// PreRenderHandler is a net/http compatible handler that proxies a request to
// the configured Prerender.io URL. All upstream requests are made with an
// Accept-Encoding=gzip header. Responses are provided either uncompressed or
// gzip compressed based on the downstream requests Accept-Encoding header
func (p *Prerender) PreRenderHandler(rw http.ResponseWriter, or *http.Request) {
client := &http.Client{}
req, err := http.NewRequest("GET", p.buildURL(or), nil)
e.Check(err)
if p.Options.Token != "" {
req.Header.Set("X-Prerender-Token", p.Options.Token)
}
req.Header.Set("User-Agent", or.Header.Get("User-Agent"))
req.Header.Set("Content-Type", or.Header.Get("Content-Type"))
req.Header.Set("Accept-Encoding", "gzip")
res, err := client.Do(req)
//fmt.Println(res)
e.Check(err)
rw.Header().Set("Content-Type", res.Header.Get("Content-Type"))
defer res.Body.Close()
//Figure out whether the client accepts gzip responses
doGzip := strings.Contains(or.Header.Get("Accept-Encoding"), "gzip")
isGzip := strings.Contains(res.Header.Get("Content-Encoding"), "gzip")
if doGzip && !isGzip {
// gzip raw response
rw.Header().Set("Content-Encoding", "gzip")
gz := gzip.NewWriter(rw)
defer gz.Close()
io.Copy(gz, res.Body)
gz.Flush()
} else if !doGzip && isGzip {
// gunzip response
gz, err := gzip.NewReader(res.Body)
e.Check(err)
defer gz.Close()
io.Copy(rw, gz)
} else {
// Pass through, gzip/gzip or raw/raw
rw.Header().Set("Content-Encoding", res.Header.Get("Content-Encoding"))
io.Copy(rw, res.Body)
}
}
func Get(connectionVariable string) *mgo.Session {
if session == nil {
var cs string
if strings.HasPrefix(connectionVariable, "mongodb://") {
cs = connectionVariable
} else {
cs = os.Getenv(connectionVariable)
}
var err error
session, err = mgo.Dial(cs)
errors.Check(err)
// http://godoc.org/labix.org/v2/mgo#Session.SetMode
session.SetMode(mgo.Monotonic, true)
}
return session.Copy()
}