Umbraco Forms: Fix Endless Submit Loop After Reinitialization

Experiencing an endless submit loop in Umbraco Forms after reinitialization? You're not alone! This article dives deep into a specific issue encountered in Umbraco Forms versions 16.2.0 and Umbraco 16.3.4, where reinitializing forms on pages with multiple forms triggers a frustrating continuous submit loop. We'll explore the problem, understand the steps to reproduce it, and discuss the expected versus actual results. Let's get started on resolving this critical Umbraco Forms issue.

Understanding the Umbraco Forms Reinitialization Issue

The umbracoFormsReinitialize feature, introduced to address issue #1224, aimed to provide a way to reinitialize forms, particularly when dynamically injecting them into a page. However, a bug has been identified where this reinitialization process causes a form to submit itself repeatedly in an unending loop. This issue arises specifically when there are multiple forms present on the page – one rendered initially and another injected dynamically. When the umbracoFormsReinitialize event is dispatched, submitting the original form triggers this problematic self-submission cycle. This article will help you to fix the Umbraco forms bug.

This can lead to a poor user experience, server overload, and potential data integrity issues. It's crucial to understand the root cause and implement a solution to prevent this from happening. The core of the problem lies in how the reinitialization process interacts with multiple forms, specifically when one or more forms are added to the DOM dynamically after the page has initially loaded. The event triggers a re-evaluation of the forms, but the logic behind this re-evaluation inadvertently causes the continuous submission. To fully grasp the problem, we need to look at the specifics of how Umbraco Forms handles form initialization and submission, and how the reinitialization process interacts with these mechanisms.

Specifics of the Endless Submit Loop

The Umbraco Forms endless submit loop issue manifests when more than one form exists on a page. Imagine a scenario where you have a standard form rendered on page load and then inject another form via JavaScript. After triggering the umbracoFormsReinitialize event, submitting the initially rendered form kicks off the endless loop. This means the form keeps submitting itself without any further user interaction. This behavior is not only unexpected but also highly disruptive. The reinitialization feature, meant to enhance the dynamic capabilities of Umbraco Forms, unfortunately introduces this unwanted side effect in multi-form scenarios. It highlights the complex interactions between dynamically added content and client-side form handling.

Steps to Reproduce the Issue: A Deep Dive

To fully understand the issue, let's walk through the exact steps to reproduce this Umbraco Forms bug. This will give you a hands-on understanding of the problem and help you verify any potential fixes.

1. Set up a Clean Umbraco Environment: Start with a fresh Umbraco installation, ensuring that only Umbraco Forms is installed. This eliminates any potential conflicts with other packages or customizations.
2. Create a Simple Umbraco Form: Design a basic form within the Umbraco Forms interface. The specific fields aren't critical for reproducing the issue, so a simple form with a few text inputs and a submit button will suffice.
3. Create a Document Type: Define a new Document Type with a template. This document type will be used to create content pages that display the form.
4. Add a Form Picker: Include a Form Picker property to the Document Type. This allows you to select the form you created in the previous step for a content node.
5. Create Content Node: Create content node based on the new Document Type. Then select the simple form in the content node.
6. Craft the Template: This is where the core logic resides. Inside the template, you'll need to:
   • Call @Html.RenderUmbracoFormDependencies(Url): This ensures that all necessary scripts and styles for Umbraco Forms are included.
   • Retrieve the selected form ID from the content node.
   • Render the form using the ViewComponent: `@await Component.InvokeAsync(