WRP %s

// // WRP - Web Rendering Proxy // // Copyright (c) 2013-2018 Antoni Sawicki // Copyright (c) 2019 Google LLC // package main import ( "bytes" "context" "flag" "fmt" _ "image" "image/gif" "image/png" "log" "net/http" "net/url" "os" "strconv" "time" "github.com/chromedp/cdproto/emulation" "github.com/chromedp/cdproto/cdp" "github.com/chromedp/cdproto/dom" "github.com/chromedp/chromedp" ) var ( ctx context.Context cancel context.CancelFunc gifbuf bytes.Buffer ) func pageServer(out http.ResponseWriter, req *http.Request) { req.ParseForm() furl := req.Form["url"] var gourl string if len(furl) >= 1 && len(furl[0]) > 4 { gourl = furl[0] } else { gourl = "https://en.wikipedia.org/wiki/" } log.Printf("%s Page Reqest for %s URL=%s\n", req.RemoteAddr, req.URL.Path, gourl) out.Header().Set("Content-Type", "text/html") fmt.Fprintf(out, "\nWRP %s\n", gourl) fmt.Fprintf(out, "

\n") if len(gourl) > 4 { capture(gourl, out) } fmt.Fprintf(out, "\n\n") } func imgServer(out http.ResponseWriter, req *http.Request) { log.Printf("%s Img Reqest for %s\n", req.RemoteAddr, req.URL.Path) out.Header().Set("Content-Type", "image/gif") out.Header().Set("Content-Length", strconv.Itoa(len(gifbuf.Bytes()))) out.Write(gifbuf.Bytes()) } func haltServer(out http.ResponseWriter, req *http.Request) { log.Printf("%s Shutdown request received [%s]\n", req.RemoteAddr, req.URL.Path) out.Header().Set("Content-Type", "text/plain") fmt.Fprintf(out, "WRP Shutdown") out.(http.Flusher).Flush() cancel() os.Exit(0) } func capture(gourl string, out http.ResponseWriter) { var nodes []*cdp.Node ctxx := chromedp.FromContext(ctx) var scrcap []byte var loc string log.Printf("Caputure Request for %s\n", gourl) chromedp.Run(ctx, emulation.SetDeviceMetricsOverride(1024, 768, 1.0, false), chromedp.Navigate(gourl), chromedp.Sleep(time.Second*2), chromedp.CaptureScreenshot(&scrcap), chromedp.Location(&loc), chromedp.Nodes("a", &nodes, chromedp.ByQueryAll)) log.Printf("Landed on: %s, Got %d nodes\n", loc, len(nodes)) img, err := png.Decode(bytes.NewReader(scrcap)) if err != nil { log.Printf("Failed to decode screenshot: %s\n", err) fmt.Fprintf(out, "
Unable to decode page screenshot:
%s
\n", err) return } gifbuf.Reset() err = gif.Encode(&gifbuf, img, nil) if err != nil { log.Printf("Failed to encode GIF: %s\n", err) fmt.Fprintf(out, "
Unable to encode GIF:
%s
\n", err) return } base, _ := url.Parse(loc) fmt.Fprintf(out, " $\"wrp\"$ \n\n") for _, n := range nodes { b, err := dom.GetBoxModel().WithNodeID(n.NodeID).Do(cdp.WithExecutor(ctx, ctxx.Target)) if err != nil { continue } tgt, err := base.Parse(n.AttributeValue("href")) if err != nil { continue } target := fmt.Sprintf("/?url=%s", tgt) if len(b.Content) > 6 && len(target) > 7 { fmt.Fprintf(out, "\n", b.Content[0], b.Content[1], b.Content[4], b.Content[5], n.AttributeValue("href"), n.AttributeValue("href"), target) } } fmt.Fprintf(out, "\n") log.Printf("Done with caputure for %s\n", gourl) } func main() { ctx, cancel = chromedp.NewContext(context.Background()) defer cancel() var addr string flag.StringVar(&addr, "l", ":8080", "Listen address:port, default :8080") flag.Parse() http.HandleFunc("/", pageServer) http.HandleFunc("/wrp.gif", imgServer) http.HandleFunc("/favicon.ico", http.NotFound) http.HandleFunc("/halt", haltServer) log.Printf("Starting http server on %s\n", addr) http.ListenAndServe(addr, nil) }