Pdf files on same server don't show onebox with subdomain url

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AI-generated summary

Rocancourt is trying to display a onebox for local PDF files with URLs on a subdomain. However, the onebox only works with domains, not subdomains, even with internal hosts whitelisted. After investigating the code, Rocancourt suspects the issue lies in the external_onebox method, where there is no mention of the whitelist. Further testing reveals that the problem is actually due to the subdomain not using HTTPS. Once the subdomain is switched to non-HTTPS, the onebox displays correctly, resolving the issue Rocancourt.

1

Hi,

Firstly, congratulation for this open source project.

I want make clean display for local pdf files with onebox. I saw that is not to possible with attachment, so i link pdf files from url on same server.

With or without whitelist internal hosts, That work with domains but i don’t see onebox for pdf files from subdomains url (my discourse url is on a subdomain). For my tests, All domains/subdomains redirect on the same server.

discourse
discourse1504×673 98.6 KB

(On test screen, only domains display onebox)

I have read some posts about this, but i don’t understand the problem :

https://meta.discourse.org/t/onebox-domains-whitelist-and-subdomains/40884

How i can fix it ?

Thanks,

PS : Link work for subdomain, i can see pdf file, that’s just display problem for onebox on content.

2

I have search in the code,

 def self.external_onebox(url)
Rails.cache.fetch(onebox_cache_key(url), expires_in: 1.day) do
  fd = FinalDestination.new(url, ignore_redirects: ignore_redirects, ignore_hostnames: blacklisted_domains, force_get_hosts: force_get_hosts)
  uri = fd.resolve
  return blank_onebox if uri.blank? || blacklisted_domains.map { |hostname| uri.hostname.match?(hostname) }.any?

  options = {
    cache: {},
    max_width: 695,
    sanitize_config: Sanitize::Config::DISCOURSE_ONEBOX
  }

  options[:cookie] = fd.cookie if fd.cookie

  if Rails.env.development? && SiteSetting.port.to_i > 0
    Onebox.options = { allowed_ports: [80, 443, SiteSetting.port.to_i] }
  end

  r = Onebox.preview(uri.to_s, options)

  { onebox: r.to_s, preview: r&.placeholder_html.to_s }
end

I think the problem is here, no mention for the whitelist ?

return blank_onebox if uri.blank? || blacklisted_domains.map { |hostname| uri.hostname.match?(hostname) }.any?

This link don’t work too, https can be is the problem ?

Thanks,

3

Finally, the subdomain without https is the problem.

My post is resolved :slight_smile: