karakeep: changing cache dir location away from nix store

nixos/modules/services/web-apps/karakeep.nix

@@ -169,11 +169,15 @@ in
         "karakeep-workers.service"
       ];
       partOf = [ "karakeep.service" ];
-      environment = karakeepEnv;
+      environment = {
+        NEXT_CACHE_DIR = "%C/karakeep";
+      }
+      // karakeepEnv;
       serviceConfig = {
         ExecStart = "${cfg.package}/lib/karakeep/start-web";
         User = "karakeep";
         Group = "karakeep";
+        CacheDirectory = "karakeep";
         StateDirectory = "karakeep";
         EnvironmentFile = environmentFiles;
         PrivateTmp = "yes";

pkgs/by-name/ka/karakeep/package.nix

@@ -80,6 +80,12 @@ stdenv.mkDerivation (finalAttrs: {
     runHook postBuild
   '';
 
+  preInstall = ''
+    # provide a environment variable to override the cache directory
+    # https://github.com/vercel/next.js/discussions/58864
+    patch -p1 -i ${./patches/cache-from-env-not-nix-store.patch}
+  '';
+
   installPhase = ''
     runHook preInstall
 

pkgs/by-name/ka/karakeep/patches/cache-from-env-not-nix-store.patch

@@ -0,0 +1,14 @@
+diff --git a/apps/web/.next/standalone/node_modules/next/dist/server/image-optimizer.js b/apps/web/.next/standalone/node_modules/next/dist/server/image-optimizer.js
+index cba8876..c3d7c43 100644
+--- a/apps/web/.next/standalone/node_modules/next/dist/server/image-optimizer.js
++++ b/apps/web/.next/standalone/node_modules/next/dist/server/image-optimizer.js
+@@ -409,7 +409,8 @@ class ImageOptimizerCache {
+         ]);
+     }
+     constructor({ distDir, nextConfig }){
+-        this.cacheDir = (0, _path.join)(distDir, "cache", "images");
++        const cacheDir = process.env["NEXT_CACHE_DIR"] || (0, _path.join)(distDir, "cache");
++        this.cacheDir = (0, _path.join)(cacheDir, "images");
+         this.nextConfig = nextConfig;
+     }
+     async get(cacheKey) {