pull-through dist server

cmd/dkl-local-server/boot-img.go

@@ -109,7 +109,7 @@ func qemuImgBootImg(format string) func(out io.Writer, ctx *renderContext) (err
 var grubSupportVersion = flag.String("grub-support", "1.1.0", "GRUB support version")
 
 func setupBootImage(bootImg *os.File, ctx *renderContext) (err error) {
-	path, err := ctx.distFetch("grub-support", *grubSupportVersion)
+	path, err := distFetch("grub-support", *grubSupportVersion)
 	if err != nil {
 		return
 	}

cmd/dkl-local-server/boot-tar.go

@@ -31,7 +31,7 @@ func buildBootTar(out io.Writer, ctx *renderContext) (err error) {
 	}
 
 	// kernel
-	kernelPath, err := ctx.distFetch("kernels", ctx.Host.Kernel)
+	kernelPath, err := distFetch("kernels", ctx.Host.Kernel)
 	if err != nil {
 		return
 	}
@@ -92,7 +92,7 @@ func buildBootEFITar(out io.Writer, ctx *renderContext) (err error) {
 	}
 
 	// kernel
-	kernelPath, err := ctx.distFetch("kernels", ctx.Host.Kernel)
+	kernelPath, err := distFetch("kernels", ctx.Host.Kernel)
 	if err != nil {
 		return
 	}

cmd/dkl-local-server/bootv2.go

@@ -42,7 +42,7 @@ func buildInitrd(out io.Writer, ctx *renderContext) (err error) {
 	cat := cpiocat.New(out)
 
 	// initrd
-	initrdPath, err := ctx.distFetch("initrd", ctx.Host.Initrd)
+	initrdPath, err := distFetch("initrd", ctx.Host.Initrd)
 	if err != nil {
 		return
 	}
@@ -54,7 +54,7 @@ func buildInitrd(out io.Writer, ctx *renderContext) (err error) {
 		case "modules":
 
 			layerVersion := ctx.Host.Versions[layer]
-			modulesPath, err := ctx.distFetch("layers", layer, layerVersion)
+			modulesPath, err := distFetch("layers", layer, layerVersion)
 			if err != nil {
 				return err
 			}
@@ -165,7 +165,7 @@ func buildBootstrap(out io.Writer, ctx *renderContext) (err error) {
 			return fmt.Errorf("layer %q not mapped to a version", layer)
 		}
 
-		outPath, err := ctx.distFetch("layers", layer, layerVersion)
+		outPath, err := distFetch("layers", layer, layerVersion)
 		if err != nil {
 			return err
 		}

cmd/dkl-local-server/kernel.go

@@ -8,7 +8,7 @@ import (
 )
 
 func renderKernel(w http.ResponseWriter, r *http.Request, ctx *renderContext) error {
-	path, err := ctx.distFetch("kernels", ctx.Host.Kernel)
+	path, err := distFetch("kernels", ctx.Host.Kernel)
 	if err != nil {
 		return err
 	}
@@ -19,7 +19,7 @@ func renderKernel(w http.ResponseWriter, r *http.Request, ctx *renderContext) er
 }
 
 func fetchKernel(out io.Writer, ctx *renderContext) (err error) {
-	path, err := ctx.distFetch("kernels", ctx.Host.Kernel)
+	path, err := distFetch("kernels", ctx.Host.Kernel)
 	if err != nil {
 		return err
 	}

cmd/dkl-local-server/main.go

@@ -72,7 +72,7 @@ func main() {
 	staticHandler := http.FileServer(http.FS(dlshtml.FS))
 	http.Handle("/favicon.ico", staticHandler)
 	http.Handle("/ui/", staticHandler)
-	http.Handle("/dist/", http.StripPrefix("/dist/", http.FileServer(http.Dir(*dataDir+"/dist"))))
+	http.Handle("/dist/", http.StripPrefix("/dist/", upstreamServer{}))
 
 	http.Handle("/public-state", streamsse.StreamHandler(wPublicState))
 	http.Handle("/state", requireAdmin(streamsse.StreamHandler(wState)))

cmd/dkl-local-server/render-context.go

@@ -138,7 +138,7 @@ func (ctx *renderContext) render(templateText string) (ba []byte, err error) {
 	return
 }
 
-func (ctx *renderContext) distFilePath(path ...string) string {
+func distFilePath(path ...string) string {
 	return filepath.Join(append([]string{*dataDir, "dist"}, path...)...)
 }
 

cmd/dkl-local-server/upstream.go

@@ -9,9 +9,11 @@ import (
 	"log"
 	"net/http"
 	"os"
+	"path"
 	gopath "path"
 	"path/filepath"
 	"strconv"
+	"strings"
 	"time"
 
 	"github.com/dustin/go-humanize"
@@ -22,8 +24,22 @@ var (
 	upstreamURL = flag.String("upstream", "https://dkl.novit.io/dist", "Upstream server for dist elements")
 )
 
-func (ctx *renderContext) distFetch(path ...string) (outPath string, err error) {
+type upstreamServer struct{}
-	outPath = ctx.distFilePath(path...)
+
+func (_ upstreamServer) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	path := path.Clean(req.URL.Path)
+	outPath, err := distFetch(strings.Split(path, "/")...)
+	if err != nil {
+		w.WriteHeader(http.StatusBadGateway)
+		w.Write([]byte(err.Error() + "\n"))
+		return
+	}
+
+	http.ServeFile(w, req, outPath)
+}
+
+func distFetch(path ...string) (outPath string, err error) {
+	outPath = distFilePath(path...)
 
 	if _, err = os.Stat(outPath); err == nil {
 		return