Read nf.container from NETFLIX_CONTAINER_NAME

spectator/common_tags.py

@@ -16,9 +16,14 @@ def _add_non_empty(tags: Dict[str, str], tag: str, *env_vars: str) -> None:
 
 def tags_from_env_vars() -> Dict[str, str]:
     """Extract common infrastructure tags from the Netflix environment variables, which are
-    specific to a process and thus cannot be managed by a shared SpectatorD instance."""
+    specific to a container or process and thus cannot be managed by a shared SpectatorD instance.
+
+      * `nf.container` - From `NETFLIX_CONTAINER_NAME`, falling back to `TITUS_CONTAINER_NAME`.
+      * `nf.process`   - From `NETFLIX_PROCESS_NAME`.
+
+    Values are stripped of whitespace, and unset or blank variables are ignored."""
     tags: Dict[str, str] = {}
-    _add_non_empty(tags, "nf.container", "TITUS_CONTAINER_NAME")
+    _add_non_empty(tags, "nf.container", "NETFLIX_CONTAINER_NAME", "TITUS_CONTAINER_NAME")
     _add_non_empty(tags, "nf.process", "NETFLIX_PROCESS_NAME")
     return tags
 

spectator/config.py

@@ -9,6 +9,13 @@ class Config:
     optional. The extra common tags are added to every metric, on top of the common tags provided
     by `spectatord`.
 
+    The `nf.container` tag (from `NETFLIX_CONTAINER_NAME`, falling back to `TITUS_CONTAINER_NAME`) and
+    the `nf.process` tag (from `NETFLIX_PROCESS_NAME`) are read from the environment when the Config is
+    created, and they take precedence over the same keys in the extra common tags. The Configs used by
+    `Registry()` and `GlobalRegistry` are created when `spectator` is imported, so set these variables
+    before that import, ideally in the process environment before it starts; changing `os.environ`
+    after the import has no effect on them.
+
     Possible values for `location` are:
 
       * `none`   - Configure a no-op writer that does nothing. Can be used to disable metrics collection.

tests/conftest.py

@@ -0,0 +1,7 @@
+import os
+
+# Remove the container and process names that the platform may inject into the environment, so that
+# tests which create a Config or Registry from the real environment get the expected tags on any host.
+# This runs before the test modules import spectator, which creates the GlobalRegistry at import time.
+for key in ["NETFLIX_CONTAINER_NAME", "NETFLIX_PROCESS_NAME", "TITUS_CONTAINER_NAME"]:
+    os.environ.pop(key, None)

tests/test_common_tags.py

@@ -21,14 +21,20 @@ def setup_environment() -> None:
 
     @staticmethod
     def clear_environment() -> None:
-        keys = ["NETFLIX_PROCESS_NAME", "TITUS_CONTAINER_NAME"]
+        keys = ["NETFLIX_CONTAINER_NAME", "NETFLIX_PROCESS_NAME", "TITUS_CONTAINER_NAME"]
 
         for key in keys:
             try:
                 del os.environ[key]
             except KeyError:
                 pass
 
+    def setUp(self) -> None:
+        self.clear_environment()
+
+    def tearDown(self) -> None:
+        self.clear_environment()
+
     def test_tags_from_env_vars(self):
         self.setup_environment()
         self.assertEqual(self.all_expected_tags(), tags_from_env_vars())
@@ -60,6 +66,52 @@ def test_tags_from_env_vars_whitespace_ignored(self):
         self.assertEqual(self.all_expected_tags(), tags_from_env_vars())
         self.clear_environment()
 
+    def test_tags_from_env_vars_netflix_container_name_preferred(self):
+        self.setup_environment()
+        os.environ["NETFLIX_CONTAINER_NAME"] = "app"
+
+        expected_tags = self.all_expected_tags()
+        expected_tags["nf.container"] = "app"
+        self.assertEqual(expected_tags, tags_from_env_vars())
+
+        self.clear_environment()
+
+    def test_tags_from_env_vars_netflix_container_name_blank_falls_back(self):
+        self.setup_environment()
+
+        os.environ["NETFLIX_CONTAINER_NAME"] = ""
+        self.assertEqual(self.all_expected_tags(), tags_from_env_vars())
+
+        os.environ["NETFLIX_CONTAINER_NAME"] = "  \t"
+        self.assertEqual(self.all_expected_tags(), tags_from_env_vars())
+
+        self.clear_environment()
+
+    def test_tags_from_env_vars_netflix_container_name_only(self):
+        self.setup_environment()
+        del os.environ["TITUS_CONTAINER_NAME"]
+        os.environ["NETFLIX_CONTAINER_NAME"] = "  app \t"
+
+        expected_tags = self.all_expected_tags()
+        expected_tags["nf.container"] = "app"
+        self.assertEqual(expected_tags, tags_from_env_vars())
+
+        self.clear_environment()
+
+    def test_tags_from_env_vars_process_empty_ignored(self):
+        self.setup_environment()
+        os.environ["NETFLIX_PROCESS_NAME"] = ""
+
+        expected_tags = self.all_expected_tags()
+        del expected_tags["nf.process"]
+        self.assertEqual(expected_tags, tags_from_env_vars())
+
+        self.clear_environment()
+
+    def test_tags_from_env_vars_none_set(self):
+        self.clear_environment()
+        self.assertEqual({}, tags_from_env_vars())
+
     def test_validate_tags(self):
         self.assertEqual({}, validate_tags({"": "empty key", 1: "non-string key"}))
         self.assertEqual({}, validate_tags({"empty val": "", "non-string val": 1}))

tests/test_config.py

@@ -21,14 +21,20 @@ def setup_environment() -> None:
 
     @staticmethod
     def clear_environment() -> None:
-        keys = ["NETFLIX_PROCESS_NAME", "SPECTATOR_OUTPUT_LOCATION", "TITUS_CONTAINER_NAME"]
+        keys = ["NETFLIX_CONTAINER_NAME", "NETFLIX_PROCESS_NAME", "SPECTATOR_OUTPUT_LOCATION", "TITUS_CONTAINER_NAME"]
 
         for key in keys:
             try:
                 del os.environ[key]
             except KeyError:
                 pass
 
+    def setUp(self) -> None:
+        self.clear_environment()
+
+    def tearDown(self) -> None:
+        self.clear_environment()
+
     @staticmethod
     def get_location(location: str) -> str:
         return Config(location).location
@@ -71,6 +77,13 @@ def test_extra_common_tags(self):
         self.assertEqual({"extra-tag": "foo", "nf.container": "main", "nf.process": "python"}, config.extra_common_tags)
         self.clear_environment()
 
+    def test_env_tags_override_extra_common_tags(self):
+        self.setup_environment()
+        os.environ["NETFLIX_CONTAINER_NAME"] = "app"
+        config = Config(extra_common_tags={"nf.container": "passed-in", "nf.process": "passed-in"})
+        self.assertEqual({"nf.container": "app", "nf.process": "python"}, config.extra_common_tags)
+        self.clear_environment()
+
     def test_valid_output_locations(self):
         self.assertEqual("none", self.get_location("none"))
         self.assertEqual("memory", self.get_location("memory"))