feat(goctl): supports model code 'DO NOT EDIT' (#1728)

Resolves: #1710

tools/goctl/model/sql/template/model.go

@@ -1,7 +1,15 @@
 package template
 
-// Model defines a template for model
-var Model = `package {{.pkg}}
+import (
+	"fmt"
+
+	"github.com/zeromicro/go-zero/tools/goctl/util"
+)
+
+// ModelGen defines a template for model
+var ModelGen = fmt.Sprintf(`%s
+
+package {{.pkg}}
 {{.imports}}
 {{.vars}}
 {{.types}}
@@ -11,4 +19,11 @@ var Model = `package {{.pkg}}
 {{.update}}
 {{.delete}}
 {{.extraMethod}}
-`
+`, util.DoNotEditHead)
+
+// ModelCustom defines a template for extension
+var ModelCustom = fmt.Sprintf(`package {{.pkg}}
+type {{.upperStartCamelObject}}Model interface {
+	{{.lowerStartCamelObject}}Model
+}
+`)

tools/goctl/model/sql/template/types.go

@@ -3,7 +3,7 @@ package template
 // Types defines a template for types in model
 var Types = `
 type (
-	{{.upperStartCamelObject}}Model interface{
+	{{.lowerStartCamelObject}}Model interface{
 		{{.method}}
 	}
 

tools/goctl/model/sql/template/vars.go

@@ -5,6 +5,8 @@ import "fmt"
 // Vars defines a template for var block in model
 var Vars = fmt.Sprintf(`
 var (
+	_ {{.upperStartCamelObject}}Model = (*default{{.upperStartCamelObject}}Model)(nil)
+
 	{{.lowerStartCamelObject}}FieldNames          = builder.RawFieldNames(&{{.upperStartCamelObject}}{}{{if .postgreSql}},true{{end}})
 	{{.lowerStartCamelObject}}Rows                = strings.Join({{.lowerStartCamelObject}}FieldNames, ",")
 	{{.lowerStartCamelObject}}RowsExpectAutoSet   = {{if .postgreSql}}strings.Join(stringx.Remove({{.lowerStartCamelObject}}FieldNames, {{if .autoIncrement}}"{{.originalPrimaryKey}}",{{end}} "%screate_time%s", "%supdate_time%s"), ","){{else}}strings.Join(stringx.Remove({{.lowerStartCamelObject}}FieldNames, {{if .autoIncrement}}"{{.originalPrimaryKey}}",{{end}} "%screate_time%s", "%supdate_time%s"), ","){{end}}