Lint the latest version

Author: fcollonval

opentelemetry-sdk/src/opentelemetry/sdk/metrics/_internal/__init__.py

@@ -34,15 +34,15 @@
 from opentelemetry.metrics import UpDownCounter as APIUpDownCounter
 from opentelemetry.metrics import _Gauge as APIGauge
 from opentelemetry.sdk.environment_variables import (
-    OTEL_SDK_DISABLED, 
     OTEL_METRICS_EXEMPLAR_FILTER,
+    OTEL_SDK_DISABLED,
 )
 from opentelemetry.sdk.metrics._internal.exceptions import MetricsTimeoutError
 from opentelemetry.sdk.metrics._internal.exemplar import (
+    AlwaysOffExemplarFilter,
+    AlwaysOnExemplarFilter,
     ExemplarFilter,
     TraceBasedExemplarFilter,
-    AlwaysOnExemplarFilter,
-    AlwaysOffExemplarFilter,
 )
 from opentelemetry.sdk.metrics._internal.instrument import (
     _Counter,
@@ -349,6 +349,17 @@ def create_observable_up_down_counter(
             return instrument
 
 
+def _get_exemplar_filter(exemplar_filter: str) -> ExemplarFilter:
+    if exemplar_filter == "trace_based":
+        return TraceBasedExemplarFilter()
+    if exemplar_filter == "always_on":
+        return AlwaysOnExemplarFilter()
+    if exemplar_filter == "always_off":
+        return AlwaysOffExemplarFilter()
+    msg = f"Unknown exemplar filter '{exemplar_filter}'."
+    raise ValueError(msg)
+
+
 class MeterProvider(APIMeterProvider):
     r"""See `opentelemetry.metrics.MeterProvider`.
 
@@ -399,12 +410,12 @@ def __init__(
         self._atexit_handler = None
         if resource is None:
             resource = Resource.create({})
-        filter = environ.get(OTEL_METRICS_EXEMPLAR_FILTER, None)
         self._sdk_config = SdkConfiguration(
             exemplar_filter=(
                 exemplar_filter
-                if exemplar_filter is not None
-                else self._get_exemplar_filter(filter)
+                or _get_exemplar_filter(
+                    environ.get(OTEL_METRICS_EXEMPLAR_FILTER, "trace_based")
+                )
             ),
             resource=resource,
             metric_readers=metric_readers,
@@ -562,14 +573,3 @@ def get_meter(
                     self._measurement_consumer,
                 )
             return self._meters[info]
-
-    def _get_exemplar_filter(self, exemplar_filter: str) -> ExemplarFilter:
-        if not exemplar_filter or exemplar_filter == 'trace_based':
-            return TraceBasedExemplarFilter()
-        elif exemplar_filter == 'always_on':
-            return AlwaysOnExemplarFilter()
-        elif exemplar_filter == 'always_off':
-            return AlwaysOffExemplarFilter()
-        else: 
-            raise Exception("Invalid exemplar filter.")
-