Course Import - Importing a file that is .gz but not .tar.gz hangs page

[kdmccormick]

Reproduction

• Make a .gz file on your computer. Or just rename one of your OLX archives from blah.tar.gz to blah.gz.
• Create a new course
• Go to "Import"
• Pick blah.gz using the file picker.
• Expected: Either:
  • The interface would show an error along the lines of Unsupported file type: .gz
  • The file picker would forbid me from picking a .gz file in the first place.
• Actual: It lets me upload the non-tar .gz file, and once I do upload it, it hangs forever
• Notice that: if you go to the developer console, you can see that the server does correctly respond with 415 Unsupported Media Type

Screenshot

Severity

Scope: Some course authors (including me)
Impact: Confusion. Easy to workaround once you realize what's happening.