core: move blockdb into core package and minor change on governance interface (#110)

Since third party apps will possibly implement their only blockdb class,
it make sense for the interface to be in core.
Also add GetNumShards into the governance interface.

1 files changed, 132 insertions, 0 deletions

diff --git a/core/blockdb/level-db_test.go b/core/blockdb/level-db_test.go
new file mode 100644
index 0000000..06829f0
--- /dev/null
+++ b/core/blockdb/level-db_test.go
@@ -0,0 +1,132 @@
+// Copyright 2018 The dexon-consensus-core Authors
+// This file is part of the dexon-consensus-core library.
+//
+// The dexon-consensus-core library is free software: you can redistribute it
+// and/or modify it under the terms of the GNU Lesser General Public License as
+// published by the Free Software Foundation, either version 3 of the License,
+// or (at your option) any later version.
+//
+// The dexon-consensus-core library 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 Lesser
+// General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the dexon-consensus-core library. If not, see
+// <http://www.gnu.org/licenses/>.
+
+package blockdb
+
+import (
+	"fmt"
+	"testing"
+	"time"
+
+	"os"
+
+	"github.com/stretchr/testify/suite"
+
+	"github.com/dexon-foundation/dexon-consensus-core/common"
+	"github.com/dexon-foundation/dexon-consensus-core/core/types"
+)
+
+type LevelDBTestSuite struct {
+	suite.Suite
+}
+
+func (s *LevelDBTestSuite) TestBasicUsage() {
+	dbName := fmt.Sprintf("test-db-%v.db", time.Now().UTC())
+	db, err := NewLevelDBBackedBlockDB(dbName)
+	s.Require().Nil(err)
+	defer func(dbName string) {
+		err = db.Close()
+		s.Nil(err)
+		err = os.RemoveAll(dbName)
+		s.Nil(err)
+	}(dbName)
+
+	// Queried something from an empty database.
+	hash1 := common.NewRandomHash()
+	_, err = db.Get(hash1)
+	s.Equal(ErrBlockDoesNotExist, err)
+
+	// Update on an empty database should not success.
+	validator1 := types.ValidatorID{Hash: common.NewRandomHash()}
+	block1 := types.Block{
+		ProposerID: validator1,
+		Hash:       hash1,
+		Position: types.Position{
+			Height: 1,
+		},
+	}
+	err = db.Update(block1)
+	s.Equal(ErrBlockDoesNotExist, err)
+
+	// Put to create a new record should just work fine.
+	err = db.Put(block1)
+	s.Nil(err)
+
+	// Get it back should work fine.
+	queried, err := db.Get(block1.Hash)
+	s.Nil(err)
+	s.Equal(queried.ProposerID, block1.ProposerID)
+
+	// Test Update.
+	now := time.Now().UTC()
+	queried.Timestamp = now
+
+	err = db.Update(queried)
+	s.Nil(err)
+
+	// Try to get it back via ValidatorID and height.
+	queried, err = db.Get(block1.Hash)
+
+	s.Nil(err)
+	s.Equal(now, queried.Timestamp)
+}
+
+func (s *LevelDBTestSuite) TestSyncIndex() {
+	dbName := fmt.Sprintf("test-db-%v-si.db", time.Now().UTC())
+	db, err := NewLevelDBBackedBlockDB(dbName)
+	s.Require().Nil(err)
+	defer func(dbName string) {
+		err = db.Close()
+		s.Nil(err)
+		err = os.RemoveAll(dbName)
+		s.Nil(err)
+	}(dbName)
+
+	// Create some blocks.
+	blocks := [10]types.Block{}
+	for i := range blocks {
+		block := types.Block{
+			ProposerID: types.ValidatorID{Hash: common.NewRandomHash()},
+			Hash:       common.NewRandomHash(),
+			Position: types.Position{
+				Height: uint64(i),
+			},
+		}
+		db.Put(block)
+		blocks[i] = block
+	}
+
+	// Save blocks to db.
+	err = db.Close()
+	s.Nil(err)
+
+	// Load back blocks(syncIndex is called).
+	db, err = NewLevelDBBackedBlockDB(dbName)
+	s.Require().Nil(err)
+
+	// Verify result.
+	for _, block := range blocks {
+		queried, err := db.Get(block.Hash)
+		s.Nil(err)
+		s.Equal(block.ProposerID, queried.ProposerID)
+		s.Equal(block.Position.Height, queried.Position.Height)
+	}
+}
+
+func TestLevelDB(t *testing.T) {
+	suite.Run(t, new(LevelDBTestSuite))
+}