Allow returning 200 for root requests

[tmc]

This enables placing deis-router behind a GCE ingress which sends health-checks to /.

[deis-admin]

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[mboersma]

This LGTM--thanks @tmc for doing this. @krancour could you take a look at this too?

[krancour]

I'm not opposed to this, but I'm not entirely clear on why you'd want to do this. The router is, essentially, an ingress controller (although it uses annotated services instead of actual ingress resources because it was created at a time before ingress was stable). Workflow also has support now for "bring your own ingress controller," and you wouldn't include a router in your Workflow installation if you used that option. What I'm not understanding is why one would opt to put an ingress controller in front of the router, since I see those two components as mutually exclusive.

[mboersma]

Jenkins, add to whitelist.

[codecov-io]

Codecov Report

Merging #347 into master will not change coverage. The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #347   +/-   ##
=======================================
  Coverage   56.47%   56.47%           
=======================================
  Files           6        6           
  Lines         425      425           
=======================================
  Hits          240      240           
  Misses        159      159           
  Partials       26       26

Impacted Files	Coverage Δ
nginx/config.go	56.86% <ø> (ø)	:arrow_up:
model/model.go	49.18% <ø> (ø)	:arrow_up:

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[mboersma]

Workflow also has support now for "bring your own ingress controller,"

True, but until some issues are fixed that support is incomplete.

why one would opt to put an ingress controller in front of the router...?

@tmc could you elaborate a bit on the use case for this?

[mboersma]

@tmc we still have some questions about the general usefulness of this change. I'm going to close it since it hasn't gotten attention in a while, but please re-open with some comments if I was too hasty.

Thanks again!