New way to get list of all physical ethernet interfaces

Changes:

* support predictable network interfaces naming based [0]
* better and more reliable way to detect non-virtual, not a wireless ethernet interfaces.
* support old and new Ruby version (1.8.7+)

[0] http://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames

Co-Authored-By: Alexei Sheplyakov <asheplyakov@mirantis.com>

Change-Id: Ia61b23beaef38d3d74bf195d58c1e30dac690b7f
Closes-Bug: #1502198
(cherry picked from commit 3e9d17211d)

agent

@@ -28,6 +28,8 @@ require 'ipaddr'
 require 'rethtool'
 require 'digest'
 require 'timeout'
+# TODO(vsharshov): replace below lines by this string after excluding Ruby 1.8
+require 'pathname'
 
 unless Process.euid == 0
   puts "You must be root"
@@ -268,11 +270,15 @@ class NodeAgent
     begin
       (@os[:network][:interfaces] or {} rescue {}).each do |int, intinfo|
         # Send info about physical interfaces only
-        next if intinfo[:type] !~ /^eth.*/
-        # Exception: eth0.0(example) have "type" => "eth" but it is not physical interface
-        next if int =~ /\d+\.\d+$/ or int =~ /vlan\d+$/
-        # Remove interfaces like eth0.101-hapr, eth1-hapr
-        next if int =~ /\d+-.+/
+
+        next if intinfo[:encapsulation] !~ /^Ethernet.*/
+        # Avoid virtual devices like loopback, tunnels, bonding, vlans ...
+        # TODO(vsharshov): replace below lines by this string after excluding Ruby 1.8
+        # next if File.realpath("/sys/class/net/#{int}") =~ /virtual/
+        next if Pathname.new("/sys/class/net/#{int}").realpath.to_s  =~ /virtual/
+        # Avoid wireless
+        next if File.exist?("/sys/class/net/#{int}/phy80211") ||
+                File.exist?("/sys/class/net/#{int}/wireless")
 
         int_meta = {:name => int}
         int_meta[:state] = intinfo[:state]