sender.rb in rubix-0.3.0

- old
+ new
@@ -1,433 +1,132 @@
 require 'rubix/log'
+require 'open3'
 
 module Rubix
 
   # A class used to send data to Zabbix.
   #
-  # This sender is used to implement the logic for the +zabbix_pipe+
-  # utility.  It is initialized with some metadata about a host, its
-  # host groups and templates, and applications into which items
-  # should be written, and it can then accept data and forward it to a
-  # Zabbix server using the +zabbix_sender+ utility that comes with
-  # Zabbix.
-  #
-  # A sender can be given data in either TSV or JSON formats.  With
-  # the JSON format, it is possible to embed data for hosts, host
-  # groups, &c. distinct from that with which this sender was
-  # initialized.  This is a useful way to send many different kinds of
-  # data through the same process.
-  #
-  # The sender will also auto-vivify any hosts, host gruops,
-  # templates, applications, and items it needs in order to be able to
-  # write data.  This is expensive in terms of time so it can be
-  # turned off using the <tt>--fast</tt> option.
+  # This sender is used to wrap +zabbix_sender+.
   class Sender
 
     include Logs
 
-    # @return [Hash] settings
-    attr_accessor :settings
-
-    # @return [Rubix::Host] the host the Sender will send data for
-    attr_accessor :host
-
-    # @return [Array<Rubix::HostGroup>] the hostgroups used to create this host
-    attr_accessor :host_groups
-
-    # @return [Array<Rubix::Template>] the templates used to create this host
-    attr_accessor :templates
-
-    # @return [Array<Rubix::Application>] The applications used to create items
-    attr_accessor :applications
-    
     #
-    # == Initialization ==
+    # == Properties ==
     #
 
-    # Create a new sender with the given +settings+.
-    #
-    # @param [Hash, Configliere::Param] settings
-    # @param settings [String] host the name of the Zabbix host to write data for
-    # @param settings [String] host_groups comma-separated names of Zabbix host groups the host should belong to
-    # @param settings [String] templates comma-separated names of Zabbix templates the host should belong to
-    # @param settings [String] applications comma-separated names of applications created items should be scoped under
-    # @param settings [String] server URL for the Zabbix server -- *not* the URL for the Zabbix API
-    # @param settings [String] configuration_file path to a local Zabbix configuration file as used by the +zabbix_sender+ utility
-    # @param settings [true, false] verbose be verbose during execution
-    # @param settings [true, false] fast auto-vivify (slow) or not (fast)
-    # @param settings [String] pipe path to a named pipe to be read from
-    # @param settings [Fixnum] pipe_read_sleep seconds to sleep after an empty read from the a named pipe
-    # @param settings [Fixnum] create_item_sleep seconds to sleep after creating a new item
-    def initialize settings
-      @settings = settings
-      confirm_settings
-      if fast?
-        info("Forwarding for #{settings['host']}...") if settings['verbose']
-      else
-        initialize_host_groups
-        initialize_templates
-        initialize_host
-        initialize_applications
-        info("Forwarding for #{host.name}...") if settings['verbose']
-      end
+    # @return [String] The IP of the Zabbix server
+    attr_writer :server
+    def server
+      @server ||= 'localhost'
     end
 
-    # Is this sender running in 'fast' mode?  If so, it will *not*
-    # auto-vivify any hosts, groups, items, &c.
-    #
-    # @return [true, false]
-    def fast?
-      settings['fast']
+    # @return [String, Rubix::Hosts] the Zabbix host name or Rubix::Host the sender will use by default
+    attr_reader :host
+    def host= nh
+      @host = (nh.respond_to?(:name) ? nh.name : nh.to_s)
     end
 
-    # Will this sender auto-vivify hosts, groups, items, &c.?
-    # 
-    # @return [true, false]
-    def auto_vivify?
-      !fast?
+    # @return [Fixnum] the port to connect to on the Zabbix server
+    attr_writer :port
+    def port
+      @port ||= 10051
     end
 
-    protected
-
-    # Find or create necessary host groups.
-    #
-    # @return [Array<Rubix::HostGroup>]
-    def initialize_host_groups
-      self.host_groups = settings['host_groups'].split(',').flatten.compact.map(&:strip).uniq.map { |group_name | HostGroup.find_or_create(:name => group_name.strip) }
+    # @return [String] the path to the local Zabbix agent configuration file.
+    attr_writer :config
+    def config
+      @config ||= '/etc/zabbix/zabbix_agentd.conf'
     end
 
-    # Find necessary templates.
-    #
-    # @return [Array<Rubix::Template>]
-    def initialize_templates
-      self.templates = (settings['templates'] || '').split(',').flatten.compact.map(&:strip).uniq.map { |template_name | Template.find(:name => template_name.strip) }.compact
+    # Whether or not to include timestamps with the data.
+    attr_writer :timestamps
+    def timestamps?
+      @timestamps
     end
 
-    # Find or create the host for this data.  Host groups and
-    # templates will automatically be attached.
     #
-    # @return [Rubix::Host]
-    def initialize_host
-      self.host = (Host.find(:name => settings['host']) || Host.new(:name => settings['host']))
+    # == Initialization ==
+    #
 
-      current_host_group_names = (host.host_groups || []).map(&:name)
-      current_template_names   = (host.templates || []).map(&:name)
-
-      host_groups_to_add, templates_to_add = [], []
-
-      (self.host_groups || []).each do |hg|
-        host_groups_to_add << hg unless current_host_group_names.include?(hg.name)
-      end
-
-      (self.templates || []).each do |t|
-        templates_to_add << t unless current_template_names.include?(t.name)
-      end
-
-      host.host_groups = ((host.host_groups || []) + host_groups_to_add).flatten.compact.uniq
-      host.templates   = ((host.templates || []) + templates_to_add).flatten.compact.uniq
-      host.save
-      host
-    end
-
-    # Find or create the applications for this data.
+    # Create a new sender with the given +settings+.
     #
-    # @return [Array<Rubix::Application>]
-    def initialize_applications
-      application_names = (settings['applications'] || '').split(',').flatten.compact.map(&:strip).uniq
-      self.applications = []
-      application_names.each do |app_name|
-        app = Application.find(:name => app_name, :host_id => host.id)
-        if app
-          self.applications << app
-        else
-          app = Application.new(:name => app_name, :host_id => host.id)
-          if app.save
-            self.applications << app
-          else
-            warn("Could not create application '#{app_name}' for host #{host.name}")
-          end
-        end
-      end
-      self.applications
+    # @param [Hash, Configliere::Param] settings
+    # @param settings [String, Rubix::Host] host the name of the Zabbix host to write data for
+    # @param settings [String] server the IP of the Zabbix server
+    # @param settings [Fixnum] port the port to connect to on the Zabbix server
+    # @param settings [String] config the path to the local configuration file
+    def initialize settings={}
+      @settings = settings
+      self.server     = settings[:server] if settings[:server]
+      self.host       = settings[:host]   if settings[:host]
+      self.port       = settings[:port]   if settings[:port]
+      self.config     = settings[:config] if settings[:config]
+      self.timestamps = settings[:timestamps]
+      confirm_settings
     end
 
     # Check that all settings are correct in order to be able to
     # successfully write data to Zabbix.
     def confirm_settings
-      raise ConnectionError.new("Must specify a Zabbix server to send data to.")     unless settings['server']
-      raise Error.new("Must specify the path to a local configuraiton file")         unless settings['configuration_file'] && File.file?(settings['configuration_file'])
-      raise ConnectionError.new("Must specify the name of a host to send data for.") unless settings['host']
-      raise ValidationError.new("Must define at least one host group.")              if auto_vivify? && (settings['host_groups'].nil? || settings['host_groups'].empty?)
+      raise Error.new("Must specify a path to a local configuraiton file")    unless config
+      raise Error.new("Must specify the IP of a Zabbix server")               unless server
+      raise Error.new("Must specify the port of a Zabbix server")             unless port && port.to_i > 0
+      raise Error.new("Must specify a default Zabbix host to write data for") unless host
     end
-
-    public
     
     #
     # == Sending Data == 
     #
 
-    # Run this sender.
+    # The environment for the Zabbix sender invocation.
     #
-    # Will read from the correct source of data and exit the Ruby
-    # process once the source is consumed.
-    def run
-      case
-      when settings['pipe']
-        process_pipe
-      when settings.rest.size > 0
-        settings.rest.each do |path|
-          process_file(path)
-        end
-      else
-        process_stdin
-      end
-      exit(0)
+    # @return [Hash]
+    def zabbix_sender_env
+      {}
     end
 
-    protected
-    
-    # Process each line of a file.
+    # Construct the command that invokes Zabbix sender.
     #
-    # @param [String] path the path to the file to process
-    def process_file path
-      f = File.new(path)
-      process_file_handle(f)
-      f.close
-    end
-    
-    # Process each line of standard input.
-    def process_stdin
-      process_file_handle($stdin)
-    end
-    
-    # Process each line read from the pipe.
-    #
-    # The pipe will be opened in a non-blocking read mode.  This
-    # sender will wait 'pipe_read_sleep' seconds between successive
-    # empty reads.
-    def process_pipe
-      # We want to open this pipe in non-blocking read mode b/c
-      # otherwise this process becomes hard to kill.
-      f = File.new(settings['pipe'], (File::RDONLY | File::NONBLOCK))
-      while true
-        process_file_handle(f)
-        # In non-blocking mode, an EOFError from f.readline doesn't mean
-        # there's no more data to read, just that there's no more data
-        # right *now*.  If we sleep for a bit there might be more data
-        # coming down the pipe.
-        sleep settings['pipe_read_sleep']
+    # @return [String]
+    def zabbix_sender_command
+      "timeout 3 zabbix_sender --zabbix-server #{server} --host #{host} --port #{port} --config #{config} --real-time --input-file - -vv".tap do |c|
+        c += " --with-timestamps" if timestamps?
       end
-      f.close
     end
-    
-    # Process each line of a given file handle.
+
+    # Run a +zabbix_sender+ subprocess in the block.
     #
-    # @param [File] f the file to process
-    def process_file_handle f
+    # @yield [IO, IO, IO, Thread] Handle the subprocess.
+    def with_sender_subprocess &block
       begin
-        line = f.readline
-      rescue EOFError
-        line = nil
+        Open3.popen3(zabbix_sender_env, zabbix_sender_command, &block)
+      rescue Errno::ENOENT, Errno::EACCES => e
+        warn(e.message)
       end
-      while line
-        process_line(line)
-        begin
-          # FIXME -- this call to File#readline blocks and doesn't let
-          # stuff like SIGINT (generated from Ctrl-C on a keyboard,
-          # say) take affect.
-          line = f.readline
-        rescue EOFError
-          line = nil
-        end
-      end
     end
 
-    public
-    
-    # Process a single line of text.
+    # Convenience method for sending a block of text to
+    # +zabbix_sender+.
     #
-    # @param [String] line
-    def process_line line
-      if looks_like_json?(line)
-        process_line_of_json_in_new_pipe(line)
-      else
-        process_line_of_tsv_in_this_pipe(line)
+    # @param [String] text
+    def puts text
+      with_sender_subprocess do |stdin, stdout, stderr, wait_thr|
+        stdin.write(text)
+        stdin.close
+        output = [stdout.read.chomp, stderr.read.chomp].join("\n").strip
+        debug(output) if output.size > 0
       end
     end
 
-    protected
-
-    # Parse and send a single +line+ of TSV input to the Zabbix server.
-    # The line will be split at tabs and expects either
-    #
-    #   a) two columns: an item key and a value
-    #   b) three columns: an item key, a value, and a timestamp
-    #
-    # Unexpected input will cause an error to be logged.
-    #
-    # @param [String] line a line of TSV data
-    def process_line_of_tsv_in_this_pipe line
-      parts = line.strip.split("\t")
-      case parts.size
-      when 2
-        timestamp  = Time.now
-        key, value = parts
-      when 3
-        key, value = parts[0..1]
-        timestamp  = Time.parse(parts.last)
-      else
-        error("Each line of input must be a tab separated row consisting of 2 columns (key, value) or 3 columns (timestamp, key, value)")
-        return
-      end
-      send_data(key, value, timestamp)
+    # :nodoc:
+    def close
+      return
     end
 
-    # Parse and send a single +line+ of JSON input to the Zabbix server.
-    # The JSON must have a key +data+ in order to be processed.  The
-    # value of 'data' should be an Array of Hashes each with a +key+ and
-    # +value+.
-    #
-    # This ZabbixPipe's settings will be merged with the remainder of
-    # the JSON hash.  This allows sending values for 'host2' to an
-    # instance of ZabbixPipe already set up to receive for 'host1'.
-    #
-    # This is useful for sending data for keys from multiple hosts
-    #
-    # Example of expected input:
-    #
-    #   {
-    #     'data': [
-    #       {'key': 'foo.bar.baz',      'value': 10},
-    #       {'key': 'snap.crackle.pop', 'value': 8 }
-    #     ]
-    #   }
-    #
-    # Or when sending for another host:
-    # 
-    #   {
-    #     'host': 'shazaam',
-    #     'applications': 'silly',
-    #     'data': [
-    #       {'key': 'foo.bar.baz',      'value': 10},
-    #       {'key': 'snap.crackle.pop', 'value': 8 }
-    #     ]
-    #   }
-    #
-    # @param [String] line a line of JSON data
-    def process_line_of_json_in_new_pipe line
-      begin
-        json = JSON.parse(line)
-      rescue JSON::ParserError => e
-        error("Malformed JSON")
-        return
-      end
-      
-      data = json.delete('data')
-      unless data && data.is_a?(Array)
-        error("A line of JSON input must a have an Array key 'data'")
-        return
-      end
-
-      if json.empty?
-        # If there are no other settings then the daughter will be the
-        # same as the parent -- so just use 'self'.
-        daughter_pipe = self
-      else
-        # We merge the settings from 'self' with whatever else is
-        # present in the line.
-        begin
-          daughter_pipe = self.class.new(settings.stringify_keys.merge(json))
-        rescue Error => e
-          error(e.message)
-          return
-        end
-      end
-
-      data.each do |point|
-        key   = point['key']
-        value = point['value']
-        unless key && value
-          warn("The elements of the 'data' Array must be Hashes with a 'key' and a 'value'")
-          next
-        end
-        
-        tsv_line = [key, value].map(&:to_s).join("\t")
-        daughter_pipe.process_line(tsv_line)
-      end
+    # :nodoc:
+    def flush
+      return
     end
-
-    # Does the +line+ look like it might be JSON?
-    #
-    # @param [String] line
-    # @return [true, false]
-    def looks_like_json? line
-      !!(line =~ /^\s*\{/)
-    end
-
-    # Send the +value+ for +key+ at the given +timestamp+ to the Zabbix
-    # server.
-    #
-    # If the +key+ doesn't exist for this local agent's host, it will be
-    # added.
-    #
-    # FIXME passing +timestamp+ has no effect at present...
-    #
-    # @param [String] key
-    # @param [String, Fixnum, Float] value
-    # @param [Time] timestamp
-    def send_data key, value, timestamp
-      ensure_item_exists(key, value) unless fast?
-      command = "#{settings['sender']} --config #{settings['configuration_file']} --zabbix-server #{settings['server']} --host #{settings['host']} --key #{key} --value '#{value}'"
-      process_zabbix_sender_output(key, `#{command}`)
-
-      # command = "zabbix_sender --config #{configuration_file} --zabbix-server #{server} --input-file - --with-timestamps"
-      # open(command, 'w') do |zabbix_sender|
-      #   zabbix_sender.write([settings['host'], key, timestamp.to_i, value].map(&:to_s).join("\t"))
-      #   zabbix_sender.close_write
-      #   process_zabbix_sender_output(zabbix_sender.read)
-      # end
-    end
-
-    # Create an item for the given +key+ if necessary.
-    #
-    # @param [String] key
-    # @param [String, Fixnum, Float] value
-    def ensure_item_exists key, value
-      item = Item.find(:key => key, :host_id => host.id)
-      unless item
-        Item.new(:key => key, :host_id => host.id, :applications => applications, :value_type => Item.value_type_from_value(value)).save
-        
-        # There is a time lag of about 15-30 seconds between (successfully)
-        # creating an item on the Zabbix server and having the Zabbix accept
-        # new data for that item.
-        #
-        # If it is crucial that *every single* data point be written, dial
-        # up this sleep period.  The first data point for a new key will put
-        # the wrapper to sleep for this period of time, in hopes that the
-        # Zabbix server will catch up and be ready to accept new data
-        # points.
-        #
-        # If you don't care that you're going to lose the first few data
-        # points you send to Zabbix, then don't worry about it.
-        sleep settings['create_item_sleep']
-      end
-    end
     
-    # Parse the +text+ output by +zabbix_sender+.
-    #
-    # @param [String] key
-    # @param [String] text the output from +zabbix_sender+
-    # @return [Fixnum] the number of data points processed
-    def process_zabbix_sender_output key, text
-      return unless settings['verbose']
-      lines = text.strip.split("\n")
-      return if lines.size < 1
-      status_line = lines.first
-      status_line =~ /Processed +(\d+) +Failed +(\d+) +Total +(\d+)/
-      processed, failed, total = $1, $2, $3
-      warn("Failed to write #{failed} values to key '#{key}'") if failed.to_i != 0
-      processed
-    end
-
   end
 end