📦 new: use configbuilder to parse config files into Config struct (#25)

* new: configbuilder.ConfigJSON

* fix: unused wasmClone

* new: configbuilder.ConfigProtoBuf

Plus, make configbuilder no longer an internal package.

* feat: UnmarshalJSON and UnmarshalProto for Config

* deprecated: use of Argv and Env inside WATM

Deprecate the use of `argv` and `env` inside a WATM. A WATM is encouraged to be configured with `Config.TransportModuleConfig`. To prevent the unnecessary warning this may introduce to some undocumented legitimate use, we will not add `Deprecated` flag on the related fields and functions.

Signed-off-by: Gaukas Wang <[email protected]>

---------

Signed-off-by: Gaukas Wang <[email protected]>

Author: gaukas

config.go

@@ -1,10 +1,15 @@
 package water
 
 import (
+	"encoding/json"
+	"errors"
 	"net"
+	"os"
 
+	"github.com/gaukas/water/configbuilder"
 	"github.com/gaukas/water/internal/log"
 	"github.com/gaukas/water/internal/wasm"
+	"google.golang.org/protobuf/proto"
 )
 
 // Config defines the configuration for the WATER Dialer/Config interface.
@@ -56,7 +61,7 @@ func (c *Config) Clone() *Config {
 	copy(wasmClone, c.TransportModuleBin)
 
 	return &Config{
-		TransportModuleBin:    c.TransportModuleBin,
+		TransportModuleBin:    wasmClone,
 		NetworkDialerFunc:     c.NetworkDialerFunc,
 		NetworkListener:       c.NetworkListener,
 		TransportModuleConfig: c.TransportModuleConfig,
@@ -126,3 +131,133 @@ func (c *Config) Logger() *log.Logger {
 
 	return log.GetDefaultLogger()
 }
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (c *Config) UnmarshalJSON(data []byte) error {
+	var confJson configbuilder.ConfigJSON
+
+	err := json.Unmarshal(data, &confJson)
+	if err != nil {
+		return err
+	}
+
+	tmBin, err := os.ReadFile(confJson.TransportModule.BinPath)
+	if err != nil {
+		return err
+	}
+	c.TransportModuleBin = tmBin
+
+	if len(confJson.TransportModule.ConfigPath) > 0 {
+		c.TransportModuleConfig, err = TransportModuleConfigFromFile(confJson.TransportModule.ConfigPath)
+		if err != nil {
+			return err
+		}
+	}
+
+	if len(confJson.Network.Listener.Network) > 0 && len(confJson.Network.Listener.Address) > 0 {
+		c.NetworkListener, err = net.Listen(confJson.Network.Listener.Network, confJson.Network.Listener.Address)
+		if err != nil {
+			return err
+		}
+	}
+
+	c.ModuleConfigFactory = wasm.NewModuleConfigFactory()
+	if len(confJson.Module.Argv) > 0 {
+		c.ModuleConfigFactory.SetArgv(confJson.Module.Argv)
+	}
+
+	var envKeys []string
+	var envValues []string
+	for k, v := range confJson.Module.Env {
+		envKeys = append(envKeys, k)
+		envValues = append(envValues, v)
+	}
+	if len(envKeys) > 0 {
+		c.ModuleConfigFactory.SetEnv(envKeys, envValues)
+	}
+
+	if confJson.Module.InheritStdin {
+		c.ModuleConfigFactory.InheritStdin()
+	}
+
+	if confJson.Module.InheritStdout {
+		c.ModuleConfigFactory.InheritStdout()
+	}
+
+	if confJson.Module.InheritStderr {
+		c.ModuleConfigFactory.InheritStderr()
+	}
+
+	for k, v := range confJson.Module.PreopenedDirs {
+		c.ModuleConfigFactory.SetPreopenDir(k, v)
+	}
+
+	return nil
+}
+
+// UnmarshalProto provides a way to unmarshal a protobuf message into a Config.
+//
+// The message definition is defined in configbuilder/pb/config.proto.
+func (c *Config) UnmarshalProto(b []byte) error {
+	var confProto configbuilder.ConfigProtoBuf
+
+	unmarshalOptions := proto.UnmarshalOptions{
+		AllowPartial: true,
+	}
+	err := unmarshalOptions.Unmarshal(b, &confProto)
+	if err != nil {
+		return err
+	}
+
+	// Parse TransportModuleBin
+	c.TransportModuleBin = confProto.GetTransportModule().GetBin()
+	if len(c.TransportModuleBin) == 0 {
+		return errors.New("water: transport module binary is not provided in config")
+	}
+
+	// Parse TransportModuleConfig
+	c.TransportModuleConfig = TransportModuleConfigFromBytes(confProto.GetTransportModule().GetConfig())
+
+	// Parse NetworkListener
+	listenerNetwork, listenerAddress := confProto.GetNetwork().GetListener().GetNetwork(), confProto.GetNetwork().GetListener().GetAddress()
+	if len(listenerNetwork) > 0 && len(listenerAddress) > 0 {
+		c.NetworkListener, err = net.Listen(listenerNetwork, listenerAddress)
+		if err != nil {
+			return err
+		}
+	}
+
+	// Parse ModuleConfigFactory
+	c.ModuleConfigFactory = wasm.NewModuleConfigFactory()
+	if len(confProto.GetModule().GetArgv()) > 0 {
+		c.ModuleConfigFactory.SetArgv(confProto.Module.Argv)
+	}
+
+	var envKeys []string
+	var envValues []string
+	for k, v := range confProto.GetModule().GetEnv() {
+		envKeys = append(envKeys, k)
+		envValues = append(envValues, v)
+	}
+	if len(envKeys) > 0 {
+		c.ModuleConfigFactory.SetEnv(envKeys, envValues)
+	}
+
+	if confProto.GetModule().GetInheritStdin() {
+		c.ModuleConfigFactory.InheritStdin()
+	}
+
+	if confProto.GetModule().GetInheritStdout() {
+		c.ModuleConfigFactory.InheritStdout()
+	}
+
+	if confProto.GetModule().GetInheritStderr() {
+		c.ModuleConfigFactory.InheritStderr()
+	}
+
+	for k, v := range confProto.GetModule().GetPreopenedDirs() {
+		c.ModuleConfigFactory.SetPreopenDir(k, v)
+	}
+
+	return nil
+}

configbuilder/config.json.go

@@ -0,0 +1,29 @@
+package configbuilder
+
+// ConfigJSON defines the JSON format of the Config.
+//
+// This struct may fail to fully represent the Config struct, as it is
+// non-trivial to represent a func or other non-serialized structures.
+type ConfigJSON struct {
+	TransportModule struct {
+		BinPath    string `json:"bin"`              // Path to the transport module binary
+		ConfigPath string `json:"config,omitempty"` // Path to the transport module config file
+	} `json:"transport_module"`
+
+	Network struct {
+		// DialerFunc string `json:"dialer_func,omitempty"` // we have no good way to represent a func in JSON format yet
+		Listener struct {
+			Network string `json:"network"` // e.g. "tcp"
+			Address string `json:"address"` // e.g. "0.0.0.0:0"
+		} `json:"listener,omitempty"`
+	} `json:"network,omitempty"`
+
+	Module struct {
+		Argv          []string          `json:"argv,omitempty"` // Warning: this isn't a recommended way to pass configuration to the WebAssembly module. Instead, use TransportModuleConfig for a serializable configuration file.
+		Env           map[string]string `json:"env,omitempty"`  // Warning: this isn't a recommended way to pass configuration to the WebAssembly module. Instead, use TransportModuleConfig for a serializable configuration file.
+		InheritStdin  bool              `json:"inherit_stdin,omitempty"`
+		InheritStdout bool              `json:"inherit_stdout,omitempty"`
+		InheritStderr bool              `json:"inherit_stderr,omitempty"`
+		PreopenedDirs map[string]string `json:"preopened_dirs,omitempty"` // hostPath: guestPath
+	} `json:"module,omitempty"`
+}

configbuilder/config.pb.go

@@ -0,0 +1,9 @@
+package configbuilder
+
+import "github.com/gaukas/water/configbuilder/pb"
+
+// ConfigProtoBuf defines the Protobuf format of the Config.
+//
+// This struct may fail to fully represent the Config struct, as it is
+// non-trivial to represent a func or other non-serialized structures.
+type ConfigProtoBuf = pb.Config

configbuilder/pb/Makefile

@@ -0,0 +1,4 @@
+protobuf: config.proto
+	protoc --go_out=. --go_opt=paths=source_relative $<
+
+.PHONY: protobuf