// record_store_test_randomiter.cpp
/**
* Copyright (C) 2014 MongoDB Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see .
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the GNU Affero General Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#include "mongo/platform/basic.h"
#include "mongo/db/record_id.h"
#include "mongo/db/storage/record_data.h"
#include "mongo/db/storage/record_store.h"
#include "mongo/db/storage/record_store_test_harness.h"
#include "mongo/unittest/unittest.h"
namespace mongo {
namespace {
using std::unique_ptr;
using std::set;
using std::string;
using std::stringstream;
// Create a random iterator for empty record store.
TEST(RecordStoreTestHarness, GetRandomIteratorEmpty) {
const auto harnessHelper(newRecordStoreHarnessHelper());
unique_ptr rs(harnessHelper->newNonCappedRecordStore());
{
ServiceContext::UniqueOperationContext opCtx(harnessHelper->newOperationContext());
ASSERT_EQUALS(0, rs->numRecords(opCtx.get()));
}
{
ServiceContext::UniqueOperationContext opCtx(harnessHelper->newOperationContext());
auto cursor = rs->getRandomCursor(opCtx.get());
// returns NULL if getRandomCursor is not supported
if (!cursor) {
return;
}
ASSERT(!cursor->next());
}
}
// Insert multiple records and create a random iterator for the record store
TEST(RecordStoreTestHarness, GetRandomIteratorNonEmpty) {
const auto harnessHelper(newRecordStoreHarnessHelper());
unique_ptr rs(harnessHelper->newNonCappedRecordStore());
{
ServiceContext::UniqueOperationContext opCtx(harnessHelper->newOperationContext());
ASSERT_EQUALS(0, rs->numRecords(opCtx.get()));
}
const unsigned nToInsert =
5000; // should be non-trivial amount, so we get multiple btree levels
RecordId locs[nToInsert];
for (unsigned i = 0; i < nToInsert; i++) {
ServiceContext::UniqueOperationContext opCtx(harnessHelper->newOperationContext());
{
stringstream ss;
ss << "record " << i;
string data = ss.str();
WriteUnitOfWork uow(opCtx.get());
StatusWith res =
rs->insertRecord(opCtx.get(), data.c_str(), data.size() + 1, false);
ASSERT_OK(res.getStatus());
locs[i] = res.getValue();
uow.commit();
}
}
{
ServiceContext::UniqueOperationContext opCtx(harnessHelper->newOperationContext());
ASSERT_EQUALS(nToInsert, rs->numRecords(opCtx.get()));
}
set remain(locs, locs + nToInsert);
{
ServiceContext::UniqueOperationContext opCtx(harnessHelper->newOperationContext());
auto cursor = rs->getRandomCursor(opCtx.get());
// returns NULL if getRandomCursor is not supported
if (!cursor) {
return;
}
// Iterate documents and mark those visited, but let at least one remain
for (unsigned i = 0; i < nToInsert - 1; i++) {
// Get a new cursor once in a while, shouldn't affect things
if (i % (nToInsert / 8) == 0) {
cursor = rs->getRandomCursor(opCtx.get());
}
remain.erase(cursor->next()->id); // can happen more than once per doc
}
ASSERT(!remain.empty());
ASSERT(cursor->next());
// We should have at least visited a quarter of the items if we're any random at all
// The expected fraction of visited records is 62.3%.
ASSERT_LT(remain.size(), nToInsert * 3 / 4);
}
}
// Insert a single record. Create a random iterator pointing to that single record.
// Then check we'll retrieve the record.
TEST(RecordStoreTestHarness, GetRandomIteratorSingleton) {
const auto harnessHelper(newRecordStoreHarnessHelper());
unique_ptr rs(harnessHelper->newNonCappedRecordStore());
{
ServiceContext::UniqueOperationContext opCtx(harnessHelper->newOperationContext());
ASSERT_EQ(0, rs->numRecords(opCtx.get()));
}
// Insert one record.
RecordId idToRetrieve;
{
ServiceContext::UniqueOperationContext opCtx(harnessHelper->newOperationContext());
WriteUnitOfWork uow(opCtx.get());
StatusWith res = rs->insertRecord(opCtx.get(), "some data", 10, false);
ASSERT_OK(res.getStatus());
idToRetrieve = res.getValue();
uow.commit();
}
// Double-check that the record store has one record in it now.
{
ServiceContext::UniqueOperationContext opCtx(harnessHelper->newOperationContext());
ASSERT_EQ(1, rs->numRecords(opCtx.get()));
}
{
ServiceContext::UniqueOperationContext opCtx(harnessHelper->newOperationContext());
auto cursor = rs->getRandomCursor(opCtx.get());
// returns NULL if getRandomCursor is not supported
if (!cursor) {
return;
}
// We should be pointing at the only record in the store.
// Check deattaching / reattaching
cursor->save();
cursor->detachFromOperationContext();
opCtx.reset();
opCtx = harnessHelper->newOperationContext();
cursor->reattachToOperationContext(opCtx.get());
ASSERT_TRUE(cursor->restore());
auto record = cursor->next();
ASSERT_EQUALS(record->id, idToRetrieve);
// Iterator should either be EOF now, or keep returning the single existing document
for (int i = 0; i < 10; i++) {
record = cursor->next();
ASSERT(!record || record->id == idToRetrieve);
}
}
}
} // namespace
} // namespace mongo