how can I show customized error messaged from server side validation in React Admin package?

Question

Is there any way to perform server side form validation using https://github.com/marmelab/react-admin package?

Here\'s the code for AdminCreate Component. It sends c

Answer 1

In addition to Christiaan Westerbeek's answer. I just recreating a SimpleForm component with some of Christian's hints. In begining i tried to extend SimpleForm with needed server-side validation functionality, but there were some issues (such as not binded context to its handleSubmitWithRedirect method), so i just created my CustomForm to use it in every place i need.

import React, { Children, Component } from 'react';
import PropTypes from 'prop-types';
import { reduxForm, SubmissionError } from 'redux-form';
import { connect } from 'react-redux';
import compose from 'recompose/compose';
import { withStyles } from '@material-ui/core/styles';
import classnames from 'classnames';
import { getDefaultValues, translate } from 'ra-core';
import FormInput from 'ra-ui-materialui/lib/form/FormInput';
import Toolbar  from 'ra-ui-materialui/lib/form/Toolbar';
import {CREATE, UPDATE} from 'react-admin';
import { showNotification as showNotificationAction } from 'react-admin';
import { push as pushAction } from 'react-router-redux';

import dataProvider from "../../providers/dataProvider";

const styles = theme => ({
    form: {
        [theme.breakpoints.up('sm')]: {
            padding: '0 1em 1em 1em',
        },
        [theme.breakpoints.down('xs')]: {
            padding: '0 1em 5em 1em',
        },
    },
});

const sanitizeRestProps = ({
   anyTouched,
   array,
   asyncValidate,
   asyncValidating,
   autofill,
   blur,
   change,
   clearAsyncError,
   clearFields,
   clearSubmit,
   clearSubmitErrors,
   destroy,
   dirty,
   dispatch,
   form,
   handleSubmit,
   initialize,
   initialized,
   initialValues,
   pristine,
   pure,
   redirect,
   reset,
   resetSection,
   save,
   submit,
   submitFailed,
   submitSucceeded,
   submitting,
   touch,
   translate,
   triggerSubmit,
   untouch,
   valid,
   validate,
   ...props
}) => props;

/*
 * Zend validation adapted catch(e) method.
 * Formatted as
 * e = {
 *    field_name: { errorType: 'messageText' }
 * }
 */
const submit = (data, resource) => {
    let actionType = data.id ? UPDATE : CREATE;

    return dataProvider(actionType, resource, {data: {...data}}).catch(e => {
        let errorObject = {};

        for (let fieldName in e) {
            let fieldErrors = e[fieldName];

            errorObject[fieldName] = Object.values(fieldErrors).map(value => `${value}\n`);
        }

        throw new SubmissionError(errorObject);
    });
};

export class CustomForm extends Component {
    handleSubmitWithRedirect(redirect = this.props.redirect) {
        return this.props.handleSubmit(data => {
            return submit(data, this.props.resource).then((result) => {
                let path;

                switch (redirect) {
                    case 'create':
                        path = `/${this.props.resource}/create`;
                        break;
                    case 'edit':
                        path = `/${this.props.resource}/${result.data.id}`;
                        break;
                    case 'show':
                        path = `/${this.props.resource}/${result.data.id}/show`;
                        break;
                    default:
                        path = `/${this.props.resource}`;
                }

                this.props.dispatch(this.props.showNotification(`${this.props.resource} saved`));

                return this.props.dispatch(this.props.push(path));
            });
        });
    }

    render() {
        const {
            basePath,
            children,
            classes = {},
            className,
            invalid,
            pristine,
            push,
            record,
            resource,
            showNotification,
            submitOnEnter,
            toolbar,
            version,
            ...rest
        } = this.props;

        return (
            

                

                    {Children.map(children, input => {
                        return (
                            
                        );
                    })}
                
                {toolbar &&
                React.cloneElement(toolbar, {
                    handleSubmitWithRedirect: this.handleSubmitWithRedirect.bind(this),
                    invalid,
                    pristine,
                    submitOnEnter,
                })}
            
        );
    }
}

CustomForm.propTypes = {
    basePath: PropTypes.string,
    children: PropTypes.node,
    classes: PropTypes.object,
    className: PropTypes.string,
    defaultValue: PropTypes.oneOfType([PropTypes.object, PropTypes.func]),
    handleSubmit: PropTypes.func, // passed by redux-form
    invalid: PropTypes.bool,
    pristine: PropTypes.bool,
    push: PropTypes.func,
    record: PropTypes.object,
    resource: PropTypes.string,
    redirect: PropTypes.oneOfType([PropTypes.string, PropTypes.bool]),
    save: PropTypes.func, // the handler defined in the parent, which triggers the REST submission
    showNotification: PropTypes.func,
    submitOnEnter: PropTypes.bool,
    toolbar: PropTypes.element,
    validate: PropTypes.func,
    version: PropTypes.number,
};

CustomForm.defaultProps = {
    submitOnEnter: true,
    toolbar: ,
};

const enhance = compose(
    connect((state, props) => ({
        initialValues: getDefaultValues(state, props),
        push: pushAction,
        showNotification: showNotificationAction,
    })),
    translate, // Must be before reduxForm so that it can be used in validation
    reduxForm({
        form: 'record-form',
        destroyOnUnmount: false,
        enableReinitialize: true,
    }),
    withStyles(styles)
);

export default enhance(CustomForm);

For better understanding of my catch callback: In my data provider i do something like this

...
    if (response.status !== 200) {
         return Promise.reject(response);
    }

    return response.json().then((json => {

        if (json.state === 0) {
            return Promise.reject(json.errors);
        }

        switch(type) {
        ...
        }
    ...
    }
...