Moved parser code into its own file, and updated main script + test suite to use it.

1 files changed, 451 insertions, 0 deletions

diff --git a/lib/custodian/parser.rb b/lib/custodian/parser.rb
new file mode 100755
index 0000000..a5ce584
--- /dev/null
+++ b/lib/custodian/parser.rb
@@ -0,0 +1,451 @@
+
+require 'beanstalk-client'
+require 'getoptlong'
+require 'json'
+require 'net/http'
+require 'net/https'
+require 'uri'
+
+
+
+
+
+
+
+
+#
+# This is a simple class which will parse a sentinel configuration file.
+#
+# Unlike Sentinel it is not using a real parser, instead it peels off lines
+# via a small number of very simple regular expressions - this should be flaky,
+# but in practice it manages to successfully parse each of the configuration
+# files that we currently maintain @ Bytemark.
+#
+# TODO:
+#
+#   1. Explicitly abort and panic on malformed lines.
+#
+#
+# Steve
+# --
+#
+class MonitorConfig
+
+  #
+  # A hash of macros we found.
+  #
+  attr_reader :MACROS
+
+  #
+  # A handle to the beanstalkd queue.
+  #
+  attr_reader :queue
+
+  #
+  # The filename that we're going to parse.
+  #
+  attr_reader :filename
+
+  #
+  # Timeout period, in seconds, that we encode into test objects.
+  #
+  attr_reader :timeout
+
+
+
+  #
+  # Constructor
+  #
+  def initialize( filename )
+
+
+    @MACROS  = Hash.new()
+    @queue   = Beanstalk::Pool.new(['127.0.0.1:11300'])
+    @file    = filename
+    @timeout = 3
+
+    raise ArgumentError, "Missing configuration file!" if ( @file.nil? )
+    raise ArgumentError, "File not found: #{@file}" unless ( File.exists?( @file) )
+  end
+
+
+  def get_timeout()
+    @timeout
+  end
+
+  def set_timeout( new_val )
+    @timeout = new_val
+  end
+
+
+  #
+  # Retrieve a HTTP page from the web - this is used for macro-expansion
+  #
+  # NOTE:  This came from sentinel.
+  #
+  def getURL (uri_str)
+    begin
+      uri_str = 'http://' + uri_str unless uri_str.match(/^http/)
+      url = URI.parse(uri_str)
+      http = Net::HTTP.new(url.host, url.port)
+      http.open_timeout = @timeout
+      http.read_timeout = @timeout
+
+      if (url.scheme == "https")
+        http.use_ssl = true
+        http.verify_mode = OpenSSL::SSL::VERIFY_NONE
+      end
+
+      response = nil
+
+      if nil == url.query
+        response = http.start { http.get(url.path) }
+      else
+        response = http.start { http.get("#{url.path}?#{url.query}") }
+      end
+
+
+      if ( response.code.to_i != 200 )
+        puts "Status code of #{uri_str} was #{response.code}"
+        puts "ABORTING"
+        exit( 0 )
+      end
+
+      case response
+      when Net::HTTPRedirection
+      then
+        newURL = response['location'].match(/^http/)?
+        response['Location']:uri_str+response['Location']
+        return( getURL(newURL) )
+      else
+        return response.body
+      end
+
+    rescue Errno::EHOSTUNREACH => ex
+      raise ex, "no route to host"
+    rescue Timeout::Error => ex
+      raise ex, "timeout"
+    rescue Errno::ECONNREFUSED => ex
+      raise ex, "connection refused"
+    end
+  end
+
+
+
+  #
+  #  Define a macro, from the configuration file.
+  #
+  def define_macro( line )
+    name = nil
+    val  = Array.new
+
+    #
+    #  Get the name
+    #
+    name = $1.dup if ( line =~ /^([1-2A-Z_]+)\s+/ )
+
+
+    #
+    #  Get the value
+    #
+    if ( line =~ /fetched\s+from\s+(.*)[\r\n\.]*$/ )
+
+      #
+      #  HTTP-fetch
+      #
+      uri = $1.dup.chomp(".")
+
+      text = getURL(uri)
+      text.split( /[\r\n]/ ).each do |line|
+        val.push( line ) if ( line.length() > 0)
+      end
+
+    elsif ( line =~ /\s(is|are)\s+(.*)\.+$/ )
+
+      #
+      #  Literal list of hosts
+      #
+      hosts = $2.dup
+
+      #
+      #  If there is " and " then tokenize
+      #
+      if ( hosts =~ /\s+and\s+/ )
+        tmp = hosts.split( /\s+and\s+/ )
+        tmp.each do |entry|
+          val.push( entry )
+        end
+      else
+        #
+        # Otherwise a single host
+        #
+        val.push( hosts )
+      end
+
+
+    end
+
+    @MACROS[name] = val
+  end
+
+
+
+
+  #
+  #  Return a hash of our current macro-definitions.
+  #
+  #  This is used only by the test-suite.
+  #
+  def macros
+    @MACROS
+  end
+
+
+
+
+  #
+  # Is the given string of text a macro?
+  #
+  def is_macro?( name )
+    !(@MACROS[name]).nil?
+  end
+
+
+
+  #
+  # Return an array of hosts if the given string was a macro identifier.
+  #
+  def get_macro_targets( name )
+    @MACROS[name]
+  end
+
+
+
+
+  #
+  # Parse a single line from the configuration file.
+  #
+  def parse_line( line )
+
+    line.chomp! if ( !line.nil? )
+
+    #
+    # A blank line, or a comment may be skipped.
+    #
+    return nil if ( ( line.nil? ) || ( line =~ /^#/ ) || ( line.length < 1 ) )
+
+    #
+    # The specification of mauve-server to which we should raise our alerts to.
+    #
+    return nil if ( line =~ /Mauve\s+server(.*)source/ )
+
+
+    #
+    #  Look for macro definitions, inline
+    #
+    if ( line =~ /^([0-9A-Z]_+)\s+are\s+fetched\s+from\s+([^\s]+)\.?/ )
+      define_macro( line )
+
+    elsif ( line =~ /^([0-9A-Z_]+)\s+(is|are)\s+/ )
+      define_macro( line )
+
+    elsif ( line =~ /(.*)\s+must\s+ping(.*)/ )
+
+      #
+      #  Ping is a special case because the configuration file entry
+      # would read:
+      #
+      #  $FOO must ping otherwise ...
+      #
+      #  All other tests are of the form:
+      #
+      #  $FOO must run XXX ... otherwise ...
+      #
+      #  If we clevery rewrite the line into:
+      #
+      #  ... must run ping ...
+      #
+      #  We can avoid duplicating the macro-expansion, etc.
+      #
+      pre  = $1.dup
+      post = $2.dup
+      new_line = "#{pre} must run ping #{post}"
+      return( parse_line( new_line ) )
+
+    elsif ( line =~ /\s+must\s+run\s+([^\s]+)(\s+|\.)/i )
+
+      #
+      # Get the service we're testing, and remove any trailing "."
+      #
+      # This handles the case of:
+      #
+      #  LINN_HOSTS must run ssh.
+      #
+      service = $1.dup
+      service.chomp!(".")
+
+      #
+      #  Target of the service-test.
+      #
+      targets = Array.new
+      target  = line.split( /\s+/)[0]
+
+      #
+      #  If the target is a macro then get the list of hosts to
+      # which the test will apply.
+      #
+      if ( is_macro?( target ) )
+        targets = get_macro_targets( target )
+      else
+
+        #
+        # Otherwise a list of one, literal, entry.
+        #
+        targets.push( target )
+      end
+
+      #
+      #  Alert text will have a default, which may be overridden.
+      #
+      alert = "#{service} failed"
+      if ( line =~ /otherwise '([^']+)'/ )
+        alert=$1.dup
+      end
+
+      #
+      # All our service tests, except ping, require a port - we setup the defaults here,
+      # but the configuration file will allow users to specify an alternative
+      # via " on XXX ".
+      #
+      case service
+      when /ssh/ then
+        port=22
+      when /jabber/ then
+        port=5222
+      when /ldap/ then
+        port=389
+      when /^https$/ then
+        port=443
+      when /^http$/ then
+        port=80
+      when /rsync/i then
+        port=873
+      when /ftp/i then
+        port=21
+      when /telnet/i then
+        port=23
+      when /smtp/i then
+        port=25
+      when /dns/i then
+        port=53
+      end
+
+      #
+      # Allow the port to be changed, for example:
+      #
+      #  must run ssh  on   33 otherwise ..
+      #  must run ftp  on   44 otherwise ..
+      #  must run http on 8000 otherwise ..
+      #
+      if ( line =~ /\s+on\s+([0-9]+)/ )
+        port = $1.dup
+      end
+
+
+      ret = Array.new()
+
+      #
+      # For each host in our possibly-macro-expanded list:
+      #
+      targets.each do |host|
+
+        #
+        # The test we'll apply.
+        #
+        test = {
+          :target_host => host,
+          :test_type   => service,
+          :test_port   => port,
+          :test_alert  => alert,
+          :timeout     => @timeout
+        }
+
+
+        #
+        # HTTP-tests will include the expected result in one of two forms:
+        #
+        #    must run http with status 200
+        #
+        #    must run http with content 'text'
+        #
+        # If those are sepcified then include them here.
+        #
+        # Note we're deliberately fast and loose here - which allows both to
+        # be specified:
+        #
+        # http://example.vm/ must run http with status 200 and content 'OK'.
+        #
+        #
+        if ( line =~ /\s+with\s+status\s+([0-9]+)\s+/ )
+          test[:http_status]=$1.dup
+        end
+        if ( line =~ /\s+with\s+content\s+'([^']+)'/ )
+          test[:http_text]=$1.dup
+        end
+
+        #
+        # These are special cased for the DNS types
+        #
+        if ( test[:test_type] =~ /dns/ )
+
+          #
+          #  Sample line:
+          #
+          # DNSHOSTS must run dns for www.bytemark.co.uk resolving A as '212.110.161.144'.
+          #
+          #
+          if ( line =~ /for\s+([^\s]+)\sresolving\s([A-Z]+)\s+as\s'([^']+)'/ )
+            test[:resolve_name]     = $1.dup
+            test[:resolve_type]     = $2.dup
+            test[:resolve_expected] = $3.dup
+          end
+        end
+
+
+        #
+        # We've now parsed the line.  Either output the JSON to the console
+        # or add to the queue.
+        #
+        if ( !ENV['DUMP'].nil? )
+          puts ( test.to_json )
+        else
+          @queue.put( test.to_json )
+        end
+
+        ret.push( test.to_json )
+      end
+
+      ret
+    else
+      puts "Unknown line: '#{line}'"
+    end
+  end
+
+
+
+
+  #
+  # Parse the configuration file which was named in our constructor.
+  #
+  def parse_file()
+    #
+    #  Parse the configuration file on the command line
+    #
+    File.open( @file, "r").each_line do |line|
+      parse_line( line)
+    end
+  end
+
+
+end
+