Adds metrics API

CHANGELOG.md

@@ -6,6 +6,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased](https://github.com/open-telemetry/opentelemetry-python/compare/v1.5.0-0.24b0...HEAD)
 
+- Add metrics API
+  ([#1887](https://github.com/open-telemetry/opentelemetry-python/pull/1887))
 - `opentelemetry-semantic-conventions` Update to semantic conventions v1.6.1
   ([#2077](https://github.com/open-telemetry/opentelemetry-python/pull/2077))
 - Do not count invalid attributes for dropped

docs/api/api.rst

@@ -9,4 +9,5 @@ OpenTelemetry Python API
     baggage
     context
     trace
+    metrics
     environment_variables

docs/api/metrics.instrument.rst

@@ -0,0 +1,8 @@
+opentelemetry.metrics.instrument
+================================
+
+.. automodule:: opentelemetry.metrics.instrument
+    :members:
+    :private-members:
+    :undoc-members:
+    :show-inheritance:

docs/api/metrics.measurement.rst

@@ -0,0 +1,7 @@
+opentelemetry.metrics.measurement
+=================================
+
+.. automodule:: opentelemetry.metrics.measurement
+    :members:
+    :undoc-members:
+    :show-inheritance:

docs/api/metrics.rst

@@ -0,0 +1,15 @@
+opentelemetry.metrics package
+=============================
+
+Submodules
+----------
+
+.. toctree::
+
+   metrics.instrument
+   metrics.measurement
+
+Module contents
+---------------
+
+.. automodule:: opentelemetry.metrics

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

@@ -41,3 +41,14 @@
 """
 .. envvar:: OTEL_PYTHON_TRACER_PROVIDER
 """
+
+OTEL_PYTHON_METER_PROVIDER = "OTEL_PYTHON_METER_PROVIDER"
+"""
+.. envvar:: OTEL_PYTHON_METER_PROVIDER
+"""
+
+OTEL_METRICS_EXPORTER = "OTEL_METRICS_EXPORTER"
+"""
+.. envvar:: OTEL_METRICS_EXPORTER
+
+"""