package kvstore
|
|
|
|
import (
|
|
"bytes"
|
|
"encoding/binary"
|
|
"encoding/json"
|
|
"fmt"
|
|
|
|
dbm "github.com/tendermint/tm-db"
|
|
|
|
"github.com/tendermint/tendermint/abci/example/code"
|
|
"github.com/tendermint/tendermint/abci/types"
|
|
"github.com/tendermint/tendermint/version"
|
|
)
|
|
|
|
var (
|
|
stateKey = []byte("stateKey")
|
|
kvPairPrefixKey = []byte("kvPairKey:")
|
|
|
|
ProtocolVersion uint64 = 0x1
|
|
)
|
|
|
|
type State struct {
|
|
db dbm.DB
|
|
Size int64 `json:"size"`
|
|
Height int64 `json:"height"`
|
|
AppHash []byte `json:"app_hash"`
|
|
}
|
|
|
|
func loadState(db dbm.DB) State {
|
|
var state State
|
|
state.db = db
|
|
stateBytes, err := db.Get(stateKey)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
if len(stateBytes) == 0 {
|
|
return state
|
|
}
|
|
err = json.Unmarshal(stateBytes, &state)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
return state
|
|
}
|
|
|
|
func saveState(state State) {
|
|
stateBytes, err := json.Marshal(state)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
err = state.db.Set(stateKey, stateBytes)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
}
|
|
|
|
func prefixKey(key []byte) []byte {
|
|
return append(kvPairPrefixKey, key...)
|
|
}
|
|
|
|
//---------------------------------------------------
|
|
|
|
var _ types.Application = (*Application)(nil)
|
|
|
|
type Application struct {
|
|
types.BaseApplication
|
|
|
|
state State
|
|
RetainBlocks int64 // blocks to retain after commit (via ResponseCommit.RetainHeight)
|
|
}
|
|
|
|
func NewApplication() *Application {
|
|
state := loadState(dbm.NewMemDB())
|
|
return &Application{state: state}
|
|
}
|
|
|
|
func (app *Application) Info(req types.RequestInfo) (resInfo types.ResponseInfo) {
|
|
return types.ResponseInfo{
|
|
Data: fmt.Sprintf("{\"size\":%v}", app.state.Size),
|
|
Version: version.ABCIVersion,
|
|
AppVersion: ProtocolVersion,
|
|
LastBlockHeight: app.state.Height,
|
|
LastBlockAppHash: app.state.AppHash,
|
|
}
|
|
}
|
|
|
|
// tx is either "key=value" or just arbitrary bytes
|
|
func (app *Application) DeliverTx(req types.RequestDeliverTx) types.ResponseDeliverTx {
|
|
var key, value []byte
|
|
parts := bytes.Split(req.Tx, []byte("="))
|
|
if len(parts) == 2 {
|
|
key, value = parts[0], parts[1]
|
|
} else {
|
|
key, value = req.Tx, req.Tx
|
|
}
|
|
|
|
err := app.state.db.Set(prefixKey(key), value)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
app.state.Size++
|
|
|
|
events := []types.Event{
|
|
{
|
|
Type: "app",
|
|
Attributes: []types.EventAttribute{
|
|
{Key: []byte("creator"), Value: []byte("Cosmoshi Netowoko"), Index: true},
|
|
{Key: []byte("key"), Value: key, Index: true},
|
|
{Key: []byte("index_key"), Value: []byte("index is working"), Index: true},
|
|
{Key: []byte("noindex_key"), Value: []byte("index is working"), Index: false},
|
|
},
|
|
},
|
|
}
|
|
|
|
return types.ResponseDeliverTx{Code: code.CodeTypeOK, Events: events}
|
|
}
|
|
|
|
func (app *Application) CheckTx(req types.RequestCheckTx) types.ResponseCheckTx {
|
|
return types.ResponseCheckTx{Code: code.CodeTypeOK, GasWanted: 1}
|
|
}
|
|
|
|
func (app *Application) Commit() types.ResponseCommit {
|
|
// Using a memdb - just return the big endian size of the db
|
|
appHash := make([]byte, 8)
|
|
binary.PutVarint(appHash, app.state.Size)
|
|
app.state.AppHash = appHash
|
|
app.state.Height++
|
|
saveState(app.state)
|
|
|
|
resp := types.ResponseCommit{Data: appHash}
|
|
if app.RetainBlocks > 0 && app.state.Height >= app.RetainBlocks {
|
|
resp.RetainHeight = app.state.Height - app.RetainBlocks + 1
|
|
}
|
|
return resp
|
|
}
|
|
|
|
// Returns an associated value or nil if missing.
|
|
func (app *Application) Query(reqQuery types.RequestQuery) (resQuery types.ResponseQuery) {
|
|
if reqQuery.Prove {
|
|
value, err := app.state.db.Get(prefixKey(reqQuery.Data))
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
if value == nil {
|
|
resQuery.Log = "does not exist"
|
|
} else {
|
|
resQuery.Log = "exists"
|
|
}
|
|
resQuery.Index = -1 // TODO make Proof return index
|
|
resQuery.Key = reqQuery.Data
|
|
resQuery.Value = value
|
|
resQuery.Height = app.state.Height
|
|
|
|
return
|
|
}
|
|
|
|
resQuery.Key = reqQuery.Data
|
|
value, err := app.state.db.Get(prefixKey(reqQuery.Data))
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
if value == nil {
|
|
resQuery.Log = "does not exist"
|
|
} else {
|
|
resQuery.Log = "exists"
|
|
}
|
|
resQuery.Value = value
|
|
resQuery.Height = app.state.Height
|
|
|
|
return resQuery
|
|
}
|