Add check for duplicate instrument names

Fixes open-telemetry#2142

Author: ocelotl

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

@@ -129,17 +129,21 @@ def version(self):
     def schema_url(self):
         return self._schema_url
 
-    # FIXME check that the instrument name has not been used already
+    def _check_instrument_name(self, name):
+        if name in self._instrument_names:
+            raise Exception(f"Instrument name {name} has been used already")
+
+        self._instrument_names.add(name)
 
     @abstractmethod
     def create_counter(self, name, unit="", description="") -> Counter:
-        pass
+        self._check_instrument_name(name)
 
     @abstractmethod
     def create_up_down_counter(
         self, name, unit="", description=""
     ) -> UpDownCounter:
-        pass
+        self._check_instrument_name(name)
 
     @abstractmethod
     def create_observable_counter(
@@ -223,22 +227,23 @@ 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)
 
     @abstractmethod
     def create_histogram(self, name, unit="", description="") -> Histogram:
-        pass
+        self._check_instrument_name(name)
 
     @abstractmethod
     def create_observable_gauge(
         self, name, callback, unit="", description=""
     ) -> ObservableGauge:
-        pass
+        self._check_instrument_name(name)
 
     @abstractmethod
     def create_observable_up_down_counter(
         self, name, callback, unit="", description=""
     ) -> ObservableUpDownCounter:
-        pass
+        self._check_instrument_name(name)
 
 
 class _ProxyMeter(Meter):

opentelemetry-api/tests/metrics/test_meter.py

@@ -14,8 +14,17 @@
 # type: ignore
 
 from unittest import TestCase
+from unittest.mock import Mock
 
 from opentelemetry._metrics import Meter
+from opentelemetry._metrics.instrument import (
+    Counter,
+    Histogram,
+    ObservableCounter,
+    ObservableGauge,
+    ObservableUpDownCounter,
+    UpDownCounter,
+)
 
 # FIXME Test that the meter methods can be called concurrently safely.
 
@@ -53,6 +62,75 @@ def create_observable_up_down_counter(
 
 
 class TestMeter(TestCase):
+    def test_repeated_instrument_names(self):
+        class TestMeter(Meter):
+            def create_counter(self, name, unit="", description="") -> Counter:
+                super().create_counter(
+                    name, unit=unit, description=description
+                )
+
+            def create_up_down_counter(
+                self, name, unit="", description=""
+            ) -> UpDownCounter:
+                super().create_up_down_counter(
+                    name, unit=unit, description=description
+                )
+
+            def create_observable_counter(
+                self, name, callback, unit="", description=""
+            ) -> ObservableCounter:
+                super().create_observable_up_down_counter(
+                    name, callback, unit=unit, description=description
+                )
+
+            def create_histogram(
+                self, name, unit="", description=""
+            ) -> Histogram:
+                super().create_histogram(
+                    name, unit=unit, description=description
+                )
+
+            def create_observable_gauge(
+                self, name, callback, unit="", description=""
+            ) -> ObservableGauge:
+                super().create_observable_gauge(
+                    name, callback, unit=unit, description=description
+                )
+
+            def create_observable_up_down_counter(
+                self, name, callback, unit="", description=""
+            ) -> ObservableUpDownCounter:
+                super().create_observable_up_down_counter(
+                    name, callback, unit=unit, description=description
+                )
+
+        try:
+            test_meter = TestMeter("name")
+
+            test_meter.create_counter("counter")
+            test_meter.create_up_down_counter("up_down_counter")
+            test_meter.create_observable_counter("observable_counter", Mock())
+            test_meter.create_histogram("histogram")
+            test_meter.create_observable_gauge("observable_gauge", Mock())
+            test_meter.create_observable_up_down_counter(
+                "observable_up_down_counter", Mock()
+            )
+        except Exception as error:
+            self.fail(f"Unexpected exception raised {error}")
+
+        for instrument_name in [
+            "counter",
+            "up_down_counter",
+            "observable_counter",
+            "histogram",
+            "observable_gauge",
+            "observable_up_down_counter",
+        ]:
+            with self.assertRaises(Exception):
+                getattr(test_meter, f"create_{instrument_name}")(
+                    instrument_name
+                )
+
     def test_create_counter(self):
         """
         Test that the meter provides a function to create a new Counter

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

@@ -64,6 +64,7 @@ def __init__(
         self._measurement_consumer = measurement_consumer
 
     def create_counter(self, name, unit=None, description=None) -> APICounter:
+        super().create_counter(name, unit=unit, description=description)
         return Counter(
             name,
             self._instrumentation_info,
@@ -75,6 +76,9 @@ def create_counter(self, name, unit=None, description=None) -> APICounter:
     def create_up_down_counter(
         self, name, unit=None, description=None
     ) -> APIUpDownCounter:
+        super().create_up_down_counter(
+            name, unit=unit, description=description
+        )
         return UpDownCounter(
             name,
             self._instrumentation_info,
@@ -86,6 +90,9 @@ def create_up_down_counter(
     def create_observable_counter(
         self, name, callback, unit=None, description=None
     ) -> APIObservableCounter:
+        super().create_observable_counter(
+            name, callback, unit=unit, description=description
+        )
 
         instrument = ObservableCounter(
             name,
@@ -103,6 +110,7 @@ def create_observable_counter(
     def create_histogram(
         self, name, unit=None, description=None
     ) -> APIHistogram:
+        super().create_histogram(name, unit=unit, description=description)
         return Histogram(
             name,
             self._instrumentation_info,
@@ -114,6 +122,9 @@ def create_histogram(
     def create_observable_gauge(
         self, name, callback, unit=None, description=None
     ) -> APIObservableGauge:
+        super().create_observable_gauge(
+            name, callback, unit=unit, description=description
+        )
 
         instrument = ObservableGauge(
             name,
@@ -131,6 +142,9 @@ def create_observable_gauge(
     def create_observable_up_down_counter(
         self, name, callback, unit=None, description=None
     ) -> APIObservableUpDownCounter:
+        super().create_observable_up_down_counter(
+            name, callback, unit=unit, description=description
+        )
 
         instrument = ObservableUpDownCounter(
             name,

opentelemetry-sdk/tests/metrics/test_metrics.py

@@ -217,17 +217,17 @@ def test_register_asynchronous_instrument(
 
         meter_provider._measurement_consumer.register_asynchronous_instrument.assert_called_with(
             meter_provider.get_meter("name").create_observable_counter(
-                "name", Mock()
+                "name0", Mock()
             )
         )
         meter_provider._measurement_consumer.register_asynchronous_instrument.assert_called_with(
             meter_provider.get_meter("name").create_observable_up_down_counter(
-                "name", Mock()
+                "name1", Mock()
             )
         )
         meter_provider._measurement_consumer.register_asynchronous_instrument.assert_called_with(
             meter_provider.get_meter("name").create_observable_gauge(
-                "name", Mock()
+                "name2", Mock()
             )
         )