File upload multipart hits an error of ClassCastException fix #1815

Author: jknack

modules/jooby-netty/src/main/java/io/jooby/internal/netty/NettyContext.java

@@ -223,11 +223,7 @@ public NettyContext(ChannelHandlerContext ctx, HttpRequest req, Router router, S
   }
 
   @Nonnull @Override public Formdata form() {
-    if (form == null) {
-      form = Formdata.create(this);
-      decodeForm(req, form);
-    }
-    return form;
+    return multipart();
   }
 
   @Nonnull @Override public Multipart multipart() {

modules/jooby-utow/src/main/java/io/jooby/internal/utow/UtowContext.java

@@ -235,11 +235,7 @@ public UtowContext(HttpServerExchange exchange, Router router) {
   }
 
   @Nonnull @Override public Formdata form() {
-    if (form == null) {
-      form = Formdata.create(this);
-      formData(form, exchange.getAttachment(FORM_DATA));
-    }
-    return form;
+    return multipart();
   }
 
   @Nonnull @Override public Multipart multipart() {

tests/src/test/java/io/jooby/Issue1815.java

@@ -0,0 +1,41 @@
+package io.jooby;
+
+import io.jooby.junit.ServerTest;
+import io.jooby.junit.ServerTestRunner;
+import okhttp3.MediaType;
+import okhttp3.MultipartBody;
+
+import java.nio.file.Path;
+import java.nio.file.Paths;
+
+import static okhttp3.RequestBody.create;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class Issue1815 {
+
+  @ServerTest
+  public void shouldNotThrowClassCastExceptionOnFileUploadWithCsrfHandler(ServerTestRunner runner) {
+    runner.define(app -> {
+      app.before(new CsrfHandler());
+
+      app.post("/1815", ctx -> ctx.multipart("file"));
+    }).ready(http -> {
+      http.post("/1815", new MultipartBody.Builder()
+          .setType(MultipartBody.FORM)
+          .addFormDataPart("file", "fileupload.js",
+              create(userdir("src", "test", "resources", "files", "fileupload.js").toFile(),
+                  MediaType.parse("application/javascript")))
+          .build(), rsp -> {
+        assertEquals(StatusCode.FORBIDDEN_CODE, rsp.code());
+      });
+    });
+  }
+
+  private static Path userdir(String... segments) {
+    Path path = Paths.get(System.getProperty("user.dir"));
+    for (String segment : segments) {
+      path = path.resolve(segment);
+    }
+    return path;
+  }
+}