79 lines
2.2 KiB
Python
79 lines
2.2 KiB
Python
import random
|
|
|
|
from eventlet import wsgi
|
|
from eventlet.zipkin import api
|
|
from eventlet.zipkin._thrift.zipkinCore.constants import \
|
|
SERVER_RECV, SERVER_SEND
|
|
from eventlet.zipkin.http import \
|
|
HDR_TRACE_ID, HDR_SPAN_ID, HDR_PARENT_SPAN_ID, HDR_SAMPLED
|
|
|
|
|
|
_sampler = None
|
|
__original_handle_one_response__ = wsgi.HttpProtocol.handle_one_response
|
|
|
|
|
|
def _patched_handle_one_response(self):
|
|
api.init_trace_data()
|
|
trace_id = int_or_none(self.headers.getheader(HDR_TRACE_ID))
|
|
span_id = int_or_none(self.headers.getheader(HDR_SPAN_ID))
|
|
parent_id = int_or_none(self.headers.getheader(HDR_PARENT_SPAN_ID))
|
|
sampled = bool_or_none(self.headers.getheader(HDR_SAMPLED))
|
|
if trace_id is None: # front-end server
|
|
trace_id = span_id = api.generate_trace_id()
|
|
parent_id = None
|
|
sampled = _sampler.sampling()
|
|
ip, port = self.request.getsockname()[:2]
|
|
ep = api.ZipkinDataBuilder.build_endpoint(ip, port)
|
|
trace_data = api.TraceData(name=self.command,
|
|
trace_id=trace_id,
|
|
span_id=span_id,
|
|
parent_id=parent_id,
|
|
sampled=sampled,
|
|
endpoint=ep)
|
|
api.set_trace_data(trace_data)
|
|
api.put_annotation(SERVER_RECV)
|
|
api.put_key_value('http.uri', self.path)
|
|
|
|
__original_handle_one_response__(self)
|
|
|
|
if api.is_sample():
|
|
api.put_annotation(SERVER_SEND)
|
|
|
|
|
|
class Sampler(object):
|
|
def __init__(self, sampling_rate):
|
|
self.sampling_rate = sampling_rate
|
|
|
|
def sampling(self):
|
|
# avoid generating unneeded random numbers
|
|
if self.sampling_rate == 1.0:
|
|
return True
|
|
r = random.random()
|
|
if r < self.sampling_rate:
|
|
return True
|
|
return False
|
|
|
|
|
|
def int_or_none(val):
|
|
if val is None:
|
|
return None
|
|
return int(val, 16)
|
|
|
|
|
|
def bool_or_none(val):
|
|
if val == '1':
|
|
return True
|
|
if val == '0':
|
|
return False
|
|
return None
|
|
|
|
|
|
def patch(sampling_rate):
|
|
global _sampler
|
|
_sampler = Sampler(sampling_rate)
|
|
wsgi.HttpProtocol.handle_one_response = _patched_handle_one_response
|
|
|
|
|
|
def unpatch():
|
|
wsgi.HttpProtocol.handle_one_response = __original_handle_one_response__
|