Add support for configurable transaction messages

faucet.go

@@ -30,9 +30,10 @@ type Faucet struct {
 
 	mux *chi.Mux // HTTP routing
 
-	config      *config.Config // faucet configuration
-	middlewares []Middleware   // request middlewares
-	handlers    []Handler      // request handlers
+	config         *config.Config     // faucet configuration
+	middlewares    []Middleware       // request middlewares
+	handlers       []Handler          // request handlers
+	prepareTxMsgFn PrepareTxMessageFn // transaction message creator
 
 	sendAmount std.Coins // for fast lookup
 }
@@ -44,11 +45,12 @@ func NewFaucet(
 	opts ...Option,
 ) (*Faucet, error) {
 	f := &Faucet{
-		estimator:   estimator,
-		client:      client,
-		logger:      noop.New(),
-		config:      config.DefaultConfig(),
-		middlewares: nil, // no middlewares by default
+		estimator:      estimator,
+		client:         client,
+		logger:         noop.New(),
+		config:         config.DefaultConfig(),
+		prepareTxMsgFn: defaultPrepareTxMessage,
+		middlewares:    nil, // no middlewares by default
 
 		mux: chi.NewMux(),
 	}

faucet_test.go

@@ -6,6 +6,9 @@ import (
 
 	"github.com/gnolang/faucet/config"
 	"github.com/gnolang/faucet/log/noop"
+	"github.com/gnolang/gno/gno.land/pkg/sdk/vm"
+	"github.com/gnolang/gno/tm2/pkg/crypto"
+	"github.com/gnolang/gno/tm2/pkg/std"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
@@ -138,4 +141,52 @@ func TestFaucet_NewFaucet(t *testing.T) {
 		assert.NotNil(t, f)
 		assert.NoError(t, err)
 	})
+
+	t.Run("with prepare transaction message callback", func(t *testing.T) {
+		t.Parallel()
+
+		var (
+			cfg = PrepareCfg{
+				SendAmount:  std.NewCoins(std.NewCoin("ugnot", 10)),
+				FromAddress: crypto.Address{1},
+				ToAddress:   crypto.Address{2},
+			}
+
+			pkgPath = "gno.land/r/demo/example"
+			pkgFunc = "FundPlayer"
+
+			prepareTxMsgFn = func(cfg PrepareCfg) std.Msg {
+				return vm.MsgCall{
+					Caller:  cfg.FromAddress,
+					PkgPath: pkgPath,
+					Func:    pkgFunc,
+					Args:    []string{cfg.ToAddress.String()},
+					Send:    cfg.SendAmount,
+				}
+			}
+		)
+
+		f, err := NewFaucet(
+			&mockEstimator{},
+			&mockClient{},
+			WithConfig(config.DefaultConfig()),
+			WithPrepareTxMessageFn(prepareTxMsgFn),
+		)
+
+		require.NotNil(t, f)
+		require.NoError(t, err)
+
+		// Prepare the message
+		msg := f.prepareTxMsgFn(cfg)
+
+		// Validate the message
+		msgCall, ok := msg.(vm.MsgCall)
+		require.True(t, ok)
+
+		assert.Equal(t, cfg.FromAddress, msgCall.Caller)
+		assert.Equal(t, pkgPath, msgCall.PkgPath)
+		assert.Equal(t, pkgFunc, msgCall.Func)
+		assert.Equal(t, []string{cfg.ToAddress.String()}, msgCall.Args)
+		assert.Equal(t, cfg.SendAmount, msgCall.Send)
+	})
 }

go.mod

@@ -18,6 +18,7 @@ require (
 	github.com/btcsuite/btcd/btcutil v1.0.0 // indirect
 	github.com/cespare/xxhash v1.1.0 // indirect
 	github.com/cespare/xxhash/v2 v2.1.1 // indirect
+	github.com/cockroachdb/apd v1.1.0 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/dgraph-io/badger/v3 v3.2103.4 // indirect
 	github.com/dgraph-io/ristretto v0.1.1 // indirect
@@ -45,6 +46,7 @@ require (
 	golang.org/x/mod v0.12.0 // indirect
 	golang.org/x/net v0.15.0 // indirect
 	golang.org/x/sys v0.12.0 // indirect
+	golang.org/x/tools v0.6.0 // indirect
 	google.golang.org/protobuf v1.31.0 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -22,6 +22,8 @@ github.com/cespare/xxhash v1.1.0/go.mod h1:XrSqR1VqqWfGrhpAt58auRo0WTKS1nRRg3ghf
 github.com/cespare/xxhash/v2 v2.1.1 h1:6MnRN8NT7+YBpUIWxHtefFZOKTAPgGjpQSxqLNn0+qY=
 github.com/cespare/xxhash/v2 v2.1.1/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
 github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
+github.com/cockroachdb/apd v1.1.0 h1:3LFP3629v+1aKXU5Q37mxmRxX/pIu1nijXydLShEq5I=
+github.com/cockroachdb/apd v1.1.0/go.mod h1:8Sl8LxpKi29FqWXR16WEFZRNSz3SoPzUzeMeY4+DwBQ=
 github.com/coreos/etcd v3.3.10+incompatible/go.mod h1:uF7uidLiAD3TWHmW31ZFd/JWoc32PjwdhPthX9715RE=
 github.com/coreos/go-etcd v2.0.0+incompatible/go.mod h1:Jez6KQU2B/sWsbdaef3ED8NzMklzPG4d5KIOhIy30Tk=
 github.com/coreos/go-semver v0.2.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
@@ -94,6 +96,7 @@ github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORN
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
+github.com/lib/pq v1.10.7 h1:p7ZhMD+KsSRozJr34udlUrhboJwWAgCg34+/ZZNvZZw=
 github.com/libp2p/go-buffer-pool v0.1.0 h1:oK4mSFcQz7cTQIfqbe4MIj9gLW+mnanjyFtc6cdF0Y8=
 github.com/libp2p/go-buffer-pool v0.1.0/go.mod h1:N+vh8gMqimBzdKkSMVuydVDq+UV5QTWy5HSiZacSbPg=
 github.com/linxGnu/grocksdb v1.8.4 h1:ZMsBpPpJNtRLHiKKp0mI7gW+NT4s7UgfD5xHxx1jVRo=
@@ -203,6 +206,8 @@ golang.org/x/tools v0.0.0-20190311212946-11955173bddd/go.mod h1:LCzVGOaR6xXOjkQ3
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20200619180055-7c47624df98f/go.mod h1:EkVYQZoAsY45+roYkvgYkIh4xh/qjgUK9TdY2XT94GE=
 golang.org/x/tools v0.0.0-20210106214847-113979e3529a/go.mod h1:emZCQorbCU4vsT4fOWvOPXz4eW1wZW4PmDk9uLelYpA=
+golang.org/x/tools v0.6.0 h1:BOw41kyTf3PuCW1pVQf8+Cyg8pMlkYB1oo9iJ6D/lKM=
+golang.org/x/tools v0.6.0/go.mod h1:Xwgl3UAJ/d3gWutnCtw505GrjyAbvKui8lOU390QaIU=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

handler.go

@@ -74,7 +74,7 @@ func (f *Faucet) handleRequest(writer writer.ResponseWriter, requests Requests)
 			continue
 		}
 
-		// Run the method methodHandler
+		// Run the method handler
 		if err := f.transferFunds(beneficiary); err != nil {
 			f.logger.Debug(
 				unableToHandleRequest,

options.go

@@ -34,3 +34,11 @@ func WithHandlers(handlers []Handler) Option {
 		f.handlers = append(f.handlers, handlers...)
 	}
 }
+
+// WithPrepareTxMessageFn specifies the faucet
+// transaction message constructor
+func WithPrepareTxMessageFn(prepareTxMsgFn PrepareTxMessageFn) Option {
+	return func(f *Faucet) {
+		f.prepareTxMsgFn = prepareTxMsgFn
+	}
+}

prepare.go

@@ -7,28 +7,33 @@ import (
 	"github.com/gnolang/gno/tm2/pkg/std"
 )
 
-// prepareCfg specifies the tx prepare configuration
-type prepareCfg struct {
-	sendAmount  std.Coins      // the amount to be sent
-	fromAddress crypto.Address // the faucet address
-	toAddress   crypto.Address // the beneficiary address
+// PrepareTxMessageFn is the callback method that
+// constructs the faucet fund transaction message
+type PrepareTxMessageFn func(PrepareCfg) std.Msg
+
+// PrepareCfg specifies the tx prepare configuration
+type PrepareCfg struct {
+	SendAmount  std.Coins      // the amount to be sent
+	FromAddress crypto.Address // the faucet address
+	ToAddress   crypto.Address // the beneficiary address
+}
+
+// defaultPrepareTxMessage constructs the default
+// native currency transfer message
+func defaultPrepareTxMessage(cfg PrepareCfg) std.Msg {
+	return bank.MsgSend{
+		FromAddress: cfg.FromAddress,
+		ToAddress:   cfg.ToAddress,
+		Amount:      cfg.SendAmount,
+	}
 }
 
 // prepareTransaction prepares the transaction for signing
 func prepareTransaction(
 	estimator estimate.Estimator,
-	cfg prepareCfg,
+	msg std.Msg,
 ) *std.Tx {
 	// Construct the transaction
-	msg := vm.MsgCall{
-		FromAddress: cfg.fromAddress,
-		ToAddress:   cfg.toAddress,
-		PkgAddr: "gno.land/r/demo/chess/register",
-		Func: "RegisterPlayer",
-		Args: []string{"calleraddr", "token"},
-		Send:      cfg.sendAmount,
-	}
-
 	tx := &std.Tx{
 		Msgs:       []std.Msg{msg},
 		Signatures: nil,

prepare_test.go

@@ -36,13 +36,13 @@ func TestPrepareTransaction(t *testing.T) {
 	)
 
 	// Prepare the transaction
-	cfg := prepareCfg{
-		fromAddress: fromAddress,
-		toAddress:   toAddress,
-		sendAmount:  sendAmount,
+	cfg := PrepareCfg{
+		FromAddress: fromAddress,
+		ToAddress:   toAddress,
+		SendAmount:  sendAmount,
 	}
 
-	tx := prepareTransaction(mockEstimator, cfg)
+	tx := prepareTransaction(mockEstimator, defaultPrepareTxMessage(cfg))
 
 	// Make sure the transaction was created
 	require.NotNil(t, tx)

transfer.go

@@ -18,12 +18,12 @@ func (f *Faucet) transferFunds(address crypto.Address) error {
 	}
 
 	// Prepare the transaction
-	pCfg := prepareCfg{
-		fromAddress: fundAccount.GetAddress(),
-		toAddress:   address,
-		sendAmount:  f.sendAmount,
+	pCfg := PrepareCfg{
+		FromAddress: fundAccount.GetAddress(),
+		ToAddress:   address,
+		SendAmount:  f.sendAmount,
 	}
-	tx := prepareTransaction(f.estimator, pCfg)
+	tx := prepareTransaction(f.estimator, f.prepareTxMsgFn(pCfg))
 
 	// Sign the transaction
 	sCfg := signCfg{