chore: add ability to include custom protoc-gen-go dependency in nix flake (#14728)

scripts/update-flake.sh

@@ -5,6 +5,20 @@ set -eu
 
 cd "$(dirname "${BASH_SOURCE[0]}")/.."
 
+check_and_install() {
+	if ! command -v "$1" &>/dev/null; then
+		echo "$1 is not installed. Attempting to install..."
+		if ! nix-env -iA nixpkgs."$1"; then
+			echo "Failed to install $1. Please install it manually and try again."
+			exit 1
+		fi
+		echo "$1 has been installed successfully."
+	fi
+}
+
+check_and_install jq
+check_and_install nix-prefetch-git
+
 OUT=$(mktemp -d -t nar-hash-XXXXXX)
 
 echo "Downloading Go modules..."
@@ -13,4 +27,14 @@ echo "Calculating SRI hash..."
 HASH=$(go run tailscale.com/cmd/nardump --sri "$OUT/pkg/mod/cache/download")
 sudo rm -rf "$OUT"
 
+echo "Updating go.mod vendorHash"
 sed -i "s#\(vendorHash = \"\)[^\"]*#\1${HASH}#" ./flake.nix
+
+# Update protoc-gen-go sha256
+echo "Updating protoc-gen-go sha256..."
+PROTOC_GEN_GO_REV=$(nix eval --extra-experimental-features nix-command --extra-experimental-features flakes --raw .#proto_gen_go.rev)
+echo "protoc-gen-go version: $PROTOC_GEN_GO_REV"
+PROTOC_GEN_GO_SHA256=$(nix-prefetch-git https://github.com/protocolbuffers/protobuf-go --rev "$PROTOC_GEN_GO_REV" | jq -r .hash)
+sed -i "s#\(sha256 = \"\)[^\"]*#\1${PROTOC_GEN_GO_SHA256}#" ./flake.nix
+
+echo "Flake updated successfully!"