2 files changed, 67 insertions, 0 deletions
diff --git a/lib/puppet/parser/functions/interface_for_ip.rb b/lib/puppet/parser/functions/interface_for_ip.rb
new file mode 100644
index 0000000..1c67120
--- /dev/null
+++ b/lib/puppet/parser/functions/interface_for_ip.rb
@@ -0,0 +1,33 @@
+require 'ipaddr'
+
+# Custom function to lookup the interface which matches the subnet
+# of the provided IP address.
+# The function iterates over all the interfaces and chooses the
+# first locally assigned interface which matches the IP.
+module Puppet::Parser::Functions
+  newfunction(:interface_for_ip, :type => :rvalue, :doc => "Find the bind IP address for the provided subnet.") do |arg|
+    if arg[0].class == String
+      begin
+        ip_to_find = arg[0]
+        Dir.foreach('/sys/class/net/') do |interface|
+          next if interface == '.' or interface == '..'
+          iface_no_dash = interface.gsub('-', '_')
+          interface_ip = lookupvar("ipaddress_#{iface_no_dash}")
+          netmask = lookupvar("netmask_#{iface_no_dash}")
+          if not interface_ip.nil? then
+            ip1=IPAddr.new(interface_ip)
+            ip2=IPAddr.new(ip_to_find)
+            if ip1.mask(netmask) == ip2.mask(netmask) then
+              return interface
+            end
+          end
+        end
+      rescue JSON::ParserError
+        raise Puppet::ParseError, "Syntax error: #{arg[0]} is invalid"
+      end
+    else
+      raise Puppet::ParseError, "Syntax error: #{arg[0]} is not a String"
+    end
+    return ''
+  end
+end
diff --git a/lib/puppet/parser/functions/local_fence_devices.rb b/lib/puppet/parser/functions/local_fence_devices.rb
new file mode 100644
index 0000000..1ebce67
--- /dev/null
+++ b/lib/puppet/parser/functions/local_fence_devices.rb
@@ -0,0 +1,34 @@
+module Puppet::Parser::Functions
+  newfunction(:local_fence_devices, :arity =>2, :type => :rvalue,
+              :doc => ("Given an array of fence device configs, limit them" +
+                       "to fence devices whose MAC address is present on" +
+                       "some of the local NICs, and prepare a hash which can be" +
+                       "passed to create_resources function")) do |args|
+    agent = args[0]
+    devices = args[1]
+    unless agent.is_a?(String) && agent.length > 0
+      raise Puppet::ParseError, "local_fence_devices: Argument 'agent' must be a non-empty string. The value given was: #{agent_type}"
+    end
+    unless devices.is_a?(Array)
+      raise Puppet::ParseError, "local_fence_devices: Argument 'devices' must be an array. The value given was: #{devices}"
+    end
+
+    # filter by agent type
+    agent_type_devices = devices.select { |device| device['agent'] == agent }
+
+    # filter by local mac address
+    local_devices = agent_type_devices.select do |device|
+      function_has_interface_with(['macaddress', device['host_mac']])
+    end
+
+    # construct a hash for create_resources
+    return local_devices.each_with_object({}) do |device, hash|
+      # disallow collisions
+      if hash[device['host_mac']]
+         raise Puppet::ParseError, "local_fence_devices: Only single fence device per agent per host is allowed. Collision on #{device['host_mac']} for #{agent}"
+      end
+
+      hash[device['host_mac']] = device['params'] || {}
+    end
+  end
+end