sf_nodeless.rb

# Copyright 2012-2013 The Scale Factory Limited. All rights reserved.

begin
    require 'json'
    require 'net/http'
rescue LoadError
    retry if require 'rubygems'
    raise
end

#################################################################################
# EC2 userdata fact finding

ec2_userdata = Facter.value('ec2_userdata')

if ec2_userdata

    json = JSON.parse( ec2_userdata )

    json.each do |key,val|

        next unless key.start_with?('sf_')

        Facter.add(key) do

            has_weight(10)

            setcode do 
                if json[key].respond_to?('join')
                    json[key].join(',')
                else
                    val
                end
            end

        end

    end

end

#################################################################################
# JSON http response fact finding 

if Facter.value('is_virtual') == 'true'

    begin

        ## Check if we have provided a url for the http endpoint
        if File.exists?( '/etc/sf_nodeless_url' )
            url = File.open('/etc/sf_nodeless_url', 'rb') { |f| f.read }
            uri = URI.parse( url )

            http = Net::HTTP::new( uri.host, uri.port )
            http.open_timeout = 3 # time out connects after 3s
            request = Net::HTTP::Get.new( uri.request_uri )
            response = http.request( request )

            if response.code == "200"

                json = JSON.parse( response.body )

                json.each do |key,val|

                    next unless key.start_with?('sf_')

                    Facter.add(key) do

                        has_weight(10)

                        setcode do 
                            if json[key].respond_to?('join')
                                json[key].join(',')
                            else
                                val
                            end
                        end

                    end

                end

            end

        end

    rescue Exception => e
	# XXX Should we generate an error or log entry here?  No other Facter
	#  code seems to do so, but it might be useful for debugging.
    end

end

#################################################################################
# Fallback facts taken from config files.  These have lower priority so get
#  executed last.

Facter.add("sf_roles") do

    has_weight(100)

    setcode do

        # Determine which config file to use. Use /etc/puppet/sf_roles.conf
        # if that exists. If that doesn't exist, try /etc/sf_roles.conf.

        roles_file = '/etc/sf_roles.conf';
        if File.exists?( '/etc/puppet/sf_roles.conf' )
            roles_file = '/etc/puppet/sf_roles.conf'
        end

        # Read roles from config file, one per line.  Return
        #  then as a comma-separated list

        if File.exists?( roles_file )

            roles = []

            File.open( roles_file, 'r') { |f|

                f.each_line do |line|
                    roles << line.chomp
                end

            }

            roles.join(',')

        end

    end

end


Facter.add("sf_environment") do

    has_weight(100)

    setcode do

        # Determine which config file to use. Use /etc/puppet/sf_environment.conf
        # if that exists. If that doesn't exist, try /etc/sf_location.conf.

        environment_file = '/etc/sf_environment.conf';
        if File.exists?( '/etc/puppet/sf_environment.conf' )
            environment_file = '/etc/puppet/sf_environment.conf'
        end

        # Read environment from config file. There is only one.

        if File.exists?( environment_file )

            environment = nil

            File.open( environment_file, 'r') { |f|
                environment = f.readline.chomp
            }

            environment

        end

    end

end

Facter.add("sf_location") do

    has_weight(100)

    setcode do

        # Determine which config file to use. Use /etc/puppet/sf_location.conf
        # if that exists. If that doesn't exist, try /etc/sf_location.conf.

        location_file = '/etc/sf_location.conf';
        if File.exists?( '/etc/puppet/sf_location.conf' )
            location_file = '/etc/puppet/sf_location.conf'
        end

        # Read location from config file. Again, there is only one.

        if File.exists?( location_file )

            location = nil

            File.open( location_file, 'r') { |f|
                location = f.readline.chomp
            }

            location

        end

    end

end