main.py

"""
Synthetic example with high concurrency. Used primarily to stress test the
library.
"""
import argparse
import contextlib
import sys
import time
import threading
import random

# Comment out to test against the published copy
import os
sys.path.insert(1, os.path.dirname(os.path.realpath(__file__)) + '/../..')

import opentracing
import lightstep

def sleep_dot():
    """Short sleep and writes a dot to the STDOUT.
    """
    time.sleep(0.05)
    sys.stdout.write('.')
    sys.stdout.flush()

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()


def lightstep_tracer_from_args():
    """Initializes lightstep from the commandline args.
    """
    parser = argparse.ArgumentParser()
    parser.add_argument('--token', help='Your LightStep access token.',
                        default='{your_access_token}')
    parser.add_argument('--host', help='The LightStep reporting service host to contact.',
                        default='collector.lightstep.com')
    parser.add_argument('--port', help='The LightStep reporting service port.',
                        type=int, default=443)
    parser.add_argument('--use_tls', help='Add this argument if you want to use TLS.',
                        action='store_true')
    parser.add_argument('--component_name', help='The LightStep component name',
                        default='NonTrivialExample')
    args = parser.parse_args()

    return lightstep.Tracer(
	    component_name=args.component_name,
	    access_token=args.token,
	    collector_host=args.host,
	    collector_port=args.port,
        collector_encryption=('tls' if args.use_tls else 'none'))


if __name__ == '__main__':
    print('Hello '),

    # Use LightStep's opentracing implementation
    with lightstep_tracer_from_args() as tracer:
        opentracing.tracer = tracer

        for j in range(20):
            threads = []
            for i in range(64):
                t = threading.Thread(target=add_spans)
                threads.append(t)
                t.start()
            for t in threads:
                t.join()
            print('\n')

    print(' World!')