Resolve purely numeric alerts

2 files changed, 88 insertions, 2 deletions

diff --git a/lib/custodian/alerter.rb b/lib/custodian/alerter.rb
index 69de28e..f5caa6a 100644
--- a/lib/custodian/alerter.rb
+++ b/lib/custodian/alerter.rb
@@ -11,6 +11,10 @@ require 'socket'
 #
 #  This class encapsulates the raising and clearing of alerts via Mauve.
 #
+#  There is a helper method to update any alerts with details of whether the
+# affected host is inside/outside the Bytemark network.
+#
+#
 class Alerter
 
 
@@ -68,13 +72,48 @@ class Alerter
 
 
   #
+  # Resolve an IP address
+  #
+  def document_address( address )
+
+    raise ArgumentError, "Address must not be nil" if ( address.nil? )
+
+    begin
+      Resolv.new.getname(address)
+    rescue
+      nil
+    end
+  end
+
+
+
+  #
   # Raise the alert.
   #
   def raise( detail )
 
+    #
+    # Is this alert affecting a machine inside/outside our network
+    #
     inside = expand_inside_bytemark( @details["target_host"] )
 
 
+    #
+    # Document the hostname if the alert relates to an IP address.
+    #
+    resolved = ""
+    if ( ( @details["target_host"] =~ /^([0-9]+)\.([0-9]+)\.([0-9]+)\.([0-9]+)$/ ) ||
+         ( @details["target_host"] =~ /^([0-9a-f:]+)$/ ) )
+
+      resolved = document_address( @details["target_host"] )
+      if ( resolved.nil? )
+        resolved = ""
+      else
+        resolved = "The IP address #{@details["target_host"]} resolves to #{resolved}."
+      end
+    end
+
+
     update = Mauve::Proto::AlertUpdate.new
     update.alert   = []
     update.source  = "custodian"
@@ -90,7 +129,7 @@ class Alerter
 
     alert.subject    = @details['target_host']
     alert.summary    = @details['test_alert']
-    alert.detail     = "#{inside} <p>The #{@details['test_type']} test failed against #{@details['target_host']}: #{detail}</p>"
+    alert.detail     = "#{inside} <p>The #{@details['test_type']} test failed against #{@details['target_host']}: #{detail}</p><p>#{resolved}</p>"
     alert.raise_time = Time.now.to_i
     update.alert << alert
 
@@ -103,8 +142,28 @@ class Alerter
   #
   def clear
 
+    #
+    # Is this alert affecting a machine inside/outside our network
+    #
     inside = expand_inside_bytemark( @details["target_host"] )
 
+
+    #
+    # Document the hostname if the alert relates to an IP address.
+    #
+    resolved = ""
+    if ( ( @details["target_host"] =~ /^([0-9]+)\.([0-9]+)\.([0-9]+)\.([0-9]+)$/ ) ||
+         ( @details["target_host"] =~ /^([0-9a-f:]+)$/ ) )
+
+      resolved = document_address( @details["target_host"] )
+      if ( resolved.nil? )
+        resolved = ""
+      else
+        resolved = "The IP address #{@details["target_host"]} resolves to #{resolved}."
+      end
+    end
+
+
     update = Mauve::Proto::AlertUpdate.new
     update.alert   = []
     update.source  = "custodian"
@@ -121,7 +180,7 @@ class Alerter
 
     alert.subject    = @details['target_host']
     alert.summary    = @details['test_alert']
-    alert.detail     = "#{inside} <p>The #{@details['test_type']} test succeeded against #{@details['target_host']}</p>"
+    alert.detail     = "#{inside} <p>The #{@details['test_type']} test succeeded against #{@details['target_host']}</p><p>#{resolved}</p>"
     alert.clear_time = Time.now.to_i
     update.alert << alert
 
diff --git a/t/test-alerter.rb b/t/test-alerter.rb
index 88dc786..97e19b5 100755
--- a/t/test-alerter.rb
+++ b/t/test-alerter.rb
@@ -92,6 +92,33 @@ class TestAlerter < Test::Unit::TestCase
 
 
 
+  #
+  #  Test documentation-detection.
+  #
+  def test_locations_inside_outside
+
+    obj = Alerter.new( nil )
+
+    assert_raise ArgumentError do
+      obj.document_address( nil )
+    end
+
+    #
+    # IPv6 lookup
+    #
+    details = obj.document_address( "2001:41c8:125:46::22" )
+    assert( details =~ /ssh.steve.org.uk/i )
 
+    #
+    # IPv4 lookup
+    #
+    details = obj.document_address( "80.68.85.48" )
+    assert( details =~ /ssh.steve.org.uk/i )
 
+    #
+    # Bogus lookup - should return nil.
+    #
+    details = obj.document_address( "800.683.853.348" )
+    assert( details.nil? )
+  end
 end