Raise ConnectionError on most non-200 errors

[matthinea]

Problem

Most methods interface with Elasticsearch via json_request. The json_request method only raises on 5xx errors, or when there's an explicity error key in the JSON response. This leaves 3xx and 4xx errors as silent failures.

Solution

• For post and put methods, raise unless the response code is 2xx.
• For 'get' and 'delete' methods, additionally allow 404 Not Found, since apparently some methods rely on that.

[j1wilmot]

Approach looks good, but should this be grouped with the 5xx handling? Now there are multiple code locations that handle status codes.

[matthinea]

In principal, yes, but core issue is:

• 404 is expected to be valid for get and delete
• all responses should be valid for head
• only 2xx responses should be valid or put or post

Let me take another pass at this and see if it can be simplified without resulting in major changes to the interface.

[matthinea]

Ok it looks like we can get by with just 404 being valid for head, which simplifies things. Let's me test this branch on QA in a downstream application and make sure everything's working.

[matthinea]

Ok, I added some test cases with real-life examples of how & why GET and DELETE should sometimes not error on 404.

I ran some bulk and individual updates on QA documents with this branch and everything seems to be performing good 👍