See RFC 7396 for a description of Json Merge Patch.
This implementation uses Json.Net to generate and apply a set of changes described in a merge patch document.
Changes can be applied multiple times to different targets and should be okay performance wise.
I compared the speed by applying the same set of changes with the native Json Merge Feature in asp.net nad had similar performance for the first patch, and better timings for subsequent patches.
[HttpPatch]
[Route("resources/{resourceId}", Name="PatchResource")]
public IHttpActionResult PatchResource(string resourceId, [FromBody] JsonMergePatchDocument<Resource> patchDocument) {
var resource = _resourceRepository.Get(resourceId);
if(resource == null) return NotFound();
patchDocument.ApplyPatch(resource);
resourceRepository.Update(resource);
return Request.CreateResponse(HttpStatusCode.NoContent, "No Content");
}- Cleanup error handling.
- Provide Nuget Package.
- Implement Validation for the Patch Document. The modelstate should indicate any validtion problems for properties and components provided by the patch.
- Add
application/merge-patch+jsonMediaType for webapi2 and dotnet core 2.0
If you dont't need RFC 7396 but any Patch format the standard Asp.Net Feature
Morcato has build a RFC 7396 implementation on top of Asp.Net Cores JsonPatch standard feature.
https://github.com/Morcatko/Morcatko.AspNetCore.JsonMergePatch