fix: cold start only on on-demand invocation

pom.xml

@@ -501,6 +501,11 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-surefire-plugin</artifactId>
+                <configuration>
+                    <environmentVariables>
+                        <AWS_LAMBDA_INITIALIZATION_TYPE>on-demand</AWS_LAMBDA_INITIALIZATION_TYPE>
+                    </environmentVariables>
+                </configuration>
             </plugin>
             <plugin>
                 <groupId>org.jacoco</groupId>
@@ -632,6 +637,9 @@
                                 --add-opens java.base/java.util=ALL-UNNAMED
                                 --add-opens java.base/java.lang=ALL-UNNAMED
                             </argLine>
+                            <environmentVariables>
+                                <AWS_LAMBDA_INITIALIZATION_TYPE>on-demand</AWS_LAMBDA_INITIALIZATION_TYPE>
+                            </environmentVariables>
                         </configuration>
                     </plugin>
                 </plugins>

powertools-common/src/main/java/software/amazon/lambda/powertools/common/internal/LambdaConstants.java

@@ -28,4 +28,6 @@ private LambdaConstants() {
     public static final String ROOT_EQUALS = "Root=";
     public static final String POWERTOOLS_SERVICE_NAME = "POWERTOOLS_SERVICE_NAME";
     public static final String SERVICE_UNDEFINED = "service_undefined";
+    public static final String AWS_LAMBDA_INITIALIZATION_TYPE = "AWS_LAMBDA_INITIALIZATION_TYPE";
+    public static final String ON_DEMAND_INVOCATION_TYPE = "on-demand";
 }

powertools-common/src/main/java/software/amazon/lambda/powertools/common/internal/LambdaHandlerProcessor.java

@@ -93,7 +93,14 @@ protected static void resetServiceName() {
     }
 
     public static boolean isColdStart() {
-        return isColdStart == null;
+        if (isColdStart != null) {
+            return isColdStart;
+        }
+
+        String initType = System.getenv(LambdaConstants.AWS_LAMBDA_INITIALIZATION_TYPE);
+        isColdStart = LambdaConstants.ON_DEMAND_INVOCATION_TYPE.equals(initType);
+
+        return isColdStart;
     }
 
     public static void coldStartDone() {

powertools-common/src/test/java/software/amazon/lambda/powertools/common/internal/LambdaHandlerProcessorTest.java

@@ -216,6 +216,7 @@ void extractContext_notKnownHandler() {
     }
 
     @Test
+    @SetEnvironmentVariable(key = LambdaConstants.AWS_LAMBDA_INITIALIZATION_TYPE, value = LambdaConstants.ON_DEMAND_INVOCATION_TYPE)
     void isColdStart() {
         boolean isColdStart = LambdaHandlerProcessor.isColdStart();
 

powertools-idempotency/powertools-idempotency-dynamodb/pom.xml

@@ -104,7 +104,6 @@
             <scope>test</scope>
         </dependency>
     </dependencies>
-
     <profiles>
         <profile>
             <id>generate-graalvm-files</id>

powertools-logging/powertools-logging-log4j/pom.xml

@@ -120,6 +120,9 @@
                                 --add-opens java.base/java.util=ALL-UNNAMED
                                 --add-opens java.base/java.lang=ALL-UNNAMED
                             </argLine>
+                            <environmentVariables>
+                                <AWS_LAMBDA_INITIALIZATION_TYPE>on-demand</AWS_LAMBDA_INITIALIZATION_TYPE>
+                            </environmentVariables>
                         </configuration>
                     </plugin>
                 </plugins>

powertools-logging/powertools-logging-log4j/src/test/java/org/apache/logging/log4j/layout/template/json/resolver/PowerToolsResolverFactoryTest.java

@@ -79,7 +79,7 @@ void shouldLogInJsonFormat() {
         File logFile = new File("target/logfile.json");
         assertThat(contentOf(logFile)).contains(
                 "{\"level\":\"DEBUG\",\"message\":\"Test debug event\",\"cold_start\":true,\"function_arn\":\"arn:aws:lambda:us-east-1:123456789012:function:test\",\"function_memory_size\":128,\"function_name\":\"test-function\",\"function_request_id\":\"test-request-id\",\"function_version\":\"1\",\"service\":\"testLog4j\",\"timestamp\":")
-                .contains("\"xray_trace_id\":\"1-63441c4a-abcdef012345678912345678\",\"myKey\":\"myValue\"}\n");
+                .contains("\"xray_trace_id\":\"1-63441c4a-abcdef012345678912345678\",\"myKey\":\"myValue\"}\r\n");
     }
 
     @Test
@@ -89,7 +89,7 @@ void shouldLogInEcsFormat() {
 
         File logFile = new File("target/ecslogfile.json");
         assertThat(contentOf(logFile)).contains(
-                "\"ecs.version\":\"1.2.0\",\"log.level\":\"DEBUG\",\"message\":\"Test debug event\",\"service.name\":\"testLog4j\",\"service.version\":\"1\",\"log.logger\":\"software.amazon.lambda.powertools.logging.internal.handler.PowertoolsLogEnabled\",\"process.thread.name\":\"main\",\"cloud.provider\":\"aws\",\"cloud.service.name\":\"lambda\",\"cloud.region\":\"eu-central-1\",\"cloud.account.id\":\"123456789012\",\"faas.id\":\"arn:aws:lambda:us-east-1:123456789012:function:test\",\"faas.name\":\"test-function\",\"faas.version\":\"1\",\"faas.memory\":128,\"faas.execution\":\"test-request-id\",\"faas.coldstart\":true,\"trace.id\":\"1-63441c4a-abcdef012345678912345678\",\"myKey\":\"myValue\"}\n");
+                "\"ecs.version\":\"1.2.0\",\"log.level\":\"DEBUG\",\"message\":\"Test debug event\",\"service.name\":\"testLog4j\",\"service.version\":\"1\",\"log.logger\":\"software.amazon.lambda.powertools.logging.internal.handler.PowertoolsLogEnabled\",\"process.thread.name\":\"main\",\"cloud.provider\":\"aws\",\"cloud.service.name\":\"lambda\",\"cloud.region\":\"eu-central-1\",\"cloud.account.id\":\"123456789012\",\"faas.id\":\"arn:aws:lambda:us-east-1:123456789012:function:test\",\"faas.name\":\"test-function\",\"faas.version\":\"1\",\"faas.memory\":128,\"faas.execution\":\"test-request-id\",\"faas.coldstart\":true,\"trace.id\":\"1-63441c4a-abcdef012345678912345678\",\"myKey\":\"myValue\"}\r\n");
     }
 
 }

powertools-logging/powertools-logging-logback/src/test/java/software/amazon/lambda/powertools/logging/internal/LambdaEcsEncoderTest.java

@@ -163,7 +163,7 @@ void shouldLogException() {
 
         // THEN (stack is logged with root cause first)
         assertThat(result).contains(
-                "\"message\":\"Error\",\"error.message\":\"Unexpected value\",\"error.type\":\"java.lang.IllegalStateException\",\"error.stack_trace\":\"java.lang.IllegalStateException: Unexpected value\\n");
+                "\"message\":\"Error\",\"error.message\":\"Unexpected value\",\"error.type\":\"java.lang.IllegalStateException\",\"error.stack_trace\":\"java.lang.IllegalStateException: Unexpected value\\r\\n");
     }
 
     private void setMDC() {