LTI checks while OC-Server is not responding

[ssrahn]

• AXIOS has no timeout by default
• Plugin continuously sends new lti requests - page loads continuously
  • It seems there is only a max. number of failed requests - without timeout they wont fail
• No indication on the front-end, it looks like there is a valid connection
• At some point a "CORS Failed" comes through with error code "ERR_NETWORK"
  • But takes a long time
  • Timeout error code would be ECONNABORTED
• Uploading and editing videos is allowed during this time
  • The upload appears as if it hangs on confirmation (Because it also uses a AXIOS request)
  • Editing throws an error immediately

My suggestion:

• Set max value for simultaneous lti check requests
  • It probably only should do one request at a time
• Show Message like "Verbindung zum OpenCast Server wird aufgebaut..." while LTI checks are running
• Disallow Video upload and editing while LTI checks are running (hide or grey out)
  • Or show message in dialog when clicking on upload/edit, explaining that it doesn't work right now
• (Set timeout for AXIOS calls)
  • No timeout wont be a problem if handled correctly. Do we want a timeout?

Could have something to do with #551