fix: compiling cloudflare caddy module

actually compile locally since xcaddy is impure

modules/nixos/services/cloudflare.nix

@@ -34,41 +34,6 @@ let
 
   ];
 
-  # Build with Cloudflare plugin for DNS validation
-  # Otherwise, requires HTTPS to be disabled for issuance
-  caddy = pkgs.stdenv.mkDerivation rec {
-    pname = "caddy";
-    version = "latest";
-    dontUnpack = true;
-
-    nativeBuildInputs = with pkgs; [ git go xcaddy ];
-
-    plugins = [
-      "github.com/caddy-dns/cloudflare@a9d3ae2690a1d232bc9f8fc8b15bd4e0a6960eec"
-    ];
-
-    configurePhase = ''
-      export GOCACHE=$TMPDIR/go-cache
-      export GOPATH="$TMPDIR/go"
-    '';
-
-    buildPhase = let
-      pluginArgs =
-        lib.concatMapStringsSep " " (plugin: "--with ${plugin}") plugins;
-    in ''
-      runHook preBuild
-      ${pkgs.xcaddy}/bin/xcaddy build "v${version}" ${pluginArgs}
-      runHook postBuild
-    '';
-
-    installPhase = ''
-      runHook preInstall
-      mkdir -p $out/bin
-      mv caddy $out/bin
-      runHook postInstall
-    '';
-  };
-
 in {
 
   options.cloudflare.enable = lib.mkEnableOption "Use Cloudflare.";
@@ -85,20 +50,29 @@ in {
     }];
 
     # Tell Caddy to use Cloudflare DNS for ACME challenge validation
-    services.caddy.package = caddy;
+    services.caddy.package =
+      (pkgs.callPackage ../../../overlays/custom-caddy.nix {
+        plugins = [ "github.com/caddy-dns/cloudflare" ];
+        # vendorSha256 = "sha256-K9HPZnr+hMcK5aEd1H4gEg6PXAaNrNWFvaHYm5m62JY=";
+      });
     caddy.tlsPolicies = [{
       issuers = [{
         module = "acme";
         challenges = {
-          dns.provider = {
-            name = "cloudflare";
-            api_token = "{env.CF_API_TOKEN}";
+          dns = {
+            provider = {
+              name = "cloudflare";
+              api_token = "{env.CF_API_TOKEN}";
+            };
+            resolvers = [ "1.1.1.1" ];
           };
         };
       }];
     }];
     systemd.services.caddy.serviceConfig.EnvironmentFile =
       config.secrets.cloudflareApi.dest;
+    systemd.services.caddy.serviceConfig.AmbientCapabilities =
+      "CAP_NET_BIND_SERVICE";
 
     # API key must have access to modify Cloudflare DNS records
     secrets.cloudflareApi = {

overlays/custom-caddy.nix

@@ -0,0 +1,55 @@
+{ lib, buildGo118Module, fetchFromGitHub, plugins ? [ ] }:
+let
+  imports = lib.flip lib.concatMapStrings plugins (pkg: "   _ \"${pkg}\"\n");
+  main = ''
+    package main
+    import (
+    	caddycmd "github.com/caddyserver/caddy/v2/cmd"
+    	_ "github.com/caddyserver/caddy/v2/modules/standard"
+    ${imports}
+    )
+    func main() {
+    	caddycmd.Main()
+    }
+  '';
+in buildGo118Module rec {
+  pname = "caddy";
+  version = "2.6.4";
+  runVend = true;
+
+  subPackages = [ "cmd/caddy" ];
+
+  src = fetchFromGitHub {
+    owner = "caddyserver";
+    repo = "caddy";
+    rev = "v${version}";
+    sha256 = "sha256:3a3+nFHmGONvL/TyQRqgJtrSDIn0zdGy9YwhZP17mU0=";
+  };
+
+  vendorSha256 = "sha256:CrHqJcJ0knX+txQ5qvzW4JrU8vfi3FO3M/xtislIC1M=";
+
+  overrideModAttrs = (_: {
+    preBuild = ''
+      echo '${main}' > cmd/caddy/main.go
+      go get github.com/caddy-dns/cloudflare
+    '';
+    postInstall = "cp go.sum go.mod $out/ && ls $out/";
+  });
+
+  postPatch = ''
+    echo '${main}' > cmd/caddy/main.go
+    cat cmd/caddy/main.go
+  '';
+
+  postConfigure = ''
+    cp vendor/go.sum ./
+    cp vendor/go.mod ./
+  '';
+
+  meta = with lib; {
+    homepage = "https://caddyserver.com";
+    description = "Fast, cross-platform HTTP/2 web server with automatic HTTPS";
+    license = licenses.asl20;
+    maintainers = with maintainers; [ Br1ght0ne techknowlogick ];
+  };
+}