[Localstack] Get region from env variables or default (#3556)

Co-authored-by: Pozueco Adrian <[email protected]>
Co-authored-by: Eddú Meléndez Gonzales <[email protected]>

Author: adrianpozueco

modules/localstack/src/main/java/org/testcontainers/containers/localstack/LocalStackContainer.java

@@ -45,6 +45,8 @@ public class LocalStackContainer extends GenericContainer<LocalStackContainer> {
 
     private static final String DEFAULT_TAG = "0.11.2";
 
+    private static final String DEFAULT_REGION = "us-east-1";
+
     @Deprecated
     public static final String VERSION = DEFAULT_TAG;
 
@@ -311,7 +313,7 @@ public String getSecretKey() {
      * @return a default region
      */
     public String getRegion() {
-        return "us-east-1";
+        return this.getEnvMap().getOrDefault("DEFAULT_REGION", DEFAULT_REGION);
     }
 
     public interface EnabledService {

modules/localstack/src/test/java/org/testcontainers/containers/localstack/LocalstackContainerTest.java

@@ -1,5 +1,6 @@
 package org.testcontainers.containers.localstack;
 
+import com.amazonaws.client.builder.AwsClientBuilder;
 import com.amazonaws.services.kms.AWSKMS;
 import com.amazonaws.services.kms.AWSKMSClientBuilder;
 import com.amazonaws.services.kms.model.CreateKeyRequest;
@@ -286,4 +287,29 @@ private String runAwsCliAgainstDockerNetworkContainer(String command) throws Exc
             return logs;
         }
     }
+
+    public static class WithRegion {
+
+        // with_region {
+        private static String region = "eu-west-1";
+
+        @ClassRule
+        public static LocalStackContainer localstack = new LocalStackContainer(LocalstackTestImages.LOCALSTACK_IMAGE)
+            .withEnv("DEFAULT_REGION", region)
+            .withServices(Service.S3);
+
+        // }
+
+        @Test
+        public void s3EndpointHasProperRegion() {
+            final AwsClientBuilder.EndpointConfiguration endpointConfiguration = localstack.getEndpointConfiguration(
+                Service.S3
+            );
+            assertEquals(
+                "The endpoint configuration has right region",
+                region,
+                endpointConfiguration.getSigningRegion()
+            );
+        }
+    }
 }