gojekyll/plugins/redirect_from.go

package plugins

import (
	"bytes"
	"text/template"
)

type jekyllRedirectFromPlugin struct{ plugin }

var redirectTemplate *template.Template

func init() {
	register("jekyll-redirect-from", jekyllRedirectFromPlugin{})
	tmpl, err := template.New("redirect_from").Parse(redirectFromTemplateSource)
	if err != nil {
		panic(err)
	}
	redirectTemplate = tmpl
}

func (p jekyllRedirectFromPlugin) PostReadSite(s Site) error {
	ps := s.Pages()
	addRedirects, err := p.processRedirectFrom(s, ps)
	if err != nil {
		return err
	}
	if err := p.processRedirectTo(s, ps); err != nil {
		return err
	}
	addRedirects()
	return nil
}

func (p jekyllRedirectFromPlugin) processRedirectFrom(s Site, ps []Page) (func(), error) {
	var (
		cfg       = s.Config()
		siteurl   = cfg.AbsoluteURL
		baseurl   = cfg.BaseURL
		prefix    = siteurl + baseurl
		redirects = []func(){}
	)
	addRedirectFrom := func(from string, to Page) {
		f := func() {
			s.AddHTMLPage(from, createRedirectionHTML(prefix+to.URL()), nil)
		}
		redirects = append(redirects, f)
	}
	for _, p := range ps {
		for _, from := range p.FrontMatter().StringArray("redirect_from") {
			addRedirectFrom(from, p)
		}
	}
	return func() {
		for _, f := range redirects {
			f()
		}
	}, nil
}

func (p jekyllRedirectFromPlugin) processRedirectTo(_ Site, ps []Page) error {
	for _, p := range ps {
		sources := p.FrontMatter().StringArray("redirect_to")
		if len(sources) > 0 {
			p.SetContent(createRedirectionHTML(sources[0]))
		}
	}
	return nil
}

func createRedirectionHTML(to string) string {
	r := redirection{to}
	buf := new(bytes.Buffer)
	if err := redirectTemplate.Execute(buf, r); err != nil {
		panic(err)
	}
	return buf.String()
}

type redirection struct {
	To string
}

// Adapted from https://github.com/jekyll/jekyll-redirect-from
const redirectFromTemplateSource = `<!DOCTYPE html>
<html lang="en-US">
  <meta charset="utf-8">
  <title>Redirecting…</title>
  <link rel="canonical" href="{{.To}}">
  <meta http-equiv="refresh" content="0; url={{.To}}">
  <meta name="robots" content="noindex">
  <h1>Redirecting…</h1>
  <a href="{{.To}}">Click here if you are not redirected.</a>
  <script>location="{{.To}}"</script>
</html>`
Emulate jekyll-redirect-from plugin 2017-07-09 01:57:41 +02:00			`package plugins`

			`import (`
			`"bytes"`
docs 2017-07-09 03:41:35 +02:00			`"text/template"`
Emulate jekyll-redirect-from plugin 2017-07-09 01:57:41 +02:00			`)`

Consolidate plugin interfaces 2017-07-09 04:47:50 +02:00			`type jekyllRedirectFromPlugin struct{ plugin }`
Emulate jekyll-redirect-from plugin 2017-07-09 01:57:41 +02:00
			`var redirectTemplate *template.Template`

			`func init() {`
Consolidate plugin interfaces 2017-07-09 04:47:50 +02:00			`register("jekyll-redirect-from", jekyllRedirectFromPlugin{})`
Implement jekyll-feed simulation (just page generation) 2017-07-09 07:22:32 +02:00			`tmpl, err := template.New("redirect_from").Parse(redirectFromTemplateSource)`
Emulate jekyll-redirect-from plugin 2017-07-09 01:57:41 +02:00			`if err != nil {`
			`panic(err)`
			`}`
			`redirectTemplate = tmpl`
			`}`

Use go 1.9 type aliases 2017-09-03 18:18:17 +02:00			`func (p jekyllRedirectFromPlugin) PostReadSite(s Site) error {`
			`ps := s.Pages()`
			`addRedirects, err := p.processRedirectFrom(s, ps)`
Fix redirect_to 2017-07-10 21:28:07 +02:00			`if err != nil {`
			`return err`
			`}`
Use go 1.9 type aliases 2017-09-03 18:18:17 +02:00			`if err := p.processRedirectTo(s, ps); err != nil {`
lint 2017-07-10 21:39:17 +02:00			`return err`
			`}`
Use go 1.9 type aliases 2017-09-03 18:18:17 +02:00			`addRedirects()`
Fix redirect_to 2017-07-10 21:28:07 +02:00			`return nil`
			`}`

Use go 1.9 type aliases 2017-09-03 18:18:17 +02:00			`func (p jekyllRedirectFromPlugin) processRedirectFrom(s Site, ps []Page) (func(), error) {`
Fix redirect_to 2017-07-10 21:28:07 +02:00			`var (`
Use go 1.9 type aliases 2017-09-03 18:18:17 +02:00			`cfg = s.Config()`
			`siteurl = cfg.AbsoluteURL`
			`baseurl = cfg.BaseURL`
			`prefix = siteurl + baseurl`
			`redirects = []func(){}`
Fix redirect_to 2017-07-10 21:28:07 +02:00			`)`
Use go 1.9 type aliases 2017-09-03 18:18:17 +02:00			`addRedirectFrom := func(from string, to Page) {`
			`f := func() {`
			`s.AddHTMLPage(from, createRedirectionHTML(prefix+to.URL()), nil)`
			`}`
			`redirects = append(redirects, f)`
Fix redirect_to 2017-07-10 21:28:07 +02:00			`}`
			`for _, p := range ps {`
Move getStringArray -> frontmatter.StringArray 2017-09-03 19:18:26 +02:00			`for _, from := range p.FrontMatter().StringArray("redirect_from") {`
Fix redirect_to 2017-07-10 21:28:07 +02:00			`addRedirectFrom(from, p)`
Emulate jekyll-redirect-from plugin 2017-07-09 01:57:41 +02:00			`}`
			`}`
Use go 1.9 type aliases 2017-09-03 18:18:17 +02:00			`return func() {`
			`for _, f := range redirects {`
			`f()`
			`}`
			`}, nil`
Fix redirect_to 2017-07-10 21:28:07 +02:00			`}`

Use go 1.9 type aliases 2017-09-03 18:18:17 +02:00			`func (p jekyllRedirectFromPlugin) processRedirectTo(_ Site, ps []Page) error {`
Fix redirect_to 2017-07-10 21:28:07 +02:00			`for _, p := range ps {`
Move getStringArray -> frontmatter.StringArray 2017-09-03 19:18:26 +02:00			`sources := p.FrontMatter().StringArray("redirect_to")`
Fix redirect_to 2017-07-10 21:28:07 +02:00			`if len(sources) > 0 {`
Use go 1.9 type aliases 2017-09-03 18:18:17 +02:00			`p.SetContent(createRedirectionHTML(sources[0]))`
Fix redirect_to 2017-07-10 21:28:07 +02:00			`}`
Emulate jekyll-redirect-from plugin 2017-07-09 01:57:41 +02:00			`}`
			`return nil`
			`}`

Use go 1.9 type aliases 2017-09-03 18:18:17 +02:00			`func createRedirectionHTML(to string) string {`
			`r := redirection{to}`
Implement jekyll-feed simulation (just page generation) 2017-07-09 07:22:32 +02:00			`buf := new(bytes.Buffer)`
Use go 1.9 type aliases 2017-09-03 18:18:17 +02:00			`if err := redirectTemplate.Execute(buf, r); err != nil {`
Implement jekyll-feed simulation (just page generation) 2017-07-09 07:22:32 +02:00			`panic(err)`
			`}`
Change Page.content []byte -> string 2017-08-10 15:06:53 +02:00			`return buf.String()`
Implement jekyll-feed simulation (just page generation) 2017-07-09 07:22:32 +02:00			`}`

Use go 1.9 type aliases 2017-09-03 18:18:17 +02:00			`type redirection struct {`
			`To string`
Implement jekyll-feed simulation (just page generation) 2017-07-09 07:22:32 +02:00			`}`

Emulate jekyll-redirect-from plugin 2017-07-09 01:57:41 +02:00			`// Adapted from https://github.com/jekyll/jekyll-redirect-from`
Implement jekyll-feed simulation (just page generation) 2017-07-09 07:22:32 +02:00			const redirectFromTemplateSource = `<!DOCTYPE html>
Emulate jekyll-redirect-from plugin 2017-07-09 01:57:41 +02:00			`<html lang="en-US">`
			`<meta charset="utf-8">`
docs 2017-07-09 03:41:35 +02:00			`<title>Redirecting…</title>`
Change Page.content []byte -> string 2017-08-10 15:06:53 +02:00			`<link rel="canonical" href="{{.To}}">`
			`<meta http-equiv="refresh" content="0; url={{.To}}">`
Emulate jekyll-redirect-from plugin 2017-07-09 01:57:41 +02:00			`<meta name="robots" content="noindex">`
docs 2017-07-09 03:41:35 +02:00			`<h1>Redirecting…</h1>`
Change Page.content []byte -> string 2017-08-10 15:06:53 +02:00			`<a href="{{.To}}">Click here if you are not redirected.</a>`
			`<script>location="{{.To}}"</script>`
Emulate jekyll-redirect-from plugin 2017-07-09 01:57:41 +02:00			</html>`