(PUP-10039) Add ServerList resolver #7856

melissa · 2019-11-22T21:08:42Z

No description provided.

lib/puppet/http/resolver/serverlist.rb

puppetcla · 2019-11-23T00:00:20Z

CLA signed by all contributors.

lib/puppet/http/resolver/serverlist.rb

melissa · 2019-11-27T00:30:28Z

lib/puppet/http/session.rb

      end
    end

-    errors.each { |e| Puppet.log_exception(e) }
-
+    @resolution_exceptions.each { |e| Puppet.log_exception(e) }
    raise Puppet::HTTP::RouteError, "No more routes to #{name}"


I mucked with the code to play with this a bit more:

I added the ServerList resolver to the CA service, and I removed the raise in the ServerList resolver so that we would fall back to the settings resolver. I also ensured both the SRV and ServerList resolvers return nil if we don't find anything that connects successfully (otherwise we get weird errors when it tries to resolve service.url on line 20, since service is being set to either the array of servers in server_list or an empty array for srv).

be ./bin/puppet agent -t --server_list apple.example.com,google.example.com --use_srv_records --debug

Debug: Resolving service 'ca' using Puppet::HTTP::Resolver::ServerList Debug: Creating new connection for https://apple.example.com:8140 Debug: Starting connection for https://apple.example.com:8140 Debug: Unable to connect to server from server_list setting: Failed to connect to https://apple.example.com:8140/status/v1/simple/master: Failed to open TCP connection to apple.example.com:8140 (getaddrinfo: nodename nor servname provided, or not known) Debug: Creating new connection for https://google.example.com:8140 Debug: Starting connection for https://google.example.com:8140 Debug: Unable to connect to server from server_list setting: Failed to connect to https://google.example.com:8140/status/v1/simple/master: Failed to open TCP connection to google.example.com:8140 (getaddrinfo: nodename nor servname provided, or not known) Debug: Resolving service 'ca' using Puppet::HTTP::Resolver::SRV Debug: Searching for SRV records for domain: Home Debug: Found 0 SRV records for: _x-puppet-ca._tcp.Home Debug: Searching for SRV records for domain: Home Debug: Found 0 SRV records for: _x-puppet._tcp.Home Debug: Resolving service 'ca' using Puppet::HTTP::Resolver::Settings Debug: Creating new connection for https://puppet:8140 Debug: Starting connection for https://puppet:8140 Debug: Connection to https://puppet:8140/puppet-ca/v1 failed, trying next route: Failed to connect to https://puppet:8140/puppet-ca/v1: execution expired Error: Failed to connect to https://apple.example.com:8140/status/v1/simple/master: Failed to open TCP connection to apple.example.com:8140 (getaddrinfo: nodename nor servname provided, or not known) Wrapped exception: Failed to open TCP connection to apple.example.com:8140 (getaddrinfo: nodename nor servname provided, or not known) Error: Failed to connect to https://google.example.com:8140/status/v1/simple/master: Failed to open TCP connection to google.example.com:8140 (getaddrinfo: nodename nor servname provided, or not known) Wrapped exception: Failed to open TCP connection to google.example.com:8140 (getaddrinfo: nodename nor servname provided, or not known) Error: Failed to connect to https://puppet:8140/puppet-ca/v1: execution expired Wrapped exception: execution expired Error: No more routes to ca Error: Could not run: No more routes to ca

lib/puppet/http/resolver/srv.rb

lib/puppet/http/resolver/serverlist.rb

lib/puppet/http/resolver/settings.rb

lib/puppet/http/session.rb

melissa · 2019-12-02T21:41:38Z

@joshcooper I think I addressed all of your comments. I switched this to a real PR from a draft. I think it's ready to go.

lib/puppet/http.rb

spec/unit/http/resolver_spec.rb

This commit adds a resolver that will iterate through an array of servers and return the first in the list that responds successfully to a get connection. We do not yet use this new resolver anywhere, but will switch over to it in the near future. If a port is not provided in the list of servers, it will use a default port. If no functional server is found, we raise an error rather than allowing the session to continue searching other resolvers for a functional server.

Rather than checking a connection is successful as a part of the session, this commit changes to let us check that connection in the resolvers. This is something we needed to do for ServerList, so this change makes that behavior consistent for all other resolvers as well. It also allows us to reduce some complexity. We can now create the service directly from the resolver, rather than having to pass that call down from the resolver, to the session, and finally to the service.

Rather than have both service doubles named the same thing, we need to be able to distinguish them. This way, if something gets messed up and the tests fail, both the name and the object id will be different. They won't look like the same object at first glance.

melissa commented Nov 22, 2019

View reviewed changes