Merge pull request #37 from instana/some_refactoring_and_cleanup

Refactor and cleanup

Author: pglombardo

lib/instana/agent.rb

@@ -22,9 +22,6 @@ def initialize
       # Supported two states (unannounced & announced)
       @state = :unannounced
 
-      # Store the pid from process boot so we can detect forks
-      @pid = Process.pid
-
       # Snapshot data is collected once per process but resent
       # every 10 minutes along side process metrics.
       @snapshot = ::Instana::Util.take_snapshot
@@ -57,29 +54,7 @@ def initialize
       # The agent UUID returned from the host agent
       @agent_uuid = nil
 
-      collect_process_info
-    end
-
-    # Used in class initialization and after a fork, this method
-    # collects up process information and stores it in @process
-    #
-    def collect_process_info
-      @process = {}
-      cmdline = ProcTable.ps(Process.pid).cmdline.split("\0")
-      @process[:name] = cmdline.shift
-      @process[:arguments] = cmdline
-
-      if @is_osx
-        # Handle OSX bug where env vars show up at the end of process name
-        # such as MANPATH etc..
-        @process[:name].gsub!(/[_A-Z]+=\S+/, '')
-        @process[:name].rstrip!
-      end
-
-      @process[:original_pid] = @pid
-      # This is usually Process.pid but in the case of docker, the host agent
-      # will return to us the true host pid in which we use to report data.
-      @process[:report_pid] = nil
+      @process = ::Instana::Util.collect_process_info
     end
 
     # Used post fork to re-initialize state and restart communications with
@@ -89,8 +64,7 @@ def after_fork
       ::Instana.logger.agent "after_fork hook called. Falling back to unannounced state and spawning a new background agent thread."
 
       # Re-collect process information post fork
-      @pid = Process.pid
-      collect_process_info
+      @process ::Instana::Util.collect_process_info
 
       transition_to(:unannounced)
       setup
@@ -451,7 +425,7 @@ def get_real_pid
     # @ return [Boolean] true or false to indicate if forked
     #
     def forked?
-      @pid != Process.pid
+      @process[:pid] != Process.pid
     end
   end
 end

lib/instana/base.rb

@@ -20,25 +20,28 @@ class << self
     #
     def setup
       @logger = ::Instana::XLogger.new(STDOUT)
-      if ENV.key?('INSTANA_GEM_TEST') || ENV.key?('INSTANA_GEM_DEV')
-        @logger.level = Logger::DEBUG
-      else
-        @logger.level = Logger::WARN
-      end
       @logger.unknown "Stan is on the scene.  Starting Instana instrumentation."
 
       @agent  = ::Instana::Agent.new
       @tracer = ::Instana::Tracer.new
       @processor = ::Instana::Processor.new
       @collectors = []
+    end
 
-      # Store the current pid so we can detect a potential fork
-      # later on
-      @pid = ::Process.pid
+    # Indicates whether we are running in a development environment.
+    #
+    # @return Boolean
+    #
+    def debug?
+      ENV.key?('INSTANA_GEM_DEV')
     end
 
-    def pid_change?
-      @pid != ::Process.pid
+    # Indicates whether we are running in the test environment.
+    #
+    # @return Boolean
+    #
+    def test?
+      ENV.key?('INSTANA_GEM_TEST')
     end
   end
 end

lib/instana/collectors.rb

@@ -7,7 +7,6 @@ module Instana
   module Collector
     class << self
       attr_accessor :interval
-      attr_accessor :snapshot
 
       ##
       # collect_and_report

lib/instana/collectors/gc.rb

@@ -28,8 +28,8 @@ def collect
         # GC metrics only available on newer Ruby versions
         if RUBY_VERSION >= '2.1'
           # GC runs.  Calculate how many have occurred since the last call
-          @this_gc[:minorGcs]  = stats[:minor_gc_count] - @last_minor_count
-          @this_gc[:majorGcs]  = stats[:major_gc_count] - @last_major_count
+          @this_gc[:minorGcs] = stats[:minor_gc_count] - @last_minor_count
+          @this_gc[:majorGcs] = stats[:major_gc_count] - @last_major_count
 
           # Store these counts so that we have something to compare to next
           # time around.

lib/instana/instrumentation/net-http.rb

@@ -11,21 +11,17 @@ def request_with_instana(*args, &block)
 
     # Send out the tracing context with the request
     request = args[0]
-    our_trace_id = ::Instana.tracer.trace_id
-    our_span_id  = ::Instana.tracer.span_id
 
     # Set request headers; encode IDs as hexadecimal strings
-    request['X-Instana-T'] = ::Instana.tracer.id_to_header(our_trace_id)
-    request['X-Instana-S'] = ::Instana.tracer.id_to_header(our_span_id)
+    request['X-Instana-T'] = ::Instana.tracer.trace_id_header
+    request['X-Instana-S'] = ::Instana.tracer.span_id_header
 
     response = request_without_instana(*args, &block)
 
     # Pickup response headers; convert back to base 10 integer
-    if response.key?('X-Instana-T')
-      their_trace_id = ::Instana.tracer.header_to_id(response.header['X-Instana-T'])
-
-      if our_trace_id != their_trace_id
-        ::Instana.logger.debug "#{Thread.current}: Trace ID mismatch on net/http response! ours: #{our_trace_id} theirs: #{their_trace_id}"
+    if ::Instana.debug? && response.key?('X-Instana-T')
+      if ::Instana.tracer.trace_id != ::Instana.tracer.header_to_id(response.header['X-Instana-T'])
+        ::Instana.logger.debug "#{Thread.current}: Trace ID mismatch on net/http response! ours: #{::Instana.tracer.trace_id} theirs: #{their_trace_id}"
       end
     end
 

lib/instana/logger.rb

@@ -6,8 +6,13 @@ class XLogger < Logger
     STAMP = "Instana: ".freeze
 
     def initialize(*args)
-      if ENV['INSTANA_GEM_DEV']
-        self.debug_level=:agent
+      if ENV.key?('INSTANA_GEM_TEST')
+        self.level = Logger::DEBUG
+      elsif ENV.key?('INSTANA_GEM_DEV')
+        self.level = Logger::DEBUG
+        self.debub_level = nil
+      else
+        self.level = Logger::WARN
       end
       super(*args)
     end
@@ -24,6 +29,8 @@ def initialize(*args)
     # ::Instana.logger.debug_level = [:agent_comm, :trace]
     #
     def debug_level=(levels)
+      return unless levels
+
       LEVELS.each do |l|
         instance_variable_set("@level_#{l}", false)
       end

lib/instana/util.rb

@@ -117,6 +117,29 @@ def take_snapshot
         ::Instana.logger.debug e.backtrace.join("\r\n")
         return data
       end
+
+      # Used in class initialization and after a fork, this method
+      # collects up process information
+      #
+      def collect_process_info
+        process = {}
+        cmdline = ProcTable.ps(Process.pid).cmdline.split("\0")
+        process[:name] = cmdline.shift
+        process[:arguments] = cmdline
+
+        if @is_osx
+          # Handle OSX bug where env vars show up at the end of process name
+          # such as MANPATH etc..
+          process[:name].gsub!(/[_A-Z]+=\S+/, '')
+          process[:name].rstrip!
+        end
+
+        process[:pid] = Process.pid
+        # This is usually Process.pid but in the case of docker, the host agent
+        # will return to us the true host pid in which we use to report data.
+        process[:report_pid] = nil
+        process
+      end
     end
   end
 end