goctl model reactor (#15)

* reactor sql generation

* reactor sql generation

* add console & example

* optimize unit test & add document

* modify default config

* remove test file

* Revert "remove test file"

This reverts commit 81041f9e

* fix stringx.go & optimize example

* remove unused code

tools/goctl/util/templatex/templatex.go

@@ -0,0 +1,67 @@
+package templatex
+
+import (
+	"bytes"
+	goformat "go/format"
+	"io/ioutil"
+	"os"
+	"text/template"
+)
+
+type (
+	defaultTemplate struct {
+		name     string
+		text     string
+		goFmt    bool
+		savePath string
+	}
+)
+
+func With(name string) *defaultTemplate {
+	return &defaultTemplate{
+		name: name,
+	}
+}
+func (t *defaultTemplate) Parse(text string) *defaultTemplate {
+	t.text = text
+	return t
+}
+
+func (t *defaultTemplate) GoFmt(format bool) *defaultTemplate {
+	t.goFmt = format
+	return t
+}
+
+func (t *defaultTemplate) SaveTo(data interface{}, path string) error {
+	output, err := t.execute(data)
+	if err != nil {
+		return err
+	}
+	return ioutil.WriteFile(path, output.Bytes(), os.ModePerm)
+}
+
+func (t *defaultTemplate) Execute(data interface{}) (*bytes.Buffer, error) {
+	return t.execute(data)
+}
+
+func (t *defaultTemplate) execute(data interface{}) (*bytes.Buffer, error) {
+	tem, err := template.New(t.name).Parse(t.text)
+	if err != nil {
+		return nil, err
+	}
+	buf := new(bytes.Buffer)
+	err = tem.Execute(buf, data)
+	if err != nil {
+		return nil, err
+	}
+	if !t.goFmt {
+		return buf, nil
+	}
+	formatOutput, err := goformat.Source(buf.Bytes())
+	if err != nil {
+		return nil, err
+	}
+	buf.Reset()
+	buf.Write(formatOutput)
+	return buf, nil
+}