Change meta data service timeout to 200ms (open-telemetry#2387)

Author: lzchen

resource/opentelemetry-resource-detector-azure/CHANGELOG.md

@@ -0,0 +1,15 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+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
+
+- Change meta data service timeout to 200ms
+  ([#2387](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/2387))
+
+## Version 0.1.2 (2024-01-25)
+
+- Initial CHANGELOG.md entry

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

@@ -71,10 +71,8 @@ def _get_azure_vm_metadata():
     request = Request(_AZURE_VM_METADATA_ENDPOINT)
     request.add_header("Metadata", "True")
     try:
-        # TODO: Changed to 4s to fit into OTel SDK's 5 second timeout.
-        # Lengthen or allow user input if issue is resolved.
-        # See https://github.com/open-telemetry/opentelemetry-python/issues/3644
-        with urlopen(request, timeout=4) as response:
+        # VM metadata service should not take more than 200ms on success case
+        with urlopen(request, timeout=0.2) as response:
             return loads(response.read())
     except URLError:
         # Not on Azure VM