Add Azure Kubernetes Service resource detector

.codespellrc

@@ -1,4 +1,4 @@
 [codespell]
 # skipping auto generated folders
 skip = ./.tox,./.mypy_cache,./docs/_build,./target,*/LICENSE,./venv,*/cassettes
-ignore-words-list = ot
+ignore-words-list = aks,ot

resource/opentelemetry-resource-detector-azure/.changelog/5012.added

@@ -0,0 +1 @@
+`opentelemetry-resource-detector-azure`: add AKS resource detector

resource/opentelemetry-resource-detector-azure/README.rst

@@ -7,6 +7,7 @@ OpenTelemetry Resource detectors for Azure
    :target: https://pypi.org/project/opentelemetry-resource-detector-azure/
 
 This library contains OpenTelemetry `Resource Detectors <https://opentelemetry.io/docs/specs/otel/resource/sdk/#detecting-resource-information-from-the-environment>`_ for the following Azure resources:
+ * `Azure Kubernetes Service <https://azure.microsoft.com/en-us/products/kubernetes-service>`_
  * `Azure App Service <https://azure.microsoft.com/en-us/products/app-service>`_
  * `Azure Virtual Machines <https://azure.microsoft.com/en-us/products/virtual-machines>`_
  * `Azure Functions (Experimental) <https://azure.microsoft.com/en-us/products/functions>`_
@@ -26,10 +27,9 @@ Usage example for ``opentelemetry-resource-detector-azure``
 
     from opentelemetry import trace
     from opentelemetry.sdk.trace import TracerProvider
-    from opentelemetry.resource.detector.azure.app_service import (
+    from opentelemetry.resource.detector.azure import (
+        AzureAKSResourceDetector,
         AzureAppServiceResourceDetector,
-    )
-    from opentelemetry.resource.detector.azure.vm import (
         AzureVMResourceDetector,
     )
     from opentelemetry.sdk.resources import get_aggregated_resources
@@ -39,6 +39,7 @@ Usage example for ``opentelemetry-resource-detector-azure``
         TracerProvider(
             resource=get_aggregated_resources(
                 [
+                    AzureAKSResourceDetector(),
                     AzureAppServiceResourceDetector(),
                     AzureVMResourceDetector(),
                 ]
@@ -49,6 +50,43 @@ Usage example for ``opentelemetry-resource-detector-azure``
 Mappings
 --------
 
+The Azure Kubernetes Service Resource Detector reads the cluster resource ID from the
+``CLUSTER_RESOURCE_ID`` environment variable or from a mounted ``aks-cluster-metadata``
+ConfigMap at ``/etc/kubernetes/aks-cluster-metadata``. It sets the following Resource
+Attributes:
+
+ * ``cloud.platform`` set to ``azure_aks``.
+ * ``cloud.provider`` set to ``azure``.
+ * ``cloud.resource_id`` set to the full Azure Resource Manager cluster resource ID.
+
+The native AKS ConfigMap is named ``aks-cluster-metadata`` and contains a
+``clusterResourceId`` key. It can be exposed to a pod as an environment variable:
+
+.. code-block:: yaml
+
+    env:
+      - name: CLUSTER_RESOURCE_ID
+        valueFrom:
+          configMapKeyRef:
+            name: aks-cluster-metadata
+            key: clusterResourceId
+
+Alternatively, mount the ConfigMap as a volume:
+
+.. code-block:: yaml
+
+    volumes:
+      - name: aks-cluster-metadata
+        configMap:
+          name: aks-cluster-metadata
+    volumeMounts:
+      - name: aks-cluster-metadata
+        mountPath: /etc/kubernetes/aks-cluster-metadata
+
+Kubernetes resolves ConfigMap references within the pod's namespace. Because the native
+ConfigMap is in ``kube-public``, copy it into the workload namespace or use tooling such
+as an init container to expose its value through one of the supported locations.
+
 The Azure App Service Resource Detector sets the following Resource Attributes:
  * ``service.name`` set to the value of the ``WEBSITE_SITE_NAME`` environment variable.
  * ``cloud.platform`` set to ``azure_app_service``.

resource/opentelemetry-resource-detector-azure/pyproject.toml

@@ -30,6 +30,7 @@ dependencies = [
 ]
 
 [project.entry-points.opentelemetry_resource_detector]
+azure_aks = "opentelemetry.resource.detector.azure.aks:AzureAKSResourceDetector"
 azure_app_service = "opentelemetry.resource.detector.azure.app_service:AzureAppServiceResourceDetector"
 azure_functions = "opentelemetry.resource.detector.azure.functions:AzureFunctionsResourceDetector"
 azure_vm = "opentelemetry.resource.detector.azure.vm:AzureVMResourceDetector"

resource/opentelemetry-resource-detector-azure/src/opentelemetry/resource/detector/azure/__init__.py

@@ -3,12 +3,14 @@
 
 # pylint: disable=import-error
 
+from .aks import AzureAKSResourceDetector
 from .app_service import AzureAppServiceResourceDetector
 from .functions import AzureFunctionsResourceDetector
 from .version import __version__
 from .vm import AzureVMResourceDetector
 
 __all__ = [
+    "AzureAKSResourceDetector",
     "AzureAppServiceResourceDetector",
     "AzureFunctionsResourceDetector",
     "AzureVMResourceDetector",

resource/opentelemetry-resource-detector-azure/src/opentelemetry/resource/detector/azure/_constants.py

@@ -8,6 +8,9 @@
 # Azure Kubernetes
 
 _AKS_ARM_NAMESPACE_ID = "AKS_ARM_NAMESPACE_ID"
+_AKS_CLUSTER_RESOURCE_ID = "CLUSTER_RESOURCE_ID"
+_AKS_CLUSTER_RESOURCE_ID_KEY = "clusterResourceId"
+_AKS_METADATA_FILE_PATH = "/etc/kubernetes/aks-cluster-metadata"
 
 # AppService
 

resource/opentelemetry-resource-detector-azure/src/opentelemetry/resource/detector/azure/_utils.py

@@ -1,9 +1,12 @@
 # Copyright The OpenTelemetry Authors
 # SPDX-License-Identifier: Apache-2.0
 from os import environ
+from pathlib import Path
 
 from ._constants import (
     _AKS_ARM_NAMESPACE_ID,
+    _AKS_CLUSTER_RESOURCE_ID,
+    _AKS_METADATA_FILE_PATH,
     _FUNCTIONS_WORKER_RUNTIME,
     _WEBSITE_OWNER_NAME,
     _WEBSITE_RESOURCE_GROUP,
@@ -12,7 +15,11 @@
 
 
 def _is_on_aks() -> bool:
-    return environ.get(_AKS_ARM_NAMESPACE_ID) is not None
+    return (
+        environ.get(_AKS_ARM_NAMESPACE_ID) is not None
+        or environ.get(_AKS_CLUSTER_RESOURCE_ID) is not None
+        or Path(_AKS_METADATA_FILE_PATH).exists()
+    )
 
 
 def _is_on_app_service() -> bool:

resource/opentelemetry-resource-detector-azure/src/opentelemetry/resource/detector/azure/aks.py

@@ -0,0 +1,86 @@
+# Copyright The OpenTelemetry Authors
+# SPDX-License-Identifier: Apache-2.0
+
+from logging import getLogger
+from os import environ
+from pathlib import Path
+
+from opentelemetry.sdk.resources import Resource, ResourceDetector
+
+from ._constants import (
+    _AKS_CLUSTER_RESOURCE_ID,
+    _AKS_CLUSTER_RESOURCE_ID_KEY,
+    _AKS_METADATA_FILE_PATH,
+)
+
+_logger = getLogger(__name__)
+
+_CLOUD_ACCOUNT_ID = "cloud.account.id"
+_CLOUD_PLATFORM = "cloud.platform"
+_CLOUD_PROVIDER = "cloud.provider"
+_CLOUD_RESOURCE_ID = "cloud.resource_id"
+
+
+def _extract_subscription_id(resource_id: str) -> str | None:
+    segments = resource_id.split("/")
+    for index, segment in enumerate(segments):
+        if segment.lower() == "subscriptions" and index < len(segments) - 1:
+            return segments[index + 1] or None
+    return None
+
+
+def _parse_aks_metadata(content: str) -> str | None:
+    keyed_resource_id: str | None = None
+    bare_values: list[str] = []
+
+    for line in content.splitlines():
+        stripped_line = line.strip().lstrip("\ufeff")
+        if not stripped_line or stripped_line.startswith("#"):
+            continue
+
+        key, separator, value = stripped_line.partition("=")
+        if not separator:
+            bare_values.append(stripped_line)
+        elif key.strip() == _AKS_CLUSTER_RESOURCE_ID_KEY and value.strip():
+            keyed_resource_id = value.strip()
+
+    if keyed_resource_id:
+        return keyed_resource_id
+    if len(bare_values) == 1:
+        return bare_values[0]
+    return None
+
+
+def _get_aks_metadata_from_file() -> str | None:
+    metadata_path = Path(_AKS_METADATA_FILE_PATH)
+    try:
+        if metadata_path.is_dir():
+            metadata_path = metadata_path / _AKS_CLUSTER_RESOURCE_ID_KEY
+        content = metadata_path.read_text(encoding="utf-8")
+    except (OSError, UnicodeError):
+        _logger.debug(
+            "Failed to read AKS metadata from %s",
+            metadata_path,
+            exc_info=True,
+        )
+        return None
+
+    return _parse_aks_metadata(content)
+
+
+class AzureAKSResourceDetector(ResourceDetector):
+    def detect(self) -> Resource:
+        resource_id = environ.get(_AKS_CLUSTER_RESOURCE_ID) or _get_aks_metadata_from_file()
+        if not resource_id:
+            return Resource({})
+
+        attributes = {
+            _CLOUD_PROVIDER: "azure",
+            _CLOUD_PLATFORM: "azure.aks",
+            _CLOUD_RESOURCE_ID: resource_id,
+        }
+        subscription_id = _extract_subscription_id(resource_id)
+        if subscription_id:
+            attributes[_CLOUD_ACCOUNT_ID] = subscription_id
+
+        return Resource(attributes)