Replace raised exception for a warning

Author: ocelotl

opentelemetry-api/src/opentelemetry/_metrics/__init__.py

@@ -26,7 +26,7 @@
 from logging import getLogger
 from os import environ
 from threading import Lock
-from typing import List, Optional, cast
+from typing import List, Optional, Set, cast
 
 from opentelemetry._metrics.instrument import (
     Counter,
@@ -115,7 +115,7 @@ def __init__(self, name, version=None, schema_url=None):
         self._name = name
         self._version = version
         self._schema_url = schema_url
-        self._instrument_names = set()
+        self._instrument_ids: Set[str] = set()
         self._instrument_names_lock = Lock()
 
     @property
@@ -130,22 +130,27 @@ def version(self):
     def schema_url(self):
         return self._schema_url
 
-    def _check_instrument_name(self, name):
-        if name.strip().lower() in self._instrument_names:
-            raise Exception(f"Instrument name {name} has been used already")
+    def _check_instrument_name(self, name, type_, unit, description):
 
-        with self._instrument_names_lock:
-            self._instrument_names.add(name)
+        instrument_id = "".join(
+            [name.strip().lower(), str(type_), unit, description]
+        )
+
+        if instrument_id in self._instrument_ids:
+            _logger.warning("Instrument name %s has been used already", name)
+        else:
+
+            self._instrument_ids.add(instrument_id)
 
     @abstractmethod
     def create_counter(self, name, unit="", description="") -> Counter:
-        self._check_instrument_name(name)
+        self._check_instrument_name(name, Counter, unit, description)
 
     @abstractmethod
     def create_up_down_counter(
         self, name, unit="", description=""
     ) -> UpDownCounter:
-        self._check_instrument_name(name)
+        self._check_instrument_name(name, UpDownCounter, unit, description)
 
     @abstractmethod
     def create_observable_counter(
@@ -229,23 +234,25 @@ def cpu_time_callback(states_to_include: set[str]) -> Iterable[Iterable[Measurem
                 example, ``By`` for bytes. UCUM units are recommended.
             description: A description for this instrument and what it measures.
         """
-        self._check_instrument_name(name)
+        self._check_instrument_name(name, ObservableCounter, unit, description)
 
     @abstractmethod
     def create_histogram(self, name, unit="", description="") -> Histogram:
-        self._check_instrument_name(name)
+        self._check_instrument_name(name, Histogram, unit, description)
 
     @abstractmethod
     def create_observable_gauge(
         self, name, callback, unit="", description=""
     ) -> ObservableGauge:
-        self._check_instrument_name(name)
+        self._check_instrument_name(name, ObservableGauge, unit, description)
 
     @abstractmethod
     def create_observable_up_down_counter(
         self, name, callback, unit="", description=""
     ) -> ObservableUpDownCounter:
-        self._check_instrument_name(name)
+        self._check_instrument_name(
+            name, ObservableUpDownCounter, unit, description
+        )
 
 
 class _ProxyMeter(Meter):

opentelemetry-api/tests/metrics/test_meter.py

@@ -13,6 +13,7 @@
 # limitations under the License.
 # type: ignore
 
+from logging import WARNING
 from unittest import TestCase
 from unittest.mock import Mock
 
@@ -121,14 +122,21 @@ def create_observable_up_down_counter(
         for instrument_name in [
             "counter",
             "up_down_counter",
-            "observable_counter",
             "histogram",
+        ]:
+            with self.assertLogs(level=WARNING):
+                getattr(test_meter, f"create_{instrument_name}")(
+                    instrument_name
+                )
+
+        for instrument_name in [
+            "observable_counter",
             "observable_gauge",
             "observable_up_down_counter",
         ]:
-            with self.assertRaises(Exception):
+            with self.assertLogs(level=WARNING):
                 getattr(test_meter, f"create_{instrument_name}")(
-                    instrument_name
+                    instrument_name, Mock()
                 )
 
     def test_create_counter(self):

opentelemetry-sdk/src/opentelemetry/sdk/_metrics/__init__.py

@@ -63,7 +63,7 @@ def __init__(
         self._instrumentation_info = instrumentation_info
         self._measurement_consumer = measurement_consumer
 
-    def create_counter(self, name, unit=None, description=None) -> APICounter:
+    def create_counter(self, name, unit="", description="") -> APICounter:
         super().create_counter(name, unit=unit, description=description)
         return Counter(
             name,
@@ -74,7 +74,7 @@ def create_counter(self, name, unit=None, description=None) -> APICounter:
         )
 
     def create_up_down_counter(
-        self, name, unit=None, description=None
+        self, name, unit="", description=""
     ) -> APIUpDownCounter:
         super().create_up_down_counter(
             name, unit=unit, description=description
@@ -88,7 +88,7 @@ def create_up_down_counter(
         )
 
     def create_observable_counter(
-        self, name, callback, unit=None, description=None
+        self, name, callback, unit="", description=""
     ) -> APIObservableCounter:
         super().create_observable_counter(
             name, callback, unit=unit, description=description
@@ -107,9 +107,7 @@ def create_observable_counter(
 
         return instrument
 
-    def create_histogram(
-        self, name, unit=None, description=None
-    ) -> APIHistogram:
+    def create_histogram(self, name, unit="", description="") -> APIHistogram:
         super().create_histogram(name, unit=unit, description=description)
         return Histogram(
             name,
@@ -120,7 +118,7 @@ def create_histogram(
         )
 
     def create_observable_gauge(
-        self, name, callback, unit=None, description=None
+        self, name, callback, unit="", description=""
     ) -> APIObservableGauge:
         super().create_observable_gauge(
             name, callback, unit=unit, description=description
@@ -140,7 +138,7 @@ def create_observable_gauge(
         return instrument
 
     def create_observable_up_down_counter(
-        self, name, callback, unit=None, description=None
+        self, name, callback, unit="", description=""
     ) -> APIObservableUpDownCounter:
         super().create_observable_up_down_counter(
             name, callback, unit=unit, description=description

opentelemetry-sdk/tests/metrics/test_metrics.py

@@ -288,14 +288,21 @@ def test_repeated_instrument_names(self):
         for instrument_name in [
             "counter",
             "up_down_counter",
-            "observable_counter",
             "histogram",
+        ]:
+            with self.assertLogs(level=WARNING):
+                getattr(self.meter, f"create_{instrument_name}")(
+                    instrument_name
+                )
+
+        for instrument_name in [
+            "observable_counter",
             "observable_gauge",
             "observable_up_down_counter",
         ]:
-            with self.assertRaises(Exception):
+            with self.assertLogs(level=WARNING):
                 getattr(self.meter, f"create_{instrument_name}")(
-                    instrument_name
+                    instrument_name, Mock()
                 )
 
     def test_create_counter(self):