Allow loading all resource detectors by setting OTEL_EXPERIMENTAL_RESOURCE_DETECTORS to * (#4819)

* Allow loading all resource detectors by setting `OTEL_EXPERIMENTAL_RESOURCE_DETECTORS` to `all`

* Add changelog

* Use `*` instead of `all`

Author: bschoenmaeckers

CHANGELOG.md

@@ -12,6 +12,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+- Allow loading all resource detectors by setting `OTEL_EXPERIMENTAL_RESOURCE_DETECTORS` to `*`
+  ([#4819](https://github.com/open-telemetry/opentelemetry-python/pull/4819))
 - `opentelemetry-sdk`: Fix the type hint of the `_metrics_data` property to allow `None`
   ([#4837](https://github.com/open-telemetry/opentelemetry-python/pull/4837)).
 - Regenerate opentelemetry-proto code with v1.9.0 release

opentelemetry-api/src/opentelemetry/util/_importlib_metadata.py

@@ -36,7 +36,7 @@ def _original_entry_points_cached():
     return original_entry_points()
 
 
-def entry_points(**params):
+def entry_points(**params) -> EntryPoints:
     """Replacement for importlib_metadata.entry_points that caches getting all the entry points.
 
     That part can be very slow, and OTel uses this function many times."""

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

@@ -70,7 +70,7 @@
 from json import dumps
 from os import environ
 from types import ModuleType
-from typing import List, Optional, cast
+from typing import List, Optional, Set, cast
 from urllib import parse
 
 from opentelemetry.attributes import BoundedAttributes
@@ -195,7 +195,7 @@ def create(
         if not attributes:
             attributes = {}
 
-        otel_experimental_resource_detectors = {"otel"}.union(
+        otel_experimental_resource_detectors: Set[str] = {"otel"}.union(
             {
                 otel_experimental_resource_detector.strip()
                 for otel_experimental_resource_detector in environ.get(
@@ -207,7 +207,11 @@ def create(
 
         resource_detectors: List[ResourceDetector] = []
 
-        resource_detector: str
+        if "*" in otel_experimental_resource_detectors:
+            otel_experimental_resource_detectors = entry_points(
+                group="opentelemetry_resource_detector"
+            ).names
+
         for resource_detector in otel_experimental_resource_detectors:
             try:
                 resource_detectors.append(

opentelemetry-sdk/tests/resources/test_resources.py

@@ -474,6 +474,7 @@ def test_service_name_env(self):
         self.assertEqual(resource.attributes["service.name"], "from-code")
 
 
+# pylint: disable=too-many-public-methods
 class TestOTELResourceDetector(unittest.TestCase):
     def setUp(self) -> None:
         environ[OTEL_RESOURCE_ATTRIBUTES] = ""
@@ -697,6 +698,31 @@ def test_resource_detector_entry_points_os(self):
         self.assertIn(OS_TYPE, resource.attributes)
         self.assertIn(OS_VERSION, resource.attributes)
 
+    @patch.dict(
+        environ, {OTEL_EXPERIMENTAL_RESOURCE_DETECTORS: "*"}, clear=True
+    )
+    def test_resource_detector_entry_points_all(self):
+        resource = Resource({}).create()
+
+        self.assertIn(
+            TELEMETRY_SDK_NAME,
+            resource.attributes,
+            "'otel' resource detector not enabled",
+        )
+        self.assertIn(
+            OS_TYPE, resource.attributes, "'os' resource detector not enabled"
+        )
+        self.assertIn(
+            HOST_ARCH,
+            resource.attributes,
+            "'host' resource detector not enabled",
+        )
+        self.assertIn(
+            PROCESS_RUNTIME_NAME,
+            resource.attributes,
+            "'process' resource detector not enabled",
+        )
+
     def test_resource_detector_entry_points_otel(self):
         """
         Test that OTELResourceDetector-resource-generated attributes are