From afe5ed879f7015e62bcf431f0bdf70093af63ca5 Mon Sep 17 00:00:00 2001
From: Bernardo Meurer Costa <beme@anthropic.com>
Date: Tue, 21 Oct 2025 09:02:36 +0000
Subject: [PATCH] feat(libstore): add DELETE method support to FileTransfer

Add support for HTTP DELETE requests to FileTransfer infrastructure:

This enables S3 multipart upload abort functionality via DELETE requests
to S3 endpoints.
---
 src/libstore/filetransfer.cc                   | 8 ++++++++
 src/libstore/include/nix/store/filetransfer.hh | 8 ++++++++
 2 files changed, 16 insertions(+)

diff --git a/src/libstore/filetransfer.cc b/src/libstore/filetransfer.cc
index c2c2a86c4..9fd7a967b 100644
--- a/src/libstore/filetransfer.cc
+++ b/src/libstore/filetransfer.cc
@@ -387,6 +387,9 @@ struct curlFileTransfer : public FileTransfer
             if (request.method == HttpMethod::HEAD)
                 curl_easy_setopt(req, CURLOPT_NOBODY, 1);
 
+            if (request.method == HttpMethod::DELETE)
+                curl_easy_setopt(req, CURLOPT_CUSTOMREQUEST, "DELETE");
+
             if (request.data) {
                 if (request.method == HttpMethod::POST) {
                     curl_easy_setopt(req, CURLOPT_POST, 1L);
@@ -919,6 +922,11 @@ FileTransferResult FileTransfer::upload(const FileTransferRequest & request)
     return enqueueFileTransfer(request).get();
 }
 
+FileTransferResult FileTransfer::deleteResource(const FileTransferRequest & request)
+{
+    return enqueueFileTransfer(request).get();
+}
+
 void FileTransfer::download(
     FileTransferRequest && request, Sink & sink, std::function<void(FileTransferResult)> resultCallback)
 {
diff --git a/src/libstore/include/nix/store/filetransfer.hh b/src/libstore/include/nix/store/filetransfer.hh
index a9ed05dc8..402ee4900 100644
--- a/src/libstore/include/nix/store/filetransfer.hh
+++ b/src/libstore/include/nix/store/filetransfer.hh
@@ -90,6 +90,7 @@ enum struct HttpMethod {
     GET,
     HEAD,
     POST,
+    DELETE,
 };
 
 /**
@@ -148,6 +149,8 @@ struct FileTransferRequest
             return "download";
         case HttpMethod::POST:
             return "upload";
+        case HttpMethod::DELETE:
+            return "delet";
         }
         unreachable();
     }
@@ -221,6 +224,11 @@ struct FileTransfer
      */
     FileTransferResult upload(const FileTransferRequest & request);
 
+    /**
+     * Synchronously delete a resource.
+     */
+    FileTransferResult deleteResource(const FileTransferRequest & request);
+
     /**
      * Download a file, writing its data to a sink. The sink will be
      * invoked on the thread of the caller.