Make ProcessCredentialsProvider closeable, so that the internal credentials cache (which may be async and need to be closed) can be closed. I also verified that this is the only usage of CachedSupplier that is affected. (#2838)

Author: millems

.changes/next-release/bugfix-AWSSDKforJavav2-84c738e.json

@@ -0,0 +1,6 @@
+{
+    "category": "AWS SDK for Java v2", 
+    "contributor": "", 
+    "type": "bugfix", 
+    "description": "Make `ProcessCredentialsProvider` closeable, so that the internal credentials cache (which may be async and need to be closed) can be closed."
+}

core/auth/src/main/java/software/amazon/awssdk/auth/credentials/ProcessCredentialsProvider.java

@@ -29,6 +29,7 @@
 import software.amazon.awssdk.utils.DateUtils;
 import software.amazon.awssdk.utils.IoUtils;
 import software.amazon.awssdk.utils.Platform;
+import software.amazon.awssdk.utils.SdkAutoCloseable;
 import software.amazon.awssdk.utils.Validate;
 import software.amazon.awssdk.utils.cache.CachedSupplier;
 import software.amazon.awssdk.utils.cache.NonBlocking;
@@ -53,7 +54,7 @@
  * </ul>
  */
 @SdkPublicApi
-public final class ProcessCredentialsProvider implements AwsCredentialsProvider {
+public final class ProcessCredentialsProvider implements AwsCredentialsProvider, SdkAutoCloseable {
     private static final JsonNodeParser PARSER = JsonNodeParser.builder()
                                                                .removeErrorLocations(true)
                                                                .build();
@@ -204,6 +205,11 @@ private String executeCommand() throws IOException, InterruptedException {
         }
     }
 
+    @Override
+    public void close() {
+        processCredentialCache.close();
+    }
+
     /**
      * Used to configure and create a {@link ProcessCredentialsProvider}. See {@link #builder()} creation.
      */

core/auth/src/test/java/software/amazon/awssdk/auth/credentials/ProcessCredentialsProviderTest.java

@@ -164,6 +164,16 @@ public void processOutputLimitDefaultPassesLargeInput() {
         Assertions.assertThat(sessionCredentials.accessKeyId()).isEqualTo("accessKeyId");
         Assertions.assertThat(sessionCredentials.sessionToken()).isNotNull();
     }
+    
+    @Test
+    public void closeDoesNotRaise() {
+        ProcessCredentialsProvider credentialsProvider =
+            ProcessCredentialsProvider.builder()
+                                      .command(scriptLocation + " accessKeyId secretAccessKey sessionToken")
+                                      .build();
+        credentialsProvider.resolveCredentials();
+        credentialsProvider.close();
+    }
 
     public static String copyProcessCredentialsScript() {
         String scriptClasspathFilename = Platform.isWindows() ? "windows-credentials-script.bat"