Fixes #4542 - Add ability to override upload location

extension/fileupload/src/main/java/cloud/piranha/extension/fileupload/FileUploadMultiPartInitializer.java

@@ -44,8 +44,10 @@
  * </p>
  *
  * <ol>
- * <li>Sets the MultiPartManager to an instance of FileUploadMultiPartManager.</li>
- * <li>Adds the JakartaFileCleaner listener that cleans up the temporary files.</li>
+ * <li>Sets the MultiPartManager to an instance of
+ * FileUploadMultiPartManager.</li>
+ * <li>Adds the JakartaFileCleaner listener that cleans up the temporary
+ * files.</li>
  * </ol>
  *
  * @author Manfred Riem (mriem@manorrock.com)
@@ -62,13 +64,17 @@ public class FileUploadMultiPartInitializer implements ServletContainerInitializ
      */
     public FileUploadMultiPartInitializer() {
     }
-    
+
     @Override
     public void onStartup(Set<Class<?>> classes, ServletContext servletContext) throws ServletException {
         WebApplication webApplication = (WebApplication) servletContext;
-        LOGGER.log(TRACE, "Setting the MultiPartManager");
+        if (LOGGER.isLoggable(TRACE)) {
+            LOGGER.log(TRACE, "Setting the MultiPartManager");
+        }
         webApplication.getManager().setMultiPartManager(new FileUploadMultiPartManager());
-        LOGGER.log(TRACE, "Adding the listener used to cleanup temporary files");
+        if (LOGGER.isLoggable(TRACE)) {
+            LOGGER.log(TRACE, "Adding the listener used to cleanup temporary files");
+        }
         webApplication.addListener("org.apache.commons.fileupload2.jakarta.servlet6.JakartaFileCleaner");
     }
 }

extension/fileupload/src/main/java/cloud/piranha/extension/fileupload/FileUploadMultiPartManager.java

@@ -65,6 +65,12 @@ public class FileUploadMultiPartManager implements MultiPartManager {
     private static final String FILE_SIZE_THRESHOLD_NAME
             = "cloud.piranha.extension.fileupload.fileSizeTreshold";
 
+    /**
+     * Stores the constant for the output directory.
+     */
+    private static final String OUTPUT_DIRECTORY_NAME
+            = "cloud.piranha.extension.fileupload.outputDirectory";
+
     /**
      * Stores the logger.
      */
@@ -142,27 +148,47 @@ public Part getPart(WebApplication webApplication, WebApplicationRequest request
     private synchronized JakartaServletFileUpload setupFileUpload(WebApplication webApplication, MultipartConfigElement multipartConfig) {
         JakartaServletFileUpload upload = (JakartaServletFileUpload) webApplication.getAttribute(FileUploadMultiPartManager.class.getName());
         if (upload == null) {
-            File outputDirectory;
-            if (multipartConfig.getLocation() == null || multipartConfig.getLocation().isEmpty()) {
-                outputDirectory = (File) webApplication.getAttribute(TEMPDIR);
-            } else {
+            /*
+             * Default to TEMPDIR.
+             */
+            File outputDirectory = (File) webApplication.getAttribute(TEMPDIR);
+            /*
+             * If the multipart config has a location use it. If it is relative
+             * use the TEMPDIR as the parent directory.
+             */
+            if (multipartConfig.getLocation() != null && !multipartConfig.getLocation().isEmpty()) {
                 File location = new File(multipartConfig.getLocation());
                 if (!location.isAbsolute()) {
                     location = ((File) webApplication.getAttribute(TEMPDIR)).toPath().resolve(location.toPath()).toFile();
                 }
                 outputDirectory = location;
             }
+            /*
+             * If OUTPUT_DIRECTORY_NAME is set use it.
+             */
+            if (webApplication.getInitParameter(OUTPUT_DIRECTORY_NAME) != null) {
+                outputDirectory = new File(webApplication.getInitParameter(OUTPUT_DIRECTORY_NAME));
+            }
+            /*
+             * Default to 10240 (10 KB).
+             */
             int sizeThreshold = 10240;
+            /*
+             * If the multipart config has a size > 0 use it.
+             */
+            if (multipartConfig.getFileSizeThreshold() != 0) {
+                sizeThreshold = multipartConfig.getFileSizeThreshold();
+            }
+            /*
+             * If FILE_SIZE_THRESHOLD_NAME is set use it.
+             */
             if (webApplication.getInitParameter(FILE_SIZE_THRESHOLD_NAME) != null) {
                 try {
                     sizeThreshold = Integer.parseInt(webApplication.getInitParameter("cloud.piranha.extension.fileupload.fileSizeTreshold"));
                 } catch (NumberFormatException nfe) {
                     // ignore and let defaults apply.
                 }
             }
-            if (multipartConfig.getFileSizeThreshold() != 0) {
-                sizeThreshold = multipartConfig.getFileSizeThreshold();
-            }
             DiskFileItemFactory factory = DiskFileItemFactory
                     .builder()
                     .setBufferSize(sizeThreshold)

extension/fileupload/src/site/markdown/index.md

@@ -6,3 +6,26 @@ file upload. This extension is available by default for the following runtimes:
 1. Piranha Server
 1. Piranha Servlet
 1. Piranha Web Profile
+
+## Configuration parameters
+
+The following configuration parameters are available:
+
+1. `cloud.piranha.extension.fileupload.outputDirectory` - the directory where
+   the file upload will store temporary files. The default is the same location
+   as the ServletContext TEMPDIR.
+
+1. `cloud.piranha.extension.fileupload.fileSizeTreshold` - the file size
+   threshold (in bytes) before the runtime will create a temporary file on the
+   filesystem to store the upload. The default is 10240 (10 KB).
+
+## Setting the configuration parameters using web.xml
+
+You can set the configuration parameter in the web.xml as illustrated below:
+
+```xml
+    <context-param>
+        <param-name>cloud.piranha.extension.fileupload.fileSizeTreshold</param-name>
+        <param-value>1048576</param-value>
+    </context-param>
+```