R4R: Split the export command into reset and export

app/app.go

@@ -91,7 +91,7 @@ func MakeLatestCodec() *codec.Codec {
 	return cdc
 }
 
-func (app *IrisApp) ExportOrReplay(replayHeight int64) (replay bool, height int64) {
+func (app *IrisApp) ResetOrReplay(replayHeight int64) (replay bool, height int64) {
 	lastBlockHeight := app.BaseApp.LastBlockHeight()
 	if replayHeight > lastBlockHeight {
 		replayHeight = lastBlockHeight

app/v1/metrics.go

@@ -8,7 +8,7 @@ import (
 	cfg "github.com/tendermint/tendermint/config"
 )
 
-const MetricsSubsystem = "v0"
+const MetricsSubsystem = "v1"
 
 type Metrics struct {
 	InvariantFailure metrics.Counter

cmd/iris/main.go

@@ -61,6 +61,7 @@ func main() {
 		server.UnsafeResetAllCmd(ctx),
 		client.LineBreak,
 		tendermintCmd,
+		server.ResetCmd(ctx, cdc, resetAppState),
 		server.ExportCmd(ctx, cdc, exportAppStateAndTMValidators),
 		client.LineBreak,
 	)
@@ -84,18 +85,24 @@ func newApp(logger log.Logger, db dbm.DB, traceStore io.Writer, config *cfg.Inst
 }
 
 func exportAppStateAndTMValidators(ctx *server.Context,
-	logger log.Logger, db dbm.DB, traceStore io.Writer, height int64, forZeroHeight bool,
+	logger log.Logger, db dbm.DB, traceStore io.Writer, forZeroHeight bool,
 ) (json.RawMessage, []tmtypes.GenesisValidator, error) {
+	gApp := app.NewIrisApp(logger, db, ctx.Config.Instrumentation, traceStore)
+	return gApp.ExportAppStateAndValidators(forZeroHeight)
+}
+
+func resetAppState(ctx *server.Context,
+	logger log.Logger, db dbm.DB, traceStore io.Writer, height int64) error {
 	gApp := app.NewIrisApp(logger, db, ctx.Config.Instrumentation, traceStore)
 	if height > 0 {
-		if replay, replayHeight := gApp.ExportOrReplay(height); replay {
+		if replay, replayHeight := gApp.ResetOrReplay(height); replay {
 			_, err := startNodeAndReplay(ctx, gApp, replayHeight)
 			if err != nil {
-				return nil, nil, err
+				return err
 			}
 		}
 	}
-	return gApp.ExportAppStateAndValidators(forZeroHeight)
+	return nil
 }
 
 func startNodeAndReplay(ctx *server.Context, app *app.IrisApp, height int64) (n *node.Node, err error) {

docs/.vuepress/config.js

@@ -31,7 +31,8 @@ module.exports = {
                         ['How-to-install-irishub.md', 'Install'],
                         ['cli-client.md', 'CLI Client'],
                         ['light-client.md', 'Light Client'],
-                        ['export.md', 'Export'],
+                        ['reset.md', 'Reset Blockchain State'],
+                        ['export.md', 'Export Blockchain State'],
                         ['sentry.md', 'Sentry'],
                         ['tool.md', 'Tool'],
                         ['monitor.md', 'Monitor'],
@@ -160,6 +161,7 @@ module.exports = {
                         ['How-to-install-irishub.md', '安装'],
                         ['cli-client.md', '命令行客户端'],
                         ['light-client.md', '轻节点客户端(LCD)'],
+                        ['reset.md', '重置区块链状态'],
                         ['export.md', '导出区块链状态'],
                         ['sentry.md', '哨兵节点'],
                         ['tool.md', '调试工具'],

docs/software/export.md

@@ -2,33 +2,30 @@
 
 ## Description
 
-IRISnet can export blockchain state at any height and output json format string. Save the out json string to a json file and the json file can be used as genesis file of a new blockchain. This can be accomplished by command `iris export`
+IRISnet can export blockchain state and output json format string. Save the out json string to a json file and the json file can be used as genesis file of a new blockchain. This can be accomplished by command `iris export`.
+If you want to export the state of the historical block height, you need to [reset](reset.md) the blockchain state to the specified height. 
 
 ## Usage
 ```		
  iris export <flags>
 ```
-### Flags
+## Flags
 
-  | Name，shorthand     | type   | Required | Default  | Description    |		
+ | Name，shorthand     | type   | Required | Default  | Description    |		
  | ------------------- | -----  | -------- | -------- | -------------- |		
  | --for-zero-height   | bool   | false    | false    | Do some clean up work before exporting state. If you want use the exported state to start a new blockchain, please add this flag. Otherwise, just leave out it |		
- | --height            | int    | false    | 0        | Specify the height, default value is 0 which means to export the latest state |		
  | --home              | string | false    | $HOME/.iris       | Specify the directory which stores node config and blockchain data |		
  | --output-file       | string | false    | genesis.json |  Target file to save exported state |
 
-1. Export the latest blockchain state:
-```		
- iris export		
-```
+## Examples
 
-2. Export blockchain state at certain height 
+1. Export the current blockchain state 
 
 ```		
- iris export --height=10000		
+ iris export --home=<path_to_your_home>
 ```
 
-3. If you want to export the blockchain state at certain height  and use the exported state as genesis state of another blockchain
+2. If you want to export the the current blockchain state and use the exported state as genesis state of another blockchain
 ```		
-iris export --height=105000 --for-zero-height --home=<path_to_your_home>	
+iris export --for-zero-height --home=<path_to_your_home>	
 ```

docs/software/reset.md

@@ -0,0 +1,23 @@
+# Reset Blockchain State
+
+## Description
+
+IRISnet can reset blockchain state at any height. This can be accomplished by command `iris reset`.
+
+## Usage
+```		
+ iris reset <flags>
+```
+## Flags
+
+ | Name，shorthand     | type   | Required | Default  | Description    |		
+ | ------------------- | -----  | -------- | -------- | -------------- |		
+ | --height            | int    | false    | 0        | Specify the height, default value is 0 which means to export the latest state |		
+ | --home              | string | false    | $HOME/.iris       | Specify the directory which stores node config and blockchain data |		
+
+## Examples
+
+1. Reset the blockchain state to block 100:
+```		
+ iris reset --height 100 --home=<path_to_your_home>
+```

docs/zh/software/export.md

@@ -2,7 +2,8 @@
 
 ## 介绍
 
-这里介绍一种能导出区块链状态，并以json格式返回给用户。如果把返回的json字符串保存到一个json文件里，那么这个json文件可以作为一个新区块链网络的创世块。导出区块链状态所用的命令为`iris export`
+IRISnet支持导出区块链状态，并以json格式返回给用户。如果把返回的json字符串保存到一个json文件里，这个json文件可以作为一个新区块链网络的创世块。导出区块链状态所用的命令为`iris export`。
+如果想导出历史高度的状态,需要先[重置](reset.md)app状态到指定的高度。
 
 ## 用法
 
@@ -15,21 +16,16 @@ iris export <flags>
 | 名称，速记          | 类型   | 是否必填 | 默认值   | 介绍    |
 | ------------------- | -----  | -------- | -------- | -------------- |
 | --for-zero-height   | bool   | false    | false    | 导出数据之前做一些清理性的工作，如果不想以导出的数据启动一条新链，可以不加这个标志 |
-| --height            | int    | false    | 0        | 指定的高度，默认值为0表示导出当前高度状态 |
 | --home              | string | false    | $HOME/.iris | 指定存储配置和区块链数据的目录 |
 | --output-file       | string | false    | genesis.json |  存储导出状态的文件 |
 
 ## 示例
 
-1. 导出最新的区块链状态:
+1. 导出当前区块链状态
 ```
-iris export
+iris export --home=<path_to_your_home>
 ```
-2. 导出高度10000的区块链状态
+2. 如果想导出当前高度的区块链状态，并且以这个状态启动一条新链，可以尝试这个命令
 ```
-iris export --height=10000
-```
-3. 如果想导出105000高度的区块链状态，并且以这个状态启动一条新链，可以尝试这个命令
-```
-iris export --height=105000 --for-zero-height --home=<path_to_your_home>
+iris export --for-zero-height --home=<path_to_your_home>
 ```

docs/zh/software/reset.md

@@ -0,0 +1,23 @@
+# 重置区块链状态
+
+## 介绍
+
+IRISnet支持重置区块链状态到任意高度，这里介绍重置区块链状态所用的命令为`iris reset`。
+
+## 用法
+```		
+ iris reset <flags>
+```
+## 标志
+
+ | Name，shorthand     | type   | Required | Default  | Description    |		
+ | ------------------- | -----  | -------- | -------- | -------------- |		
+ | --height            | int    | false    | 0        | Specify the height, default value is 0 which means to export the latest state |		
+ | --home              | string | false    | $HOME/.iris       | Specify the directory which stores node config and blockchain data |		
+
+## 示例
+
+1. 重置区块链状态到区块100:
+```		
+ iris reset --height 100 --home=<path_to_your_home>
+```

server/constructors.go

@@ -20,7 +20,10 @@ type (
 
 	// AppExporter is a function that dumps all app state to
 	// JSON-serializable structure and returns the current validator set.
-	AppExporter func(*Context, log.Logger, dbm.DB, io.Writer, int64, bool) (json.RawMessage, []tmtypes.GenesisValidator, error)
+	AppExporter func(*Context, log.Logger, dbm.DB, io.Writer, bool) (json.RawMessage, []tmtypes.GenesisValidator, error)
+
+	// AppReset is a function that reset all app state to particular height
+	AppReset func(*Context, log.Logger, dbm.DB, io.Writer, int64) error
 )
 
 func openDB(rootDir string) (dbm.DB, error) {

server/export.go

@@ -14,7 +14,6 @@ import (
 )
 
 const (
-	flagHeight        = "height"
 	flagForZeroHeight = "for-zero-height"
 	flagOutputFile    = "output-file"
 )
@@ -51,12 +50,9 @@ func ExportCmd(ctx *Context, cdc *codec.Codec, appExporter AppExporter) *cobra.C
 			if err != nil {
 				return err
 			}
-			height := viper.GetInt64(flagHeight)
-			if height < 0 {
-				return errors.Errorf("Height must greater than or equal to zero")
-			}
+
 			forZeroHeight := viper.GetBool(flagForZeroHeight)
-			appState, validators, err := appExporter(ctx, ctx.Logger, db, traceWriter, height, forZeroHeight)
+			appState, validators, err := appExporter(ctx, ctx.Logger, db, traceWriter, forZeroHeight)
 			if err != nil {
 				return errors.Errorf("error exporting state: %v\n", err)
 			}
@@ -85,7 +81,6 @@ func ExportCmd(ctx *Context, cdc *codec.Codec, appExporter AppExporter) *cobra.C
 			return nil
 		},
 	}
-	cmd.Flags().Int64(flagHeight, 0, "Export state from a particular height (0 means latest height)")
 	cmd.Flags().Bool(flagForZeroHeight, false, "Export state to start at height zero (perform preproccessing)")
 	cmd.Flags().String(flagOutputFile, "genesis.json", "Target file to save exported state")
 	return cmd

server/reset.go

@@ -0,0 +1,58 @@
+package server
+
+import (
+	"fmt"
+
+	"github.com/irisnet/irishub/codec"
+	"github.com/pkg/errors"
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+)
+
+const (
+	flagHeight = "height"
+)
+
+// ResetCmd reset app state to particular height
+func ResetCmd(ctx *Context, cdc *codec.Codec, appReset AppReset) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "reset",
+		Short: "Reset app state to the specified height",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			home := viper.GetString("home")
+			traceWriterFile := viper.GetString(flagTraceStore)
+			emptyState, err := isEmptyState(home)
+			if err != nil {
+				return err
+			}
+
+			if emptyState {
+				fmt.Println("WARNING: State is not initialized.")
+				return nil
+			}
+
+			db, err := openDB(home)
+			if err != nil {
+				return err
+			}
+			traceWriter, err := openTraceWriter(traceWriterFile)
+			if err != nil {
+				return err
+			}
+			height := viper.GetInt64(flagHeight)
+			if height < 0 {
+				return errors.Errorf("Height must greater than or equal to zero")
+			}
+			err = appReset(ctx, ctx.Logger, db, traceWriter, height)
+			if err != nil {
+				return errors.Errorf("Error reset state: %v\n", err)
+			}
+
+			fmt.Printf("Reset app state to height %d successfully\n", height)
+			return nil
+		},
+	}
+	cmd.Flags().Int64(flagHeight, 0, "Reset state from a particular height (0 or greater than latest height means latest height)")
+	cmd.MarkFlagRequired(flagHeight)
+	return cmd
+}