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 +493,15 @@ 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 = ctx.WithSigningValidators(app.signedValidators)
+	ctx = getState(app, mode).ctx.WithTxBytes(txBytes)
+	if mode != runTxModeDeliver {
+		return
 	}
-
+	ctx = ctx.WithSigningValidators(app.signedValidators)
 	return
 }
 
@@ -567,6 +567,13 @@ func getState(app *BaseApp, mode runTxMode) *state {
 	return app.deliverState
 }
 
+func (app *BaseApp) initializeContext(ctx sdk.Context, mode runTxMode) sdk.Context {
+	if mode != runTxModeSimulate {
+		return ctx
+	}
+	return ctx.WithMultiStore(getState(app, runTxModeSimulate).CacheMultiStore())
+}
+
 // 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 +582,9 @@ 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 {
@@ -594,9 +603,7 @@ 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()
 	}
 
@@ -613,9 +620,15 @@ 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 +639,8 @@ 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()
 	}
 

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 +4,14 @@ import "github.com/spf13/cobra"
 
 // nolint
 const (
+	DefaultGasAdjustment = 0
+
 	FlagUseLedger     = "ledger"
 	FlagChainID       = "chain-id"
 	FlagNode          = "node"
 	FlagHeight        = "height"
 	FlagGas           = "gas"
+	FlagGasAdjustment = "gas-adjustment"
 	FlagTrustNode     = "trust-node"
 	FlagFrom          = "from"
 	FlagName          = "name"
@@ -49,7 +52,8 @@ 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, 0, "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; defaults to an internal value")
 		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))
+}