Load environment variables as options for opentelemetry-instrument (#…

…1969)

CHANGELOG.md

@@ -5,7 +5,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased](https://github.com/open-telemetry/opentelemetry-python/compare/v1.5.0-0.24b0...HEAD)
-
+- Automatically load OTEL environment variables as options for `opentelemetry-instrument`
+  ([#1969](https://github.com/open-telemetry/opentelemetry-python/pull/1969))
 - `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

CONTRIBUTING.md

@@ -214,6 +214,16 @@ rather than conform to specific API names or argument patterns in the spec.
 
 For a deeper discussion, see: https://github.com/open-telemetry/opentelemetry-specification/issues/165
 
+### Environment Variables
+
+If you are adding a component that introduces new OpenTelemetry environment variables, put them all in a module,
+as it is done in `opentelemetry.environment_variables` or in `opentelemetry.sdk.environment_variables`.
+
+Keep in mind that any new environment variable must be declared in all caps and must start with `OTEL_PYTHON_`.
+
+Register this module with the `opentelemetry_environment_variables` entry point to make your environment variables
+automatically load as options for the `opentelemetry-instrument` command.
+
 ## Style Guide
 
 * docstrings should adhere to the [Google Python Style

opentelemetry-api/setup.cfg

@@ -56,6 +56,8 @@ opentelemetry_tracer_provider =
 opentelemetry_propagator =
     tracecontext = opentelemetry.trace.propagation.tracecontext:TraceContextTextMapPropagator
     baggage = opentelemetry.baggage.propagation:W3CBaggagePropagator
+opentelemetry_environment_variables =
+    api = opentelemetry.environment_variables
 
 [options.extras_require]
 test =

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

@@ -22,11 +22,6 @@
 .. envvar:: OTEL_PYTHON_CONTEXT
 """
 
-OTEL_PYTHON_DISABLED_INSTRUMENTATIONS = "OTEL_PYTHON_DISABLED_INSTRUMENTATIONS"
-"""
-.. envvar:: OTEL_PYTHON_DISABLED_INSTRUMENTATIONS
-"""
-
 OTEL_PYTHON_ID_GENERATOR = "OTEL_PYTHON_ID_GENERATOR"
 """
 .. envvar:: OTEL_PYTHON_ID_GENERATOR

opentelemetry-distro/src/opentelemetry/distro/__init__.py

@@ -11,7 +11,7 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-#
+
 import os
 
 from opentelemetry.environment_variables import OTEL_TRACES_EXPORTER

opentelemetry-instrumentation/setup.cfg

@@ -51,6 +51,8 @@ where = src
 console_scripts =
     opentelemetry-instrument = opentelemetry.instrumentation.auto_instrumentation:run
     opentelemetry-bootstrap = opentelemetry.instrumentation.bootstrap:run
+opentelemetry_environment_variables =
+    instrumentation = opentelemetry.instrumentation.environment_variables
 
 [options.extras_require]
 test =

opentelemetry-instrumentation/src/opentelemetry/instrumentation/auto_instrumentation/__init__.py

@@ -14,72 +14,74 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import argparse
+from argparse import REMAINDER, ArgumentParser
 from logging import getLogger
 from os import environ, execl, getcwd
 from os.path import abspath, dirname, pathsep
+from re import sub
 from shutil import which
 
-from opentelemetry.environment_variables import (
-    OTEL_PYTHON_ID_GENERATOR,
-    OTEL_TRACES_EXPORTER,
-)
+from pkg_resources import iter_entry_points
 
-logger = getLogger(__file__)
+_logger = getLogger(__file__)
 
 
-def parse_args():
-    parser = argparse.ArgumentParser(
+def run() -> None:
+
+    parser = ArgumentParser(
         description="""
         opentelemetry-instrument automatically instruments a Python
         program and its dependencies and then runs the program.
-        """
+        """,
+        epilog="""
+        Optional arguments (except for --help) for opentelemetry-instrument
+        directly correspond with OpenTelemetry environment variables. The
+        corresponding optional argument is formed by removing the OTEL_ or
+        OTEL_PYTHON_ prefix from the environment variable and lower casing the
+        rest. For example, the optional argument --attribute_value_length_limit
+        corresponds with the environment variable
+        OTEL_ATTRIBUTE_VALUE_LENGTH_LIMIT.
+
+        These optional arguments will override the current value of the
+        corresponding environment variable during the execution of the command.
+        """,
     )
 
-    parser.add_argument(
-        "--trace-exporter",
-        required=False,
-        help="""
-        Uses the specified exporter to export spans.
-        Accepts multiple exporters as comma separated values.
+    argument_otel_environment_variable = {}
 
-        Examples:
+    for entry_point in iter_entry_points(
+        "opentelemetry_environment_variables"
+    ):
+        environment_variable_module = entry_point.load()
 
-            --trace-exporter=jaeger
-        """,
-    )
+        for attribute in dir(environment_variable_module):
 
-    parser.add_argument(
-        "--id-generator",
-        required=False,
-        help="""
-        The IDs Generator to be used with the Tracer Provider.
+            if attribute.startswith("OTEL_"):
 
-        Examples:
+                argument = sub(r"OTEL_(PYTHON_)?", "", attribute).lower()
 
-            --id-generator=random
-        """,
-    )
+                parser.add_argument(
+                    f"--{argument}",
+                    required=False,
+                )
+                argument_otel_environment_variable[argument] = attribute
 
     parser.add_argument("command", help="Your Python application.")
     parser.add_argument(
         "command_args",
         help="Arguments for your application.",
-        nargs=argparse.REMAINDER,
+        nargs=REMAINDER,
     )
-    return parser.parse_args()
-
 
-def load_config_from_cli_args(args):
-    if args.trace_exporter:
-        environ[OTEL_TRACES_EXPORTER] = args.trace_exporter
-    if args.id_generator:
-        environ[OTEL_PYTHON_ID_GENERATOR] = args.id_generator
+    args = parser.parse_args()
 
+    for argument, otel_environment_variable in (
+        argument_otel_environment_variable
+    ).items():
+        value = getattr(args, argument)
+        if value is not None:
 
-def run() -> None:
-    args = parse_args()
-    load_config_from_cli_args(args)
+            environ[otel_environment_variable] = value
 
     python_path = environ.get("PYTHONPATH")
 

opentelemetry-instrumentation/src/opentelemetry/instrumentation/auto_instrumentation/sitecustomize.py

@@ -20,13 +20,13 @@
 
 from pkg_resources import iter_entry_points
 
-from opentelemetry.environment_variables import (
-    OTEL_PYTHON_DISABLED_INSTRUMENTATIONS,
-)
 from opentelemetry.instrumentation.dependencies import (
     get_dist_dependency_conflicts,
 )
 from opentelemetry.instrumentation.distro import BaseDistro, DefaultDistro
+from opentelemetry.instrumentation.environment_variables import (
+    OTEL_PYTHON_DISABLED_INSTRUMENTATIONS,
+)
 
 logger = getLogger(__file__)
 

opentelemetry-instrumentation/src/opentelemetry/instrumentation/environment_variables.py

@@ -0,0 +1,18 @@
+# Copyright The OpenTelemetry Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+OTEL_PYTHON_DISABLED_INSTRUMENTATIONS = "OTEL_PYTHON_DISABLED_INSTRUMENTATIONS"
+"""
+.. envvar:: OTEL_PYTHON_DISABLED_INSTRUMENTATIONS
+"""

opentelemetry-instrumentation/tests/test_run.py

@@ -111,7 +111,8 @@ def test_exporter(self, _):  # pylint: disable=no-self-use
             self.assertIsNone(environ.get(OTEL_TRACES_EXPORTER))
 
         with patch(
-            "sys.argv", ["instrument", "--trace-exporter", "jaeger", "1", "2"]
+            "sys.argv",
+            ["instrument", "--traces_exporter", "jaeger", "1", "2"],
         ):
             auto_instrumentation.run()
             self.assertEqual(environ.get(OTEL_TRACES_EXPORTER), "jaeger")

opentelemetry-sdk/setup.cfg

@@ -56,6 +56,8 @@ opentelemetry_traces_exporter =
     console = opentelemetry.sdk.trace.export:ConsoleSpanExporter
 opentelemetry_id_generator =
     random = opentelemetry.sdk.trace.id_generator:RandomIdGenerator
+opentelemetry_environment_variables =
+    sdk = opentelemetry.sdk.environment_variables
 
 [options.extras_require]
 test =