fix: powertools specific log level env var to not conflict with the system LOG_LEVEL (#306)

Co-authored-by: Pankaj Agrawal <pankaagr@amazon.com>

Author: pankajagrawal16

docs/content/core/logging.mdx

@@ -37,7 +37,7 @@ Powertools extends the functionality of Log4J. Below is an example log4j2.xml fi
 </Configuration>
 ```
 
-You can also override log level by setting `LOG_LEVEL` env var  - Here is an example using AWS Serverless Application Model (SAM)
+You can also override log level by setting `POWERTOOLS_LOG_LEVEL` env var  - Here is an example using AWS Serverless Application Model (SAM)
 
 ```yaml:title=template.yaml
 Resources:
@@ -48,7 +48,7 @@ Resources:
         Runtime: java8
         Environment:
             Variables:
-                LOG_LEVEL: DEBUG # highlight-line
+                POWERTOOLS_LOG_LEVEL: DEBUG # highlight-line
 ```
 
 You can also explicitly set a service name via `POWERTOOLS_SERVICE_NAME` env var. This sets **service** key that will be present across all log statements.

docs/content/index.mdx

@@ -123,7 +123,7 @@ Environment variable | Description | Utility
 **POWERTOOLS_SERVICE_NAME** | Sets service name used for tracing namespace, metrics dimension and structured logging | All
 **POWERTOOLS_METRICS_NAMESPACE** | Sets namespace used for metrics | [Metrics](./core/metrics)
 **POWERTOOLS_LOGGER_SAMPLE_RATE** | Debug log sampling | [Logging](./core/logging)
-**LOG_LEVEL** | Sets logging level | [Logging](./core/logging)
+**POWERTOOLS_LOG_LEVEL** | Sets logging level | [Logging](./core/logging)
 **POWERTOOLS_TRACER_CAPTURE_RESPONSE** | Enables/Disables tracing mode to capture method response | [Tracing](./core/tracing)
 **POWERTOOLS_TRACER_CAPTURE_ERROR** | Enables/Disables tracing mode to capture method error | [Tracing](./core/tracing)
 

example/template.yaml

@@ -21,7 +21,7 @@ Resources:
       Environment: # More info about Env Vars: https://github.com/awslabs/serverless-application-model/blob/master/versions/2016-10-31.md#environment-object
         Variables:
           POWERTOOLS_SERVICE_NAME: "Payment Service"
-          LOG_LEVEL: INFO
+          POWERTOOLS_LOG_LEVEL: INFO
       Tracing: Active
       Events:
         HelloWorld:

powertools-logging/src/main/java/software/amazon/lambda/powertools/logging/internal/LambdaLoggingAspect.java

@@ -56,7 +56,7 @@ public final class LambdaLoggingAspect {
     private static final Logger LOG = LogManager.getLogger(LambdaLoggingAspect.class);
     private static final Random SAMPLER = new Random();
 
-    private static final String LOG_LEVEL = System.getenv("LOG_LEVEL");
+    private static final String LOG_LEVEL = System.getenv("POWERTOOLS_LOG_LEVEL");
     private static final String SAMPLING_RATE = System.getenv("POWERTOOLS_LOGGER_SAMPLE_RATE");
 
     private static Level LEVEL_AT_INITIALISATION;