[TOMCAT-69690] allow to plug in ProgressListener while processing multipart requests

Author: reiern70

java/org/apache/catalina/connector/LocalStrings.properties

@@ -97,4 +97,4 @@ requestFacade.nullRequest=The request object has been recycled and is no longer
 response.illegalWrap=The response wrapper must wrap the response obtained from getResponse()
 response.sendRedirectFail=Failed to redirect to [{0}]
 
-responseFacade.nullResponse=The response object has been recycled and is no longer associated with this facade
+responseFacade.nullResponse=The response object has been recycled and is no longer associated with this facade

java/org/apache/catalina/connector/Request.java

@@ -76,6 +76,7 @@
 import org.apache.catalina.Session;
 import org.apache.catalina.TomcatPrincipal;
 import org.apache.catalina.Wrapper;
+import org.apache.catalina.core.ApplicationContextFacade;
 import org.apache.catalina.core.ApplicationFilterChain;
 import org.apache.catalina.core.ApplicationMapping;
 import org.apache.catalina.core.ApplicationPart;
@@ -2486,7 +2487,12 @@ private void parseParts() {
         }
         factory.setSizeThreshold(mce.getFileSizeThreshold());
 
+        ServletContext servletContext = getServletContext();
         FileUpload upload = new FileUpload();
+        // allow applications to register custom progress listeners
+        if (servletContext instanceof ApplicationContextFacade applicationContext) {
+            upload.setProgressListener(applicationContext.getProgressListenerFactory().newProgressListener());
+        }
         upload.setFileItemFactory(factory);
         upload.setFileSizeMax(mce.getMaxFileSize());
         upload.setSizeMax(mce.getMaxRequestSize());
@@ -2545,7 +2551,6 @@ private void parseParts() {
         }
     }
 
-
     @Override
     public Part getPart(String name) throws IOException, IllegalStateException, ServletException {
         for (Part part : getParts()) {

java/org/apache/catalina/core/ApplicationContext.java

@@ -17,6 +17,7 @@
 package org.apache.catalina.core;
 
 import java.io.InputStream;
+import java.lang.reflect.Constructor;
 import java.lang.reflect.InvocationTargetException;
 import java.net.MalformedURLException;
 import java.net.URL;
@@ -67,16 +68,20 @@
 import org.apache.catalina.WebResourceRoot;
 import org.apache.catalina.Wrapper;
 import org.apache.catalina.connector.Connector;
+import org.apache.catalina.connector.Request;
 import org.apache.catalina.mapper.MappingData;
 import org.apache.catalina.util.Introspection;
 import org.apache.catalina.util.ServerInfo;
 import org.apache.catalina.util.URLEncoder;
+import org.apache.juli.logging.Log;
+import org.apache.juli.logging.LogFactory;
 import org.apache.tomcat.util.ExceptionUtils;
 import org.apache.tomcat.util.buf.CharChunk;
 import org.apache.tomcat.util.buf.MessageBytes;
 import org.apache.tomcat.util.buf.UDecoder;
 import org.apache.tomcat.util.descriptor.web.FilterDef;
 import org.apache.tomcat.util.http.RequestUtil;
+import org.apache.tomcat.util.http.fileupload.ProgressListenerFactory;
 import org.apache.tomcat.util.res.StringManager;
 
 
@@ -89,6 +94,8 @@
  */
 public class ApplicationContext implements ServletContext {
 
+    private static final Log log = LogFactory.getLog(Request.class);
+
     // ----------------------------------------------------------- Constructors
 
     /**
@@ -146,6 +153,11 @@ public ApplicationContext(StandardContext context) {
     private final Map<String,String> parameters = new ConcurrentHashMap<>();
 
 
+    /**
+     * The ProgressListenerFactory used to create {@link org.apache.tomcat.util.http.fileupload.ProgressListener}
+     */
+    private ProgressListenerFactory progressListenerFactory;
+
     /**
      * The string manager for this package.
      */
@@ -1161,6 +1173,30 @@ protected StandardContext getContext() {
         return this.context;
     }
 
+    public ProgressListenerFactory getProgressListenerFactory() {
+        if (progressListenerFactory == null) {
+            progressListenerFactory = newProgressListenerFactory();
+        }
+        return progressListenerFactory;
+    }
+
+    private ProgressListenerFactory newProgressListenerFactory() {
+        String progressListenerFactoryClassName = getInitParameter(ProgressListenerFactory.FACTORY_NAME);
+        if (progressListenerFactoryClassName == null || progressListenerFactoryClassName.isEmpty()) {
+            log.warn(sm.getString("applicationContext.no.upload.progressListenerFactory", progressListenerFactoryClassName));
+            return ProgressListenerFactory.NULL_FACTORY;
+        }
+        try {
+            Class<?> progressListenerFactoryClass = Introspection.loadClass(context, progressListenerFactoryClassName);
+            Constructor<?> ctor = progressListenerFactoryClass.getConstructor();
+            return (ProgressListenerFactory) ctor.newInstance();
+        } catch (InvocationTargetException | NoSuchMethodException | InstantiationException
+                 | ClassCastException | IllegalAccessException e) {
+            log.error(sm.getString("applicationContext.invalid.progressListenerFactory", progressListenerFactoryClassName), e);
+            return ProgressListenerFactory.NULL_FACTORY;
+        }
+    }
+
     /**
      * Clear all application-created attributes.
      */

java/org/apache/catalina/core/ApplicationContextFacade.java

@@ -37,6 +37,8 @@
 import jakarta.servlet.SessionTrackingMode;
 import jakarta.servlet.descriptor.JspConfigDescriptor;
 
+import org.apache.tomcat.util.http.fileupload.ProgressListenerFactory;
+
 
 /**
  * Facade object which masks the internal <code>ApplicationContext</code> object from the web application.
@@ -359,6 +361,9 @@ public Map<String,? extends ServletRegistration> getServletRegistrations() {
         return context.getServletRegistrations();
     }
 
+    public ProgressListenerFactory getProgressListenerFactory() {
+        return context.getProgressListenerFactory();
+    }
 
     @Override
     public String getVirtualServerName() {

java/org/apache/catalina/core/LocalStrings.properties

@@ -40,6 +40,8 @@ applicationContext.setSessionTimeout.ise=The session timeout cannot be set for c
 applicationContext.setSessionTracking.iae.invalid=The session tracking mode [{0}] requested for context [{1}] is not supported by that context
 applicationContext.setSessionTracking.iae.ssl=The session tracking modes requested for context [{0}] included SSL and at least one other mode. SSL may not be configured with other modes.
 applicationContext.setSessionTracking.ise=The session tracking modes for context [{0}] cannot be set whilst the context is running
+applicationContext.no.upload.progressListenerFactory = No factory class for upload progress reporting specified
+applicationContext.invalid.progressListenerFactory = Specified class [{0}] is not a valid ProgressListenerFactory
 
 applicationDispatcher.allocateException=Allocate exception for servlet [{0}]
 applicationDispatcher.customResponse=The response class [{0}] could not be unwraped to the Catalina response class and will be closed immediately after the forward

java/org/apache/tomcat/util/http/fileupload/FileUploadBase.java

@@ -272,6 +272,7 @@ public List<FileItem> parseRequest(final RequestContext ctx)
             throws FileUploadException {
         final List<FileItem> items = new ArrayList<>();
         boolean successful = false;
+        notifyUploadStarted();
         try {
             final FileItemIterator iter = getItemIterator(ctx);
             final FileItemFactory fileItemFactory = Objects.requireNonNull(getFileItemFactory(),
@@ -315,6 +316,19 @@ public List<FileItem> parseRequest(final RequestContext ctx)
                     }
                 }
             }
+            notifyUploadFinished();
+        }
+    }
+
+    private void notifyUploadStarted() {
+        if (listener != null) {
+            listener.uploadStarted();
+        }
+    }
+
+    private void notifyUploadFinished() {
+        if (listener != null) {
+            listener.uploadFinished();
         }
     }
 

java/org/apache/tomcat/util/http/fileupload/ProgressListener.java

@@ -23,7 +23,12 @@
 public interface ProgressListener {
 
     /**
-     * Updates the listeners status information.
+     * Notify that processing the file upload has started.
+     */
+    void uploadStarted();
+
+    /**
+     * Updates the listener's status information.
      *
      * @param pBytesRead The total number of bytes, which have been read
      *   so far.
@@ -34,4 +39,8 @@ public interface ProgressListener {
      */
     void update(long pBytesRead, long pContentLength, int pItems);
 
+    /**
+     * Notify that processing the file upload has finished.
+     */
+    void uploadFinished();
 }

java/org/apache/tomcat/util/http/fileupload/ProgressListenerFactory.java

@@ -0,0 +1,46 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.tomcat.util.http.fileupload;
+
+/**
+ * Factory for {@link ProgressListener}. Users can specify this via a System property. See FACTORY_NAME
+ */
+public interface ProgressListenerFactory {
+
+    /**
+     * Constant for the servlet init parameter that can be used to specify a factory for ProgressListeners
+     */
+    String FACTORY_NAME = "tomcat.fileUploadProgressListenerFactory";
+
+    /**
+     * Factory that creates no listeners. To avoid null checks in code.
+     */
+    ProgressListenerFactory NULL_FACTORY = new ProgressListenerFactory() {
+        @Override
+        public ProgressListener newProgressListener() {
+            return null;
+        }
+    };
+
+
+    /**
+     * @return returns a new {@link ProgressListener} for current request.
+     */
+    ProgressListener newProgressListener();
+
+}