JsonPatchOperation on nested property

[marcuslindblom]

How can I patch an object with a nested key that does not exist in the json representation of the document?

This is somewhat what I try to do.

    [Fact]
    public void ShouldPatchDocument()
    {
      using (var store = GetDocumentStore())
      {
        using (var session = store.OpenSession())
        {
          dynamic obj = new ExpandoObject();
          obj.Id = "users/1";
          session.Store(obj);
          session.SaveChanges();
        }

        using (var session = store.OpenSession())
        {
          var jpd = new JsonPatchDocument();
          jpd.Add("/Address/Street", "Sesame Street");
          JsonPatchResult op = store.Operations.Send(new JsonPatchOperation("users/1", jpd));
          Assert.Equal(PatchStatus.Patched, op.Status);
        }
      }
    }

This fails with System.ArgumentException: Cannot reach target location. Failed to fetch 'Address' in path '/Address/Street' for operation 'Add'.

If I add jpd.Add("/Address", new {}); before the Street patch operation the test passes. Is this the preferred way or is it possible to add /Address/Street directly?

[lastav5]

Hi Marcus,

The member you are trying to add to must exist first.
This is according to the RFC (https://datatracker.ietf.org/doc/html/rfc6902#section-4.1):

"For example, an "add" with a target location of "/a/b" starting with this document:

{ "a": { "foo": 1 } }

is not an error, because "a" exists, and "b" will be added to its
value. It is an error in this document:

{ "q": { "bar": 2 } }

because "a" does not exist."