Instrument instances are always created through a Meter (#2844)

* Instrument instances are always created through a Meter

* Fix lint and add changelog

* fix lint

CHANGELOG.md

@@ -17,6 +17,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   ([#2754](https://github.com/open-telemetry/opentelemetry-python/pull/2754))
 - Fix --insecure of CLI argument
   ([#2696](https://github.com/open-telemetry/opentelemetry-python/pull/2696))
+-  Instrument instances are always created through a Meter
+  ([#2844](https://github.com/open-telemetry/opentelemetry-python/pull/2844))
 
 ## [1.12.0rc2-0.32b0](https://github.com/open-telemetry/opentelemetry-python/releases/tag/v1.12.0rc2) - 2022-07-04
 

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

@@ -31,12 +31,12 @@
 )
 from opentelemetry.metrics import UpDownCounter as APIUpDownCounter
 from opentelemetry.sdk.metrics._internal.instrument import (
-    Counter,
-    Histogram,
-    ObservableCounter,
-    ObservableGauge,
-    ObservableUpDownCounter,
-    UpDownCounter,
+    _Counter,
+    _Histogram,
+    _ObservableCounter,
+    _ObservableGauge,
+    _ObservableUpDownCounter,
+    _UpDownCounter,
 )
 from opentelemetry.sdk.metrics._internal.measurement_consumer import (
     MeasurementConsumer,
@@ -72,7 +72,7 @@ def create_counter(self, name, unit="", description="") -> APICounter:
         (
             is_instrument_registered,
             instrument_id,
-        ) = self._is_instrument_registered(name, Counter, unit, description)
+        ) = self._is_instrument_registered(name, _Counter, unit, description)
 
         if is_instrument_registered:
             # FIXME #2558 go through all views here and check if this
@@ -89,7 +89,7 @@ def create_counter(self, name, unit="", description="") -> APICounter:
             with self._instrument_id_instrument_lock:
                 return self._instrument_id_instrument[instrument_id]
 
-        instrument = Counter(
+        instrument = _Counter(
             name,
             self._instrumentation_scope,
             self._measurement_consumer,
@@ -109,7 +109,7 @@ def create_up_down_counter(
             is_instrument_registered,
             instrument_id,
         ) = self._is_instrument_registered(
-            name, UpDownCounter, unit, description
+            name, _UpDownCounter, unit, description
         )
 
         if is_instrument_registered:
@@ -127,7 +127,7 @@ def create_up_down_counter(
             with self._instrument_id_instrument_lock:
                 return self._instrument_id_instrument[instrument_id]
 
-        instrument = UpDownCounter(
+        instrument = _UpDownCounter(
             name,
             self._instrumentation_scope,
             self._measurement_consumer,
@@ -147,7 +147,7 @@ def create_observable_counter(
             is_instrument_registered,
             instrument_id,
         ) = self._is_instrument_registered(
-            name, ObservableCounter, unit, description
+            name, _ObservableCounter, unit, description
         )
 
         if is_instrument_registered:
@@ -165,7 +165,7 @@ def create_observable_counter(
             with self._instrument_id_instrument_lock:
                 return self._instrument_id_instrument[instrument_id]
 
-        instrument = ObservableCounter(
+        instrument = _ObservableCounter(
             name,
             self._instrumentation_scope,
             self._measurement_consumer,
@@ -185,7 +185,7 @@ def create_histogram(self, name, unit="", description="") -> APIHistogram:
         (
             is_instrument_registered,
             instrument_id,
-        ) = self._is_instrument_registered(name, Histogram, unit, description)
+        ) = self._is_instrument_registered(name, _Histogram, unit, description)
 
         if is_instrument_registered:
             # FIXME #2558 go through all views here and check if this
@@ -202,7 +202,7 @@ def create_histogram(self, name, unit="", description="") -> APIHistogram:
             with self._instrument_id_instrument_lock:
                 return self._instrument_id_instrument[instrument_id]
 
-        instrument = Histogram(
+        instrument = _Histogram(
             name,
             self._instrumentation_scope,
             self._measurement_consumer,
@@ -221,7 +221,7 @@ def create_observable_gauge(
             is_instrument_registered,
             instrument_id,
         ) = self._is_instrument_registered(
-            name, ObservableGauge, unit, description
+            name, _ObservableGauge, unit, description
         )
 
         if is_instrument_registered:
@@ -239,7 +239,7 @@ def create_observable_gauge(
             with self._instrument_id_instrument_lock:
                 return self._instrument_id_instrument[instrument_id]
 
-        instrument = ObservableGauge(
+        instrument = _ObservableGauge(
             name,
             self._instrumentation_scope,
             self._measurement_consumer,
@@ -261,7 +261,9 @@ def create_observable_up_down_counter(
         (
             is_instrument_registered,
             instrument_id,
-        ) = self._is_instrument_registered(name, Counter, unit, description)
+        ) = self._is_instrument_registered(
+            name, _ObservableUpDownCounter, unit, description
+        )
 
         if is_instrument_registered:
             # FIXME #2558 go through all views here and check if this
@@ -278,7 +280,7 @@ def create_observable_up_down_counter(
             with self._instrument_id_instrument_lock:
                 return self._instrument_id_instrument[instrument_id]
 
-        instrument = ObservableUpDownCounter(
+        instrument = _ObservableUpDownCounter(
             name,
             self._instrumentation_scope,
             self._measurement_consumer,

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

@@ -45,6 +45,12 @@
     ObservableGauge,
     ObservableUpDownCounter,
     UpDownCounter,
+    _Counter,
+    _Histogram,
+    _ObservableCounter,
+    _ObservableGauge,
+    _ObservableUpDownCounter,
+    _UpDownCounter,
 )
 from opentelemetry.sdk.metrics._internal.point import MetricsData
 from opentelemetry.util._once import Once
@@ -164,6 +170,7 @@ class MetricReader(ABC):
     # FIXME add :std:envvar:`OTEL_EXPORTER_OTLP_METRICS_TEMPORALITY_PREFERENCE`
     # to the end of the documentation paragraph above.
 
+    # pylint: disable=too-many-branches
     def __init__(
         self,
         preferred_temporality: Dict[type, AggregationTemporality] = None,
@@ -189,22 +196,22 @@ def __init__(
             == "DELTA"
         ):
             self._instrument_class_temporality = {
-                Counter: AggregationTemporality.DELTA,
-                UpDownCounter: AggregationTemporality.CUMULATIVE,
-                Histogram: AggregationTemporality.DELTA,
-                ObservableCounter: AggregationTemporality.DELTA,
-                ObservableUpDownCounter: AggregationTemporality.CUMULATIVE,
-                ObservableGauge: AggregationTemporality.CUMULATIVE,
+                _Counter: AggregationTemporality.DELTA,
+                _UpDownCounter: AggregationTemporality.CUMULATIVE,
+                _Histogram: AggregationTemporality.DELTA,
+                _ObservableCounter: AggregationTemporality.DELTA,
+                _ObservableUpDownCounter: AggregationTemporality.CUMULATIVE,
+                _ObservableGauge: AggregationTemporality.CUMULATIVE,
             }
 
         else:
             self._instrument_class_temporality = {
-                Counter: AggregationTemporality.CUMULATIVE,
-                UpDownCounter: AggregationTemporality.CUMULATIVE,
-                Histogram: AggregationTemporality.CUMULATIVE,
-                ObservableCounter: AggregationTemporality.CUMULATIVE,
-                ObservableUpDownCounter: AggregationTemporality.CUMULATIVE,
-                ObservableGauge: AggregationTemporality.CUMULATIVE,
+                _Counter: AggregationTemporality.CUMULATIVE,
+                _UpDownCounter: AggregationTemporality.CUMULATIVE,
+                _Histogram: AggregationTemporality.CUMULATIVE,
+                _ObservableCounter: AggregationTemporality.CUMULATIVE,
+                _ObservableUpDownCounter: AggregationTemporality.CUMULATIVE,
+                _ObservableGauge: AggregationTemporality.CUMULATIVE,
             }
 
         if preferred_temporality is not None:
@@ -217,18 +224,69 @@ def __init__(
                         f"Invalid temporality value found {temporality}"
                     )
 
-        self._instrument_class_temporality.update(preferred_temporality or {})
+        if preferred_temporality is not None:
+            for typ, temporality in preferred_temporality.items():
+                if typ is Counter:
+                    self._instrument_class_temporality[_Counter] = temporality
+                elif typ is UpDownCounter:
+                    self._instrument_class_temporality[
+                        _UpDownCounter
+                    ] = temporality
+                elif typ is Histogram:
+                    self._instrument_class_temporality[
+                        _Histogram
+                    ] = temporality
+                elif typ is ObservableCounter:
+                    self._instrument_class_temporality[
+                        _ObservableCounter
+                    ] = temporality
+                elif typ is ObservableUpDownCounter:
+                    self._instrument_class_temporality[
+                        _ObservableUpDownCounter
+                    ] = temporality
+                elif typ is ObservableGauge:
+                    self._instrument_class_temporality[
+                        _ObservableGauge
+                    ] = temporality
+                else:
+                    raise Exception(f"Invalid instrument class found {typ}")
+
         self._preferred_temporality = preferred_temporality
         self._instrument_class_aggregation = {
-            Counter: DefaultAggregation(),
-            UpDownCounter: DefaultAggregation(),
-            Histogram: DefaultAggregation(),
-            ObservableCounter: DefaultAggregation(),
-            ObservableUpDownCounter: DefaultAggregation(),
-            ObservableGauge: DefaultAggregation(),
+            _Counter: DefaultAggregation(),
+            _UpDownCounter: DefaultAggregation(),
+            _Histogram: DefaultAggregation(),
+            _ObservableCounter: DefaultAggregation(),
+            _ObservableUpDownCounter: DefaultAggregation(),
+            _ObservableGauge: DefaultAggregation(),
         }
 
-        self._instrument_class_aggregation.update(preferred_aggregation or {})
+        if preferred_aggregation is not None:
+            for typ, aggregation in preferred_aggregation.items():
+                if typ is Counter:
+                    self._instrument_class_aggregation[_Counter] = aggregation
+                elif typ is UpDownCounter:
+                    self._instrument_class_aggregation[
+                        _UpDownCounter
+                    ] = aggregation
+                elif typ is Histogram:
+                    self._instrument_class_aggregation[
+                        _Histogram
+                    ] = aggregation
+                elif typ is ObservableCounter:
+                    self._instrument_class_aggregation[
+                        _ObservableCounter
+                    ] = aggregation
+                elif typ is ObservableUpDownCounter:
+                    self._instrument_class_aggregation[
+                        _ObservableUpDownCounter
+                    ] = aggregation
+                elif typ is ObservableGauge:
+                    self._instrument_class_aggregation[
+                        _ObservableGauge
+                    ] = aggregation
+                else:
+                    raise Exception(f"Invalid instrument class found {typ}")
 
     @final
     def collect(self, timeout_millis: float = 10_000) -> None:

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

@@ -132,6 +132,11 @@ def callback(
 
 
 class Counter(_Synchronous, APICounter):
+    def __new__(cls, *args, **kwargs):
+        if cls is Counter:
+            raise TypeError("Counter must be instantiated via a meter.")
+        return super().__new__(cls)
+
     def add(
         self, amount: Union[int, float], attributes: Dict[str, str] = None
     ):
@@ -146,6 +151,11 @@ def add(
 
 
 class UpDownCounter(_Synchronous, APIUpDownCounter):
+    def __new__(cls, *args, **kwargs):
+        if cls is UpDownCounter:
+            raise TypeError("UpDownCounter must be instantiated via a meter.")
+        return super().__new__(cls)
+
     def add(
         self, amount: Union[int, float], attributes: Dict[str, str] = None
     ):
@@ -155,14 +165,29 @@ def add(
 
 
 class ObservableCounter(_Asynchronous, APIObservableCounter):
-    pass
+    def __new__(cls, *args, **kwargs):
+        if cls is ObservableCounter:
+            raise TypeError(
+                "ObservableCounter must be instantiated via a meter."
+            )
+        return super().__new__(cls)
 
 
 class ObservableUpDownCounter(_Asynchronous, APIObservableUpDownCounter):
-    pass
+    def __new__(cls, *args, **kwargs):
+        if cls is ObservableUpDownCounter:
+            raise TypeError(
+                "ObservableUpDownCounter must be instantiated via a meter."
+            )
+        return super().__new__(cls)
 
 
 class Histogram(_Synchronous, APIHistogram):
+    def __new__(cls, *args, **kwargs):
+        if cls is Histogram:
+            raise TypeError("Histogram must be instantiated via a meter.")
+        return super().__new__(cls)
+
     def record(
         self, amount: Union[int, float], attributes: Dict[str, str] = None
     ):
@@ -178,4 +203,34 @@ def record(
 
 
 class ObservableGauge(_Asynchronous, APIObservableGauge):
+    def __new__(cls, *args, **kwargs):
+        if cls is ObservableGauge:
+            raise TypeError(
+                "ObservableGauge must be instantiated via a meter."
+            )
+        return super().__new__(cls)
+
+
+# Below classes exist to prevent the direct instantiation
+class _Counter(Counter):
+    pass
+
+
+class _UpDownCounter(UpDownCounter):
+    pass
+
+
+class _ObservableCounter(ObservableCounter):
+    pass
+
+
+class _ObservableUpDownCounter(ObservableUpDownCounter):
+    pass
+
+
+class _Histogram(Histogram):
+    pass
+
+
+class _ObservableGauge(ObservableGauge):
     pass