S3 adapter: upload with "content-type" and "content-encoding" headers

[HoneyryderChuck]

If I use the S3 adapter provided by the gem, after uploading the file ("sitemap.xml.gz"), when I provide the URL to a sitemap validator (like xml-sitemaps.com/validate-xml-sitemap.html ), there is an error, because the request returns an unexpected content media type: "application/gzip".

This happens because the raw S3 upload does not declare the media type, and this is inferred (either by S3 or fog). I've patched the adapter's write method locally so I could have access to the fog API that allows me to set these:

# lib/sitemap_generator/adapters/s3_adapter.rb#L30
  def write(location, raw_data)
      SitemapGenerator::FileAdapter.new.write(location, raw_data)

      directory.files.create(
        :key    => location.path_in_public,
        :body   => File.open(location.path),
        :public => true,
        "Content-Type" => "application/xml",
        "Content-Encoding" => "gzip"
      )
    end

After uploading with this patch, the sitemap link could be validated.

I'd like to propose either passing headers as a supported option, or to apply these changes to the adapter, depending of whether compression is on or off (for "content-encoding").

[marckohlbrugge]

I'm running into this same issue with Cloudflare R2 which uses the S3 adapter. My sitemap files have the application/x-gzip content-type which seems to confuse Google.

Would you mind making a PR of your suggested change? I think more people would benefit from it.