From d9eab2f6d06136f495ba52314db79080d0cbbed6 Mon Sep 17 00:00:00 2001
From: mudler <mudler@c3os.io>
Date: Fri, 10 Feb 2023 21:39:12 +0100
Subject: [PATCH] Wait until download is finished

---
 api/api.go | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/api/api.go b/api/api.go
index 6e822cf..6a60a3b 100644
--- a/api/api.go
+++ b/api/api.go
@@ -6,6 +6,7 @@ import (
 	"net"
 	"net/http"
 	"os"
+	"path/filepath"
 	"regexp"
 	"strings"
 	"sync"
@@ -59,6 +60,9 @@ func (a *API) downloadImage(image, dst string) error {
 	os.MkdirAll(dst, os.ModePerm)
 	a.mu.Unlock()
 
+	os.WriteFile(filepath.Join(dst, ".lock"), []byte{}, 0600)
+	defer os.RemoveAll(filepath.Join(dst, ".lock"))
+
 	pterm.Info.Printfln("Downloading %s to %s", image, dst)
 	ref, err := name.ParseReference(image)
 	if err != nil {
@@ -192,6 +196,10 @@ func (a *API) renderImage(c echo.Context, image, strip string) error {
 		return c.HTML(202, "Processing the request, try again soon.")
 	}
 
+	if _, err := os.Stat(filepath.Join(a.cacheStore.Path(h.Hex), ".lock")); err == nil {
+		return c.HTML(202, "Still processing, try again soon.")
+	}
+
 	pterm.Info.Printfln("Render from cache %s: %s Size: %s", h.Hex, image, units.HumanSize(float64(size)))
 
 	return echo.WrapHandler(