Bots are constantly hitting your site, and a lot of times they're unable to render javascript. Prerender.io is awesome, and allows a headless browser to render you page.
This middleware allows you to intercept requests from crawlers and route them to an external Prerender Service to retrieve the static HTML for the requested page.
Prerender adheres to google's _escaped_fragment_ proposal, which we recommend you use. It's easy:
- Just add <meta name="fragment" content="!"> to the <head> of all of your pages
- If you use hash urls (#), change them to the hash-bang (#!)
- That's it! Perfect SEO on javascript pages.
I tried to replicate the features found in the Prerender-node middleware.
Using it in negroni
package main
import (
"net/http"
"github.com/codegangsta/negroni"
"github.com/tampajohn/prerender"
)
func main() {
n := negroni.New()
n.Use(negroni.NewLogger())
n.Use(prerender.NewOptions().NewPrerender())
n.Use(negroni.NewStatic(http.Dir(".")))
n.Run(":80")
}
... or if you want to use a custom prerender server
package main
import (
"net/http"
"net/url"
"github.com/codegangsta/negroni"
"github.com/tampajohn/prerender"
)
func main() {
n := negroni.New()
n.Use(negroni.NewLogger())
o := prerender.NewOptions()
o.PrerenderURL, _ = url.Parse("http://prerender.powerchord.io/")
n.Use(o.NewPrerender())
n.Use(negroni.NewStatic(http.Dir(".")))
n.Run(":80")
}
... or if you want to use it without negroni
package main
import (
"net/http"
"github.com/tampajohn/prerender"
)
func main() {
m := http.NewServeMux()
m.HandleFunc("/", prerender.NewOptions().NewPrerender().PreRenderHandler)
http.ListenAndServe(":80", m)
}
... or if you want to use it on a single page application
package main
import (
"net/http"
"net/url"
"os"
"path/filepath"
"github.com/codegangsta/negroni"
"github.com/tampajohn/prerender"
"github.com/gorilla/mux"
)
type spaHandler struct {
staticPath string
indexPath string
}
func (h spaHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
path, err := filepath.Abs(r.URL.Path)
if err != nil {
http.Error(w, err.Error(), http.StatusBadRequest)
return
}
path = filepath.Join(h.staticPath, path)
_, err = os.Stat(path)
if os.IsNotExist(err) {
http.ServeFile(w, r, filepath.Join(h.staticPath, h.indexPath))
return
} else if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
http.FileServer(http.Dir(h.staticPath)).ServeHTTP(w, r)
}
func main() {
n := negroni.New()
n.Use(negroni.NewLogger())
n.Use(prerender.NewOptions().NewPrerender())
r := mux.NewRouter()
spa := spaHandler{staticPath: "src", indexPath: "index.html"}
r.PathPrefix("/").Handler(spa)
n.UseHandler(r)
n.Run(":8099")
}
I stole almost all of the logic from prerender-node (thanks prerender guys :))
I also want to thank CodeGangsta for creating Negroni and making it so freaking awesome to use.