README.md

@saritasa/react-form

This is a package for simple form building.

Install:

npm install @saritasa/react-form

Available components:

• Form
• FormField
• FormFieldError
• FormError
• FormOuterControlsProvider

Available methods:

• createFieldRules

Components

<Form />

<Form> is a component that helps you with building forms.

import React from 'react';
import { Form } from '@saritasa/react-form';

const View = props => (
  <form onSubmit={props.onSubmit}>
    <input
       type="text"
     onChange={props.onChange}
     onBlur={props.onBlur}
     value={props.values.name}
     name="name"
   />
   {props.errors.name && <div id="feedback">{props.errors.name}</div>}
   <button type="submit">Submit</button>
 </form>
); 

const handleSubmit = (values, actions) => {
 setTimeout(() => {
   alert(JSON.stringify(values, null, 2));
   actions.setSubmitting(false);
 }, 1000);
};

const BasicExample = () => (
  <div>
    <h1>My Form</h1>
    <Form
      initialValues={{ name: 'jared' }}
      onSubmit={handleSubmit}
      component={View}
    />
  </div>
);

Form's View props

All three render methods will be passed the same props:

dirty: boolean

Returns true if values are not deeply equal from initial values, false otherwise. dirty is a readonly computed property and should not be mutated directly.

errors: { [field: string]: ?string }

Form validation errors. Should match the shape of your form's [values] defined in initialValues.

error: ?string

Form validation errors. Should match the shape of your form's [values] defined in initialValues.

onBlur: (event: SyntheticFocusEvent<HTMLElement>) => void

onBlur event handler. Useful for when you need to track whether an input has been [touched] or not. This should be passed to <input onBlur={handleBlur} ... />

DOM-only. Use [setFieldTouched] in React Native.

onChange: (event: SyntheticInputEvent<HTMLElement>) => void

General input change event handler. This will update the values[key] where key is the event-emitting input's name attribute. If the name attribute is not present, handleChange will look for an input's id attribute. Note: "input" here means all HTML inputs.

DOM-only. Use [setFieldValue] in React Native.

onReset: () => void

Reset handler. Will reset the form to its initial state. This should be passed to <button onClick={handleReset}>...</button>

onSubmit: (e: SyntheticEvent<HTMLFormElement>) => void

Submit handler. This should be passed to <form onSubmit={props.onSubmit}>...</form>

submitting: boolean

Submitting state. Either true or false. Form will set this to true on your behalf before calling [onSubmit] to reduce boilerplate.

valid: boolean

Returns true if the there are no [errors], or the result of [initialValid] the form if is in "pristine" condition (i.e. not [dirty])).

resetForm: (nextValues?: Values) => void

Imperatively reset the form. This will clear [errors] and [touched], set [submitting] to false and rerun mapPropsToValues with the current WrappedComponent's props or what's passed as an argument. The latter is useful for calling resetForm within componentWillReceiveProps.

setErrors: (fields: { [field: string]: ?string }) => void

Set errors imperatively.

setFieldError: (field: string, errorMsg: ?string) => void

Set the error message of a field imperatively. field should match the key of [errors] you wish to update. Useful for creating custom input error handlers.

setFieldTouched: (field: string, isTouched: boolean, shouldValidate?: boolean) => void

Set the touched state of a field imperatively. field should match the key of [touched] you wish to update. Useful for creating custom input blur handlers. Calling this method will trigger validation to run if [validateOnBlur] is set to true (which it is by default). You can also explicitly prevent/skip validation by passing a third argument as false.

submitForm: () => void

Trigger a form submission.

setFieldValue: (field: string, value: any, shouldValidate?: boolean) => void

Set the value of a field imperatively. field should match the key of [values] you wish to update. Useful for creating custom input change handlers. Calling this will trigger validation to run if [validateOnChange] is set to true (which it is by default). You can also explicitly prevent/skip validation by passing a third argument as false.

setStatus: (status?: any) => void

Set a top-level [status] to anything you want imperatively. Useful for controlling arbitrary top-level state related to your form. For example, you can use it to pass API responses back into your component in [onSubmit].

setSubmitting: (submitting: boolean) => void

Set [submitting] imperatively.

setTouched: (fields: { [field: string]: boolean }) => void

Set [touched] imperatively.

setValues: (fields: { [field: string]: any }) => void

Set [values] imperatively.

status?: any

A top-level status object that you can use to represent form state that can't otherwise be expressed/stored with other methods. This is useful for capturing and passing through API responses to your inner component.

status should only be modifed by calling setStatus: (status?: any) => void

touched: { [field: string]: boolean }

Touched fields. Each key corresponds to a field that has been touched/visited.

values: { [field: string]: any }

Your form's values. Will have the shape of the result of [mapPropsToValues] (if specified) or all props that are not functions passed to your wrapped component.

validateForm: (values?: any) => void

Imperatively call your [validate] or [validateSchema] depending on what was specified. You can optionally pass values to validate against and this modify Form state accordingly, otherwise this will use the current values of the form.

component

<Form component={ContactForm} />;

const ContactForm = ({
  onSubmit,
  onChange,
  onBlur,
  values,
  errors,
}) => (
  <form onSubmit={onSubmit}>
    <input
      type="text"
      onChange={onChange}
      onBlur={onBlur}
      value={values.name}
      name="name"
    />
    {errors.name && <div>{errors.name}</div>}
    <button type="submit">Submit</button>
  </form>
);

enableReinitialize?: boolean

Default is false. Control whether Form should reset the form if [initialValues] changes (using deep equality).

initialValid?: boolean

Default is false. Control the initial value of [isValid] prop prior to mount. You can also pass a function. Useful for situations when you want to enable/disable a submit and reset buttons on initial mount.

initialValues?: Values

Initial field values of the form, Form will make these values available to render methods component as [props.values][values].

Even if your form is empty by default, you must initialize all fields with initial values otherwise React will throw an error saying that you have changed an input from uncontrolled to controlled.

Note: initialValues not available to the higher-order component, use [mapPropsToValues] instead.

onReset?: (values: Values, formBag: FormBag) => void

Your optional form reset handler. It is passed your forms [values] and the "FormBag".

onSubmit: (values: Values, formBag: FormBag) => void

Your form submission handler. It is passed your forms [values] and the "FormBag", which includes an object containing a subset of the injected props and methods (i.e. all the methods with names that start with set<Thing> + resetForm) and any props that were passed to the the wrapped component.

Note: [errors], [touched], [status] and all event handlers are NOT included in the FormBag.

validate?: (values: Values) => FormErrors<Values> | Promise<any>

Note: I suggest using [validationSchema] and Yup for validation. However, validate is a dependency-free, straightforward way to validate your forms.

Validate the form's [values] with function. This function can either be:

1. Synchronous and return an [errors] object.

// Synchronous validation
const validate = (values, props) => {
  let errors = {};

  if (!values.email) {
    errors.email = 'Required';
  } else if (!/^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$/i.test(values.email)) {
    errors.email = 'Invalid email address';
  }

  //...

  return errors;
};

• Asynchronous and return a Promise that's error in an [errors] object

// Async Validation
const sleep = ms => new Promise(resolve => setTimeout(resolve, ms))

const validate = (values, props) => {
  return sleep(2000).then(() => {
    let errors = {}
    if (['admin', 'null', 'god'].includes(values.username)) {
      errors.username = 'Nice try'
    }
    // ...
    if (Object.keys(errors).length) {
      throw errors
    }
  })
}

validateOnBlur?: boolean

Default is true. Use this option to run validations on blur events. More specifically, when either [handleBlur], [setFieldTouched], or [setTouched] are called.

validateOnChange?: boolean

Default is true. Use this option to tell Form to run validations on change events and change-related methods. More specifically, when either [handleChange], [setFieldValue], or [setValues] are called.

validationSchema?: Schema | (() => Schema)

A Yup schema or a function that returns a Yup schema. This is used for validation. Errors are mapped by key to the inner component's [errors]. Its keys should match those of [values].

Methods

createFieldRules()

import { createFieldRules } from 'components/base/Form';

function myRule(values) {
  if (values.a === 1) {
    return { ...values, b: 2 };
  }

  return values;
}

function mySecondRule(values) {
  if (values.b === 2) {
    return { ...values, c: 3 };
  }

  return values;
}

function myBrokenRule(values) {
  if (values.a === 1) {
    values.b = 2; // <<--- This pattern is forbidden. Always create new object in case of any change.
  }

  return values;
}

const r1 = createFieldRules(myRule);
const r2 = createFieldRules([myRule]);
const r3 = createFieldRules([myRule, mySecondRule]);
const r4 = createFieldRules([mySecondRule, myRule]);
const r5 = createFieldRules(myBrokenRule);

r1({ a: 1, b: 1 }) // { a;
r1({ a: 0, b: 1 });
r5({ a: 1, b: 1 });