Log metrics for loading SQLiteChannelIDStore

net/extras/sqlite/sqlite_channel_id_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 "net/extras/sqlite/sqlite_channel_id_store.h"
 
 #include <memory>
 #include <set>
 #include <utility>
 #include <vector>
@@ skipping 18 matching lines @@
 #include "sql/statement.h"
 #include "sql/transaction.h"
 #include "url/gurl.h"
 
 namespace {
 
 // Version number of the database.
 const int kCurrentVersionNumber = 6;
 const int kCompatibleVersionNumber = 6;
 
+// Used in the DomainBoundCerts.DBLoadStatus histogram to record the status of
+// the Channel ID database when loading it from disk. It reports reasons why the
+// db could fail to load, or that it was loaded successfully.
+// Do not change or re-use values.
+enum DbLoadStatus {
+  // The path for the directory containing the db doesn't exist and couldn't be
+  // created.
+  PATH_DOES_NOT_EXIST = 0,
+  // Unable to open the database.
+  FAILED_TO_OPEN = 1,
+  // Failed to migrate the db to the current version.
+  MIGRATION_FAILED = 2,
+  // Unable to execute SELECT statement to load contents from db.
+  INVALID_SELECT_STATEMENT = 3,
+  // New database successfully created.
+  NEW_DB = 4,
+  // Database successfully loaded.
+  LOADED = 5,
+  // Database loaded, but one or more keys were skipped.
+  LOADED_WITH_ERRORS = 6,
+  DB_LOAD_STATUS_MAX
+};
+
+void RecordDbLoadStatus(DbLoadStatus status) {
+  UMA_HISTOGRAM_ENUMERATION("DomainBoundCerts.DBLoadStatus", status,
+                            DB_LOAD_STATUS_MAX);
+}
+
 }  // namespace
 
 namespace net {
 
 // This class is designed to be shared between any calling threads and the
 // background task runner. It batches operations and commits them on a timer.
 class SQLiteChannelIDStore::Backend
     : public base::RefCountedThreadSafe<SQLiteChannelIDStore::Backend> {
  public:
   Backend(
@@ skipping 120 matching lines @@
   DCHECK(background_task_runner_->RunsTasksOnCurrentThread());
 
   // This method should be called only once per instance.
   DCHECK(!db_.get());
 
   base::TimeTicks start = base::TimeTicks::Now();
 
   // Ensure the parent directory for storing certs is created before reading
   // from it.
   const base::FilePath dir = path_.DirName();
-  if (!base::PathExists(dir) && !base::CreateDirectory(dir))
+  if (!base::PathExists(dir) && !base::CreateDirectory(dir)) {
+    RecordDbLoadStatus(PATH_DOES_NOT_EXIST);
     return;
+  }
 
   db_.reset(new sql::Connection);
   db_->set_histogram_tag("DomainBoundCerts");
 
   // Unretained to avoid a ref loop with db_.
   db_->set_error_callback(
       base::Bind(&SQLiteChannelIDStore::Backend::DatabaseErrorCallback,
                  base::Unretained(this)));
 
+  DbLoadStatus load_result = LOADED;
+  if (!base::PathExists(path_)) {
+    load_result = NEW_DB;
+  }
+
   if (!db_->Open(path_)) {
     NOTREACHED() << "Unable to open cert DB.";
     if (corruption_detected_)
       KillDatabase();
     db_.reset();
+    RecordDbLoadStatus(FAILED_TO_OPEN);
     return;
   }
 
   if (!EnsureDatabaseVersion()) {
     NOTREACHED() << "Unable to open cert DB.";
     if (corruption_detected_)
       KillDatabase();
     meta_table_.Reset();
     db_.reset();
+    RecordDbLoadStatus(MIGRATION_FAILED);
     return;
   }
 
   db_->Preload();
 
   // Slurp all the certs into the out-vector.
   sql::Statement smt(db_->GetUniqueStatement(
       "SELECT host, private_key, creation_time FROM channel_id"));
   if (!smt.is_valid()) {
     if (corruption_detected_)
       KillDatabase();
     meta_table_.Reset();
     db_.reset();
+    RecordDbLoadStatus(INVALID_SELECT_STATEMENT);
     return;
   }
 
   while (smt.Step()) {
     std::vector<uint8_t> private_key_from_db;
     smt.ColumnBlobAsVector(1, &private_key_from_db);
     std::unique_ptr<crypto::ECPrivateKey> key(
         crypto::ECPrivateKey::CreateFromPrivateKeyInfo(private_key_from_db));
-    if (!key)
+    if (!key) {
+      load_result = LOADED_WITH_ERRORS;
       continue;
+    }
     std::unique_ptr<DefaultChannelIDStore::ChannelID> channel_id(
         new DefaultChannelIDStore::ChannelID(
             smt.ColumnString(0),  // host
             base::Time::FromInternalValue(smt.ColumnInt64(2)), std::move(key)));
     channel_ids->push_back(std::move(channel_id));
   }
 
   UMA_HISTOGRAM_COUNTS_10000(
       "DomainBoundCerts.DBLoadedCount",
       static_cast<base::HistogramBase::Sample>(channel_ids->size()));
   base::TimeDelta load_time = base::TimeTicks::Now() - start;
   UMA_HISTOGRAM_CUSTOM_TIMES("DomainBoundCerts.DBLoadTime",
                              load_time,
                              base::TimeDelta::FromMilliseconds(1),
                              base::TimeDelta::FromMinutes(1),
                              50);
   DVLOG(1) << "loaded " << channel_ids->size() << " in "
            << load_time.InMilliseconds() << " ms";
+  RecordDbLoadStatus(load_result);
 }
 
 bool SQLiteChannelIDStore::Backend::EnsureDatabaseVersion() {
   // Version check.
   if (!meta_table_.Init(
           db_.get(), kCurrentVersionNumber, kCompatibleVersionNumber)) {
     return false;
   }
 
   if (meta_table_.GetCompatibleVersionNumber() > kCurrentVersionNumber) {
     LOG(WARNING) << "Server bound cert database is too new.";
     return false;
   }
 
   int cur_version = meta_table_.GetVersionNumber();
+  UMA_HISTOGRAM_EXACT_LINEAR("DomainBoundCerts.DBVersion", cur_version,
+                             kCurrentVersionNumber + 1);
 
   sql::Transaction transaction(db_.get());
   if (!transaction.Begin())
     return false;
 
   // Create new table if it doesn't already exist
   if (!db_->DoesTableExist("channel_id")) {
     if (!db_->Execute(
             "CREATE TABLE channel_id ("
             "host TEXT NOT NULL UNIQUE PRIMARY KEY,"
@@ skipping 374 matching lines @@
   backend_->SetForceKeepSessionState();
 }
 
 SQLiteChannelIDStore::~SQLiteChannelIDStore() {
   backend_->Close();
   // We release our reference to the Backend, though it will probably still have
   // a reference if the background task runner has not run Close() yet.
 }
 
 }  // namespace net