How to create custom validators in Retool forms?

 

Creating Custom Validators in Retool Forms

 

Utilizing custom validators in Retool forms can ensure data integrity and provide a more interactive user experience. This guide presents a step-by-step method to create and implement these validators effectively in Retool.

 

Understanding Retool and Basic Concepts

 

• Retool is a platform that enables users to build internal tools with flexible user interfaces.
• Basic understanding of JavaScript and Retool's component properties will be beneficial.
• Familiarize yourself with Retool's environment, particularly the form component as it will be the primary focus.

 

Setting Up Your Retool Form

 

• Log into your Retool account and open the project where you wish to add the form.
• Navigate to the canvas and use the drag-and-drop feature to add a Form component onto your page.
• Inside the form, add necessary input components (e.g., Text Inputs, Dropdowns) based on your application needs.

 

Adding Basic Validation

 

• For each input component, access the component Inspector pane on the right side of the screen.
• Locate the 'Validation' section, where basic validations like 'Required' and 'Pattern' can be set according to simple data rules.

 

Implementing Custom Validators

 

• Custom validations require writing JavaScript within Retool's interface.
• Select the form input you want to validate and scroll to the bottom of the Inspector.
• Click on the 'Custom Validation' toggle to enable JavaScript-based validation capability.

 

Writing JavaScript for Validation

 

• In the custom validator input box, write JavaScript code to return a boolean indicating the validity of the input.
• Example: return value.length > 8 && /[0-9]/.test(value);
• This example validates that the input is longer than 8 characters and contains a number.
• Use Retool’s built-in JavaScript helpers, such as utils, if necessary.
• Consider edge cases and test the validation logic thoroughly to ensure reliability.

 

Linking Validation Logic to Form Behavior

 

• Once the custom validator is in place, connect it to form actions by specifying settings in the Form component.
• In the form's Inspector panel, set behavior for 'Submit' button to be conditional on all validations passing.
• For visual feedback, configure components to display error messages or indicators when validation fails.

 

Testing Your Custom Validation Logic

 

• Enter various test inputs that challenge both the happy path and edge cases for your custom validator.
• Use Retool’s Debug mode to analyze errors and adjust validation code as needed.
• Review console logs through the Debugger Pane to track validation processes.

 

Deploying the Application With Custom Validation

 

• Once validated, deploy your Retool app ensuring that all configurations are set for production.
• Review error handling and user feedback mechanisms to verify they operate correctly in a live environment.
• Conduct user acceptance testing (UAT) with actual users to ensure the application meets functional requirements.

 

Following these steps, you should be able to confidently implement and customize form validation inside Retool, leveraging the flexibility of custom JavaScript within the tool's ecosystem to support complex validation requirements specific to your application's needs.