environment overrides

README.md

@@ -9,6 +9,7 @@ Generate CloudWatch Metrics embedded within structured log events. The embedded
 - [Installation](#installation)
 - [Usage](#usage)
 - [API](#api)
+- [Configuration](#configuration)
 - [Examples](#examples)
 - [Development](#development)
 
@@ -151,7 +152,7 @@ set_namespace("MyApplication");
 
 Flushes the current MetricsContext to the configured sink and resets all properties, dimensions and metric values. The namespace and default dimensions will be preserved across flushes.
 
-### Configuration
+## Configuration
 
 All configuration values can be set using environment variables with the prefix (`AWS_EMF_`). Configuration should be performed as close to application start up as possible.
 

aws_embedded_metrics/config/configuration.py

@@ -11,6 +11,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from aws_embedded_metrics.environment.environments import Environments
+
 
 class Configuration:
     def __init__(
@@ -22,6 +24,7 @@ def __init__(
         log_stream_name: str,
         agent_endpoint: str,
         ec2_metadata_endpoint: str = None,
+        environment: Environments = Environments.Unknown
     ):
         self.debug_logging_enabled = debug_logging_enabled
         self.service_name = service_name
@@ -30,3 +33,4 @@ def __init__(
         self.log_stream_name = log_stream_name
         self.agent_endpoint = agent_endpoint
         self.ec2_metadata_endpoint = ec2_metadata_endpoint
+        self.environment = environment

aws_embedded_metrics/config/environment_configuration_provider.py

@@ -13,6 +13,7 @@
 
 import os
 from aws_embedded_metrics.config.configuration import Configuration
+from aws_embedded_metrics.environment.environments import Environments
 
 ENV_VAR_PREFIX = "AWS_EMF"
 
@@ -23,6 +24,7 @@
 LOG_STREAM_NAME = "LOG_STREAM_NAME"
 AGENT_ENDPOINT = "AGENT_ENDPOINT"
 EC2_METADATA_ENDPOINT = "EC2_METADATA_ENDPOINT"
+ENVIRONMENT_OVERRIDE = "ENVIRONMENT"
 
 
 class EnvironmentConfigurationProvider:
@@ -39,6 +41,7 @@ def get_configuration(self) -> Configuration:
             self.__get_env_var(LOG_STREAM_NAME),
             self.__get_env_var(AGENT_ENDPOINT),
             self.__get_env_var(EC2_METADATA_ENDPOINT),
+            self.__get_environment_override(),
         )
 
     @staticmethod
@@ -54,3 +57,13 @@ def __get_bool_env_var(key: str) -> bool:
         if value is None:
             return False
         return value.lower() == "true"
+
+    @staticmethod
+    def __get_environment_override() -> Environments:
+        value = os.environ.get(f"{ENV_VAR_PREFIX}_{ENVIRONMENT_OVERRIDE}")
+        if value is not None and len(value) > 0:
+            try:
+                return Environments[value]
+            except Exception:
+                pass
+        return Environments.Unknown

aws_embedded_metrics/environment/environment_detector.py

@@ -13,14 +13,36 @@
 
 import logging
 from aws_embedded_metrics.environment import Environment
+from aws_embedded_metrics.environment.environments import Environments
 from aws_embedded_metrics.environment.default_environment import DefaultEnvironment
 from aws_embedded_metrics.environment.lambda_environment import LambdaEnvironment
 from aws_embedded_metrics.environment.ec2_environment import EC2Environment
+from aws_embedded_metrics.environment.local_environment import LocalEnvironment
+from aws_embedded_metrics import config
 from typing import Optional
 
 log = logging.getLogger(__name__)
 
-environments = [LambdaEnvironment(), EC2Environment()]
+lambda_environment = LambdaEnvironment()
+ec2_environment = EC2Environment()
+default_environment = DefaultEnvironment()
+local_environment = LocalEnvironment()
+
+environments = [lambda_environment, ec2_environment]
+Config = config.get_config()
+
+
+def get_environment_from_override() -> Environment:
+    if Config.environment == Environments.Agent:
+        return default_environment
+    if Config.environment == Environments.EC2:
+        return ec2_environment
+    if Config.environment == Environments.Lambda:
+        return lambda_environment
+    if Config.environment == Environments.Local:
+        return local_environment
+
+    return default_environment
 
 
 class EnvironmentCache:
@@ -32,6 +54,12 @@ async def resolve_environment() -> Environment:
         log.debug("Environment resolved from cache.")
         return EnvironmentCache.environment
 
+    if Config.environment is not Environments.Unknown and Config.environment is not None:
+        log.info("Environment override provided: %s", Config.environment)
+        environment_override = get_environment_from_override()
+        if environment_override is not None:
+            return environment_override
+
     for env_under_test in environments:
         is_environment = False
         try:
@@ -49,5 +77,5 @@ async def resolve_environment() -> Environment:
             return env_under_test
 
     log.info("No environment was detected. Using default.")
-    EnvironmentCache.environment = DefaultEnvironment()
+    EnvironmentCache.environment = default_environment
     return EnvironmentCache.environment

aws_embedded_metrics/environment/environments.py

@@ -0,0 +1,9 @@
+from enum import Enum
+
+
+class Environments(Enum):
+    Local = 1
+    Lambda = 2
+    Agent = 3
+    EC2 = 4
+    Unknown = -1

aws_embedded_metrics/environment/lambda_environment.py

@@ -14,7 +14,7 @@
 from aws_embedded_metrics.environment import Environment
 from aws_embedded_metrics.logger.metrics_context import MetricsContext
 from aws_embedded_metrics.sinks import Sink
-from aws_embedded_metrics.sinks.lambda_sink import LambdaSink
+from aws_embedded_metrics.sinks.console_sink import ConsoleSink
 import os
 
 
@@ -24,7 +24,7 @@ def get_env(key: str) -> str:
     return ""
 
 
-sink = LambdaSink()
+sink = ConsoleSink()
 
 
 class LambdaEnvironment(Environment):

aws_embedded_metrics/environment/local_environment.py

@@ -0,0 +1,54 @@
+# Copyright 2019 Amazon.com, Inc. or its affiliates.
+# Licensed under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from aws_embedded_metrics.environment import Environment
+from aws_embedded_metrics.logger.metrics_context import MetricsContext
+from aws_embedded_metrics.sinks import Sink
+from aws_embedded_metrics.sinks.console_sink import ConsoleSink
+from aws_embedded_metrics import config
+import os
+
+Config = config.get_config()
+
+
+def get_env(key: str) -> str:
+    if key in os.environ:
+        return os.environ[key]
+    return ""
+
+
+sink = ConsoleSink()
+
+
+class LocalEnvironment(Environment):
+    async def probe(self) -> bool:
+        # probe is not intended to be used in the LocalEnvironment
+        # To use the local environment you should set the environment
+        # override
+        return False
+
+    def get_name(self) -> str:
+        return Config.service_name or "Unknown"
+
+    def get_type(self) -> str:
+        return Config.service_type or "Local"
+
+    def get_log_group_name(self) -> str:
+        return Config.log_group_name or f"{self.get_name()}-metrics"
+
+    def configure_context(self, context: MetricsContext) -> None:
+        pass
+
+    def get_sink(self) -> Sink:
+        """Create the appropriate sink for this environment."""
+        return sink

aws_embedded_metrics/sinks/lambda_sink.py → aws_embedded_metrics/sinks/console_sink.py

@@ -17,7 +17,7 @@
 from aws_embedded_metrics.serializers.log_serializer import LogSerializer
 
 
-class LambdaSink(Sink):
+class ConsoleSink(Sink):
     def __init__(self, serializer: Serializer = LogSerializer()):
         self.serializer = serializer
 
@@ -26,4 +26,4 @@ def accept(self, context: MetricsContext) -> None:
 
     @staticmethod
     def name() -> str:
-        return "LambdaSink"
+        return "ConsoleSink"

setup.py

@@ -5,7 +5,7 @@
 
 setup(
     name="aws-embedded-metrics",
-    version="1.0.1b3",
+    version="1.0.1b4",
     author="Amazon Web Services",
     author_email="jarnance@amazon.com",
     description="AWS Embedded Metrics Package",

tests/environment/test_lambda_environment.py

@@ -1,6 +1,6 @@
 import os
 from aws_embedded_metrics.environment.lambda_environment import LambdaEnvironment
-from aws_embedded_metrics.sinks.lambda_sink import LambdaSink
+from aws_embedded_metrics.sinks.console_sink import ConsoleSink
 import pytest
 from faker import Faker
 
@@ -57,12 +57,12 @@ def test_get_log_group_name_returns_function_name():
     assert result == expected_name
 
 
-def test_create_sink_creates_LambdaSink():
+def test_create_sink_creates_ConsoleSink():
     # arrange
     env = LambdaEnvironment()
 
     # act
     result = env.get_sink()
 
     # assert
-    assert isinstance(result, LambdaSink)
+    assert isinstance(result, ConsoleSink)

tests/sinks/test_lambda_sink.py

@@ -1,10 +1,10 @@
-from aws_embedded_metrics.sinks.lambda_sink import LambdaSink
+from aws_embedded_metrics.sinks.console_sink import ConsoleSink
 from aws_embedded_metrics.logger.metrics_context import MetricsContext
 
 
 def test_accept_writes_to_stdout(capfd):
     # arrange
-    sink = LambdaSink()
+    sink = ConsoleSink()
     context = MetricsContext.empty()
     context.meta["Timestamp"] = 1