feat(server/v2): add min gas price and check with tx fee

server/v2/commands.go

@@ -38,13 +38,14 @@ func AddCommands[T transaction.Tx](
 	rootCmd *cobra.Command,
 	newApp AppCreator[T],
 	logger log.Logger,
+	serverCfg ServerConfig,
 	components ...ServerComponent[T],
 ) error {
 	if len(components) == 0 {
 		return errors.New("no components provided")
 	}
 
-	server := NewServer(logger, components...)
+	server := NewServer(logger, serverCfg, components...)
 	originalPersistentPreRunE := rootCmd.PersistentPreRunE
 	rootCmd.PersistentPreRunE = func(cmd *cobra.Command, args []string) error {
 		// set the default command outputs

server/v2/config.go

@@ -7,6 +7,18 @@ import (
 	"github.com/spf13/viper"
 )
 
+// ServerConfig defines configuration for the server component.
+type ServerConfig struct {
+	MinGasPrices string `mapstructure:"minimum-gas-prices" toml:"minimum-gas-prices" comment:"minimum-gas-prices defines the price which a validator is willing to accept for processing a transaction. A transaction's fees must meet the minimum of any denomination specified in this config (e.g. 0.25token1;0.0001token2)."`
+}
+
+// DefaultServerConfig returns the default config of server component
+func DefaultServerConfig() ServerConfig {
+	return ServerConfig{
+		MinGasPrices: "0stake",
+	}
+}
+
 // ReadConfig returns a viper instance of the config file
 func ReadConfig(configPath string) (*viper.Viper, error) {
 	v := viper.New()

server/v2/flags.go

@@ -1,6 +1,16 @@
 // Package serverv2 defines constants for server configuration flags and output formats.
 package serverv2
 
+import "fmt"
+
+// start flags are prefixed with the server name
+// this allows viper to properly bind the flags
+func prefix(f string) string {
+	return fmt.Sprintf("%s.%s", serverName, f)
+}
+
+var FlagMinGasPrices = prefix("minimum-gas-prices")
+
 const (
 	// FlagHome specifies the home directory flag.
 	FlagHome = "home"

server/v2/server.go

@@ -56,25 +56,32 @@ type CLIConfig struct {
 	Txs []*cobra.Command
 }
 
+const (
+	serverName = "server"
+)
+
 var _ ServerComponent[transaction.Tx] = (*Server[transaction.Tx])(nil)
 
 type Server[T transaction.Tx] struct {
 	logger     log.Logger
 	components []ServerComponent[T]
+	config     ServerConfig
 }
 
 func NewServer[T transaction.Tx](
 	logger log.Logger,
+	config ServerConfig,
 	components ...ServerComponent[T],
 ) *Server[T] {
 	return &Server[T]{
 		logger:     logger,
+		config:     config,
 		components: components,
 	}
 }
 
 func (s *Server[T]) Name() string {
-	return "server"
+	return serverName
 }
 
 // Start starts all components concurrently.
@@ -151,9 +158,19 @@ func (s *Server[T]) CLICommands() CLIConfig {
 	return commands
 }
 
+// Config returns config of the server component
+func (s *Server[T]) Config() ServerConfig {
+	return s.config
+}
+
 // Configs returns all configs of all server components.
 func (s *Server[T]) Configs() map[string]any {
 	cfgs := make(map[string]any)
+
+	// add server component config
+	cfgs[s.Name()] = s.config
+
+	// add other components' config
 	for _, mod := range s.components {
 		if configmod, ok := mod.(HasConfig); ok {
 			cfg := configmod.Config()
@@ -164,9 +181,22 @@ func (s *Server[T]) Configs() map[string]any {
 	return cfgs
 }
 
+func (s *Server[T]) StartCmdFlags() *pflag.FlagSet {
+	flags := pflag.NewFlagSet(s.Name(), pflag.ExitOnError)
+	flags.String(FlagMinGasPrices, "", "Minimum gas prices to accept for transactions; Any fee in a tx must meet this minimum (e.g. 0.01photino;0.0001stake)")
+	return flags
+}
+
 // Init initializes all server components with the provided application, configuration, and logger.
 // It returns an error if any component fails to initialize.
 func (s *Server[T]) Init(appI AppI[T], v *viper.Viper, logger log.Logger) error {
+	cfg := s.config
+	if v != nil {
+		if err := UnmarshalSubConfig(v, s.Name(), &cfg); err != nil {
+			return fmt.Errorf("failed to unmarshal config: %w", err)
+		}
+	}
+
 	var components []ServerComponent[T]
 	for _, mod := range s.components {
 		mod := mod
@@ -177,6 +207,7 @@ func (s *Server[T]) Init(appI AppI[T], v *viper.Viper, logger log.Logger) error
 		components = append(components, mod)
 	}
 
+	s.config = cfg
 	s.components = components
 	return nil
 }
@@ -217,6 +248,11 @@ func (s *Server[T]) WriteConfig(configPath string) error {
 // StartFlags returns all flags of all server components.
 func (s *Server[T]) StartFlags() []*pflag.FlagSet {
 	flags := []*pflag.FlagSet{}
+
+	// add server component flags
+	flags = append(flags, s.StartCmdFlags())
+
+	// add other components' start cmd flags
 	for _, mod := range s.components {
 		if startmod, ok := mod.(HasStartFlags); ok {
 			flags = append(flags, startmod.StartCmdFlags())

server/v2/server_test.go

@@ -65,6 +65,7 @@ func TestServer(t *testing.T) {
 
 	server := serverv2.NewServer(
 		logger,
+		serverv2.DefaultServerConfig(),
 		grpcServer,
 		mockServer,
 	)

server/v2/testdata/app.toml

@@ -10,6 +10,10 @@ max-recv-msg-size = 10485760
 # The default value is math.MaxInt32.
 max-send-msg-size = 2147483647
 
+[server]
+# minimum-gas-prices defines the price which a validator is willing to accept for processing a transaction. A transaction's fees must meet the minimum of any denomination specified in this config (e.g. 0.25token1;0.0001token2).
+minimum-gas-prices = '0stake'
+
 [store]
 # The type of database for application and snapshots databases.
 app-db-backend = 'goleveldb'

simapp/v2/simdv2/cmd/commands.go

@@ -75,6 +75,7 @@ func initRootCmd[T transaction.Tx](
 		rootCmd,
 		newApp,
 		logger,
+		initServerConfig(),
 		cometbft.New(&genericTxDecoder[T]{txConfig}, cometbft.DefaultServerOptions[T]()),
 		grpc.New[T](),
 		store.New[T](newApp),

simapp/v2/simdv2/cmd/config.go

@@ -3,6 +3,8 @@ package cmd
 import (
 	"strings"
 
+	serverv2 "cosmossdk.io/server/v2"
+
 	clientconfig "github.com/cosmos/cosmos-sdk/client/config"
 	"github.com/cosmos/cosmos-sdk/crypto/keyring"
 )
@@ -49,3 +51,20 @@ gas-adjustment = {{ .GasConfig.GasAdjustment }}
 
 	return customClientConfigTemplate, customClientConfig
 }
+
+// Allow the chain developer to overwrite the server default app toml config.
+func initServerConfig() serverv2.ServerConfig {
+	serverCfg := serverv2.DefaultServerConfig()
+	// The server's default minimum gas price is set to "0stake" inside
+	// app.toml. However, the chain developer can set a default app.toml value for their
+	// validators here. Please update value based on chain denom.
+	//
+	// In summary:
+	// - if you set serverCfg.MinGasPrices value, validators CAN tweak their
+	//   own app.toml to override, or use this default value.
+	//
+	// In simapp, we set the min gas prices to 0.
+	serverCfg.MinGasPrices = "0stake"
+
+	return serverCfg
+}

simapp/v2/simdv2/cmd/testnet.go

@@ -41,7 +41,6 @@ import (
 )
 
 var (
-	flagMinGasPrices      = "minimum-gas-prices"
 	flagNodeDirPrefix     = "node-dir-prefix"
 	flagNumValidators     = "validator-count"
 	flagOutputDir         = "output-dir"
@@ -72,7 +71,7 @@ func addTestnetFlagsToCmd(cmd *cobra.Command) {
 	cmd.Flags().IntP(flagNumValidators, "n", 4, "Number of validators to initialize the testnet with")
 	cmd.Flags().StringP(flagOutputDir, "o", "./.testnets", "Directory to store initialization data for the testnet")
 	cmd.Flags().String(flags.FlagChainID, "", "genesis file chain-id, if left blank will be randomly created")
-	cmd.Flags().String(flagMinGasPrices, fmt.Sprintf("0.000006%s", sdk.DefaultBondDenom), "Minimum gas prices to accept for transactions; All fees in a tx must meet this minimum (e.g. 0.01photino,0.001stake)")
+	cmd.Flags().String(serverv2.FlagMinGasPrices, fmt.Sprintf("0.000006%s", sdk.DefaultBondDenom), "Minimum gas prices to accept for transactions; All fees in a tx must meet this minimum (e.g. 0.01photino,0.001stake)")
 	cmd.Flags().String(flags.FlagKeyType, string(hd.Secp256k1Type), "Key signing algorithm to generate keys for")
 
 	// support old flags name for backwards compatibility
@@ -129,7 +128,7 @@ Example:
 			args.outputDir, _ = cmd.Flags().GetString(flagOutputDir)
 			args.keyringBackend, _ = cmd.Flags().GetString(flags.FlagKeyringBackend)
 			args.chainID, _ = cmd.Flags().GetString(flags.FlagChainID)
-			args.minGasPrices, _ = cmd.Flags().GetString(flagMinGasPrices)
+			args.minGasPrices, _ = cmd.Flags().GetString(serverv2.FlagMinGasPrices)
 			args.nodeDirPrefix, _ = cmd.Flags().GetString(flagNodeDirPrefix)
 			args.nodeDaemonHome, _ = cmd.Flags().GetString(flagNodeDaemonHome)
 			args.startingIPAddress, _ = cmd.Flags().GetString(flagStartingIPAddress)
@@ -337,6 +336,9 @@ func initTestnetFiles[T transaction.Tx](
 			return err
 		}
 
+		serverCfg := serverv2.DefaultServerConfig()
+		serverCfg.MinGasPrices = args.minGasPrices
+
 		// Write server config
 		cometServer := cometbft.New[T](
 			&genericTxDecoder[T]{clientCtx.TxConfig},
@@ -345,7 +347,7 @@ func initTestnetFiles[T transaction.Tx](
 		)
 		storeServer := store.New[T](newApp)
 		grpcServer := grpc.New[T](grpc.OverwriteDefaultConfig(grpcConfig))
-		server := serverv2.NewServer(log.NewNopLogger(), cometServer, grpcServer, storeServer)
+		server := serverv2.NewServer(log.NewNopLogger(), serverCfg, cometServer, grpcServer, storeServer)
 		err = server.WriteConfig(filepath.Join(nodeDir, "config"))
 		if err != nil {
 			return err

tests/systemtests/staking_test.go

@@ -10,7 +10,6 @@ import (
 )
 
 func TestStakeUnstake(t *testing.T) {
-	t.Skip("The fee deduction is not yet implemented in v2")
 	// Scenario:
 	// delegate tokens to validator
 	// undelegate some tokens

tools/confix/data/v2-app.toml

@@ -28,6 +28,10 @@ max-recv-msg-size = 10485760
 # The default value is math.MaxInt32.
 max-send-msg-size = 2147483647
 
+[server]
+# minimum-gas-prices defines the price which a validator is willing to accept for processing a transaction. A transaction's fees must meet the minimum of any denomination specified in this config (e.g. 0.25token1;0.0001token2).
+minimum-gas-prices = '0stake'
+
 [store]
 # The type of database for application and snapshots databases.
 app-db-backend = 'goleveldb'

tools/confix/migrations.go

@@ -39,11 +39,12 @@ type v2KeyChangesMap map[string][]string
 
 // list all the keys which are need to be modified in v2
 var v2KeyChanges = v2KeyChangesMap{
-	"min-retain-blocks": []string{"comet.min-retain-blocks"},
-	"index-events":      []string{"comet.index-events"},
-	"halt-height":       []string{"comet.halt-height"},
-	"halt-time":         []string{"comet.halt-time"},
-	"app-db-backend":    []string{"store.app-db-backend"},
+	"minimum-gas-prices": []string{"server.minimum-gas-prices"},
+	"min-retain-blocks":  []string{"comet.min-retain-blocks"},
+	"index-events":       []string{"comet.index-events"},
+	"halt-height":        []string{"comet.halt-height"},
+	"halt-time":          []string{"comet.halt-time"},
+	"app-db-backend":     []string{"store.app-db-backend"},
 	"pruning-keep-recent": []string{
 		"store.options.ss-pruning-option.keep-recent",
 		"store.options.sc-pruning-option.keep-recent",