feat(plugin): add configuration to run go package

internal/cmd/generate.go

@@ -349,6 +349,7 @@ func codegen(ctx context.Context, combo config.CombinedSettings, sql OutputPair,
 		switch {
 		case plug.Process != nil:
 			handler = &process.Runner{
+				GoPkg:  plug.Process.GoPkg,
 				Cmd:    plug.Process.Cmd,
 				Env:    plug.Env,
 				Format: plug.Process.Format,

internal/config/config.go

@@ -89,6 +89,7 @@ type Plugin struct {
 	Name    string   `json:"name" yaml:"name"`
 	Env     []string `json:"env" yaml:"env"`
 	Process *struct {
+		GoPkg  string `json:"go_package" yaml:"go_package"`
 		Cmd    string `json:"cmd" yaml:"cmd"`
 		Format string `json:"format" yaml:"format"`
 	} `json:"process" yaml:"process"`
@@ -159,7 +160,8 @@ var ErrPluginExists = errors.New("a plugin with that name already exists")
 var ErrPluginNotFound = errors.New("no plugin found")
 var ErrPluginNoType = errors.New("plugin: field `process` or `wasm` required")
 var ErrPluginBothTypes = errors.New("plugin: `process` and `wasm` cannot both be defined")
-var ErrPluginProcessNoCmd = errors.New("plugin: missing process command")
+var ErrPluginProcessTooManyCmd = errors.New("plugin: only one of `cmd` or `go_package` is allowed for process plugin")
+var ErrPluginProcessNoCmd = errors.New("plugin: missing `cmd` or `go_package` for process plugin")
 
 var ErrInvalidDatabase = errors.New("database must be managed or have a non-empty URI")
 var ErrManagedDatabaseNoProject = errors.New(`managed databases require a cloud project

internal/config/v_two.go

@@ -48,8 +48,11 @@ func v2ParseConfig(rd io.Reader) (Config, error) {
 		if conf.Plugins[i].Process != nil && conf.Plugins[i].WASM != nil {
 			return conf, ErrPluginBothTypes
 		}
-		if conf.Plugins[i].Process != nil {
-			if conf.Plugins[i].Process.Cmd == "" {
+		if r := conf.Plugins[i].Process; r != nil {
+			switch {
+			case r.Cmd != "" && r.GoPkg != "":
+				return conf, ErrPluginProcessTooManyCmd
+			case r.Cmd == "" && r.GoPkg == "":
 				return conf, ErrPluginProcessNoCmd
 			}
 		}

internal/ext/process/gen.go

@@ -19,6 +19,7 @@ import (
 )
 
 type Runner struct {
+	GoPkg  string
 	Cmd    string
 	Format string
 	Env    []string
@@ -53,13 +54,39 @@ func (r *Runner) Invoke(ctx context.Context, method string, args any, reply any,
 		return fmt.Errorf("unknown plugin format: %s", r.Format)
 	}
 
-	// Check if the output plugin exists
-	path, err := exec.LookPath(r.Cmd)
-	if err != nil {
-		return fmt.Errorf("process: %s not found", r.Cmd)
+	var cmd *exec.Cmd
+	switch {
+	case r.Cmd != "":
+		// Check if the output plugin exists
+		path, err := exec.LookPath(r.Cmd)
+		if err != nil {
+			return fmt.Errorf("process: %s not found", r.Cmd)
+		}
+		cmd = exec.CommandContext(ctx, path, method)
+	case r.GoPkg != "":
+		// Check if the go binary exists
+		path, err := exec.LookPath("go")
+		if err != nil {
+			return fmt.Errorf("go binary required to run go package %s", r.GoPkg)
+		}
+		cmd = exec.CommandContext(ctx, path, method)
+		cmd.Args = []string{"go", "run", r.GoPkg}
+		r.Env = append(r.Env, []string{
+			"GO111MODULE",
+			"GOROOT",
+			"GOPATH",
+			"GOPROXY",
+			"GOPRIVATE",
+			"GONOPROXY",
+			"GONOSUMDB",
+			"GOMODCACHE",
+			"GOFLAGS",
+			"GOCACHE",
+			"GOENV",
+			"HOME",
+		}...)
 	}
 
-	cmd := exec.CommandContext(ctx, path, method)
 	cmd.Stdin = bytes.NewReader(stdin)
 	cmd.Env = []string{
 		fmt.Sprintf("SQLC_VERSION=%s", info.Version),