@sparkstone/solid-validation

A lightweight and flexible form validation library for Solid.js. It provides a simple API to validate form inputs, handle submission state, and manage error messages.

Installation

npm install @sparkstone/solid-validation

or

pnpm add @sparkstone/solid-validation

Table of Contents

• Usage
  • Basic Example
• API
  • useForm(options?: { errorClass?: string })
    • validate
    • formSubmit
    • errors
    • isSubmitting
    • isSubmitted
    • validateRef
    • validateField
    • getFieldValue
• Custom Validation
  • Example Validator
• PocketBase Integration
  • prepareFormDataForPocketbase
  • parsePocketbaseError

Usage

Basic Example

import { createSignal } from 'solid-js';
import { useForm } from '@sparkstone/solid-validation';

function min5Characters(el: HTMLInputElement) {
  if (el.value.length < 5) {
    return 'must be at least 5 characters long';
  }
}

function MyForm() {
  const { formSubmit, validate, errors, isSubmitting, isSubmitted } = useForm();

  async function onSubmit(form: HTMLFormElement) {
    const formData = new FormData(form);

    try {
      // Submit form data here
    } catch (e) {
      return {
        myCustomFormError: e.message,
      };
    }
  }

  return (
    <form use:formSubmit={onSubmit}>
      <input type='text' name='username' placeholder='Enter username' required use:validate />
      <span>{errors.username}</span>

      <input
        type='text'
        name='message'
        placeholder='Enter message'
        required
        use:validate={[min5Characters]}
      />
      <span>{errors.message}</span>

      <span>{errors.myCustomFormError}</span>

      <button type='submit' disabled={isSubmitting()}>
        {isSubmitting() ? 'Submitting...' : 'Submit'}
      </button>

      {isSubmitted() && <p>Form successfully submitted!</p>}
    </form>
  );
}

function required(el: HTMLInputElement) {
  return el.value.trim() ? false : 'This field is required';
}

API

useForm(options?: { errorClass?: string })

Creates a form validation context.

Returns:

• validate(ref: HTMLInputElement, validators?: Validator[])
  Registers an input for validation.

• formSubmit(ref: HTMLFormElement, callback: OnFormSubmit)
  Handles form submission, running all validations.

• errors: Partial<Record<string, string>>
  Reactive store of validation errors.

• isSubmitting: () => boolean
  Tracks whether the form is currently submitting.

• isSubmitted: () => boolean
  Tracks whether the form was successfully submitted.

• validateRef: (...args: Parameters<typeof validate>) => (ref: HTMLInputElement) => void
  If you're validating a custom element, you can pass this in with ref={validateRef()}.

• validateField(fieldName: keyof ErrorFields): Promise<boolean> Validates a field based on its name. It returns true if the field is valid. If the field fails validation, it automatically focuses the field and updates the error state.

• getFieldValue(fieldName: keyof ErrorFields) Retrieves the current value of the specified field. This is useful when you need to access a field’s value programmatically during form interactions.

Custom Validation

A validator function receives an HTMLInputElement and returns:

• false | "" | null | undefined for valid inputs.
• A string error message for invalid inputs.
• A Promise<string | Falsy> for async validation.

Example:

function minLength(el: HTMLInputElement) {
  return el.value.length < 5 && 'Must be at least 5 characters';
}

PocketBase Integration

For integrating form validation with PocketBase, this package provides helper functions to prepare form data and handle errors from PocketBase responses.

prepareFormDataForPocketbase(formData: FormData, form: HTMLFormElement)

PocketBase does not include unchecked checkboxes in FormData submissions. This function ensures that all checkbox fields are included, defaulting to "false" if unchecked.

Example:

import { prepareFormDataForPocketbase } from '@sparkstone/solid-validation/pocketbase';

function handleSubmit(event: Event) {
  event.preventDefault();
  const form = event.currentTarget as HTMLFormElement;
  const formData = new FormData(form);

  prepareFormDataForPocketbase(formData, form);

  // Now formData is ready to be sent to PocketBase
}

parsePocketbaseError(error: PocketbaseError, rootErrorKey = "form")

PocketBase API errors return a structured data object. This function extracts error messages and formats them for easy use in your validation logic.

Example:

import { parsePocketbaseError } from '@sparkstone/solid-validation/pocketbase';

async function handleSubmit(event: Event) {
  event.preventDefault();
  const form = event.currentTarget as HTMLFormElement;
  const formData = new FormData(form);

  try {
    // Replace with your PocketBase API call
    await pocketbase.collection('users').create(formData);
  } catch (e) {
    const errors = parsePocketbaseError(e);
    console.log(errors); // { email: "Invalid email", password: "Too short", form: "Something went wrong" }
  }
}

This allows for easy mapping of errors to form fields and a general error message under the "form" key.

---

These functions help streamline form submissions and error handling when using PocketBase as your backend.