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authorSteve Kemp <steve@steve.org.uk>2012-11-14 16:41:25 +0000
committerSteve Kemp <steve@steve.org.uk>2012-11-14 16:41:25 +0000
commit2115aa33f5a05738aef33060595aac6eee1762a0 (patch)
tree75dee415c06da7e0bac61c5aa9360fea69c39be9 /lib/custodian/parser.rb
parent88ed0643a43bf27093229486d2ad8227f6ec2c18 (diff)
Moved parser code into its own file, and updated main script + test suite to use it.
Diffstat (limited to 'lib/custodian/parser.rb')
-rwxr-xr-xlib/custodian/parser.rb451
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
+