Fix discovery of version 4 of oVirt

[jhernand]

Currently this gem tests for the presence of the oVirt engine sending a
request to the following URL:

http://.../engine.ssh.key.txt

This doesn't work with version 4 of the engine, as that path was
removed. In order to support older and newer versions of the engine this
patch modifies the gem so that it checks first the path that works since
version 3.5 of the engine, and then, if that doesn't work, the old path.

https://bugzilla.redhat.com/1382732

[Fryguy]

It might be cleaner to use .detect

def engine_ssh_public_key
  CANDIDATE_SSH_PUBLIC_KEY_PATHS.detect do |path|
    begin
      key = RestClient::Resource.new("#{base_uri}#{path}", resource_options).get
      key.present?
    rescue RestClient::ResourceNotFound, NoMethodError
      false # Do nothing, just try the next candidate.
    end
  end
end

[jhernand]

Not 100% sure how detect works, but my understanding is that in this case it would return the first path that passes the test, and what we want to do here is to return the key retrieved from that path, not the path itself.

[Fryguy]

Ah fair enough...I misread and mixed up key and path. Carry on :)

[Fryguy]

Do you need the key? or is just the presence of it important?

[Fryguy]

Sorry for the message spam, but what I mean is, if you don't actually need the key itself, then you can keep the detect above and maybe rename the method to engine_ssh_public_key?, then the ovirt? method can be

     def self.ovirt?(options)
        options[:username] = options[:password] = "_unused"
        new(options).engine_ssh_public_key?
     end

[jhernand]

The key isn't needed here, except for the tests: they check that it starts with ssh. That could be changed. However the engine_ssh_public_key is an instance method and isn't marked as private, so I'd say that the original intention was to use the method from outside this class, maybe from the provider. I checked in the provider source code and didn't find any use, but I can't be 100% sure that this isn't used somewhere else. Do you know if this gem is used outside of the provider? I believe it isn't, but I'd appreciate if you can confirm.

[Fryguy]

I don't believe this gem is used outside of the provider, but I don't think there's any real way to know. So, yeah, for SemVer reasons, you'll have to leave it as is, unless you cut a major version.

[jhernand]

I have just verified that this works as expected with oVirt 3.x and oVirt 4.x.

@bdunne, @Fryguy please review/merge, and consider including the change in a new release of the gem.

[bdunne]

Please address the remaining rubocop comments (I suggested a solution to one of the issues). Then we can merge and release a new version. Thanks @jhernand

[bdunne]

You could use let to define these strings then refer to it like a method call in your tests.

let(:base_uri) { "https://nobody.com" }

[bdunne]

@jhernand I'm okay with the unhandled exception rubocop issue since it is well documented.

[jhernand]

@bdunne I addressed your comments in the parts that are relevant for the patch, and introduced another patch in the pull request to address them in the parts that aren't relevant. Hopefully Rubocop will be satisfied now.

[miq-bot]

<github_pr_commenter_batch />Some comments on commits https://github.com/jhernand/ovirt/compare/3f438dea65f71dfa2ae389b73938947eb62e1a3d~...a170624ad8c2b631f29f1899fab426ee84455e67

spec/service_spec.rb

• ⚠️ - 220 - Detected expect_any_instance_of. This RSpec method is highly discouraged, please only use when absolutely necessary.

[miq-bot]

Checked commits https://github.com/jhernand/ovirt/compare/3f438dea65f71dfa2ae389b73938947eb62e1a3d~...a170624ad8c2b631f29f1899fab426ee84455e67 with ruby 2.2.5, rubocop 0.37.2, and haml-lint 0.16.1
2 files checked, 1 offense detected

lib/ovirt/service.rb

• ⚠️ - Line 238, Col 9 - Lint/HandleExceptions - Do not suppress exceptions.

[jhernand]

CF fails to provider discover RHV4.0