https://github.com/fatih/structtag

Parse and modify Go struct field tags
https://github.com/fatih/structtag

go structs tags

Last synced: 18 days ago
JSON representation

Parse and modify Go struct field tags

• Host: GitHub
• URL: https://github.com/fatih/structtag
• Owner: fatih
• License: other
• Created: 2017-01-23T14:56:21.000Z (almost 8 years ago)
• Default Branch: master
• Last Pushed: 2023-09-07T20:17:17.000Z (about 1 year ago)
• Last Synced: 2024-10-09T17:26:23.059Z (30 days ago)
• Topics: go, structs, tags
• Language: Go
• Size: 11.7 KB
• Stars: 630
• Watchers: 15
• Forks: 40
• Open Issues: 5
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Awesome Lists containing this project

README

        
# structtag [![](https://github.com/fatih/structtag/workflows/build/badge.svg)](https://github.com/fatih/structtag/actions) [![PkgGoDev](https://pkg.go.dev/badge/github.com/fatih/structtag)](https://pkg.go.dev/github.com/fatih/structtag)

structtag provides a way of parsing and manipulating struct tag Go fields. It's used by tools like [gomodifytags](https://github.com/fatih/gomodifytags). For more examples, checkout [the projects using structtag](https://pkg.go.dev/github.com/fatih/structtag?tab=importedby).

# Install

```bash

go get github.com/fatih/structtag

```

# Example

```go

package main

import (

	"fmt"

	"reflect"

	"sort"

	"github.com/fatih/structtag"

)

func main() {

	type t struct {

		t string `json:"foo,omitempty,string" xml:"foo"`

	}

	// get field tag

	tag := reflect.TypeOf(t{}).Field(0).Tag

	// ... and start using structtag by parsing the tag

	tags, err := structtag.Parse(string(tag))

	if err != nil {

		panic(err)

	}

	// iterate over all tags

	for _, t := range tags.Tags() {

		fmt.Printf("tag: %+v\n", t)

	}

	// get a single tag

	jsonTag, err := tags.Get("json")

	if err != nil {

		panic(err)

	}

	fmt.Println(jsonTag)         // Output: json:"foo,omitempty,string"

	fmt.Println(jsonTag.Key)     // Output: json

	fmt.Println(jsonTag.Name)    // Output: foo

	fmt.Println(jsonTag.Options) // Output: [omitempty string]

	// change existing tag

	jsonTag.Name = "foo_bar"

	jsonTag.Options = nil

	tags.Set(jsonTag)

	// add new tag

	tags.Set(&structtag.Tag{

		Key:     "hcl",

		Name:    "foo",

		Options: []string{"squash"},

	})

	// print the tags

	fmt.Println(tags) // Output: json:"foo_bar" xml:"foo" hcl:"foo,squash"

	// sort tags according to keys

	sort.Sort(tags)

	fmt.Println(tags) // Output: hcl:"foo,squash" json:"foo_bar" xml:"foo"

}

```