Upstream load balance servers

[manics]

Adds support for referencing a set of upstream servers instead of a single backend server: http://nginx.org/en/docs/http/load_balancing.html

New feature, tag 1.2.0

[joshmoore]

Primary issue I see is that there aren't any tests. How feasible do you think they would be? (Not in the next week though)

[manics]

Problem is this role has grown so there are too many options to test thoroughly.

[joshmoore]

Hmmm.... but that leaves this getting more & more difficult to manage. What would be your plan? To split the role? (Are there other roles on galaxy that could supplement this one?)

[manics]

I think this is a case where the IDR needs a lot of specific functionality from nginx which has to be configured in one go, whereas all our other uses are fairly simple (straight-forward proxying)- so maybe a simple role for general use and a seperate IDR one?

[joshmoore]

Not sure. I can imagine wanting to balance 2 OMERO.webs on the open-source side quite soon.

[manics]

We should scope this out properly then, since there have only been two use cases so far:

• IDR
• web-proxy

[manics]

How should we proceed?

[joshmoore]

I'm fine with getting this in now. My preference would be that we consider this the "one role to rule them all" and we find a way to add tests in the future.