Upload a file to a server (for example, Imgur) and report progress as the request body is being written. You can implement a ProgressListener to receive updates and wrap the original request body with ProgressRequestBody. This allows you to monitor how many bytes have been uploaded and calculate the percentage of completion.

=== ":material-language-kotlin: Kotlin"
    ```kotlin
      class UploadProgress {

        companion object {

import org.lastaflute.web.servlet.request.RequestManager;
import org.lastaflute.web.util.LaServletContextUtil;
import org.lastaflute.web.validation.ActionValidator;
import org.opensearch.monitor.os.OsProbe;

import com.google.common.cache.CacheBuilder;
import com.google.common.cache.CacheLoader;
import com.google.common.cache.LoadingCache;
import com.ibm.icu.util.ULocale;