Add the LoggedIn Predictor, to detect which websites a user is likely

chrome/browser/predictors/logged_in_predictor_table.cc

+// Copyright (c) 2013 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 "chrome/browser/predictors/logged_in_predictor_table.h"
+
+#include <algorithm>
+#include <utility>
+#include "base/logging.h"
+#include "base/metrics/histogram.h"
+#include "base/stringprintf.h"
+#include "content/public/browser/browser_thread.h"
+#include "net/base/registry_controlled_domains/registry_controlled_domain.h"
+#include "sql/statement.h"
+
+using content::BrowserThread;
+using sql::Statement;
+using std::string;
+
+namespace {
+
+const char kTableName[] = "logged_in_predictor";
+
+}  // namespace
+
+namespace predictors {
+
+LoggedInPredictorTable::LoggedInPredictorTable()
+    : PredictorTableBase() {
+}
+
+LoggedInPredictorTable::~LoggedInPredictorTable() {
+}
+
+string LoggedInPredictorTable::GetKey(const GURL& url) {
+  string effective_domain(
+      net::RegistryControlledDomainService::GetDomainAndRegistry(url.host()));
+  if (effective_domain.empty())
+    effective_domain = url.host();
+
+  if (!effective_domain.empty() && effective_domain[0] == '.')

[Shishir, 2013/04/16 21:22:04]

Comment on this code.

[tburkard, 2013/04/16 21:47:19]

Done.

+    return effective_domain.substr(1);
+  return effective_domain;
+}
+
+void LoggedInPredictorTable::Add(const GURL& url) {
+  CHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
+  if (CantAccessDatabase())
+    return;
+
+  Statement statement(DB()->GetCachedStatement(SQL_FROM_HERE,
+      base::StringPrintf("INSERT OR IGNORE INTO %s (domain, time) VALUES (?,?)",
+                         kTableName).c_str()));
+
+  statement.BindString(0, GetKey(url));
+  statement.BindInt64(1, base::Time::Now().ToInternalValue());
+
+  statement.Run();
+}
+
+void LoggedInPredictorTable::Exists(const GURL& url, bool* is_present,
+                                    bool* lookup_succeeded) {
+  CHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
+  *lookup_succeeded = false;
+  if (CantAccessDatabase())
+    return;
+
+  Statement statement(DB()->GetUniqueStatement(

[Shishir, 2013/04/16 21:22:04]

GetCachedStatement.

[tburkard, 2013/04/16 21:47:19]

Done.

+      base::StringPrintf("SELECT count(*) FROM %s WHERE domain=?",
+                         kTableName).c_str()));
+
+  statement.BindString(0, GetKey(url));
+
+  if (statement.Step()) {
+    *is_present = (statement.ColumnInt(0) > 0);
+    *lookup_succeeded = true;
+  }
+}
+
+void LoggedInPredictorTable::DeleteAllCreatedBetween(
+    const base::Time& delete_begin, const base::Time& delete_end) {
+  CHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
+  if (CantAccessDatabase())
+    return;
+
+  Statement statement(DB()->GetCachedStatement(SQL_FROM_HERE,
+      base::StringPrintf("DELETE FROM %s WHERE time >= ? AND time <= ?",
+                         kTableName).c_str()));
+
+  statement.BindInt64(0, delete_begin.ToInternalValue());
+  statement.BindInt64(1, delete_end.ToInternalValue());
+
+  statement.Run();
+}
+
+void LoggedInPredictorTable::CreateTableIfNonExistent() {
+  CHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
+  if (CantAccessDatabase())
+    return;
+
+  const char* table_creator =
+      "CREATE TABLE %s ( "

[Shishir, 2013/04/16 21:22:04]

Will probably fit in one line?

[tburkard, 2013/04/16 21:47:19]

Done.

+      "domain TEXT, "
+      "time INTEGER, "
+      "PRIMARY KEY(domain))";
+
+  sql::Connection* db = DB();
+  bool success =

[Shishir, 2013/04/16 21:22:04]

Since you have only one table, put

if (db->DoesTableExist(kTableName))
  return;

at the top and here:

if (!db->execute...)
  ResetDB();

[tburkard, 2013/04/16 21:47:19]

Done.

+      (db->DoesTableExist(kTableName) ||
+       db->Execute(base::StringPrintf(table_creator, kTableName).c_str()));
+
+  if (!success)
+    ResetDB();
+}
+
+void LoggedInPredictorTable::LogDatabaseStats()  {
+  CHECK(BrowserThread::CurrentlyOn(BrowserThread::DB));
+  if (CantAccessDatabase())
+    return;
+
+  Statement statement(DB()->GetUniqueStatement(
+      base::StringPrintf("SELECT count(*) FROM %s",

[Shishir, 2013/04/16 21:22:04]

one line?

[tburkard, 2013/04/16 21:47:19]

Done.

+                         kTableName).c_str()));
+  if (statement.Step())
+    UMA_HISTOGRAM_COUNTS("LoggedInPredictor.TableRowCount",
+                         statement.ColumnInt(0));
+}
+
+}  // namespace predictors