diff --git a/asterixdb/asterix-cloud/src/main/java/org/apache/asterix/cloud/clients/aws/s3/S3BufferedWriter.java b/asterixdb/asterix-cloud/src/main/java/org/apache/asterix/cloud/clients/aws/s3/S3BufferedWriter.java
index 9104d9a..6c02bbc 100644
--- a/asterixdb/asterix-cloud/src/main/java/org/apache/asterix/cloud/clients/aws/s3/S3BufferedWriter.java
+++ b/asterixdb/asterix-cloud/src/main/java/org/apache/asterix/cloud/clients/aws/s3/S3BufferedWriter.java
@@ -69,6 +69,9 @@
 
     @Override
     public void finish() throws HyracksDataException {
+        if (uploadId == null) {
+            return;
+        }
         CompletedMultipartUpload completedMultipartUpload = CompletedMultipartUpload.builder().parts(partQueue).build();
         CompleteMultipartUploadRequest completeMultipartUploadRequest = CompleteMultipartUploadRequest.builder()
                 .bucket(bucket).key(path).uploadId(uploadId).multipartUpload(completedMultipartUpload).build();
@@ -97,6 +100,9 @@
 
     @Override
     public void abort() throws HyracksDataException {
+        if (uploadId == null) {
+            return;
+        }
         s3Client.abortMultipartUpload(
                 AbortMultipartUploadRequest.builder().bucket(bucket).key(path).uploadId(uploadId).build());
     }
diff --git a/asterixdb/asterix-cloud/src/main/java/org/apache/asterix/cloud/clients/aws/s3/S3ClientConfig.java b/asterixdb/asterix-cloud/src/main/java/org/apache/asterix/cloud/clients/aws/s3/S3ClientConfig.java
index 281fe77..bbe8586 100644
--- a/asterixdb/asterix-cloud/src/main/java/org/apache/asterix/cloud/clients/aws/s3/S3ClientConfig.java
+++ b/asterixdb/asterix-cloud/src/main/java/org/apache/asterix/cloud/clients/aws/s3/S3ClientConfig.java
@@ -55,7 +55,16 @@
         return prefix;
     }
 
+    public boolean isEncodeKeys() {
+        // to workaround https://github.com/findify/s3mock/issues/187 in our S3Mock, we encode/decode keys
+        return isS3Mock();
+    }
+
     public AwsCredentialsProvider createCredentialsProvider() {
         return anonymousAuth ? AnonymousCredentialsProvider.create() : DefaultCredentialsProvider.create();
     }
+
+    private boolean isS3Mock() {
+        return endpoint != null && !endpoint.isEmpty();
+    }
 }
diff --git a/asterixdb/asterix-cloud/src/main/java/org/apache/asterix/cloud/clients/aws/s3/S3CloudClient.java b/asterixdb/asterix-cloud/src/main/java/org/apache/asterix/cloud/clients/aws/s3/S3CloudClient.java
index 6d65f69..0fb9c08 100644
--- a/asterixdb/asterix-cloud/src/main/java/org/apache/asterix/cloud/clients/aws/s3/S3CloudClient.java
+++ b/asterixdb/asterix-cloud/src/main/java/org/apache/asterix/cloud/clients/aws/s3/S3CloudClient.java
@@ -18,6 +18,7 @@
  */
 package org.apache.asterix.cloud.clients.aws.s3;
 
+import static org.apache.asterix.cloud.clients.aws.s3.S3Utils.encodeURI;
 import static org.apache.asterix.cloud.clients.aws.s3.S3Utils.listS3Objects;
 
 import java.io.File;
@@ -108,6 +109,7 @@
 
     @Override
     public Set<String> listObjects(String bucket, String path, FilenameFilter filter) {
+        path = config.isEncodeKeys() ? encodeURI(path) : path;
         return filterAndGet(listS3Objects(s3Client, bucket, path), filter);
     }
 
@@ -171,6 +173,7 @@
 
     @Override
     public void copy(String bucket, String srcPath, FileReference destPath) {
+        srcPath = config.isEncodeKeys() ? encodeURI(srcPath) : srcPath;
         List<S3Object> objects = listS3Objects(s3Client, bucket, srcPath);
         for (S3Object object : objects) {
             String srcKey = object.key();
@@ -223,7 +226,7 @@
     private Set<String> filterAndGet(List<S3Object> contents, FilenameFilter filter) {
         Set<String> files = new HashSet<>();
         for (S3Object s3Object : contents) {
-            String path = S3Utils.decodeURI(s3Object.key());
+            String path = config.isEncodeKeys() ? S3Utils.decodeURI(s3Object.key()) : s3Object.key();
             if (filter.accept(null, IoUtil.getFileNameFromPath(path))) {
                 files.add(path);
             }
diff --git a/asterixdb/asterix-cloud/src/main/java/org/apache/asterix/cloud/clients/aws/s3/S3Utils.java b/asterixdb/asterix-cloud/src/main/java/org/apache/asterix/cloud/clients/aws/s3/S3Utils.java
index 4ea11b2..2faba79 100644
--- a/asterixdb/asterix-cloud/src/main/java/org/apache/asterix/cloud/clients/aws/s3/S3Utils.java
+++ b/asterixdb/asterix-cloud/src/main/java/org/apache/asterix/cloud/clients/aws/s3/S3Utils.java
@@ -40,7 +40,7 @@
         String newMarker = null;
         ListObjectsV2Response listObjectsResponse;
         ListObjectsV2Request.Builder listObjectsBuilder = ListObjectsV2Request.builder().bucket(bucket);
-        listObjectsBuilder.prefix(encodeURI(toCloudPrefix(path)));
+        listObjectsBuilder.prefix(toCloudPrefix(path));
         while (true) {
             // List the objects from the start, or from the last marker in case of truncated result
             if (newMarker == null) {