feat: add qrcode

src/routes/paste.go

@@ -5,6 +5,7 @@ import (
 	"crypto/rand"
 	"crypto/sha256"
 	"encoding/base64"
+	"fmt"
 	"io"
 	"io/ioutil"
 	"net/http"
@@ -19,6 +20,9 @@ import (
 	"sour.is/x/paste/src/pkg/readutil"
 	"sour.is/x/toolbox/httpsrv"
 	"sour.is/x/toolbox/log"
+
+	"github.com/yeqown/go-qrcode/v2"
+	"github.com/yeqown/go-qrcode/writer/standard"
 )
 
 func init() {
@@ -36,6 +40,8 @@ func init() {
 		{Name: "getPaste", Method: "GET", Pattern: "/api/{id}", HandlerFunc: p.getPaste},
 		{Name: "getPaste", Method: "GET", Pattern: "/api/get/{id}", HandlerFunc: p.getPaste},
 		{Name: "postPaste", Method: "POST", Pattern: "/api", HandlerFunc: p.postPaste},
+
+		{Name: "qrcode", Method: "GET", Pattern: "/qr", HandlerFunc: p.qrcode},
 	})
 }
 
@@ -119,6 +125,25 @@ func chkGone(path string) bool {
 	return false
 }
 
+type noop struct {
+	io.Writer
+}
+
+func (noop) Close() error { return nil }
+
+func (p *Paste) qrcode(w http.ResponseWriter, r *http.Request) {
+	qrc, err := qrcode.New(r.URL.Query().Get("u"))
+	if err != nil {
+		w.WriteHeader(http.StatusUnprocessableEntity)
+		fmt.Fprintf(w, "could not generate QRCode: %v", err)
+		return
+	}
+
+	wr := standard.NewWithWriter(noop{w}, standard.WithCircleShape())
+	w.WriteHeader(http.StatusOK)
+	_ = qrc.Save(wr)
+}
+
 func (p *Paste) getRandom(w http.ResponseWriter, _ *http.Request) {
 	s := make([]byte, p.randBytes)
 	_, _ = rand.Read(s)