Revert b3_format.py

Author: ocelotl

opentelemetry-sdk/src/opentelemetry/sdk/context/propagation/b3_format.py

@@ -27,7 +27,6 @@ class B3Format(HTTPTextFormat):
     SINGLE_HEADER_KEY = "b3"
     TRACE_ID_KEY = "x-b3-traceid"
     SPAN_ID_KEY = "x-b3-spanid"
-    PARENT_SPAN_ID_KEY = "x-b3-parentspanid"
     SAMPLED_KEY = "x-b3-sampled"
     FLAGS_KEY = "x-b3-flags"
     _SAMPLE_PROPAGATE_VALUES = set(["1", "True", "true", "d"])
@@ -36,7 +35,6 @@ class B3Format(HTTPTextFormat):
     def extract(cls, get_from_carrier, carrier):
         trace_id = format_trace_id(trace.INVALID_TRACE_ID)
         span_id = format_span_id(trace.INVALID_SPAN_ID)
-        parent_span_id = format_span_id(trace.INVALID_SPAN_ID)
         sampled = "0"
         flags = None
 
@@ -57,7 +55,7 @@ def extract(cls, get_from_carrier, carrier):
             elif len(fields) == 3:
                 trace_id, span_id, sampled = fields
             elif len(fields) == 4:
-                trace_id, span_id, sampled, parent_span_id = fields
+                trace_id, span_id, sampled, _parent_span_id = fields
             else:
                 return trace.INVALID_SPAN_CONTEXT
         else:
@@ -73,12 +71,6 @@ def extract(cls, get_from_carrier, carrier):
                 )
                 or span_id
             )
-            parent_span_id = (
-                _extract_first_element(
-                    get_from_carrier(carrier, cls.PARENT_SPAN_ID_KEY)
-                )
-                or parent_span_id
-            )
             sampled = (
                 _extract_first_element(
                     get_from_carrier(carrier, cls.SAMPLED_KEY)
@@ -99,22 +91,12 @@ def extract(cls, get_from_carrier, carrier):
         # header is set to allow.
         if sampled in cls._SAMPLE_PROPAGATE_VALUES or flags == "1":
             options |= trace.TraceOptions.SAMPLED
-
-        trace_state = trace.TraceState()
-
-        if parent_span_id != trace.INVALID_SPAN_ID:
-            # FIXME This is a workaround for the error specified below being
-            # raised because of a pylint issue. Remove this when the issue is
-            # fixed in pylint.
-            # pylint: disable=E1137
-            trace_state[cls.PARENT_SPAN_ID_KEY] = int(parent_span_id, 16)
-
         return trace.SpanContext(
             # trace an span ids are encoded in hex, so must be converted
             trace_id=int(trace_id, 16),
             span_id=int(span_id, 16),
             trace_options=trace.TraceOptions(options),
-            trace_state=trace_state,
+            trace_state=trace.TraceState(),
         )
 
     @classmethod
@@ -126,11 +108,6 @@ def inject(cls, context, set_in_carrier, carrier):
         set_in_carrier(
             carrier, cls.SPAN_ID_KEY, format_span_id(context.span_id)
         )
-        set_in_carrier(
-            carrier,
-            cls.PARENT_SPAN_ID_KEY,
-            format_span_id(context.trace_state[cls.PARENT_SPAN_ID_KEY]),
-        )
         set_in_carrier(carrier, cls.SAMPLED_KEY, "1" if sampled else "0")