115 lines
2.8 KiB
Go
115 lines
2.8 KiB
Go
package web
|
|
|
|
import (
|
|
"encoding/json"
|
|
"errors"
|
|
"fmt"
|
|
"image"
|
|
"image/png"
|
|
"net/http"
|
|
|
|
"git.fjla.uk/fred.boniface/barcodes/generation"
|
|
"git.fjla.uk/fred.boniface/barcodes/validation"
|
|
"github.com/boombuler/barcode"
|
|
)
|
|
|
|
// Generates a barcode from the data and options provided in the request
|
|
func generateBarcode(w http.ResponseWriter, r *http.Request) {
|
|
|
|
if r.Method != http.MethodPost && r.Method != http.MethodGet {
|
|
http.Error(w, "Use a POST or GET request for barcode generation. See the help page for more information", http.StatusMethodNotAllowed)
|
|
return
|
|
}
|
|
|
|
var req *BarcodeRequest
|
|
var err error
|
|
|
|
if r.Method == http.MethodGet {
|
|
req, err = generateFromGet(r)
|
|
if err != nil {
|
|
http.Error(w, err.Error(), http.StatusBadRequest)
|
|
return
|
|
}
|
|
} else {
|
|
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(parameters)
|
|
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, int(req.Width), int(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)
|
|
}
|
|
}
|
|
|
|
func generateFromGet(r *http.Request) (*BarcodeRequest, error) {
|
|
//var parameters generation.Parameters
|
|
if r.Method == http.MethodGet {
|
|
validTypes := map[string]bool{
|
|
"qr": true,
|
|
"aztec": true,
|
|
"datamatrix": true,
|
|
}
|
|
|
|
typeParam := r.URL.Query().Get("type")
|
|
content := r.URL.Query().Get("text")
|
|
|
|
if typeParam == "" || content == "" {
|
|
return nil, errors.New("both 'type' and 'text' parameters are required")
|
|
}
|
|
|
|
if !validTypes[typeParam] {
|
|
return nil, errors.New("'type' must be 'qr', 'aztec', or 'datamatrix'")
|
|
}
|
|
|
|
barcodeReq := &BarcodeRequest{
|
|
BarcodeType: typeParam,
|
|
Width: 300,
|
|
Height: 300,
|
|
ECCLevel: 2,
|
|
Content: content,
|
|
}
|
|
|
|
return barcodeReq, nil
|
|
} else {
|
|
return nil, errors.New("incorrect request type passed to function")
|
|
}
|
|
}
|