feat: use go:embed to embed templates (#1756)

tools/goctl/api/tsgen/components.tpl

@@ -0,0 +1,3 @@
+/ Code generated by goctl. DO NOT EDIT.
+
+{{.componentTypes}}

tools/goctl/api/tsgen/gencomponents.go

@@ -1,6 +1,7 @@
 package tsgen
 
 import (
+	_ "embed"
 	"path"
 	"strings"
 	"text/template"
@@ -10,12 +11,8 @@ import (
 	"github.com/zeromicro/go-zero/tools/goctl/util/pathx"
 )
 
-const (
-	componentsTemplate = `// Code generated by goctl. DO NOT EDIT.
-
-{{.componentTypes}}
-`
-)
+//go:embed components.tpl
+var componentsTemplate string
 
 func genComponents(dir string, api *spec.ApiSpec) error {
 	types := api.Types

tools/goctl/api/tsgen/genpacket.go

@@ -1,6 +1,7 @@
 package tsgen
 
 import (
+	_ "embed"
 	"fmt"
 	"path"
 	"strings"
@@ -12,12 +13,8 @@ import (
 	"github.com/zeromicro/go-zero/tools/goctl/util/pathx"
 )
 
-const (
-	handlerTemplate = `{{.imports}}
-
-{{.apis}}
-`
-)
+//go:embed handler.tpl
+var handlerTemplate string
 
 func genHandler(dir, webAPI, caller string, api *spec.ApiSpec, unwrapAPI bool) error {
 	filename := strings.Replace(api.Service.Name, "-api", "", 1) + ".ts"

tools/goctl/api/tsgen/handler.tpl

@@ -0,0 +1,3 @@
+{{.imports}}
+
+{{.apis}}