Merge pull request #3 from ashleyprimo/v1.2.1-dev

v1.2.1: Fix Scale + Render of QR codes

go.mod

@@ -13,6 +13,7 @@ require (
 	github.com/cespare/xxhash/v2 v2.1.1 // indirect
 	github.com/golang/protobuf v1.4.3 // indirect
 	github.com/matttproud/golang_protobuf_extensions v1.0.1 // indirect
+	github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646 // indirect
 	github.com/prometheus/client_model v0.2.0 // indirect
 	github.com/prometheus/common v0.26.0 // indirect
 	github.com/prometheus/procfs v0.6.0 // indirect

go.sum

@@ -61,6 +61,8 @@ github.com/modern-go/reflect2 v0.0.0-20180701023420-4b7aa43c6742/go.mod h1:bx2lN
 github.com/modern-go/reflect2 v1.0.1/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
 github.com/mwitkow/go-conntrack v0.0.0-20161129095857-cc309e4a2223/go.mod h1:qRWi+5nqEBWmkhHvq77mSJWrCKwh8bxhgT7d/eI7P4U=
 github.com/mwitkow/go-conntrack v0.0.0-20190716064945-2f068394615f/go.mod h1:qRWi+5nqEBWmkhHvq77mSJWrCKwh8bxhgT7d/eI7P4U=
+github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646 h1:zYyBkD/k9seD2A7fsi6Oo2LfFZAehjjQMERAvZLEDnQ=
+github.com/nfnt/resize v0.0.0-20180221191011-83c6a9932646/go.mod h1:jpp1/29i3P1S/RLdc7JQKbRpFeM1dOBd8T9ki5s+AY8=
 github.com/pkg/errors v0.8.0/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=

qr/border.go

@@ -0,0 +1,31 @@
+package qr
+
+import (
+	"github.com/boombuler/barcode"
+	"image"
+	"image/color"
+)
+
+type WhiteBorder struct {
+	width   int
+	barcode barcode.Barcode
+}
+
+func (wb WhiteBorder) At(x, y int) color.Color {
+	bounds := wb.barcode.Bounds()
+	w := bounds.Dx()
+	h := bounds.Dy()
+	if x < wb.width || x >= w+wb.width || y < wb.width || y >= h+wb.width {
+		return color.White
+	}
+	return wb.barcode.At(x-wb.width, y-wb.width)
+}
+
+func (wb WhiteBorder) Bounds() image.Rectangle {
+	b := wb.barcode.Bounds()
+	return image.Rect(0, 0, b.Dx()+2*wb.width, b.Dy()+2*wb.width)
+}
+
+func (wb WhiteBorder) ColorModel() color.Model {
+	return wb.barcode.ColorModel()
+}

qr/engine.go

@@ -1,19 +1,19 @@
 package qr
 
 import (
-	"fmt"
-	"net"
-	//	"flag"
 	"bytes"
+	"fmt"
+	"image"
 	"image/png"
+	"net"
 	"net/http"
 	"net/url"
 	"strconv"
 
 	"github.com/ashleyprimo/go-qr-generator/initialize"
 
-	"github.com/boombuler/barcode"
 	"github.com/boombuler/barcode/qr"
+
 	log "github.com/sirupsen/logrus"
 )
 
@@ -119,18 +119,19 @@ func Engine(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	// Add border
+	var codeBordered image.Image = WhiteBorder{1, code}
+
 	// Scale the barcode to the appropriate size
-	code, err = barcode.Scale(code, sizeInt, sizeInt)
+	codeScaled, err := scale(codeBordered, uint(sizeInt))
 	if err != nil {
 		InternalServerError(w, r, "Unable to scale QR code.")
 		return
-	} else {
-		log.Debugf("Generated QR Code: %s", code)
 	}
 
 	// Encode PNG
 	buffer := new(bytes.Buffer)
-	if err := png.Encode(buffer, code); err != nil {
+	if err := png.Encode(buffer, codeScaled); err != nil {
 		InternalServerError(w, r, "Unable to encode PNG from code buffer.")
 		return
 	}

qr/scale.go

@@ -0,0 +1,22 @@
+package qr
+
+import (
+	"errors"
+	"image"
+
+	"github.com/nfnt/resize"
+
+	log "github.com/sirupsen/logrus"
+)
+
+func scale(code image.Image, sizeInt uint) (image.Image, error) {
+	log.Debugf("Scaling Image")
+
+	// Resize 'image.Image' to requested size
+	img := resize.Resize(sizeInt, 0, code, resize.NearestNeighbor)
+	if img != nil {
+		return img, nil
+	} else {
+		return nil, errors.New("Failed to resize image")
+	}
+}