Send the list of used and unused resources for precache

components/precache/core/precache_referrer_host_table.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/precache/core/precache_referrer_host_table.h"
+
+#include "sql/connection.h"
+#include "sql/statement.h"
+
+using sql::Statement;
+
+namespace precache {
+
+const int64_t PrecacheReferrerHostEntry::INVALID_ID = -1;
+
+PrecacheReferrerHostTable::PrecacheReferrerHostTable() : db_(NULL) {}
+
+PrecacheReferrerHostTable::~PrecacheReferrerHostTable() {}
+
+bool PrecacheReferrerHostTable::Init(sql::Connection* db) {
+  DCHECK(!db_);  // Init must only be called once.
+  DCHECK(db);    // The database connection must be non-NULL.
+  db_ = db;
+  return CreateTableIfNonExistent();
+}
+
+PrecacheReferrerHostEntry PrecacheReferrerHostTable::GetReferrerHost(

[bengr, 2016/08/11 18:49:15]

Can this method be const?

[Raj, 2016/08/12 19:04:21]

Actually const. But cannot be const. :)
db_ is being accessed.

+    const std::string& referrer_host) {
+  Statement statement(db_->GetCachedStatement(
+      SQL_FROM_HERE,
+      "SELECT id, referrer_host, manifest_id, time "
+      "FROM precache_referrer_hosts WHERE referrer_host=?"));
+
+  statement.BindString(0, referrer_host);
+  if (statement.Step()) {
+    return PrecacheReferrerHostEntry(
+        statement.ColumnInt64(0), GURL(statement.ColumnString(1)),
+        statement.ColumnInt64(2),
+        base::Time::FromInternalValue(statement.ColumnInt64(3)));
+  }
+  return PrecacheReferrerHostEntry(PrecacheReferrerHostEntry::INVALID_ID,
+                                   GURL(), 0, base::Time());
+}
+
+int64_t PrecacheReferrerHostTable::UpdateReferrerHost(
+    const std::string& referrer_host,
+    int64_t manifest_id,
+    const base::Time& time) {
+  Statement statement(
+      db_->GetCachedStatement(SQL_FROM_HERE,
+                              "INSERT INTO precache_referrer_hosts "
+                              "(id, referrer_host, manifest_id, time) "
+                              "VALUES(NULL, ?, ?, ?)"));
+
+  statement.BindString(0, referrer_host);
+  statement.BindInt64(1, manifest_id);
+  statement.BindInt64(2, time.ToInternalValue());
+  if (statement.Run())
+    return db_->GetLastInsertRowId();
+  return -1;
+}
+
+void PrecacheReferrerHostTable::DeleteAllEntriesBefore(
+    const base::Time& delete_end) {
+  Statement statement(db_->GetCachedStatement(
+      SQL_FROM_HERE, "DELETE FROM precache_referrer_hosts WHERE time < ?"));
+  statement.BindInt64(0, delete_end.ToInternalValue());
+  statement.Run();
+}
+
+void PrecacheReferrerHostTable::DeleteAll() {
+  Statement statement(
+      db_->GetCachedStatement(SQL_FROM_HERE, "DELETE FROM precache_urls"));

[sclittle, 2016/08/11 22:52:36]

Update this to say "precache_referrer_hosts".

Could you please add tests for this file?

[Raj, 2016/08/12 19:04:21]

Done.
Adding tests.

+
+  statement.Run();
+}
+
+bool PrecacheReferrerHostTable::CreateTableIfNonExistent() {
+  return db_->Execute(
+      "CREATE TABLE IF NOT EXISTS precache_referrer_hosts "
+      "(id INTEGER PRIMARY KEY, referrer_host TEXT KEY, manifest_id INTEGER, "
+      "time INTEGER)");
+}
+
+}  // namespace precache