Class: Zipkin::Tracer

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

Constant Summary collapse

DEFAULT_FLUSH_INTERVAL = 
10

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(collector, sender, logger: Logger.new(STDOUT)) ⇒ Tracer

Returns a new instance of Tracer.



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# File 'lib/zipkin/tracer.rb', line 28

def initialize(collector, sender, logger: Logger.new(STDOUT))
  @collector = collector
  @sender = sender
  @logger = logger
end

Class Method Details

.build(url:, service_name:, flush_interval: DEFAULT_FLUSH_INTERVAL, logger: Logger.new(STDOUT)) ⇒ Object 



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# File 'lib/zipkin/tracer.rb', line 16

def self.build(url:, service_name:, flush_interval: DEFAULT_FLUSH_INTERVAL, logger: Logger.new(STDOUT))
  collector = Collector.new(Endpoint.local_endpoint(service_name))
  sender = JsonClient.new(
    url: url,
    collector: collector,
    flush_interval: flush_interval,
    logger: logger
  )
  sender.start
  new(collector, sender, logger: logger)
end

Instance Method Details

#extract(format, carrier) ⇒ SpanContext

Extract a SpanContext in the given format from the given carrier.

Parameters:

  • format (OpenTracing::FORMAT_TEXT_MAP, OpenTracing::FORMAT_BINARY, OpenTracing::FORMAT_RACK)
  • carrier (Carrier) —

    A carrier object of the type dictated by the specified ‘format`

Returns:

  • (SpanContext) —

    the extracted SpanContext or nil if none could be found



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# File 'lib/zipkin/tracer.rb', line 92

def extract(format, carrier)
  case format
  when OpenTracing::FORMAT_TEXT_MAP
    trace_id = carrier['x-b3-traceid']
    parent_id = carrier['x-b3-parentspanid']
    span_id = carrier['x-b3-spanid']
    sampled = carrier['x-b3-sampled'] == '1'

    create_span_context(trace_id, span_id, parent_id, sampled)
  when OpenTracing::FORMAT_RACK
    trace_id = carrier['HTTP_X_B3_TRACEID']
    parent_id = carrier['HTTP_X_B3_PARENTSPANID']
    span_id = carrier['HTTP_X_B3_SPANID']
    sampled = carrier['HTTP_X_B3_SAMPLED'] == '1'

    create_span_context(trace_id, span_id, parent_id, sampled)
  else
    @logger.error "Logasm::Tracer with format #{format} is not supported yet"
    nil
  end
end

#inject(span_context, format, carrier) ⇒ Object

Inject a SpanContext into the given carrier

Parameters:

  • span_context (SpanContext)
  • format (OpenTracing::FORMAT_TEXT_MAP, OpenTracing::FORMAT_BINARY, OpenTracing::FORMAT_RACK)
  • carrier (Carrier) —

    A carrier object of the type dictated by the specified ‘format`



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# File 'lib/zipkin/tracer.rb', line 70

def inject(span_context, format, carrier)
  case format
  when OpenTracing::FORMAT_TEXT_MAP
    carrier['x-b3-traceid'] = span_context.trace_id
    carrier['x-b3-parentspanid'] = span_context.parent_id
    carrier['x-b3-spanid'] = span_context.span_id
    carrier['x-b3-sampled'] = span_context.sampled? ? '1' : '0'
  when OpenTracing::FORMAT_RACK
    carrier['X-B3-TraceId'] = span_context.trace_id
    carrier['X-B3-ParentSpanId'] = span_context.parent_id
    carrier['X-B3-SpanId'] = span_context.span_id
    carrier['X-B3-Sampled'] = span_context.sampled? ? '1' : '0'
  else
    @logger.error "Logasm::Tracer with format #{format} is not supported yet"
  end
end

#start_span(operation_name, child_of: nil, start_time: Time.now, tags: {}) ⇒ Span

Starts a new span.

Parameters:

  • operation_name (String) —

    The operation name for the Span

  • child_of (SpanContext, Span) (defaults to: nil) —

    SpanContext that acts as a parent to the newly-started Span. If a Span instance is provided, its context is automatically substituted.

  • start_time (Time) (defaults to: Time.now) —

    When the Span started, if not now

  • tags (Hash) (defaults to: {}) —

    Tags to assign to the Span at start time

Returns:

  • (Span) —

    The newly-started Span



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# File 'lib/zipkin/tracer.rb', line 48

def start_span(operation_name, child_of: nil, start_time: Time.now, tags: {}, **)
  context =
    if child_of
      parent_context = child_of.respond_to?(:context) ? child_of.context : child_of
      SpanContext.create_from_parent_context(parent_context)
    else
      SpanContext.create_parent_context
    end
  Span.new(
    context,
    operation_name,
    @collector,
    start_time: start_time,
    tags: tags
  )
end

#stop ⇒ Object 



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# File 'lib/zipkin/tracer.rb', line 34

def stop
  @sender.stop
end