TableMock + framework for mock classes

Summary:
This diff replaces BlockBasedTable in flush_job_test with TableMock, making it depend on less things and making it closer to an unit test than integration test.

It also introduces a framework to compile mock classes -- Any file named *mock.cc will not be compiled into the build. It will only get compiled into the tests. What way we can mock out most other classes, Version, VersionSet, DBImpl, etc.

Test Plan: flush_job_test

Reviewers: ljin, rven, yhchiang, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D27681

Makefile

@@ -76,11 +76,11 @@ CXXFLAGS += $(WARNING_FLAGS) -I. -I./include $(PLATFORM_CXXFLAGS) $(OPT) -Woverl
 LDFLAGS += $(PLATFORM_LDFLAGS)
 
 LIBOBJECTS = $(SOURCES:.cc=.o)
-LIBOBJECTS += $(SOURCESCPP:.cpp=.o)
 MEMENVOBJECTS = $(MEMENV_SOURCES:.cc=.o)
+MOCKOBJECTS = $(MOCK_SOURCES:.cc=.o)
 
 TESTUTIL = ./util/testutil.o
-TESTHARNESS = ./util/testharness.o $(TESTUTIL)
+TESTHARNESS = ./util/testharness.o $(TESTUTIL) $(MOCKOBJECTS)
 BENCHHARNESS = ./util/benchharness.o
 VALGRIND_ERROR = 2
 VALGRIND_DIR = build_tools/VALGRIND_LOGS

build_tools/build_detect_platform

@@ -173,14 +173,15 @@ DIRS="util db table utilities"
 set -f # temporarily disable globbing so that our patterns arent expanded
 PRUNE_TEST="-name *test*.cc -prune"
 PRUNE_BENCH="-name *bench*.cc -prune"
-PORTABLE_FILES=`cd "$ROCKSDB_ROOT"; find $DIRS $PRUNE_TEST -o $PRUNE_BENCH -o -name '*.cc' -print | sort | tr "\n" " "`
-PORTABLE_CPP=`cd "$ROCKSDB_ROOT"; find $DIRS $PRUNE_TEST -o $PRUNE_BENCH -o -name '*.cpp' -print | sort | tr "\n" " "`
+PRUNE_MOCK="-name *mock*.cc -prune"
+PORTABLE_FILES=`cd "$ROCKSDB_ROOT"; find $DIRS $PRUNE_TEST -o $PRUNE_BENCH -o $PRUNE_MOCK -o -name '*.cc' -print | sort | tr "\n" " "`
+MOCK_SOURCES=`cd "$ROCKSDB_ROOT"; find $DIRS -name '*mock.cc' -print | sort | tr "\n" " "`
 set +f # re-enable globbing
 
 # The sources consist of the portable files, plus the platform-specific port
 # file.
 echo "SOURCES=$PORTABLE_FILES $GENERIC_PORT_FILES $PORT_FILES" >> "$OUTPUT"
-echo "SOURCESCPP=$PORTABLE_CPP" >> "$OUTPUT"
+echo "MOCK_SOURCES=$MOCK_SOURCES" >> "$OUTPUT"
 echo "MEMENV_SOURCES=helpers/memenv/memenv.cc" >> "$OUTPUT"
 
 if [ "$CROSS_COMPILE" = "true" -o "$FBCODE_BUILD" = "true" ]; then

db/flush_job_test.cc

@@ -3,19 +3,22 @@
 //  LICENSE file in the root directory of this source tree. An additional grant
 //  of patent rights can be found in the PATENTS file in the same directory.
 
+#include <map>
+#include <string>
+
 #include "db/flush_job.h"
 #include "db/column_family.h"
 #include "db/version_set.h"
 #include "rocksdb/cache.h"
 #include "util/testharness.h"
 #include "util/testutil.h"
+#include "table/mock_table.h"
 
 namespace rocksdb {
 
 // TODO(icanadi) Mock out everything else:
 // 1. VersionSet
-// 2. TableBuilder
-// 3. Memtable
+// 2. Memtable
 class FlushJobTest {
  public:
   FlushJobTest()
@@ -24,14 +27,16 @@ class FlushJobTest {
         table_cache_(NewLRUCache(50000, 16, 8)),
         versions_(new VersionSet(dbname_, &db_options_, env_options_,
                                  table_cache_.get(), &write_controller_)),
-        shutting_down_(false) {
+        shutting_down_(false),
+        mock_table_factory_(new MockTableFactory()) {
     ASSERT_OK(env_->CreateDirIfMissing(dbname_));
     db_options_.db_paths.emplace_back(dbname_,
                                       std::numeric_limits<uint64_t>::max());
     // TODO(icanadi) Remove this once we mock out VersionSet
     NewDB();
     std::vector<ColumnFamilyDescriptor> column_families;
-    column_families.emplace_back();
+    cf_options_.table_factory = mock_table_factory_;
+    column_families.emplace_back(kDefaultColumnFamilyName, cf_options_);
 
     ASSERT_OK(versions_->Recover(column_families, false));
   }
@@ -69,6 +74,7 @@ class FlushJobTest {
   port::Mutex mutex_;
   std::atomic<bool> shutting_down_;
   FileNumToPathIdMap pending_outputs_;
+  std::shared_ptr<MockTableFactory> mock_table_factory_;
 };
 
 TEST(FlushJobTest, Empty) {
@@ -89,10 +95,13 @@ TEST(FlushJobTest, NonEmpty) {
   auto new_mem = new MemTable(cfd->internal_comparator(), *cfd->ioptions(),
                               *cfd->GetLatestMutableCFOptions());
   new_mem->Ref();
+  std::map<std::string, std::string> inserted_keys;
   for (int i = 1; i < 10000; ++i) {
     std::string key(std::to_string(i));
     std::string value("value" + std::to_string(i));
     new_mem->Add(SequenceNumber(i), kTypeValue, key, value);
+    InternalKey internal_key(key, SequenceNumber(i), kTypeValue);
+    inserted_keys.insert({internal_key.Encode().ToString(), value});
   }
   cfd->imm()->Add(new_mem);
 
@@ -104,8 +113,7 @@ TEST(FlushJobTest, NonEmpty) {
   mutex_.Lock();
   ASSERT_OK(flush_job.Run());
   mutex_.Unlock();
-  // TODO(icanadi) once you have TableMock, verify that key-values are as
-  // expected
+  mock_table_factory_->AssertSingleFile(inserted_keys);
 }
 
 }  // namespace rocksdb

db/table_cache.cc

@@ -88,7 +88,6 @@ Status TableCache::FindTable(const EnvOptions& env_options,
       // We do not cache error results so that if the error is transient,
       // or somebody repairs the file, we recover automatically.
     } else {
-      assert(file.get() == nullptr);
       *handle = cache_->Insert(key, table_reader.release(), 1, &DeleteEntry);
     }
   }

table/mock_table.cc

@@ -0,0 +1,95 @@
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+
+#include "rocksdb/table_properties.h"
+#include "table/mock_table.h"
+#include "table/get_context.h"
+#include "db/dbformat.h"
+#include "port/port.h"
+#include "util/coding.h"
+
+namespace rocksdb {
+
+Iterator* MockTableReader::NewIterator(const ReadOptions&, Arena* arena) {
+  return new MockTableIterator(table_);
+}
+
+Status MockTableReader::Get(const ReadOptions&, const Slice& key,
+                            GetContext* get_context) {
+  std::unique_ptr<MockTableIterator> iter(new MockTableIterator(table_));
+  for (iter->Seek(key); iter->Valid(); iter->Next()) {
+    ParsedInternalKey parsed_key;
+    if (!ParseInternalKey(iter->key(), &parsed_key)) {
+      return Status::Corruption(Slice());
+    }
+
+    if (!get_context->SaveValue(parsed_key, iter->value())) {
+      break;
+    }
+  }
+  return Status::OK();
+}
+
+std::shared_ptr<const TableProperties> MockTableReader::GetTableProperties()
+    const {
+  return std::shared_ptr<const TableProperties>(new TableProperties());
+}
+
+MockTableFactory::MockTableFactory() : next_id_(1) {}
+
+Status MockTableFactory::NewTableReader(
+    const ImmutableCFOptions& ioptions, const EnvOptions& env_options,
+    const InternalKeyComparator& internal_key,
+    unique_ptr<RandomAccessFile>&& file, uint64_t file_size,
+    unique_ptr<TableReader>* table_reader) const {
+  uint32_t id = GetIDFromFile(file.get());
+
+  MutexLock lock_guard(&file_system_.mutex);
+
+  auto it = file_system_.files.find(id);
+  if (it == file_system_.files.end()) {
+    return Status::IOError("Mock file not found");
+  }
+
+  table_reader->reset(new MockTableReader(it->second));
+
+  return Status::OK();
+}
+
+TableBuilder* MockTableFactory::NewTableBuilder(
+    const ImmutableCFOptions& ioptions,
+    const InternalKeyComparator& internal_key, WritableFile* file,
+    const CompressionType compression_type,
+    const CompressionOptions& compression_opts) const {
+  uint32_t id = GetAndWriteNextID(file);
+
+  return new MockTableBuilder(id, &file_system_);
+}
+
+uint32_t MockTableFactory::GetAndWriteNextID(WritableFile* file) const {
+  uint32_t next_id = next_id_.fetch_add(1);
+  char buf[4];
+  EncodeFixed32(buf, next_id);
+  file->Append(Slice(buf, 4));
+  return next_id;
+}
+
+uint32_t MockTableFactory::GetIDFromFile(RandomAccessFile* file) const {
+  char buf[4];
+  Slice result;
+  file->Read(0, 4, &result, buf);
+  assert(result.size() == 4);
+  return DecodeFixed32(buf);
+}
+
+void MockTableFactory::AssertSingleFile(
+    const std::map<std::string, std::string>& file_contents) {
+  ASSERT_EQ(file_system_.files.size(), 1U);
+  ASSERT_TRUE(file_contents == file_system_.files.begin()->second);
+}
+
+}  // namespace rocksdb

table/mock_table.h

@@ -0,0 +1,171 @@
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+//  Copyright (c) 2013, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+#pragma once
+#include <algorithm>
+#include <set>
+#include <memory>
+#include <map>
+#include <string>
+
+#include "rocksdb/table.h"
+#include "table/table_reader.h"
+#include "table/table_builder.h"
+#include "port/port.h"
+#include "util/mutexlock.h"
+#include "util/testharness.h"
+#include "util/testutil.h"
+
+namespace rocksdb {
+
+// NOTE this currently only supports bitwise comparator
+
+struct MockTableFileSystem {
+  port::Mutex mutex;
+  std::map<uint32_t, std::map<std::string, std::string>> files;
+};
+
+class MockTableReader : public TableReader {
+ public:
+  MockTableReader(const std::map<std::string, std::string>& table)
+      : table_(table) {}
+
+  Iterator* NewIterator(const ReadOptions&, Arena* arena) override;
+
+  Status Get(const ReadOptions&, const Slice& key,
+             GetContext* get_context) override;
+
+  uint64_t ApproximateOffsetOf(const Slice& key) override { return 0; }
+
+  virtual size_t ApproximateMemoryUsage() const override { return 0; }
+
+  void SetupForCompaction() override {}
+
+  std::shared_ptr<const TableProperties> GetTableProperties() const override;
+
+  ~MockTableReader() {}
+
+ private:
+  const std::map<std::string, std::string>& table_;
+};
+
+class MockTableIterator : public Iterator {
+ public:
+  explicit MockTableIterator(const std::map<std::string, std::string>& table)
+      : table_(table) {
+    itr_ = table_.end();
+  }
+
+  bool Valid() const { return itr_ == table_.end(); }
+
+  void SeekToFirst() { itr_ = table_.begin(); }
+
+  void SeekToLast() {
+    itr_ = table_.end();
+    --itr_;
+  }
+
+  void Seek(const Slice& target) {
+    std::string str_target(target.data(), target.size());
+    itr_ = table_.lower_bound(str_target);
+  }
+
+  void Next() { ++itr_; }
+
+  void Prev() {
+    if (itr_ == table_.begin()) {
+      itr_ = table_.end();
+    } else {
+      --itr_;
+    }
+  }
+
+  Slice key() const { return Slice(itr_->first); }
+
+  Slice value() const { return Slice(itr_->second); }
+
+  Status status() const { return Status::OK(); }
+
+ private:
+  const std::map<std::string, std::string>& table_;
+  std::map<std::string, std::string>::const_iterator itr_;
+};
+
+class MockTableBuilder : public TableBuilder {
+ public:
+  MockTableBuilder(uint32_t id, MockTableFileSystem* file_system)
+      : id_(id), file_system_(file_system) {}
+
+  // REQUIRES: Either Finish() or Abandon() has been called.
+  ~MockTableBuilder() {}
+
+  // Add key,value to the table being constructed.
+  // REQUIRES: key is after any previously added key according to comparator.
+  // REQUIRES: Finish(), Abandon() have not been called
+  void Add(const Slice& key, const Slice& value) override {
+    table_.insert({key.ToString(), value.ToString()});
+  }
+
+  // Return non-ok iff some error has been detected.
+  Status status() const override { return Status::OK(); }
+
+  Status Finish() override {
+    MutexLock lock_guard(&file_system_->mutex);
+    file_system_->files.insert({id_, table_});
+    return Status::OK();
+  }
+
+  void Abandon() override {}
+
+  uint64_t NumEntries() const override { return table_.size(); }
+
+  uint64_t FileSize() const override { return table_.size(); }
+
+ private:
+  uint32_t id_;
+  MockTableFileSystem* file_system_;
+  std::map<std::string, std::string> table_;
+};
+
+class MockTableFactory : public TableFactory {
+ public:
+  MockTableFactory();
+  const char* Name() const override { return "MockTable"; }
+  Status NewTableReader(const ImmutableCFOptions& ioptions,
+                        const EnvOptions& env_options,
+                        const InternalKeyComparator& internal_key,
+                        unique_ptr<RandomAccessFile>&& file, uint64_t file_size,
+                        unique_ptr<TableReader>* table_reader) const;
+
+  TableBuilder* NewTableBuilder(
+      const ImmutableCFOptions& ioptions,
+      const InternalKeyComparator& internal_key, WritableFile* file,
+      const CompressionType compression_type,
+      const CompressionOptions& compression_opts) const;
+
+  virtual Status SanitizeOptions(const DBOptions& db_opts,
+                                 const ColumnFamilyOptions& cf_opts) const {
+    return Status::OK();
+  }
+
+  virtual std::string GetPrintableTableOptions() const override {
+    return std::string();
+  }
+
+  // This function will assert that only a single file exists and that the
+  // contents are equal to file_contents
+  void AssertSingleFile(
+      const std::map<std::string, std::string>& file_contents);
+
+ private:
+  uint32_t GetAndWriteNextID(WritableFile* file) const;
+  uint32_t GetIDFromFile(RandomAccessFile* file) const;
+
+  mutable MockTableFileSystem file_system_;
+  mutable std::atomic<uint32_t> next_id_;
+};
+
+}  // namespace rocksdb