[NTP Snippets] Limit the number of snippets to 10

components/ntp_snippets/ntp_snippets_fetcher.cc

 // Copyright 2016 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/ntp_snippets/ntp_snippets_fetcher.h"
 
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/path_service.h"
 #include "base/strings/string_number_conversions.h"
@@ skipping 38 matching lines @@
     "        \"type\": \"METADATA\","
     "        \"value\": \"SNIPPET\""
     "      },"
     "      \"content_restricts\": {"
     "        \"type\": \"METADATA\","
     "        \"value\": \"THUMBNAIL\""
     "      }"
     "%s"
     "    },"
     "    \"global_scoring_params\": {"
-    "      \"num_to_return\": 10"
+    "      \"num_to_return\": %i"
     "    }"
     "  }"
     "}";
 
 const char kHostRestrictFormat[] =
     "      ,\"content_selectors\": {"
     "        \"type\": \"HOST_RESTRICT\","
     "        \"value\": \"%s\""
     "      }";
 
 }  // namespace
 
 NTPSnippetsFetcher::NTPSnippetsFetcher(
     scoped_refptr<base::SequencedTaskRunner> file_task_runner,
     scoped_refptr<URLRequestContextGetter> url_request_context_getter,
     bool is_stable_channel)
     : file_task_runner_(file_task_runner),
       url_request_context_getter_(url_request_context_getter),
       is_stable_channel_(is_stable_channel) {}
 
-NTPSnippetsFetcher::~NTPSnippetsFetcher() {
-}
+NTPSnippetsFetcher::~NTPSnippetsFetcher() {}
 
 scoped_ptr<NTPSnippetsFetcher::SnippetsAvailableCallbackList::Subscription>
 NTPSnippetsFetcher::AddCallback(const SnippetsAvailableCallback& callback) {
   return callback_list_.Add(callback);
 }
 
-void NTPSnippetsFetcher::FetchSnippets(const std::set<std::string>& hosts) {
+void NTPSnippetsFetcher::FetchSnippets(const std::set<std::string>& hosts,
+                                       int count) {
   // TODO(treib): What to do if there's already a pending request?
   const std::string& key = is_stable_channel_
                                ? google_apis::GetAPIKey()
                                : google_apis::GetNonStableAPIKey();
   std::string url =
       base::StringPrintf(kContentSnippetsServerFormat, key.c_str());
   url_fetcher_ = URLFetcher::Create(GURL(url), URLFetcher::POST, this);
   url_fetcher_->SetRequestContext(url_request_context_getter_.get());
   url_fetcher_->SetLoadFlags(net::LOAD_DO_NOT_SEND_COOKIES |
                              net::LOAD_DO_NOT_SAVE_COOKIES);
   HttpRequestHeaders headers;
   headers.SetHeader("Content-Type", "application/json; charset=UTF-8");
   url_fetcher_->SetExtraRequestHeaders(headers.ToString());
   std::string host_restricts;
   for (const std::string& host : hosts)
     host_restricts += base::StringPrintf(kHostRestrictFormat, host.c_str());
   url_fetcher_->SetUploadData("application/json",
                               base::StringPrintf(kRequestParameterFormat,
-                                                 host_restricts.c_str()));
+                                                 host_restricts.c_str(),
+                                                 count));
 
   // Fetchers are sometimes cancelled because a network change was detected.
   url_fetcher_->SetAutomaticallyRetryOnNetworkChanges(3);
   // Try to make fetching the files bit more robust even with poor connection.
   url_fetcher_->SetMaxRetriesOn5xx(3);
   url_fetcher_->Start();
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // URLFetcherDelegate overrides
@@ skipping 17 matching lines @@
 
   } else {
     bool stores_result_to_string = source->GetResponseAsString(&response);
     DCHECK(stores_result_to_string);
   }
 
   callback_list_.Notify(response, message);
 }
 
 }  // namespace ntp_snippets