main.py 文件源码

def add_spans():
    """Calls the opentracing API, doesn't use any LightStep-specific code.
    """
    with opentracing.tracer.start_span(operation_name='trivial/initial_request') as parent_span:
        parent_span.set_tag('url', 'localhost')
        parent_span.log_event('All good here!', payload={'N': 42, 'pi': 3.14, 'abc': 'xyz'})
        parent_span.set_tag('span_type', 'parent')
        parent_span.set_baggage_item('checked', 'baggage')

        rng = random.SystemRandom()
        for i in range(50):
            time.sleep(rng.random() * 0.2)
            sys.stdout.write('.')
            sys.stdout.flush()

            # This is how you would represent starting work locally.
            with opentracing.start_child_span(parent_span, operation_name='trivial/child_request') as child_span:
                child_span.log_event('Uh Oh!', payload={'error': True})
                child_span.set_tag('span_type', 'child')

                # Play with the propagation APIs... this is not IPC and thus not
                # where they're intended to be used.
                text_carrier = {}
                opentracing.tracer.inject(child_span.context, opentracing.Format.TEXT_MAP, text_carrier)

                span_context = opentracing.tracer.extract(opentracing.Format.TEXT_MAP, text_carrier)
                with opentracing.tracer.start_span(
                    'nontrivial/remote_span',
                    child_of=span_context) as remote_span:
                        remote_span.log_event('Remote!')
                        remote_span.set_tag('span_type', 'remote')
                        time.sleep(rng.random() * 0.1)

                opentracing.tracer.flush()