Cannot access Classrooms: 502 Bad Gateway & "Preflight request" error with Education API

shaunanoordin commented 7 years ago

Issue Overview

A Teacher accessing Classrooms will see an error message: There was an error loading the classrooms :(

Console will have errors:
- OPTIONS https://education-api.zooniverse.org/teachers/classrooms/ 502 (Bad Gateway)
- Fetch API cannot load https://education-api.zooniverse.org/teachers/classrooms/. Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'https://lab.wildcamgorongosa.org' is therefore not allowed access. The response had HTTP status code 502. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.
Reported by Milena of OII on this date (Fri 20 Jan 2017). Confirmed that she was able to use all Classroom functionality OK yesterday (Thu 19 Jan 2017). Looks like a recent problem.

First instinct is to assume the Education API server has been overloaded again, but I'm not sure if we've seen this "preflight request" error before.
I'll look into restarting the server by this afternoon but I'll first check if there's any investigation we need to do.

shaunanoordin commented 7 years ago

As @marten pointed out, there was an issue with the database config.
The Education API database was updated, but the corresponding new config file for the Education API service/app wasn't correctly deployed.
Hence, the education service/app (Docker container) on the server couldn't connect to the database, and therefore KOed.

shaunanoordin commented 7 years ago

We now have a new error in the console: OPTIONS https://education-api.zooniverse.org/teachers/classrooms/ 503 (Service Unavailable: Back-end server is at capacity)
And the same Fetch API cannot load https://education-api.zooniverse.org/assignments/. Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'https://lab.wildcamgorongosa.org' is therefore not allowed access. The response had HTTP status code 503. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.
Investigation continues.

shaunanoordin commented 7 years ago

As of 4pm today, I can confirm that Teachers can view/create/edit Classrooms as per usual.

Issue solved.