1 files changed, 83 insertions, 0 deletions
diff --git a/src/main/java/org/traccar/web/ResponseWrapper.java b/src/main/java/org/traccar/web/ResponseWrapper.java
new file mode 100644
index 000000000..a0eaf6788
--- /dev/null
+++ b/src/main/java/org/traccar/web/ResponseWrapper.java
@@ -0,0 +1,83 @@
+/*
+ * Copyright 2023 Anton Tananaev (anton@traccar.org)
+ *
+ * Licensed 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.traccar.web;
+
+import jakarta.servlet.ServletOutputStream;
+import jakarta.servlet.WriteListener;
+import jakarta.servlet.http.HttpServletResponse;
+import jakarta.servlet.http.HttpServletResponseWrapper;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+
+public class ResponseWrapper extends HttpServletResponseWrapper {
+
+    private final ByteArrayOutputStream capture;
+    private ServletOutputStream output;
+
+    public ResponseWrapper(HttpServletResponse response) {
+        super(response);
+        capture = new ByteArrayOutputStream(response.getBufferSize());
+    }
+
+    @Override
+    public ServletOutputStream getOutputStream() {
+        if (output == null) {
+            output = new ServletOutputStream() {
+                @Override
+                public boolean isReady() {
+                    return true;
+                }
+
+                @Override
+                public void setWriteListener(WriteListener writeListener) {
+                }
+
+                @Override
+                public void write(int b) {
+                    capture.write(b);
+                }
+
+                @Override
+                public void flush() throws IOException {
+                    capture.flush();
+                }
+
+                @Override
+                public void close() throws IOException {
+                    capture.close();
+                }
+            };
+        }
+        return output;
+    }
+
+    @Override
+    public void flushBuffer() throws IOException {
+        super.flushBuffer();
+        if (output != null) {
+            output.flush();
+        }
+    }
+
+    public byte[] getCapture() throws IOException {
+        if (output != null) {
+            output.close();
+            return capture.toByteArray();
+        }
+        return null;
+    }
+
+}