
+      params->other_top_language.language_code = info.language_code;
+      params->other_top_language.frequency = info.frequency;
+      break;
+    }
+  }
+}
+
 void NTPSnippetsFetcher::FetchSnippetsNonAuthenticated() {
   // When not providing OAuth token, we need to pass the Google API key.
   GURL url(base::StringPrintf(kSnippetsServerNonAuthorizedFormat,
                               fetch_url_.spec().c_str(), api_key_.c_str()));
 
   RequestParams params;
-  params.fetch_api = fetch_api_;
-  params.host_restricts = hosts_;
-  params.excluded_ids = excluded_ids_;
-  params.count_to_fetch = count_to_fetch_;
-  params.interactive_request = interactive_request_;
-  params.user_locale = locale_;
+  SetUpCommonFetchingParameters(&params);
   FetchSnippetsImpl(url, std::string(), params.BuildRequest());
 }
 
@@ -428,15 +488,10 @@ void NTPSnippetsFetcher::FetchSnippetsAuthenticated(
     const std::string& account_id,
     const std::string& oauth_access_token) {
   RequestParams params;
-  params.fetch_api = fetch_api_;
+  SetUpCommonFetchingParameters(&params);
   params.obfuscated_gaia_id = account_id;
   params.only_return_personalized_results =
       personalization_ == Personalization::kPersonal;
-  params.user_locale = locale_;
-  params.host_restricts = hosts_;
-  params.excluded_ids = excluded_ids_;
-  params.count_to_fetch = count_to_fetch_;
-  params.interactive_request = interactive_request_;
   // TODO(jkrcal, treib): Add unit-tests for authenticated fetches.
   FetchSnippetsImpl(fetch_url_,
                     base::StringPrintf(kAuthorizationRequestHeaderFormat,