disable when powertools dev

Author: anafalcao

aws_lambda_powertools/metrics/provider/cloudwatch_emf/cloudwatch.py

@@ -90,15 +90,23 @@ def __init__(
 
     @staticmethod
     def is_metrics_disabled() -> bool:
-        """Checks if metrics have been disabled via POWERTOOLS_METRICS_DISABLED"""
-        if constants.METRICS_DISABLED_ENV not in os.environ:
-            return False
-
-        env_value = os.getenv(constants.METRICS_DISABLED_ENV)
-        is_disabled = resolve_truthy_env_var_choice(env=env_value or "false")
-        if is_disabled:
-            logger.debug("Metrics have been disabled via env var POWERTOOLS_METRICS_DISABLED")
-        return bool(is_disabled)
+        """Checks if metrics have been disabled via POWERTOOLS_METRICS_DISABLED or POWERTOOLS_DEV"""
+        # First check POWERTOOLS_METRICS_DISABLED
+        if constants.METRICS_DISABLED_ENV in os.environ:
+            env_value = os.getenv(constants.METRICS_DISABLED_ENV)
+            is_disabled = resolve_truthy_env_var_choice(env=env_value or "false")
+            if is_disabled:
+                logger.debug("Metrics have been disabled via env var POWERTOOLS_METRICS_DISABLED")
+            return bool(is_disabled)
+
+        # Then check if POWERTOOLS_DEV is enabled
+        dev_mode_value = os.getenv(constants.POWERTOOLS_DEV_ENV)
+        dev_mode = resolve_truthy_env_var_choice(env=dev_mode_value or "false")
+        if dev_mode:
+            logger.debug("Metrics have been disabled via env var POWERTOOLS_DEV")
+            return True
+
+        return False
 
     def add_metric(
         self,

aws_lambda_powertools/metrics/provider/datadog/datadog.py

@@ -69,7 +69,15 @@ def __init__(
 
     @staticmethod
     def is_metrics_disabled() -> bool:
-        """Checks if metrics have been disabled via POWERTOOLS_METRICS_DISABLED"""
+        """Checks if metrics have been disabled via POWERTOOLS_METRICS_DISABLED or POWERTOOLS_DEV"""
+        # First check if POWERTOOLS_DEV is enabled
+        dev_mode_value = os.getenv(constants.POWERTOOLS_DEV_ENV)
+        dev_mode = resolve_truthy_env_var_choice(env=dev_mode_value or "false")
+        if dev_mode:
+            logger.debug("Metrics have been disabled via env var POWERTOOLS_DEV")
+            return True
+
+        # Then check POWERTOOLS_METRICS_DISABLED
         if constants.METRICS_DISABLED_ENV not in os.environ:
             return False
 

docs/index.md

@@ -432,6 +432,7 @@ When `POWERTOOLS_DEV` is set to a truthy value (`1`, `true`), it'll have the fol
 | __Logger__        | Increase JSON indentation to 4. This will ease local debugging when running functions locally under emulators or direct calls while not affecting unit tests. <br><br> However, Amazon CloudWatch Logs view will degrade as each new line is treated as a new message. |
 | __Event Handler__ | Enable full traceback errors in the response, indent request/responses, and CORS in dev mode (`*`).                                                                                                                                                                    |
 | __Tracer__        | Future-proof safety to disables tracing operations in non-Lambda environments. This already happens automatically in the Tracer utility.                                                                                                                               |
+| __Metrics__      | Disables Powertools metrics emission by default. <br><br> However, this can be overridden by explicitly setting POWERTOOLS_METRICS_DISABLED=false, which takes precedence over the dev mode setting.                                                                                                                               |
 
 ## Debug mode
 

tests/functional/metrics/datadog/test_metrics_datadog.py

@@ -336,7 +336,6 @@ def test_namespace_env_var(monkeypatch):
     assert output[0]["m"] == f"{env_namespace}.item_sold"
 
 
-####################
 def test_metrics_disabled_with_env_var(monkeypatch):
     # GIVEN environment variable is set to disable metrics
     monkeypatch.setenv("POWERTOOLS_METRICS_DISABLED", "true")
@@ -412,3 +411,82 @@ def test_metrics_enabled_with_env_var_not_set(monkeypatch, capsys):
     metrics_output = json.loads(output)
 
     assert "test.test_metric" in metrics_output["m"]
+
+
+def test_metrics_disabled_with_dev_mode_true(monkeypatch, capsys):
+    # GIVEN dev mode is enabled
+    monkeypatch.setenv("POWERTOOLS_DEV", "true")
+
+    # WHEN metrics is initialized
+    metrics = DatadogMetrics(namespace="test")
+    metrics.add_metric(name="test_metric", value=1)
+
+    # AND flushing metrics
+    metrics_output = metrics.flush_metrics()
+
+    # THEN metrics output should be empty
+    assert metrics_output is None
+
+
+def test_metrics_enabled_with_dev_mode_false(monkeypatch, capsys):
+    # GIVEN dev mode is disabled
+    monkeypatch.setenv("POWERTOOLS_DEV", "false")
+
+    # WHEN metrics is initialized
+    metrics = DatadogMetrics(namespace="test")
+    metrics.add_metric(name="test_metric", value=1)
+    metrics.flush_metrics()
+
+    # THEN metrics should be written to stdout
+    output = capsys.readouterr().out
+    metrics_output = json.loads(output)
+    assert metrics_output
+
+
+def test_metrics_disabled_dev_mode_overrides_metrics_disabled(monkeypatch, capsys):
+    # GIVEN dev mode is enabled but metrics disabled is false
+    monkeypatch.setenv("POWERTOOLS_DEV", "true")
+    monkeypatch.setenv("POWERTOOLS_METRICS_DISABLED", "false")
+
+    # WHEN metrics is initialized
+    metrics = DatadogMetrics(namespace="test")
+    metrics.add_metric(name="test_metric", value=1)
+    metrics.flush_metrics()
+
+    # THEN metrics should be written to stdout (POWERTOOLS_METRICS_DISABLED takes precedence)
+    output = capsys.readouterr().out
+    metrics_output = json.loads(output)
+    assert metrics_output
+
+
+def test_metrics_enabled_with_both_false(monkeypatch, capsys):
+    # GIVEN both dev mode and metrics disabled are false
+    monkeypatch.setenv("POWERTOOLS_DEV", "false")
+    monkeypatch.setenv("POWERTOOLS_METRICS_DISABLED", "false")
+
+    # WHEN metrics is initialized
+    metrics = DatadogMetrics(namespace="test")
+    metrics.add_metric(name="test_metric", value=1)
+    metrics.flush_metrics()
+
+    # THEN metrics should be written to stdout
+    output = capsys.readouterr().out
+    metrics_output = json.loads(output)
+    assert metrics_output
+
+
+def test_metrics_disabled_with_dev_mode_false_and_metrics_disabled_true(monkeypatch):
+    # GIVEN dev mode is false but metrics disabled is true
+    monkeypatch.setenv("POWERTOOLS_DEV", "false")
+    monkeypatch.setenv("POWERTOOLS_METRICS_DISABLED", "true")
+
+    # WHEN metrics is initialized
+    metrics = DatadogMetrics(namespace="test")
+
+    metrics.add_metric(name="test_metric", value=1)
+
+    # WHEN flushing metrics
+    metrics_output = metrics.flush_metrics()
+
+    # THEN metrics output should be empty
+    assert metrics_output is None

tests/functional/metrics/required_dependencies/test_metrics_cloudwatch_emf.py

@@ -1412,3 +1412,70 @@ def test_metrics_enabled_with_env_var_not_set(monkeypatch, capsys):
     assert metrics_output["test_metric"] == [1.0]
     assert metrics_output["_aws"]["CloudWatchMetrics"][0]["Namespace"] == "test"
     assert metrics_output["_aws"]["CloudWatchMetrics"][0]["Metrics"][0]["Name"] == "test_metric"
+
+
+def test_metrics_disabled_with_dev_mode(monkeypatch, namespace):
+    # GIVEN environment variable is set to disable metrics
+    monkeypatch.setenv("POWERTOOLS_DEV", "true")
+
+    # WHEN metrics is initialized and adding metrics
+    metrics = Metrics(namespace=namespace)
+    metrics.add_metric(name="test_metric", unit="Count", value=1)
+
+    # AND flushing metrics
+    metrics_output = metrics.flush_metrics()
+
+    # THEN metrics output should be empty
+    assert metrics_output is None
+
+
+def test_metrics_enabled_with_dev_mode_false(monkeypatch, capsys):
+    # GIVEN environment variable is set to enable metrics
+    monkeypatch.setenv("POWERTOOLS_DEV", "false")
+
+    # WHEN metrics is initialized with namespace and metrics added
+    metrics = Metrics(namespace="test")
+    metrics.add_metric(name="test_metric", unit="Count", value=1)
+    metrics.flush_metrics()
+
+    # THEN metrics should be written to stdout
+    output = capsys.readouterr().out
+    metrics_output = json.loads(output)
+
+    assert "test_metric" in metrics_output
+    assert metrics_output["test_metric"] == [1.0]
+    assert metrics_output["_aws"]["CloudWatchMetrics"][0]["Namespace"] == "test"
+    assert metrics_output["_aws"]["CloudWatchMetrics"][0]["Metrics"][0]["Name"] == "test_metric"
+
+
+def test_metrics_dev_mode_does_not_override_metrics_disabled(monkeypatch, capsys):
+    # GIVEN dev mode is enabled but metrics disabled is explicitly false
+    monkeypatch.setenv("POWERTOOLS_DEV", "true")
+    monkeypatch.setenv("POWERTOOLS_METRICS_DISABLED", "false")
+
+    # WHEN metrics is initialized
+    metrics = Metrics(namespace="test")
+    metrics.add_metric(name="test_metric", value=1, unit="Count")
+    metrics.flush_metrics()
+
+    # THEN metrics should be written to stdout (POWERTOOLS_METRICS_DISABLED takes precedence)
+    output = capsys.readouterr().out
+    metrics_output = json.loads(output)
+    assert metrics_output
+
+
+def test_metrics_disabled_with_dev_mode_false_and_metrics_disabled_true(monkeypatch):
+    # GIVEN dev mode is false but metrics disabled is true
+    monkeypatch.setenv("POWERTOOLS_DEV", "false")
+    monkeypatch.setenv("POWERTOOLS_METRICS_DISABLED", "true")
+
+    # WHEN metrics is initialized
+    metrics = Metrics(namespace="test")
+
+    metrics.add_metric(name="test_metric", value=1, unit="Count")
+
+    # WHEN flushing metrics
+    metrics_output = metrics.flush_metrics()
+
+    # THEN metrics output should be empty
+    assert metrics_output is None