[Suggestions Service] Add support for expiring the SuggestionsStore

components/suggestions/suggestions_store.cc

 // Copyright 2014 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/suggestions/suggestions_store.h"
 
 #include <string>
 
 #include "base/base64.h"
 #include "base/prefs/pref_service.h"
+#include "base/time/time.h"
 #include "components/pref_registry/pref_registry_syncable.h"
 #include "components/suggestions/suggestions_pref_names.h"
 
 namespace suggestions {
 
 SuggestionsStore::SuggestionsStore(PrefService* profile_prefs)
     : pref_service_(profile_prefs) {
   DCHECK(profile_prefs);
 }
 
@@ skipping 12 matching lines @@
   // If the decode process fails, assume the pref value is corrupt and clear it.
   std::string suggestions_data;
   if (!base::Base64Decode(base64_suggestions_data, &suggestions_data) ||
       !suggestions->ParseFromString(suggestions_data)) {
     VLOG(1) << "Suggestions data in profile pref is corrupt, clearing it.";
     suggestions->Clear();
     ClearSuggestions();
     return false;
   }
 
+  // Filter expired suggestions and update the stored suggestions if at least
+  // one was filtered. Return false if all suggestions are filtered.
+  int unfiltered_size = suggestions->suggestions_size();
+  FilterExpiredSuggestions(suggestions);
+  if (suggestions->suggestions_size() != unfiltered_size) {
+    if (!suggestions->suggestions_size()) {
+      suggestions->Clear();
+      ClearSuggestions();
+      return false;
+    } else {
+      StoreSuggestions(*suggestions);
+    }
+  }
+
   return true;
 }
 
+void SuggestionsStore::FilterExpiredSuggestions(
+    SuggestionsProfile* suggestions) {
+  SuggestionsProfile filtered_suggestions;
+  int64 now_usec = (base::Time::NowFromSystemTime() - base::Time::UnixEpoch())
+      .ToInternalValue();
+
+  for (int i = 0; i < suggestions->suggestions_size(); ++i) {
+    ChromeSuggestion* suggestion = suggestions->mutable_suggestions(i);
+    if (!suggestion->has_expiry_ts() || suggestion->expiry_ts() > now_usec) {
+      filtered_suggestions.add_suggestions()->Swap(suggestion);
+    }
+  }
+  suggestions->Swap(&filtered_suggestions);
+}
+
 bool SuggestionsStore::StoreSuggestions(const SuggestionsProfile& suggestions) {
   std::string suggestions_data;
   if (!suggestions.SerializeToString(&suggestions_data)) return false;
 
   std::string base64_suggestions_data;
   base::Base64Encode(suggestions_data, &base64_suggestions_data);
 
   pref_service_->SetString(prefs::kSuggestionsData, base64_suggestions_data);
   return true;
 }
 
 void SuggestionsStore::ClearSuggestions() {
   pref_service_->ClearPref(prefs::kSuggestionsData);
 }
 
 // static
 void SuggestionsStore::RegisterProfilePrefs(
     user_prefs::PrefRegistrySyncable* registry) {
   registry->RegisterStringPref(
       prefs::kSuggestionsData, std::string(),
       user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 }
 
 }  // namespace suggestions