Simulate transactions by default to set gas automatically

PENDING.md

@@ -35,6 +35,8 @@ FEATURES
 * Gaia CLI  (`gaiacli`)
   * [cli] Cmds to query staking pool and params
   * [gov][cli] #2062 added `--proposal` flag to `submit-proposal` that allows a JSON file containing a proposal to be passed in
+  * [cli] \#2047 Setting the --gas flag value to 0 triggers a simulation of the tx before the actual execution. The gas estimate obtained via the simulation will be used as gas limit in the actual execution.
+  * [cli] \#2047 The --gas-adjustment flag can be used to adjust the estimate obtained via the simulation triggered by --gas=0.
 
 * Gaia
 

baseapp/baseapp.go

@@ -493,15 +493,14 @@ func validateBasicTxMsgs(msgs []sdk.Msg) sdk.Error {
 	return nil
 }
 
+// retrieve the context for the ante handler and store the tx bytes; store
+// the signing validators if the tx runs within the deliverTx() state.
 func (app *BaseApp) getContextForAnte(mode runTxMode, txBytes []byte) (ctx sdk.Context) {
 	// Get the context
-	if mode == runTxModeCheck || mode == runTxModeSimulate {
-		ctx = app.checkState.ctx.WithTxBytes(txBytes)
-	} else {
-		ctx = app.deliverState.ctx.WithTxBytes(txBytes)
+	ctx = getState(app, mode).ctx.WithTxBytes(txBytes)
+	if mode == runTxModeDeliver {
 		ctx = ctx.WithSigningValidators(app.signedValidators)
 	}
-
 	return
 }
 
@@ -567,6 +566,13 @@ func getState(app *BaseApp, mode runTxMode) *state {
 	return app.deliverState
 }
 
+func (app *BaseApp) initializeContext(ctx sdk.Context, mode runTxMode) sdk.Context {
+	if mode == runTxModeSimulate {
+		ctx = ctx.WithMultiStore(getState(app, runTxModeSimulate).CacheMultiStore())
+	}
+	return ctx
+}
+
 // runTx processes a transaction. The transactions is proccessed via an
 // anteHandler. txBytes may be nil in some cases, eg. in tests. Also, in the
 // future we may support "internal" transactions.
@@ -575,7 +581,9 @@ func (app *BaseApp) runTx(mode runTxMode, txBytes []byte, tx sdk.Tx) (result sdk
 	// determined by the GasMeter. We need access to the context to get the gas
 	// meter so we initialize upfront.
 	var gasWanted int64
+	var msCache sdk.CacheMultiStore
 	ctx := app.getContextForAnte(mode, txBytes)
+	ctx = app.initializeContext(ctx, mode)
 
 	defer func() {
 		if r := recover(); r != nil {
@@ -594,15 +602,13 @@ func (app *BaseApp) runTx(mode runTxMode, txBytes []byte, tx sdk.Tx) (result sdk
 	}()
 
 	var msgs = tx.GetMsgs()
-
-	err := validateBasicTxMsgs(msgs)
-	if err != nil {
+	if err := validateBasicTxMsgs(msgs); err != nil {
 		return err.Result()
 	}
 
 	// run the ante handler
 	if app.anteHandler != nil {
-		newCtx, result, abort := app.anteHandler(ctx, tx)
+		newCtx, result, abort := app.anteHandler(ctx, tx, (mode == runTxModeSimulate))
 		if abort {
 			return result
 		}
@@ -613,9 +619,15 @@ func (app *BaseApp) runTx(mode runTxMode, txBytes []byte, tx sdk.Tx) (result sdk
 		gasWanted = result.GasWanted
 	}
 
+	if mode == runTxModeSimulate {
+		result = app.runMsgs(ctx, msgs, mode)
+		result.GasWanted = gasWanted
+		return
+	}
+
 	// Keep the state in a transient CacheWrap in case processing the messages
 	// fails.
-	msCache := getState(app, mode).CacheMultiStore()
+	msCache = getState(app, mode).CacheMultiStore()
 	if msCache.TracingEnabled() {
 		msCache = msCache.WithTracingContext(sdk.TraceContext(
 			map[string]interface{}{"txHash": cmn.HexBytes(tmhash.Sum(txBytes)).String()},
@@ -626,8 +638,8 @@ func (app *BaseApp) runTx(mode runTxMode, txBytes []byte, tx sdk.Tx) (result sdk
 	result = app.runMsgs(ctx, msgs, mode)
 	result.GasWanted = gasWanted
 
-	// only update state if all messages pass and we're not in a simulation
-	if result.IsOK() && mode != runTxModeSimulate {
+	// only update state if all messages pass
+	if result.IsOK() {
 		msCache.Write()
 	}
 

baseapp/baseapp_test.go

@@ -365,7 +365,7 @@ func testTxDecoder(cdc *wire.Codec) sdk.TxDecoder {
 }
 
 func anteHandlerTxTest(t *testing.T, capKey *sdk.KVStoreKey, storeKey []byte) sdk.AnteHandler {
-	return func(ctx sdk.Context, tx sdk.Tx) (newCtx sdk.Context, res sdk.Result, abort bool) {
+	return func(ctx sdk.Context, tx sdk.Tx, simulate bool) (newCtx sdk.Context, res sdk.Result, abort bool) {
 		store := ctx.KVStore(capKey)
 		msgCounter := tx.(txTest).Counter
 		res = incrementingCounter(t, store, storeKey, msgCounter)
@@ -595,7 +595,7 @@ func TestSimulateTx(t *testing.T) {
 	gasConsumed := int64(5)
 
 	anteOpt := func(bapp *BaseApp) {
-		bapp.SetAnteHandler(func(ctx sdk.Context, tx sdk.Tx) (newCtx sdk.Context, res sdk.Result, abort bool) {
+		bapp.SetAnteHandler(func(ctx sdk.Context, tx sdk.Tx, simulate bool) (newCtx sdk.Context, res sdk.Result, abort bool) {
 			newCtx = ctx.WithGasMeter(sdk.NewGasMeter(gasConsumed))
 			return
 		})
@@ -659,7 +659,9 @@ func TestSimulateTx(t *testing.T) {
 
 func TestRunInvalidTransaction(t *testing.T) {
 	anteOpt := func(bapp *BaseApp) {
-		bapp.SetAnteHandler(func(ctx sdk.Context, tx sdk.Tx) (newCtx sdk.Context, res sdk.Result, abort bool) { return })
+		bapp.SetAnteHandler(func(ctx sdk.Context, tx sdk.Tx, simulate bool) (newCtx sdk.Context, res sdk.Result, abort bool) {
+			return
+		})
 	}
 	routerOpt := func(bapp *BaseApp) {
 		bapp.Router().AddRoute(typeMsgCounter, func(ctx sdk.Context, msg sdk.Msg) (res sdk.Result) { return })
@@ -734,7 +736,7 @@ func TestRunInvalidTransaction(t *testing.T) {
 func TestTxGasLimits(t *testing.T) {
 	gasGranted := int64(10)
 	anteOpt := func(bapp *BaseApp) {
-		bapp.SetAnteHandler(func(ctx sdk.Context, tx sdk.Tx) (newCtx sdk.Context, res sdk.Result, abort bool) {
+		bapp.SetAnteHandler(func(ctx sdk.Context, tx sdk.Tx, simulate bool) (newCtx sdk.Context, res sdk.Result, abort bool) {
 			newCtx = ctx.WithGasMeter(sdk.NewGasMeter(gasGranted))
 
 			// NOTE/TODO/XXX:
@@ -825,7 +827,7 @@ func TestTxGasLimits(t *testing.T) {
 func TestQuery(t *testing.T) {
 	key, value := []byte("hello"), []byte("goodbye")
 	anteOpt := func(bapp *BaseApp) {
-		bapp.SetAnteHandler(func(ctx sdk.Context, tx sdk.Tx) (newCtx sdk.Context, res sdk.Result, abort bool) {
+		bapp.SetAnteHandler(func(ctx sdk.Context, tx sdk.Tx, simulate bool) (newCtx sdk.Context, res sdk.Result, abort bool) {
 			store := ctx.KVStore(capKey1)
 			store.Set(key, value)
 			return

client/context/context.go

@@ -22,6 +22,8 @@ type CLIContext struct {
 	Client          rpcclient.Client
 	Logger          io.Writer
 	Height          int64
+	Gas             int64
+	GasAdjustment   float64
 	NodeURI         string
 	FromAddressName string
 	AccountStore    string
@@ -48,6 +50,8 @@ func NewCLIContext() CLIContext {
 		AccountStore:    ctxAccStoreName,
 		FromAddressName: viper.GetString(client.FlagFrom),
 		Height:          viper.GetInt64(client.FlagHeight),
+		Gas:             viper.GetInt64(client.FlagGas),
+		GasAdjustment:   viper.GetFloat64(client.FlagGasAdjustment),
 		TrustNode:       viper.GetBool(client.FlagTrustNode),
 		UseLedger:       viper.GetBool(client.FlagUseLedger),
 		Async:           viper.GetBool(client.FlagAsync),

client/context/query.go

@@ -10,7 +10,6 @@ import (
 
 	"github.com/pkg/errors"
 
-	"github.com/tendermint/tendermint/libs/common"
 	cmn "github.com/tendermint/tendermint/libs/common"
 	rpcclient "github.com/tendermint/tendermint/rpc/client"
 	ctypes "github.com/tendermint/tendermint/rpc/core/types"
@@ -27,8 +26,8 @@ func (ctx CLIContext) GetNode() (rpcclient.Client, error) {
 }
 
 // Query performs a query for information about the connected node.
-func (ctx CLIContext) Query(path string) (res []byte, err error) {
-	return ctx.query(path, nil)
+func (ctx CLIContext) Query(path string, data cmn.HexBytes) (res []byte, err error) {
+	return ctx.query(path, data)
 }
 
 // Query information about the connected node with a data payload
@@ -284,7 +283,7 @@ func (ctx CLIContext) ensureBroadcastTx(txBytes []byte) error {
 
 // query performs a query from a Tendermint node with the provided store name
 // and path.
-func (ctx CLIContext) query(path string, key common.HexBytes) (res []byte, err error) {
+func (ctx CLIContext) query(path string, key cmn.HexBytes) (res []byte, err error) {
 	node, err := ctx.GetNode()
 	if err != nil {
 		return res, err

client/flags.go

@@ -4,11 +4,15 @@ import "github.com/spf13/cobra"
 
 // nolint
 const (
+	DefaultGasLimit      = 200000
+	DefaultGasAdjustment = 1.2
+
 	FlagUseLedger     = "ledger"
 	FlagChainID       = "chain-id"
 	FlagNode          = "node"
 	FlagHeight        = "height"
 	FlagGas           = "gas"
+	FlagGasAdjustment = "gas-adjustment"
 	FlagTrustNode     = "trust-node"
 	FlagFrom          = "from"
 	FlagName          = "name"
@@ -49,7 +53,8 @@ func PostCommands(cmds ...*cobra.Command) []*cobra.Command {
 		c.Flags().String(FlagChainID, "", "Chain ID of tendermint node")
 		c.Flags().String(FlagNode, "tcp://localhost:26657", "<host>:<port> to tendermint rpc interface for this chain")
 		c.Flags().Bool(FlagUseLedger, false, "Use a connected Ledger device")
-		c.Flags().Int64(FlagGas, 200000, "gas limit to set per-transaction")
+		c.Flags().Int64(FlagGas, DefaultGasLimit, "gas limit to set per-transaction; set to 0 to calculate required gas automatically")
+		c.Flags().Float64(FlagGasAdjustment, DefaultGasAdjustment, "adjustment factor to be multiplied against the estimate returned by the tx simulation")
 		c.Flags().Bool(FlagAsync, false, "broadcast transactions asynchronously")
 		c.Flags().Bool(FlagJson, false, "return output in json format")
 		c.Flags().Bool(FlagPrintResponse, true, "return tx response (only works with async = false)")

client/lcd/lcd_test.go

@@ -263,6 +263,14 @@ func TestCoinSend(t *testing.T) {
 
 	require.Equal(t, "steak", mycoins.Denom)
 	require.Equal(t, int64(1), mycoins.Amount.Int64())
+
+	// test failure with too little gas
+	res, body, _ = doSendWithGas(t, port, seed, name, password, addr, 100)
+	require.Equal(t, http.StatusInternalServerError, res.StatusCode, body)
+
+	// test success with just enough gas
+	res, body, _ = doSendWithGas(t, port, seed, name, password, addr, 3000)
+	require.Equal(t, http.StatusOK, res.StatusCode, body)
 }
 
 func TestIBCTransfer(t *testing.T) {
@@ -712,7 +720,7 @@ func getAccount(t *testing.T, port string, addr sdk.AccAddress) auth.Account {
 	return acc
 }
 
-func doSend(t *testing.T, port, seed, name, password string, addr sdk.AccAddress) (receiveAddr sdk.AccAddress, resultTx ctypes.ResultBroadcastTxCommit) {
+func doSendWithGas(t *testing.T, port, seed, name, password string, addr sdk.AccAddress, gas int64) (res *http.Response, body string, receiveAddr sdk.AccAddress) {
 
 	// create receive address
 	kb := client.MockKeyBase()
@@ -730,19 +738,31 @@ func doSend(t *testing.T, port, seed, name, password string, addr sdk.AccAddress
 		panic(err)
 	}
 
+	gasStr := ""
+	if gas > 0 {
+		gasStr = fmt.Sprintf(`
+		"gas":"%v",
+		`, gas)
+	}
 	jsonStr := []byte(fmt.Sprintf(`{
+		%v
 		"name":"%s",
 		"password":"%s",
 		"account_number":"%d",
 		"sequence":"%d",
-		"gas": "10000",
 		"amount":[%s],
 		"chain_id":"%s"
-	}`, name, password, accnum, sequence, coinbz, chainID))
-	res, body := Request(t, port, "POST", fmt.Sprintf("/accounts/%s/send", receiveAddr), jsonStr)
+	}`, gasStr, name, password, accnum, sequence, coinbz, chainID))
+
+	res, body = Request(t, port, "POST", fmt.Sprintf("/accounts/%s/send", receiveAddr), jsonStr)
+	return
+}
+
+func doSend(t *testing.T, port, seed, name, password string, addr sdk.AccAddress) (receiveAddr sdk.AccAddress, resultTx ctypes.ResultBroadcastTxCommit) {
+	res, body, receiveAddr := doSendWithGas(t, port, seed, name, password, addr, 0)
 	require.Equal(t, http.StatusOK, res.StatusCode, body)
 
-	err = cdc.UnmarshalJSON([]byte(body), &resultTx)
+	err := cdc.UnmarshalJSON([]byte(body), &resultTx)
 	require.Nil(t, err)
 
 	return receiveAddr, resultTx
@@ -768,7 +788,6 @@ func doIBCTransfer(t *testing.T, port, seed, name, password string, addr sdk.Acc
 		"password": "%s",
 		"account_number":"%d",
 		"sequence": "%d",
-		"gas": "100000",
 		"src_chain_id": "%s",
 		"amount":[
 			{
@@ -887,7 +906,6 @@ func doDelegate(t *testing.T, port, seed, name, password string, delegatorAddr,
 		"password": "%s",
 		"account_number": "%d",
 		"sequence": "%d",
-		"gas": "10000",
 		"chain_id": "%s",
 		"delegations": [
 			{
@@ -925,7 +943,6 @@ func doBeginUnbonding(t *testing.T, port, seed, name, password string,
 		"password": "%s",
 		"account_number": "%d",
 		"sequence": "%d",
-		"gas": "20000",
 		"chain_id": "%s",
 		"delegations": [],
 		"begin_unbondings": [
@@ -964,7 +981,6 @@ func doBeginRedelegation(t *testing.T, port, seed, name, password string,
 		"password": "%s",
 		"account_number": "%d",
 		"sequence": "%d",
-		"gas": "10000",
 		"chain_id": "%s",
 		"delegations": [],
 		"begin_unbondings": [],
@@ -1116,8 +1132,7 @@ func doSubmitProposal(t *testing.T, port, seed, name, password string, proposerA
 			"password": "%s",
 			"chain_id": "%s",
 			"account_number":"%d",
-			"sequence":"%d",
-			"gas":"100000"
+			"sequence":"%d"
 		}
 	}`, proposerAddr, name, password, chainID, accnum, sequence))
 	res, body := Request(t, port, "POST", "/gov/proposals", jsonStr)
@@ -1147,8 +1162,7 @@ func doDeposit(t *testing.T, port, seed, name, password string, proposerAddr sdk
 			"password": "%s",
 			"chain_id": "%s",
 			"account_number":"%d",
-			"sequence": "%d",
-			"gas":"100000"
+			"sequence": "%d"
 		}
 	}`, proposerAddr, name, password, chainID, accnum, sequence))
 	res, body := Request(t, port, "POST", fmt.Sprintf("/gov/proposals/%d/deposits", proposalID), jsonStr)
@@ -1178,8 +1192,7 @@ func doVote(t *testing.T, port, seed, name, password string, proposerAddr sdk.Ac
 			"password": "%s",
 			"chain_id": "%s",
 			"account_number": "%d",
-			"sequence": "%d",
-			"gas":"100000"
+			"sequence": "%d"
 		}
 	}`, proposerAddr, name, password, chainID, accnum, sequence))
 	res, body := Request(t, port, "POST", fmt.Sprintf("/gov/proposals/%d/votes", proposalID), jsonStr)

client/lcd/version.go

@@ -17,7 +17,7 @@ func CLIVersionRequestHandler(w http.ResponseWriter, r *http.Request) {
 // connected node version REST handler endpoint
 func NodeVersionRequestHandler(cliCtx context.CLIContext) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
-		version, err := cliCtx.Query("/app/version")
+		version, err := cliCtx.Query("/app/version", nil)
 		if err != nil {
 			w.WriteHeader(http.StatusInternalServerError)
 			w.Write([]byte(fmt.Sprintf("Could't query version. Error: %s", err.Error())))

client/utils/rest.go

@@ -0,0 +1,12 @@
+package utils
+
+import (
+	"net/http"
+)
+
+// WriteErrorResponse prepares and writes a HTTP error
+// given a status code and an error message.
+func WriteErrorResponse(w *http.ResponseWriter, status int, msg string) {
+	(*w).WriteHeader(status)
+	(*w).Write([]byte(msg))
+}