Move qr-code generation to the API

resource/qrcode.go

@@ -0,0 +1,97 @@
+package resource
+
+import (
+	"context"
+	"net/http"
+	"strconv"
+
+	"github.com/Gleipnir-Technology/nidus-sync/config"
+	nhttp "github.com/Gleipnir-Technology/nidus-sync/http"
+	"github.com/gorilla/mux"
+	"github.com/skip2/go-qrcode"
+)
+
+type qrcodeR struct {
+	router *router
+}
+
+func QRCode(r *router) *qrcodeR {
+	return &qrcodeR{
+		router: r,
+	}
+}
+
+func (res *qrcodeR) Mailer(ctx context.Context, w http.ResponseWriter, r *http.Request) *nhttp.ErrorWithStatus {
+	vars := mux.Vars(r)
+	code := vars["code"]
+	if code == "" {
+		return nhttp.NewBadRequest("There should always be a id")
+	}
+	content := config.MakeURLReport("/mailer/%s", code)
+	return writeQRCode(w, r, content)
+}
+func (res *qrcodeR) Marketing(w http.ResponseWriter, r *http.Request) *nhttp.ErrorWithStatus {
+	content := "https://nidus.cloud"
+	return writeQRCode(w, r, content)
+}
+
+func (res *qrcodeR) Report(w http.ResponseWriter, r *http.Request) *nhttp.ErrorWithStatus {
+	vars := mux.Vars(r)
+	code := vars["code"]
+	if code == "" {
+		return nhttp.NewBadRequest("There should always be a code")
+	}
+	content := config.MakeURLNidus("/report/%s", code)
+	return writeQRCode(w, r, content)
+}
+func writeQRCode(w http.ResponseWriter, r *http.Request, content string) *nhttp.ErrorWithStatus {
+	// Get optional size parameter (default to 256)
+	size := 256
+	if sizeStr := r.URL.Query().Get("size"); sizeStr != "" {
+		var err error
+		size, err = strconv.Atoi(sizeStr)
+		if err != nil {
+			return nhttp.NewBadRequest("Invalid 'size' parameter, must be an integer")
+		}
+	}
+
+	// Get optional error correction level (default to Medium)
+	level := qrcode.Medium
+	if levelStr := r.URL.Query().Get("level"); levelStr != "" {
+		switch levelStr {
+		case "L", "l":
+			level = qrcode.Low
+		case "M", "m":
+			level = qrcode.Medium
+		case "Q", "q":
+			level = qrcode.High
+		case "H", "h":
+			level = qrcode.Highest
+		default:
+			return nhttp.NewBadRequest("Invalid 'level' parameter, must be L, M, Q, or H")
+		}
+	}
+
+	// Generate the QR code
+	var qr *qrcode.QRCode
+	var err error
+	qr, err = qrcode.New(content, level)
+	if err != nil {
+		return nhttp.NewError("Error generating QR code: %w", err)
+	}
+
+	// Set the appropriate content type
+	w.Header().Set("Content-Type", "image/png")
+
+	// Generate PNG and write directly to the response writer
+	png, err := qr.PNG(size)
+	if err != nil {
+		return nhttp.NewError("Error encoding QR code to PNG: %w", err)
+	}
+
+	_, err = w.Write(png)
+	if err != nil {
+		return nhttp.NewError("Error writing response: %w", err)
+	}
+	return nil
+}