class TestThreads(OpenTracingTestCase):
def setUp(self):
self.tracer = MockTracer()
self.executor = ThreadPoolExecutor(max_workers=3)
def test_main(self):
res = self.executor.submit(self.parent_task, 'message').result()
self.assertEqual(res, 'message::response')
spans = self.tracer.finished_spans()
self.assertEqual(len(spans), 2)
self.assertNamesEqual(spans, ['child', 'parent'])
self.assertIsChildOf(spans[0], spans[1])
def parent_task(self, message):
with self.tracer.start_active_span('parent', True) as scope:
f = self.executor.submit(self.child_task, message, scope.span)
res = f.result()
return res
def child_task(self, message, span):
with self.tracer.scope_manager.activate(span, False):
with self.tracer.start_active_span('child', True):
return '%s::response' % message
class TestTornado(OpenTracingTestCase):
def setUp(self):
self.tracer = MockTracer(TornadoScopeManager())
self.loop = ioloop.IOLoop.current()
def test_main(self):
parent_task = functools.partial(self.parent_task, 'message')
with TracerStackContext():
res = self.loop.run_sync(parent_task)
self.assertEqual(res, 'message::response')
spans = self.tracer.finished_spans()
self.assertEqual(len(spans), 2)
self.assertNamesEqual(spans, ['child', 'parent'])
self.assertIsChildOf(spans[0], spans[1])
@gen.coroutine
def parent_task(self, message):
with self.tracer.start_active_span('parent', True):
res = yield self.child_task(message)
raise gen.Return(res)
@gen.coroutine
def child_task(self, message):
# No need to pass/activate the parent Span, as
# it stays in the context.
with self.tracer.start_active_span('child', True):
raise gen.Return('%s::response' % message)
class TestGevent(OpenTracingTestCase):
def setUp(self):
self.tracer = MockTracer(GeventScopeManager())
def test_main(self):
# Create a Span and use it as (explicit) parent of a pair of subtasks.
parent_span = self.tracer.start_span('parent')
self.submit_subtasks(parent_span)
gevent.wait(timeout=5.0)
# Late-finish the parent Span now.
parent_span.finish()
spans = self.tracer.finished_spans()
self.assertEqual(len(spans), 3)
self.assertNamesEqual(spans, ['task1', 'task2', 'parent'])
for i in range(2):
self.assertSameTrace(spans[i], spans[-1])
self.assertIsChildOf(spans[i], spans[-1])
self.assertTrue(spans[i].finish_time <= spans[-1].finish_time)
# Fire away a few subtasks, passing a parent Span whose lifetime
# is not tied at all to the children.
def submit_subtasks(self, parent_span):
def task(name):
with self.tracer.start_active_span(name,
True,
child_of=parent_span):
gevent.sleep(0.1)
gevent.spawn(task, 'task1')
gevent.spawn(task, 'task2')
class TestTornado(OpenTracingTestCase):
def setUp(self):
self.tracer = MockTracer(TornadoScopeManager())
self.loop = ioloop.IOLoop.current()
def test_main(self):
# Start an isolated task and query for its result -and finish it-
# in another task/thread
span = self.tracer.start_span('initial')
with TracerStackContext():
self.submit_another_task(span)
stop_loop_when(self.loop,
lambda: len(self.tracer.finished_spans()) >= 3)
self.loop.start()
spans = self.tracer.finished_spans()
self.assertEqual(len(spans), 3)
self.assertNamesEqual(spans, ['initial', 'subtask', 'task'])
# task/subtask are part of the same trace,
# and subtask is a child of task
self.assertSameTrace(spans[1], spans[2])
self.assertIsChildOf(spans[1], spans[2])
# initial task is not related in any way to those two tasks
self.assertNotSameTrace(spans[0], spans[1])
self.assertEqual(spans[0].parent_id, None)
@gen.coroutine
def task(self, span):
# Create a new Span for this task
with self.tracer.start_active_span('task', True):
with self.tracer.scope_manager.activate(span, True):
# Simulate work strictly related to the initial Span
pass
# Use the task span as parent of a new subtask
with self.tracer.start_active_span('subtask', True):
pass
def submit_another_task(self, span):
self.loop.add_callback(self.task, span)
class TestThreads(OpenTracingTestCase):
def setUp(self):
self.tracer = MockTracer()
self.executor = ThreadPoolExecutor(max_workers=3)
def test_main(self):
try:
scope = self.tracer.start_active_span('parent', False)
scope.span._ref_count = RefCount(1)
self.submit_callbacks(scope.span)
finally:
scope.close()
if scope.span._ref_count.decr() == 0:
scope.span.finish()
self.executor.shutdown(True)
spans = self.tracer.finished_spans()
self.assertEquals(len(spans), 4)
self.assertNamesEqual(spans, ['task', 'task', 'task', 'parent'])
for i in range(3):
self.assertSameTrace(spans[i], spans[-1])
self.assertIsChildOf(spans[i], spans[-1])
def task(self, interval, parent_span):
logger.info('Starting task')
try:
scope = self.tracer.scope_manager.activate(parent_span, False)
with self.tracer.start_active_span('task', True):
time.sleep(interval)
finally:
scope.close()
if parent_span._ref_count.decr() == 0:
parent_span.finish()
def submit_callbacks(self, parent_span):
for i in range(3):
parent_span._ref_count.incr()
self.executor.submit(self.task,
0.1 + random.randint(200, 500) * .001,
parent_span)
class TestAsyncio(OpenTracingTestCase):
def setUp(self):
self.tracer = MockTracer(AsyncioScopeManager())
self.loop = asyncio.get_event_loop()
def test_main(self):
# Need to run within a Task, as the scope manager depends
# on Task.current_task()
async def main_task():
with self.tracer.start_active_span('parent', True):
tasks = self.submit_callbacks()
await asyncio.gather(*tasks)
self.loop.create_task(main_task())
stop_loop_when(self.loop, lambda: len(self.tracer.finished_spans()) >= 4)
self.loop.run_forever()
spans = self.tracer.finished_spans()
self.assertEquals(len(spans), 4)
self.assertNamesEqual(spans, ['task', 'task', 'task', 'parent'])
for i in range(3):
self.assertSameTrace(spans[i], spans[-1])
self.assertIsChildOf(spans[i], spans[-1])
async def task(self, interval, parent_span):
logger.info('Starting task')
with self.tracer.scope_manager.activate(parent_span, False):
with self.tracer.start_active_span('task', True):
await asyncio.sleep(interval)
def submit_callbacks(self):
parent_span = self.tracer.scope_manager.active.span
tasks = []
for i in range(3):
interval = 0.1 + random.randint(200, 500) * 0.001
t = self.loop.create_task(self.task(interval, parent_span))
tasks.append(t)
return tasks
class TestThreads(OpenTracingTestCase):
def setUp(self):
self.tracer = MockTracer()
self.executor = ThreadPoolExecutor(max_workers=3)
def test_main(self):
# Start an isolated task and query for its result -and finish it-
# in another task/thread
span = self.tracer.start_span('initial')
self.submit_another_task(span)
self.executor.shutdown(True)
spans = self.tracer.finished_spans()
self.assertEqual(len(spans), 3)
self.assertNamesEqual(spans, ['initial', 'subtask', 'task'])
# task/subtask are part of the same trace,
# and subtask is a child of task
self.assertSameTrace(spans[1], spans[2])
self.assertIsChildOf(spans[1], spans[2])
# initial task is not related in any way to those two tasks
self.assertNotSameTrace(spans[0], spans[1])
self.assertEqual(spans[0].parent_id, None)
def task(self, span):
# Create a new Span for this task
with self.tracer.start_active_span('task', True):
with self.tracer.scope_manager.activate(span, True):
# Simulate work strictly related to the initial Span
pass
# Use the task span as parent of a new subtask
with self.tracer.start_active_span('subtask', True):
pass
def submit_another_task(self, span):
self.executor.submit(self.task, span)
class TestTornado(OpenTracingTestCase):
def setUp(self):
self.tracer = MockTracer(TornadoScopeManager())
self.loop = ioloop.IOLoop.current()
def test_main(self):
# Start a Span and let the callback-chain
# finish it when the task is done
with TracerStackContext():
with self.tracer.start_active_span('one', False):
self.submit()
stop_loop_when(self.loop,
lambda: len(self.tracer.finished_spans()) == 1)
self.loop.start()
spans = self.tracer.finished_spans()
self.assertEqual(len(spans), 1)
self.assertEqual(spans[0].operation_name, 'one')
for i in range(1, 4):
self.assertEqual(spans[0].tags.get('key%s' % i, None), str(i))
# Since TracerStackContext propagates the active Span
# from the first callback, we don't need to re-activate
# it later on anymore.
@gen.coroutine
def submit(self):
span = self.tracer.scope_manager.active.span
@gen.coroutine
def task1():
self.assertEqual(span, self.tracer.scope_manager.active.span)
span.set_tag('key1', '1')
@gen.coroutine
def task2():
self.assertEqual(span, self.tracer.scope_manager.active.span)
span.set_tag('key2', '2')
@gen.coroutine
def task3():
self.assertEqual(span,
self.tracer.scope_manager.active.span)
span.set_tag('key3', '3')
span.finish()
yield task3()
yield task2()
yield task1()
class TestGevent(OpenTracingTestCase):
def setUp(self):
self.tracer = MockTracer(GeventScopeManager())
def test_main(self):
res = gevent.spawn(self.parent_task, 'message').get()
self.assertEqual(res, 'message::response')
spans = self.tracer.finished_spans()
self.assertEqual(len(spans), 2)
self.assertNamesEqual(spans, ['child', 'parent'])
self.assertIsChildOf(spans[0], spans[1])
def parent_task(self, message):
with self.tracer.start_active_span('parent', True) as scope:
res = gevent.spawn(self.child_task, message, scope.span).get()
return res
def child_task(self, message, span):
with self.tracer.scope_manager.activate(span, False):
with self.tracer.start_active_span('child', True):
return '%s::response' % message
class TestGevent(OpenTracingTestCase):
def setUp(self):
self.tracer = MockTracer(GeventScopeManager())
def test_main(self):
def main_task():
with self.tracer.start_active_span('parent', True):
tasks = self.submit_callbacks()
gevent.joinall(tasks)
gevent.spawn(main_task)
gevent.wait(timeout=5.0)
spans = self.tracer.finished_spans()
self.assertEquals(len(spans), 4)
self.assertNamesEqual(spans, ['task', 'task', 'task', 'parent'])
for i in range(3):
self.assertSameTrace(spans[i], spans[-1])
self.assertIsChildOf(spans[i], spans[-1])
def task(self, interval, parent_span):
logger.info('Starting task')
with self.tracer.scope_manager.activate(parent_span, False):
with self.tracer.start_active_span('task', True):
gevent.sleep(interval)
def submit_callbacks(self):
parent_span = self.tracer.scope_manager.active.span
tasks = []
for i in range(3):
interval = 0.1 + random.randint(200, 500) * 0.001
t = gevent.spawn(self.task, interval, parent_span)
tasks.append(t)
return tasks
class TestAsyncio(OpenTracingTestCase):
def setUp(self):
self.tracer = MockTracer(AsyncioScopeManager())
self.loop = asyncio.get_event_loop()
def test_main(self):
res = self.loop.run_until_complete(self.parent_task('message'))
self.assertEqual(res, 'message::response')
spans = self.tracer.finished_spans()
self.assertEqual(len(spans), 2)
self.assertNamesEqual(spans, ['child', 'parent'])
self.assertIsChildOf(spans[0], spans[1])
async def parent_task(self, message):
with self.tracer.start_active_span('parent', True) as scope:
res = await self.child_task(message, scope.span)
return res
async def child_task(self, message, span):
with self.tracer.scope_manager.activate(span, False):
with self.tracer.start_active_span('child', True):
return '%s::response' % message
class TestTornado(OpenTracingTestCase):
def setUp(self):
self.tracer = MockTracer(TornadoScopeManager())
self.loop = ioloop.IOLoop.current()
def test_main(self):
@gen.coroutine
def main_task():
with self.tracer.start_active_span('parent', True):
tasks = self.submit_callbacks()
yield tasks
with TracerStackContext():
self.loop.add_callback(main_task)
stop_loop_when(self.loop,
lambda: len(self.tracer.finished_spans()) == 4)
self.loop.start()
spans = self.tracer.finished_spans()
self.assertEquals(len(spans), 4)
self.assertNamesEqual(spans, ['task', 'task', 'task', 'parent'])
for i in range(3):
self.assertSameTrace(spans[i], spans[-1])
self.assertIsChildOf(spans[i], spans[-1])
@gen.coroutine
def task(self, interval, parent_span):
logger.info('Starting task')
# NOTE: No need to reactivate the parent_span, as TracerStackContext
# keeps track of it, BUT a limitation is that, yielding
# upon multiple coroutines, we cannot mess with the context,
# so no active span set here.
with self.tracer.start_span('task'):
yield gen.sleep(interval)
def submit_callbacks(self):
parent_span = self.tracer.scope_manager.active.span
tasks = []
for i in range(3):
interval = 0.1 + random.randint(200, 500) * 0.001
t = self.task(interval, parent_span)
tasks.append(t)
return tasks
class TestAsyncio(OpenTracingTestCase):
def setUp(self):
self.tracer = MockTracer(AsyncioScopeManager())
self.loop = asyncio.get_event_loop()
def test_main(self):
# Start a Span and let the callback-chain
# finish it when the task is done
async def task():
with self.tracer.start_active_span('one', False):
self.submit()
self.loop.create_task(task())
stop_loop_when(self.loop, lambda: len(self.tracer.finished_spans()) == 1)
self.loop.run_forever()
spans = self.tracer.finished_spans()
self.assertEqual(len(spans), 1)
self.assertEqual(spans[0].operation_name, 'one')
for i in range(1, 4):
self.assertEqual(spans[0].tags.get('key%s' % i, None), str(i))
def submit(self):
span = self.tracer.scope_manager.active.span
async def task1():
with self.tracer.scope_manager.activate(span, False):
span.set_tag('key1', '1')
async def task2():
with self.tracer.scope_manager.activate(span, False):
span.set_tag('key2', '2')
async def task3():
with self.tracer.scope_manager.activate(span,
False):
span.set_tag('key3', '3')
span.finish()
self.loop.create_task(task3())
self.loop.create_task(task2())
self.loop.create_task(task1())
class TestThreads(OpenTracingTestCase):
def setUp(self):
self.tracer = MockTracer()
self.executor = ThreadPoolExecutor(max_workers=3)
def test_main(self):
# Start a Span and let the callback-chain
# finish it when the task is done
with self.tracer.start_active_span('one', False):
self.submit()
# Cannot shutdown the executor and wait for the callbacks
# to be run, as in such case only the first will be executed,
# and the rest will get canceled.
await_until(lambda: len(self.tracer.finished_spans()) == 1, 5)
spans = self.tracer.finished_spans()
self.assertEqual(len(spans), 1)
self.assertEqual(spans[0].operation_name, 'one')
for i in range(1, 4):
self.assertEqual(spans[0].tags.get('key%s' % i, None), str(i))
def submit(self):
span = self.tracer.scope_manager.active.span
def task1():
with self.tracer.scope_manager.activate(span, False):
span.set_tag('key1', '1')
def task2():
with self.tracer.scope_manager.activate(span, False):
span.set_tag('key2', '2')
def task3():
with self.tracer.scope_manager.activate(span, True):
span.set_tag('key3', '3')
self.executor.submit(task3)
self.executor.submit(task2)
self.executor.submit(task1)
class TestGevent(OpenTracingTestCase):
def setUp(self):
self.tracer = MockTracer(GeventScopeManager())
def test_main(self):
# Start a Span and let the callback-chain
# finish it when the task is done
with self.tracer.start_active_span('one', False):
self.submit()
gevent.wait()
spans = self.tracer.finished_spans()
self.assertEqual(len(spans), 1)
self.assertEqual(spans[0].operation_name, 'one')
for i in range(1, 4):
self.assertEqual(spans[0].tags.get('key%s' % i, None), str(i))
def submit(self):
span = self.tracer.scope_manager.active.span
def task1():
with self.tracer.scope_manager.activate(span, False):
span.set_tag('key1', '1')
def task2():
with self.tracer.scope_manager.activate(span, False):
span.set_tag('key2', '2')
def task3():
with self.tracer.scope_manager.activate(
span, True):
span.set_tag('key3', '3')
gevent.spawn(task3)
gevent.spawn(task2)
gevent.spawn(task1)
class TestTornado(OpenTracingTestCase):
def setUp(self):
self.tracer = MockTracer(TornadoScopeManager())
self.loop = ioloop.IOLoop.current()
def test_main(self):
# Create a Span and use it as (explicit) parent of a pair of subtasks.
with TracerStackContext():
parent_span = self.tracer.start_span('parent')
self.submit_subtasks(parent_span)
stop_loop_when(self.loop, lambda: len(self.tracer.finished_spans()) >= 2)
self.loop.start()
# Late-finish the parent Span now.
parent_span.finish()
spans = self.tracer.finished_spans()
self.assertEqual(len(spans), 3)
self.assertNamesEqual(spans, ['task1', 'task2', 'parent'])
for i in range(2):
self.assertSameTrace(spans[i], spans[-1])
self.assertIsChildOf(spans[i], spans[-1])
self.assertTrue(spans[i].finish_time <= spans[-1].finish_time)
# Fire away a few subtasks, passing a parent Span whose lifetime
# is not tied at all to the children.
def submit_subtasks(self, parent_span):
@gen.coroutine
def task(name):
logger.info('Running %s' % name)
with self.tracer.start_active_span(name,
True,
child_of=parent_span):
gen.sleep(0.1)
self.loop.add_callback(task, 'task1')
self.loop.add_callback(task, 'task2')
class TestAsyncio(OpenTracingTestCase):
def setUp(self):
self.tracer = MockTracer(AsyncioScopeManager())
self.loop = asyncio.get_event_loop()
def test_main(self):
# Create a Span and use it as (explicit) parent of a pair of subtasks.
parent_span = self.tracer.start_span('parent')
self.submit_subtasks(parent_span)
stop_loop_when(self.loop,
lambda: len(self.tracer.finished_spans()) >= 2)
self.loop.run_forever()
# Late-finish the parent Span now.
parent_span.finish()
spans = self.tracer.finished_spans()
self.assertEqual(len(spans), 3)
self.assertNamesEqual(spans, ['task1', 'task2', 'parent'])
for i in range(2):
self.assertSameTrace(spans[i], spans[-1])
self.assertIsChildOf(spans[i], spans[-1])
self.assertTrue(spans[i].finish_time <= spans[-1].finish_time)
# Fire away a few subtasks, passing a parent Span whose lifetime
# is not tied at all to the children.
def submit_subtasks(self, parent_span):
async def task(name):
logger.info('Running %s' % name)
with self.tracer.start_active_span(name,
True,
child_of=parent_span):
asyncio.sleep(0.1)
self.loop.create_task(task('task1'))
self.loop.create_task(task('task2'))
class TestThreads(OpenTracingTestCase):
def setUp(self):
self.tracer = MockTracer()
self.executor = ThreadPoolExecutor(max_workers=3)
def test_main(self):
# Create a Span and use it as (explicit) parent of a pair of subtasks.
parent_span = self.tracer.start_span('parent')
self.submit_subtasks(parent_span)
# Wait for the threadpool to be done.
self.executor.shutdown(True)
# Late-finish the parent Span now.
parent_span.finish()
spans = self.tracer.finished_spans()
self.assertEqual(len(spans), 3)
self.assertNamesEqual(spans, ['task1', 'task2', 'parent'])
for i in range(2):
self.assertSameTrace(spans[i], spans[-1])
self.assertIsChildOf(spans[i], spans[-1])
self.assertTrue(spans[i].finish_time <= spans[-1].finish_time)
# Fire away a few subtasks, passing a parent Span whose lifetime
# is not tied at all to the children.
def submit_subtasks(self, parent_span):
def task(name):
with self.tracer.start_active_span(name,
True,
child_of=parent_span):
time.sleep(0.1)
self.executor.submit(task, 'task1')
self.executor.submit(task, 'task2')
class TestGevent(OpenTracingTestCase):
'''
There is only one instance of 'RequestHandler' per 'Client'. Methods of
'RequestHandler' are executed concurrently in different threads which are
reused (common pool). Therefore we cannot use current active span and
activate span. So one issue here is setting correct parent span.
'''
def setUp(self):
self.tracer = MockTracer(GeventScopeManager())
self.client = Client(RequestHandler(self.tracer))
def test_two_callbacks(self):
response_greenlet1 = gevent.spawn(self.client.send_task, 'message1')
response_greenlet2 = gevent.spawn(self.client.send_task, 'message2')
gevent.joinall([response_greenlet1, response_greenlet2])
self.assertEquals('message1::response', response_greenlet1.get())
self.assertEquals('message2::response', response_greenlet2.get())
spans = self.tracer.finished_spans()
self.assertEquals(len(spans), 2)
for span in spans:
self.assertEquals(span.tags.get(tags.SPAN_KIND, None),
tags.SPAN_KIND_RPC_CLIENT)
self.assertNotSameTrace(spans[0], spans[1])
self.assertIsNone(spans[0].parent_id)
self.assertIsNone(spans[1].parent_id)
def test_parent_not_picked(self):
'''Active parent should not be picked up by child.'''
with self.tracer.start_active_span('parent', True):
response = self.client.send_sync('no_parent')
self.assertEquals('no_parent::response', response)
spans = self.tracer.finished_spans()
self.assertEquals(len(spans), 2)
child_span = get_one_by_operation_name(spans, 'send')
self.assertIsNotNone(child_span)
parent_span = get_one_by_operation_name(spans, 'parent')
self.assertIsNotNone(parent_span)
# Here check that there is no parent-child relation.
self.assertIsNotChildOf(child_span, parent_span)
def test_bad_solution_to_set_parent(self):
'''Solution is bad because parent is per client
(we don't have better choice)'''
with self.tracer.start_active_span('parent', True) as scope:
client = Client(RequestHandler(self.tracer, scope.span.context))
response = client.send_sync('correct_parent')
self.assertEquals('correct_parent::response', response)
response = client.send_sync('wrong_parent')
self.assertEquals('wrong_parent::response', response)
spans = self.tracer.finished_spans()
self.assertEquals(len(spans), 3)
spans = sorted(spans, key=lambda x: x.start_time)
parent_span = get_one_by_operation_name(spans, 'parent')
self.assertIsNotNone(parent_span)
self.assertIsChildOf(spans[1], parent_span)
self.assertIsChildOf(spans[2], parent_span)
class TestAsyncio(OpenTracingTestCase):
'''
There is only one instance of 'RequestHandler' per 'Client'. Methods of
'RequestHandler' are executed concurrently in different threads which are
reused (common pool). Therefore we cannot use current active span and
activate span. So one issue here is setting correct parent span.
'''
def setUp(self):
self.tracer = MockTracer(AsyncioScopeManager())
self.loop = asyncio.get_event_loop()
self.client = Client(RequestHandler(self.tracer), self.loop)
def test_two_callbacks(self):
res_future1 = self.loop.create_task(self.client.send('message1'))
res_future2 = self.loop.create_task(self.client.send('message2'))
stop_loop_when(self.loop,
lambda: len(self.tracer.finished_spans()) >= 2)
self.loop.run_forever()
self.assertEquals('message1::response', res_future1.result())
self.assertEquals('message2::response', res_future2.result())
spans = self.tracer.finished_spans()
self.assertEquals(len(spans), 2)
for span in spans:
self.assertEquals(span.tags.get(tags.SPAN_KIND, None),
tags.SPAN_KIND_RPC_CLIENT)
self.assertNotSameTrace(spans[0], spans[1])
self.assertIsNone(spans[0].parent_id)
self.assertIsNone(spans[1].parent_id)
def test_parent_not_picked(self):
'''Active parent should not be picked up by child.'''
async def do():
with self.tracer.start_active_span('parent', True):
response = await self.client.send_task('no_parent')
self.assertEquals('no_parent::response', response)
self.loop.run_until_complete(do())
spans = self.tracer.finished_spans()
self.assertEquals(len(spans), 2)
child_span = get_one_by_operation_name(spans, 'send')
self.assertIsNotNone(child_span)
parent_span = get_one_by_operation_name(spans, 'parent')
self.assertIsNotNone(parent_span)
# Here check that there is no parent-child relation.
self.assertIsNotChildOf(child_span, parent_span)
def test_bad_solution_to_set_parent(self):
'''Solution is bad because parent is per client
(we don't have better choice)'''
async def do():
with self.tracer.start_active_span('parent', True) as scope:
client = Client(
RequestHandler(self.tracer, scope.span.context), self.loop)
response = await client.send_task('correct_parent')
self.assertEquals('correct_parent::response', response)
# Send second request, now there is no active parent, but it will be set, ups
response = await client.send_task('wrong_parent')
self.assertEquals('wrong_parent::response', response)
self.loop.run_until_complete(do())
spans = self.tracer.finished_spans()
self.assertEquals(len(spans), 3)
spans = sorted(spans, key=lambda x: x.start_time)
parent_span = get_one_by_operation_name(spans, 'parent')
self.assertIsNotNone(parent_span)
self.assertIsChildOf(spans[1], parent_span)
self.assertIsChildOf(spans[2], parent_span)