SDK: set sampled flag on sampling trace

[mauriciovasquezbernal]

Fixes #400.

[c24t]

LGTM!

[c24t]

...after doing:

diff --git a/opentelemetry-api/src/opentelemetry/trace/__init__.py b/opentelemetry-api/src/opentelemetry/trace/__init__.py
index 28c1bf40..3473361d 100644
--- a/opentelemetry-api/src/opentelemetry/trace/__init__.py
+++ b/opentelemetry-api/src/opentelemetry/trace/__init__.py
@@ -266,7 +266,9 @@ class TraceOptions(int):
         return cls(cls.DEFAULT)

     @classmethod
-    def get_sampled(cls, other: "TraceOptions" = None) -> "TraceOptions":
+    def get_sampled(
+        cls, other: typing.Optional["TraceOptions"] = None
+    ) -> "TraceOptions":
         if other is None:
             return cls(cls.SAMPLED)
         return cls(other | cls.SAMPLED)
(

[codecov-io]

Codecov Report

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The diff coverage is 100%.

@@            Coverage Diff            @@
##             master     #407   +/-   ##
=========================================
  Coverage          ?   85.86%           
=========================================
  Files             ?       41           
  Lines             ?     2080           
  Branches          ?      242           
=========================================
  Hits              ?     1786           
  Misses            ?      223           
  Partials          ?       71

Impacted Files	Coverage Δ
...ntelemetry-api/src/opentelemetry/trace/__init__.py	84.56% <ø> (ø)
...emetry-sdk/src/opentelemetry/sdk/trace/__init__.py	90.8% <100%> (ø)

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[mauriciovasquezbernal]

@c24t done!

[ocelotl]

LGTM 👍

[c24t]

FYI I reworded the commit because "upon sampling decision" could be interpreted as "on making any sampling decision".

[Oberon00]

Technically, we are modifying a context here which is supposed to be immutable. Since we are the unique owner of the context here (we haven't let anyone else see it yet) that's fine, but I wonder if we should make use of __slots__ and @propertys in SpanContext.