LaravelValidator.js

data: ()=>({
    validator: new Validator
}),

/**
* Validator API
*/
this.validator.clear()
this.validator.all()
this.validator.has('myField')
this.validator.get('myField', ['Please enter a default value.', 'Also do something else.'])
this.validator.first('myField', 'Please enter a default value.')
this.validator.in(['email', 'password'])
this.validator.firstEntry
this.validator.isInvalid
this.validator.sync(error)
this.validator.setMessage('Invalid Request.')
this.validator.setErrors({
  myField: ["Min length 5 chars."]
})

export default class Validator{
    constructor(){
        this.message = null
        this.messageBag = {}
    }

    /**
     * (Method) clearErrors
     * @return void
     */
    clear() {
        this.setErrors({})
    }

    /**
     * All Errors
     * @return {Object}
     */
    all() {
        return this.messageBag
    }

    /**
     * Sync State
     * @param error {AxiosError}
     */
    sync(error) {
        if(
            error.response &&
            error.response.data &&
            error.response.data.errors
        ){
            const errors = error.response.data.errors
            for (let key of Object.keys(errors)) {
                errors[key].map((error, index) => {
                    //Strip Dot Syntax from Field Names in Messages (for nested array fields)
                    errors[key][index] = error.replace(
                        key.replace(/_/g, ' '),
                        key.replace(/[._]/g, ' ')
                    )
                })
            }
            this.messageBag = errors
            this.setMessage(error.response.data.message || error.message)
        }
        return this
    }

    /**
     * Set Response Message
     * @param message @type {String}
     */
    setMessage(message = null){
        this.message = message
    }

    /**
     * Set Errors
     * @param messageBag
     */
    setErrors(messageBag = {}){
        this.messageBag = messageBag
    }

    /**
     * (Conditional) hasErrors
     * @param field @type {String}
     * @return {boolean}
     */
    has(field = null) {
        return field ? this.messageBag.hasOwnProperty(field) : false
    }
    /**
     * (Method) getErrors
     * @param field @type {String}
     * @param fallback @type {*}
     * @return {*}
     */
    get(field, fallback = []) {
        return this.messageBag.hasOwnProperty(field) ? this.messageBag[field] : fallback ? fallback : null
    }
    /**
     * (Method) getError
     * @param field @type {String}
     * @param fallback @type {*}
     * @return {String|null}
     */
    first(field = null, fallback = false) {
        return this.messageBag.hasOwnProperty(field) ? this.messageBag[field][0] : fallback ? fallback : null
    }
    /**
     * (Conditional) hasErrorsIn
     * @param fields @type {Array}
     * @return {Boolean}
     */
    in(...fields) {
        let hasErrors = false
        fields.some((field) => {
            hasErrors = this.messageBag.hasOwnProperty(field)
            return hasErrors
        })
        return hasErrors
    }
    /**
     * (Method) firstEntry
     * @return {String|null}
     */
    get firstEntry() {
        const errors = Object.values(this.messageBag).flat(2);
        return errors.length > 0 ? errors[0] : null
    }

    /**
     * In Invalid
     * @return {boolean}
     */
    get isInvalid(){
        return Object.entries(this.messageBag).length > 0
    }
}