from __future__ import absolute_import
from base64 import standard_b64decode
from base64 import standard_b64encode
from basictracer.context import SpanContext
from basictracer.propagator import Propagator
# This can cause problems when old versions of protobuf are installed
from opentracing import InvalidCarrierException
from lightstep.lightstep_carrier_pb2 import BinaryCarrier
from lightstep.lightstep_carrier_pb2 import BasicTracerCarrier
class LightStepBinaryPropagator(Propagator):
"""A BasicTracer Propagator for LightStepFormat.LIGHTSTEP_BINARY."""
def inject(self, span_context, carrier):
if type(carrier) is not bytearray:
raise InvalidCarrierException()
state = BinaryCarrier()
basic_ctx = state.basic_ctx
basic_ctx.trace_id = span_context.trace_id
basic_ctx.span_id = span_context.span_id
basic_ctx.sampled = span_context.sampled
if span_context.baggage is not None:
for key in span_context.baggage:
basic_ctx.baggage_items[key] = span_context.baggage[key]
serializedProto = state.SerializeToString()
encoded = standard_b64encode(serializedProto)
carrier.extend(encoded)
def extract(self, carrier):
if type(carrier) is not bytearray:
raise InvalidCarrierException()
serializedProto = standard_b64decode(carrier)
state = BinaryCarrier()
state.ParseFromString(bytes(serializedProto))
baggage = {}
for k in state.basic_ctx.baggage_items:
baggage[k] = state.basic_ctx.baggage_items[k]
return SpanContext(
span_id=state.basic_ctx.span_id,
trace_id=state.basic_ctx.trace_id,
baggage=baggage,
sampled=state.basic_ctx.sampled)
