Goal: Introduce new command for simulate

cmd/goal/application.go

@@ -1063,7 +1063,7 @@ var infoAppCmd = &cobra.Command{
 }
 
 // populateMethodCallTxnArgs parses and loads transactions from the files indicated by the values
-// slice. An error will occur if the transaction does not matched the expected type, it has a nonzero
+// slice. An error will occur if the transaction does not match the expected type, it has a nonzero
 // group ID, or if it is signed by a normal signature or Msig signature (but not Lsig signature)
 func populateMethodCallTxnArgs(types []string, values []string) ([]transactions.SignedTxn, error) {
 	loadedTxns := make([]transactions.SignedTxn, len(values))

cmd/goal/clerk.go

@@ -76,6 +76,7 @@ func init() {
 	clerkCmd.AddCommand(compileCmd)
 	clerkCmd.AddCommand(dryrunCmd)
 	clerkCmd.AddCommand(dryrunRemoteCmd)
+	clerkCmd.AddCommand(simulateCmd)
 
 	// Wallet to be used for the clerk operation
 	clerkCmd.PersistentFlags().StringVarP(&walletName, "wallet", "w", "", "Set the wallet to be used for the selected operation")
@@ -88,7 +89,7 @@ func init() {
 	sendCmd.Flags().StringVar(&rekeyToAddress, "rekey-to", "", "Rekey account to the given spending key/address. (Future transactions from this account will need to be signed with the new key.)")
 	sendCmd.Flags().StringVarP(&programSource, "from-program", "F", "", "Program source to use as account logic")
 	sendCmd.Flags().StringVarP(&progByteFile, "from-program-bytes", "P", "", "Program binary to use as account logic")
-	sendCmd.Flags().StringSliceVar(&argB64Strings, "argb64", nil, "base64 encoded args to pass to transaction logic")
+	sendCmd.Flags().StringSliceVar(&argB64Strings, "argb64", nil, "Base64 encoded args to pass to transaction logic")
 	sendCmd.Flags().StringVarP(&logicSigFile, "logic-sig", "L", "", "LogicSig to apply to transaction")
 	sendCmd.Flags().StringVar(&msigParams, "msig-params", "", "Multisig preimage parameters - [threshold] [Address 1] [Address 2] ...\nUsed to add the necessary fields in case the account was rekeyed to a multisig account")
 	sendCmd.MarkFlagRequired("to")
@@ -108,8 +109,8 @@ func init() {
 	signCmd.Flags().StringVarP(&signerAddress, "signer", "S", "", "Address of key to sign with, if different from transaction \"from\" address due to rekeying")
 	signCmd.Flags().StringVarP(&programSource, "program", "p", "", "Program source to use as account logic")
 	signCmd.Flags().StringVarP(&logicSigFile, "logic-sig", "L", "", "LogicSig to apply to transaction")
-	signCmd.Flags().StringSliceVar(&argB64Strings, "argb64", nil, "base64 encoded args to pass to transaction logic")
-	signCmd.Flags().StringVarP(&protoVersion, "proto", "P", "", "consensus protocol version id string")
+	signCmd.Flags().StringSliceVar(&argB64Strings, "argb64", nil, "Base64 encoded args to pass to transaction logic")
+	signCmd.Flags().StringVarP(&protoVersion, "proto", "P", "", "Consensus protocol version id string")
 	signCmd.MarkFlagRequired("infile")
 	signCmd.MarkFlagRequired("outfile")
 
@@ -123,26 +124,29 @@ func init() {
 	splitCmd.MarkFlagRequired("infile")
 	splitCmd.MarkFlagRequired("outfile")
 
-	compileCmd.Flags().BoolVarP(&disassemble, "disassemble", "D", false, "disassemble a compiled program")
-	compileCmd.Flags().BoolVarP(&noProgramOutput, "no-out", "n", false, "don't write contract program binary")
-	compileCmd.Flags().BoolVarP(&writeSourceMap, "map", "m", false, "write out source map")
-	compileCmd.Flags().BoolVarP(&signProgram, "sign", "s", false, "sign program, output is a binary signed LogicSig record")
+	compileCmd.Flags().BoolVarP(&disassemble, "disassemble", "D", false, "Disassemble a compiled program")
+	compileCmd.Flags().BoolVarP(&noProgramOutput, "no-out", "n", false, "Don't write contract program binary")
+	compileCmd.Flags().BoolVarP(&writeSourceMap, "map", "m", false, "Write out source map")
+	compileCmd.Flags().BoolVarP(&signProgram, "sign", "s", false, "Sign program, output is a binary signed LogicSig record")
 	compileCmd.Flags().StringVarP(&outFilename, "outfile", "o", "", "Filename to write program bytes or signed LogicSig to")
 	compileCmd.Flags().StringVarP(&account, "account", "a", "", "Account address to sign the program (If not specified, uses default account)")
 
-	dryrunCmd.Flags().StringVarP(&txFilename, "txfile", "t", "", "transaction or transaction-group to test")
-	dryrunCmd.Flags().StringVarP(&protoVersion, "proto", "P", "", "consensus protocol version id string")
+	dryrunCmd.Flags().StringVarP(&txFilename, "txfile", "t", "", "Transaction or transaction-group to test")
+	dryrunCmd.Flags().StringVarP(&protoVersion, "proto", "P", "", "Consensus protocol version id string")
 	dryrunCmd.Flags().BoolVar(&dumpForDryrun, "dryrun-dump", false, "Dump in dryrun format acceptable by dryrun REST api instead of running")
 	dryrunCmd.Flags().Var(&dumpForDryrunFormat, "dryrun-dump-format", "Dryrun dump format: "+dumpForDryrunFormat.AllowedString())
-	dryrunCmd.Flags().StringSliceVar(&dumpForDryrunAccts, "dryrun-accounts", nil, "additional accounts to include into dryrun request obj")
+	dryrunCmd.Flags().StringSliceVar(&dumpForDryrunAccts, "dryrun-accounts", nil, "Additional accounts to include into dryrun request obj")
 	dryrunCmd.Flags().StringVarP(&outFilename, "outfile", "o", "", "Filename for writing dryrun state object")
 	dryrunCmd.MarkFlagRequired("txfile")
 
-	dryrunRemoteCmd.Flags().StringVarP(&txFilename, "dryrun-state", "D", "", "dryrun request object to run")
-	dryrunRemoteCmd.Flags().BoolVarP(&verbose, "verbose", "v", false, "print more info")
-	dryrunRemoteCmd.Flags().BoolVarP(&rawOutput, "raw", "r", false, "output raw response from algod")
+	dryrunRemoteCmd.Flags().StringVarP(&txFilename, "dryrun-state", "D", "", "Dryrun request object to run")
+	dryrunRemoteCmd.Flags().BoolVarP(&verbose, "verbose", "v", false, "Print more info")
+	dryrunRemoteCmd.Flags().BoolVarP(&rawOutput, "raw", "r", false, "Output raw response from algod")
 	dryrunRemoteCmd.MarkFlagRequired("dryrun-state")
 
+	simulateCmd.Flags().StringVarP(&txFilename, "txfile", "t", "", "Transaction or transaction-group to test")
+	simulateCmd.Flags().StringVarP(&outFilename, "outfile", "o", "", "Filename for writing simulation result")
+	panicIfErr(simulateCmd.MarkFlagRequired("txfile"))
 }
 
 var clerkCmd = &cobra.Command{
@@ -1253,6 +1257,34 @@ var dryrunRemoteCmd = &cobra.Command{
 	},
 }
 
+var simulateCmd = &cobra.Command{
+	Use:   "simulate",
+	Short: "Simulate a transaction or transaction group offline",
+	Long:  `Simulate a transaction or transaction group offline under various conditions and verbosity.`,
+	Run: func(cmd *cobra.Command, args []string) {
+		data, err := readFile(txFilename)
+		if err != nil {
+			reportErrorf(fileReadError, txFilename, err)
+		}
+
+		dataDir := datadir.EnsureSingleDataDir()
+		client := ensureFullClient(dataDir)
+		resp, err := client.TransactionSimulation(data)
+		if err != nil {
+			reportErrorf("simulation error: %s", err.Error())
+		}
+
+		if outFilename != "" {
+			err = writeFile(outFilename, protocol.EncodeJSON(&resp), 0600)
+			if err != nil {
+				reportErrorf("write file error: %s", err.Error())
+			}
+		} else {
+			fmt.Println(string(protocol.EncodeJSON(&resp)))
+		}
+	},
+}
+
 // unmarshalSlice converts string addresses to basics.Address
 func unmarshalSlice(accts []string) ([]basics.Address, error) {
 	result := make([]basics.Address, 0, len(accts))

daemon/algod/api/client/restClient.go

@@ -45,10 +45,11 @@ const (
 
 // rawRequestPaths is a set of paths where the body should not be urlencoded
 var rawRequestPaths = map[string]bool{
-	"/v2/transactions":  true,
-	"/v2/teal/dryrun":   true,
-	"/v2/teal/compile":  true,
-	"/v2/participation": true,
+	"/v2/transactions":          true,
+	"/v2/teal/dryrun":           true,
+	"/v2/teal/compile":          true,
+	"/v2/participation":         true,
+	"/v2/transactions/simulate": true,
 }
 
 // unauthorizedRequestError is generated when we receive 401 error from the server. This error includes the inner error
@@ -284,7 +285,7 @@ func (client RestClient) WaitForBlock(round basics.Round) (response model.NodeSt
 	return
 }
 
-// HealthCheck does a health check on the the potentially running node,
+// HealthCheck does a health check on the potentially running node,
 // returning an error if the API is down
 func (client RestClient) HealthCheck() error {
 	return client.get(nil, "/health", nil)
@@ -629,6 +630,12 @@ func (client RestClient) RawDryrun(data []byte) (response []byte, err error) {
 	return
 }
 
+// RawTransactionSimulate gets the raw transaction or raw transaction group, and returns relevant simulation results.
+func (client RestClient) RawTransactionSimulate(data []byte) (response model.SimulateResponse, err error) {
+	err = client.submitForm(&response, "/v2/transactions/simulate", data, "POST", false /* encodeJSON */, true /* decodeJSON */, false)
+	return
+}
+
 // StateProofs gets a state proof that covers a given round
 func (client RestClient) StateProofs(round uint64) (response model.StateProofResponse, err error) {
 	err = client.get(&response, fmt.Sprintf("/v2/stateproofs/%d", round), nil)
@@ -670,7 +677,6 @@ func (client RestClient) GetParticipationKeyByID(participationID string) (respon
 func (client RestClient) RemoveParticipationKeyByID(participationID string) (err error) {
 	err = client.delete(nil, fmt.Sprintf("/v2/participation/%s", participationID), nil, true)
 	return
-
 }
 
 /* Endpoint registered for follower nodes */

libgoal/libgoal.go

@@ -504,11 +504,10 @@ func (c *Client) signAndBroadcastTransactionWithWallet(walletHandle, pw []byte,
 //
 // validRounds | lastValid | result (lastValid)
 // -------------------------------------------------
-// 	  	 0     |     0     | firstValid + maxTxnLife
-// 		 0     |     N     | lastValid
-// 		 M     |     0     | first + validRounds - 1
-// 		 M     |     M     | error
-//
+// 0           |     0     | firstValid + maxTxnLife
+// 0           |     N     | lastValid
+// M           |     0     | first + validRounds - 1
+// M           |     M     | error
 func (c *Client) ComputeValidityRounds(firstValid, lastValid, validRounds uint64) (first, last, latest uint64, err error) {
 	params, err := c.cachedSuggestedParams()
 	if err != nil {
@@ -1270,6 +1269,16 @@ func (c *Client) Dryrun(data []byte) (resp model.DryrunResponse, err error) {
 	return
 }
 
+// TransactionSimulation takes raw transaction or raw transaction group, and returns relevant simulation results.
+func (c *Client) TransactionSimulation(data []byte) (resp model.SimulateResponse, err error) {
+	algod, err := c.ensureAlgodClient()
+	if err != nil {
+		return
+	}
+	resp, err = algod.RawTransactionSimulate(data)
+	return
+}
+
 // TransactionProof returns a Merkle proof for a transaction in a block.
 func (c *Client) TransactionProof(txid string, round uint64, hashType crypto.HashType) (resp model.TransactionProofResponse, err error) {
 	algod, err := c.ensureAlgodClient()

test/scripts/e2e_subs/e2e-app-simulate.sh

@@ -0,0 +1,93 @@
+#!/bin/bash
+
+date '+app-simple-test start %Y%m%d_%H%M%S'
+
+set -e
+set -x
+set -o pipefail
+set -o nounset
+export SHELLOPTS
+
+WALLET=$1
+
+# Directory of this bash program
+DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
+
+gcmd="goal -w ${WALLET}"
+
+ACCOUNT=$(${gcmd} account list|awk '{ print $3 }')
+
+CONST_TRUE="true"
+CONST_FALSE="false"
+
+${gcmd} clerk send -a 10000 -f ${ACCOUNT} -t ${ACCOUNT} -o pay1.tx
+${gcmd} clerk send -a 10000 -f ${ACCOUNT} -t ${ACCOUNT} -o pay2.tx
+
+cat pay1.tx pay2.tx | ${gcmd} clerk group -i - -o grouped.tx
+
+# We first test transaction group simulation WITHOUT signatures
+RES=$(${gcmd} clerk simulate -t grouped.tx | jq '."would-succeed"')
+
+if [[ $RES != $CONST_FALSE ]]; then
+    date '+app-simulate-test FAIL the simulation transaction group without signatures should not succeed %Y%m%d_%H%M%S'
+    false
+fi
+
+# We then test transaction group simulation WITH signatures
+${gcmd} clerk split -i grouped.tx -o grouped.tx
+
+${gcmd} clerk sign -i grouped-0.tx -o grouped-0.stx
+${gcmd} clerk sign -i grouped-1.tx -o grouped-1.stx
+
+cat grouped-0.stx grouped-1.stx > grouped.stx
+
+RES=$(${gcmd} clerk simulate -t grouped.stx | jq '."would-succeed"')
+
+if [[ $RES != $CONST_TRUE ]]; then
+    date '+app-simulate-test FAIL should pass to simulate self pay transaction group %Y%m%d_%H%M%S'
+    false
+fi
+
+#######################################################
+# NOW WE TRY TO TEST SIMULATION WITH ABI METHOD CALLS #
+#######################################################
+
+printf '#pragma version 2\nint 1' > "${TEMPDIR}/simple-v2.teal"
+
+# Real Create
+RES=$(${gcmd} app method --method "create(uint64)uint64" --arg "1234" --create --approval-prog ${DIR}/tealprogs/app-abi-method-example.teal --clear-prog ${TEMPDIR}/simple-v2.teal --global-byteslices 0 --global-ints 0 --local-byteslices 1 --local-ints 0 --extra-pages 0 --from $ACCOUNT 2>&1 || true)
+EXPECTED="method create(uint64)uint64 succeeded with output: 2468"
+if [[ $RES != *"${EXPECTED}"* ]]; then
+    date '+app-simulate-test FAIL the method call to create(uint64)uint64 should not fail %Y%m%d_%H%M%S'
+    false
+fi
+
+APPID=$(echo "$RES" | grep Created | awk '{ print $6 }')
+
+# SIMULATION! empty()void
+${gcmd} app method --method "empty()void" --app-id $APPID --from $ACCOUNT 2>&1 -o empty.tx
+
+# SIMULATE without a signature first
+RES=$(${gcmd} clerk simulate -t empty.tx)
+
+# confirm that without signature, the simulation should fail
+if [[ $(echo "$RES" | jq '."would-succeed"') != $CONST_FALSE ]]; then
+    date '+app-simulate-test FAIL the simulation call to empty()void without signature should not succeed %Y%m%d_%H%M%S'
+    false
+fi
+
+# check again the simulation failing reason
+if [[ $(echo "$RES" | jq '."txn-groups"[0]."txn-results"[0]."missing-signature"') != $CONST_TRUE ]]; then
+    date '+app-simulate-test FAIL the simulation call to empty()void without signature should fail with missing-signature %Y%m%d_%H%M%S'
+    false
+fi
+
+# SIMULATE with a signature
+${gcmd} clerk sign -i empty.tx -o empty.stx
+RES=$(${gcmd} clerk simulate -t empty.stx | jq '."would-succeed"')
+
+# with signature, simulation app-call should succeed
+if [[ $RES != $CONST_TRUE ]]; then
+    date '+app-simulate-test FAIL the simulation call to empty()void should succeed %Y%m%d_%H%M%S'
+    false
+fi