Implement web-server

web/server.go

@@ -0,0 +1,78 @@
+package web
+
+import (
+	"encoding/json"
+	"fmt"
+	"image"
+	"image/png"
+	"net/http"
+
+	"git.fjla.uk/fred.boniface/barcodes/generation"
+	"git.fjla.uk/fred.boniface/barcodes/validation"
+	"github.com/boombuler/barcode"
+)
+
+func StartServer() {
+	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		fmt.Fprintf(w, "Barcodes")
+	})
+
+	http.HandleFunc("/generate", generateBarcode)
+
+	port := ":8500"
+	fmt.Printf("Server listening on port %s\n", port)
+
+	err := http.ListenAndServe(port, nil)
+	if err != nil {
+		fmt.Println("Error: ", err)
+	}
+}
+
+func generateBarcode(w http.ResponseWriter, r *http.Request) {
+	var req BarcodeRequest
+	err := json.NewDecoder(r.Body).Decode(&req)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusBadRequest)
+		return
+	}
+
+	parameters := generation.Parameters{
+		Format:   generation.BarcodeType(req.BarcodeType),
+		ECCLevel: generation.ECCLevel(req.ECCLevel),
+		Content:  req.Content,
+	}
+
+	validate := validation.Validate(req.Content, req.BarcodeType)
+	if !validate {
+		fmt.Println("Validation Failed")
+		http.Error(w, "Validation Failed", http.StatusBadRequest)
+		return
+	}
+
+	barcodeGen, err := generation.Generate(parameters)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	if barcodeGen == nil {
+		fmt.Println("Generation failed, no barcode created")
+		http.Error(w, "Barcode Generation Failed", http.StatusInternalServerError)
+		return
+	}
+
+	barcodeGen, _ = barcode.Scale(barcodeGen, req.Width, req.Height)
+
+	image, isImage := barcodeGen.(image.Image)
+	if !isImage {
+		fmt.Println("Generation failed - no image")
+		http.Error(w, "Generated Barcode is not an image", http.StatusInternalServerError)
+		return
+	}
+
+	w.Header().Set("Content-Type", "image/png")
+
+	err = png.Encode(w, image)
+	if err != nil {
+		http.Error(w, "Error streaming barcode", http.StatusInternalServerError)
+	}
+}

web/types.go

@@ -0,0 +1,9 @@
+package web
+
+type BarcodeRequest struct {
+	BarcodeType string `json:"barcode_type"`
+	Width       int    `json:"width"`
+	Height      int    `json:"height"`
+	ECCLevel    int    `json:"ecc_level"`
+	Content     string `json:"content"`
+}