AP 547: Add other healthchecks to Geodata

[yzhoubk]

Add http head check to geoservers and spatial servers

[anarchivist]

I think this is a good start but I'd like to see this check be closer in alignment to how OkComputer::Check defines its API. I have some questions about whether some of the classes and methods are necessary. Let me know if you'd like to discuss this further!

[yzhoubk]

@anarchivist I did the updates accordingly, could you please take a look? Thanks

[anarchivist]

Looks good - I think the one other thing I would add are RSpec tests for EndpointUrl and GeoDataHealthCheck::HttpHeadCheck. Then I think this is ready to go!

[yzhoubk]

@anarchivist I've pushed the update, please take a look when you have time. Thanks

[anarchivist]

Almost there. One minor change/clarification; one request for clarification on how the secret file is supposed to work.

[anarchivist]

Why is this necessary? Could we just do the following instead?

Suggested change

	ConnectionFailed = Class.new(StandardError)
	ConnectionFailed = OkComputer::HttpCheck::ConnectionFailed

Alternately, you could omit this line here and modify #perform_request to use the class from OkComputer directly.

[anarchivist]

How is this secret file deployed and what is it supposed to contain? Is there a reason we wouldn't do this with a Docker secret instead? (cc @danschmidt5189)

[anarchivist]

@yzhoubk and i discussed this, and we agreed that we did not have to reuse the existing Docker secret as used by GINGR. The healthchecks do not require authentication. Instead, we should be passing in the values of the complete destination from three environment variables that are settable from the stack file. Example names for each of these could be GEODATA_GEOSERVER_PUBLIC_HEALTHCHECK_URL,  GEODATA_GEOSERVER_SECURE_HEALTHCHECK_URL, and GEODATA_SPATIAL_HEALTHCHECK_URL.

the advantage of this is that this greatly simplifies the setup code here.