cli: add embedded node config

If `config-path` is not passed, default configs are used according to
the set network. In VM CLI the default privnet config with InMemory db
is used.

Close #3450

Signed-off-by: Ekaterina Pavlova <ekt@morphbits.io>

cli/options/options.go

@@ -201,7 +201,7 @@ func GetConfigFromContext(ctx *cli.Context) (config.Config, error) {
 	if len(configFile) != 0 {
 		return config.LoadFile(configFile, relativePath)
 	}
-	var configPath = "./config"
+	var configPath = config.DefaultConfigPath
 	if argCp := ctx.String("config-path"); argCp != "" {
 		configPath = argCp
 	}

config/config_embed.go

@@ -0,0 +1,33 @@
+// Package config contains embedded YAML configuration files for different network modes
+// of the Neo N3 blockchain and NeoFS. This includes configurations for the mainnet,
+// testnet, and private network environments.
+package config
+
+import (
+	_ "embed"
+)
+
+// Mainnet is the Neo N3 mainnet configuration.
+//
+//go:embed protocol.mainnet.yml
+var Mainnet []byte
+
+// Testnet is the Neo N3 testnet configuration.
+//
+//go:embed protocol.testnet.yml
+var Testnet []byte
+
+// Privnet is the private network configuration.
+//
+//go:embed protocol.privnet.yml
+var Privnet []byte
+
+// MainnetNeoFS is the mainnet NeoFS configuration.
+//
+//go:embed protocol.mainnet.neofs.yml
+var MainnetNeoFS []byte
+
+// TestnetNeoFS is the testnet NeoFS configuration.
+//
+//go:embed protocol.testnet.neofs.yml
+var TestnetNeoFS []byte

pkg/config/config.go

@@ -6,8 +6,8 @@ import (
 	"net/http"
 	"os"
 	"path/filepath"
-	"time"
 
+	"github.com/nspcc-dev/neo-go/config"
 	"github.com/nspcc-dev/neo-go/pkg/config/netmode"
 	"gopkg.in/yaml.v3"
 )
@@ -38,6 +38,8 @@ const (
 	// DefaultMaxRequestHeaderBytes is the maximum permitted size of the headers
 	// in an HTTP request.
 	DefaultMaxRequestHeaderBytes = http.DefaultMaxHeaderBytes
+	// DefaultConfigPath is the default path to the config directory.
+	DefaultConfigPath = "./config"
 )
 
 // Version is the version of the node, set at the build time.
@@ -76,22 +78,25 @@ func Load(path string, netMode netmode.Magic, relativePath ...string) (Config, e
 // fixups if necessary. If relativePath is not empty, relative paths in the config will
 // be updated based on the provided relative path.
 func LoadFile(configPath string, relativePath ...string) (Config, error) {
-	if _, err := os.Stat(configPath); os.IsNotExist(err) {
-		return Config{}, fmt.Errorf("config '%s' doesn't exist", configPath)
-	}
+	var (
+		configData []byte
+		err        error
+		config     Config
+	)
 
-	configData, err := os.ReadFile(configPath)
-	if err != nil {
-		return Config{}, fmt.Errorf("unable to read config: %w", err)
-	}
-
-	config := Config{
-		ApplicationConfiguration: ApplicationConfiguration{
-			P2P: P2P{
-				PingInterval: 30 * time.Second,
-				PingTimeout:  90 * time.Second,
-			},
-		},
+	if _, err = os.Stat(configPath); os.IsNotExist(err) {
+		if filepath.Dir(configPath) != DefaultConfigPath {
+			return Config{}, fmt.Errorf("config '%s' doesn't exist", configPath)
+		}
+		configData, err = getEmbeddedConfig(configPath)
+		if err != nil {
+			return Config{}, err
+		}
+	} else {
+		configData, err = os.ReadFile(configPath)
+		if err != nil {
+			return Config{}, fmt.Errorf("unable to read config: %w", err)
+		}
 	}
 	decoder := yaml.NewDecoder(bytes.NewReader(configData))
 	decoder.KnownFields(true)
@@ -111,6 +116,24 @@ func LoadFile(configPath string, relativePath ...string) (Config, error) {
 	return config, nil
 }
 
+// getEmbeddedConfig returns the embedded config based on the provided config path.
+func getEmbeddedConfig(configPath string) ([]byte, error) {
+	switch configPath {
+	case fmt.Sprintf("%s/protocol.%s.yml", DefaultConfigPath, netmode.MainNet.String()):
+		return config.Mainnet, nil
+	case fmt.Sprintf("%s/protocol.%s.yml", DefaultConfigPath, netmode.TestNet.String()):
+		return config.Testnet, nil
+	case fmt.Sprintf("%s/protocol.%s.yml", DefaultConfigPath, netmode.PrivNet.String()):
+		return config.Privnet, nil
+	case fmt.Sprintf("%s/protocol.mainnet.neofs.yml", DefaultConfigPath):
+		return config.MainnetNeoFS, nil
+	case fmt.Sprintf("%s/protocol.testnet.neofs.yml", DefaultConfigPath):
+		return config.TestnetNeoFS, nil
+	default:
+		return nil, fmt.Errorf("no embedded config matches path: %s", configPath)
+	}
+}
+
 // updateRelativePaths updates relative paths in the config structure based on the provided relative path.
 func updateRelativePaths(relativePath string, config *Config) {
 	updatePath := func(path *string) {

pkg/config/config_test.go

@@ -32,3 +32,25 @@ func TestUnknownConfigFields(t *testing.T) {
 		require.Contains(t, err.Error(), "field UnknownConfigurationField not found in type config.Config")
 	})
 }
+
+func TestLoadFileWithMissingDefaultConfigPath(t *testing.T) {
+	originalPath := DefaultConfigPath
+	temporaryPath := filepath.Join(filepath.Dir(originalPath), "missing-config")
+
+	if _, err := os.Stat(originalPath); os.IsNotExist(err) {
+		err = os.MkdirAll(originalPath, os.ModePerm)
+		require.NoError(t, err)
+	}
+
+	t.Cleanup(func() {
+		err := os.Rename(temporaryPath, originalPath)
+		require.NoError(t, err)
+	})
+
+	err := os.Rename(originalPath, temporaryPath)
+	require.NoError(t, err)
+
+	_, err = LoadFile(filepath.Join(DefaultConfigPath, "protocol.privnet.yml"))
+	require.Error(t, err)
+	require.Contains(t, err.Error(), "doesn't exist")
+}