Class: RubyZipkin::RackHandler

Inherits:
Object
  • Object
show all
Defined in:
lib/rubyzipkin.rb

Instance Method Summary collapse

Constructor Details

#initialize(app, service_name, scribe_server, scribe_port, uri_filter_list = [], http_header_filter_list = [], uri_sample_filter_list = {}, sampling_rate = 0.0001, scribe_max_buffer = 50, redis_config = 'config/redis.yml') ⇒ RackHandler

Returns a new instance of RackHandler.



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# File 'lib/rubyzipkin.rb', line 17

def initialize(app, service_name, scribe_server, scribe_port, uri_filter_list = [], http_header_filter_list = [], uri_sample_filter_list = {}, sampling_rate = 0.0001, scribe_max_buffer = 50, redis_config = 'config/redis.yml')
  @app = app
  @lock = Mutex.new

  @service_name = service_name
  @scribe_port = scribe_port
  @sample_rate = sampling_rate
  @uri_filter_list = uri_filter_list
  @http_header_filter_list = http_header_filter_list
  @uri_sample_filter_list = uri_sample_filter_list
  @scribe = Scribe.new("#{scribe_server}:#{scribe_port}")
  @redis_config = redis_config
  @sampled_ids = {}
  $redis_check_time = Time.now
  ::Trace.tracer = ::Trace::ZipkinTracer.new(Scriber.new(@scribe), scribe_max_buffer)

  begin
    if $redis.nil?
      $redis = redis_from_config(@redis_config) if File.exist?(@redis_config)
    end
  rescue => e
    $stderr.puts "ZIPKIN [ERR] Redis instance could not be configured (nil)"
  end
end

Instance Method Details

#add_referer(env) ⇒ Object 



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# File 'lib/rubyzipkin.rb', line 154

def add_referer(env)
  if env['HTTP_REFERER']
    ::Trace.record(::Trace::BinaryAnnotation.new("http.referer", env['HTTP_REFERER'], "STRING", ::Trace.default_endpoint))
  end
end

#call(env) ⇒ Object 



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# File 'lib/rubyzipkin.rb', line 42

def call(env)

  if $redis.nil?
    return
  end

  begin
    ::Trace.default_endpoint = ::Trace.default_endpoint.with_service_name(@service_name + "/#{top_level_path(env['PATH_INFO'])}")
    set_sample_rate(env)
    trace_id = get_or_create_trace_id(env)
  rescue => e
    $stderr.puts "ZIPKIN [ERR] #{e}"
  end

  begin
    status, headers, response = @app.call(env)
    redis_sampling(headers)
    tracing_filter(trace_id, env, headers, status)
  rescue => e
    # we want to do the call even if zipkin fails
    $stderr.puts "ZIPKIN [ERR] #{e} \n\n\n #{e.backtrace}"
  end
  [status, headers, response]
end

#get_or_create_trace_id(env) ⇒ Object

Generates a trace ID set in Finagle’s format

  • @param _traceId The id for this request.

  • @param _parentId The id for the request one step up the service stack.

  • @param spanId The id for this particular request

  • @param _sampled Should we sample this request or not? True means sample, false means don’t.



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# File 'lib/rubyzipkin.rb', line 201

def get_or_create_trace_id(env)

  if env[ZipkinTraceHeader::TRACE_ID].nil? or env[ZipkinTraceHeader::TRACE_ID].to_s.empty?
    @tid = Trace.generate_id
    env[ZipkinTraceHeader::TRACE_ID] = @tid
  else
    @tid = env[ZipkinTraceHeader::TRACE_ID]
  end

  if env[ZipkinTraceHeader::SPAN_ID].nil? or env[ZipkinTraceHeader::SPAN_ID].to_s.empty?
      @parentspan = nil
  else
      @parentspan = env[ZipkinTraceHeader::SPAN_ID]
  end

  @spanid = Trace.generate_id

  # Save into HTTP headers
  env[ZipkinTraceHeader::TRACE_ID] = @trace_id
  env[ZipkinTraceHeader::SPAN_ID] = @spanid
  env[ZipkinTraceHeader::PARENT_SPAN_ID] = @parentspan

  Trace::TraceId.new(@tid, @parentspan, @spanid, true)
end

#get_or_create_trace_id2(env) ⇒ Object 



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# File 'lib/rubyzipkin.rb', line 226

def get_or_create_trace_id2(env)
  ::Trace::TraceId.new(::Trace.generate_id, nil, ::Trace.generate_id, true)
end

#normalized_uri(path) ⇒ Object 



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# File 'lib/rubyzipkin.rb', line 160

def normalized_uri(path)
  path.gsub(/\/\d+/, '/:id')
end

#redis_sampled_ids ⇒ Object

Return the current set of IDS to be unsampled as selected from redis.



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# File 'lib/rubyzipkin.rb', line 69

def redis_sampled_ids
  @sampled_ids.to_s
end

#set_trace_caption(env, status) ⇒ Object 



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# File 'lib/rubyzipkin.rb', line 177

def set_trace_caption(env, status)
  ::Trace.set_rpc_name("#{env['REQUEST_METHOD']} - #{status.to_s} - #{uri_summary(env['PATH_INFO'])}")
end

#top_level_path(path) ⇒ Object 



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# File 'lib/rubyzipkin.rb', line 164

def top_level_path(path)
  path.split('/')[1]
end

#trace_hash(content) ⇒ Object 



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# File 'lib/rubyzipkin.rb', line 186

def trace_hash(content)
  if content
    content.sort.map do |k,v|
      unless RubyZipkin::TraceFilter.KeywordFilterMatches?(k.to_s, @http_header_filter_list)
        MetadataLogger.log(k.to_s, v)
      end
    end
  end
end

#trace_post_data(content) ⇒ Object 



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# File 'lib/rubyzipkin.rb', line 181

def trace_post_data(content)
  # Slightly large size cap to the request input to accomodate larger JSON bodies.
  MetadataLogger.log('HTTP_REQUEST_INPUT', content.to_s, 1024)
end

#uri_summary(path) ⇒ Object 



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# File 'lib/rubyzipkin.rb', line 168

def uri_summary(path)
  suffix = path.match /\w+$/
  if suffix.to_s.length > 10
    normalized_uri(path.gsub(/\w+$/,''))
  else
    normalized_uri(path)
  end
end