从elasticsearch的搜索匹配_source中检索所选属性

In olivere Golang client we have some thing like,

filter := elastic.NewFetchSourceContext(true).Include(authorized_attributes...)
        result1, err := elasticClient.Get().Index(hit.Index).Id(hit.Id).FetchSourceContext(filter).Do(context.TODO())

to filter the _source on selected attributes(here authorized_attributes...is an array of required attributes.

but i want to use official golang client to do this, I know i have to use WithSourceIncludes , but can you provide any examples how to use it.

thanks