Documentation

Notifications

Learn about notification types and how to use them in your customizations.

In this section, we'll look at how to provide feedback to users using a customization's built-in notification system.

Notification system

Notifications are an important means of providing feedback to users within your customizations, especially in response to user actions. For example, when a form submission succeeds or fails, the user should be informed about this in an understandable and thoughtful way.

Notifications are grouped by so-called domains. A domain specifies where the notification should be displayed on the page (for instance page and side).

The following notification types are available: success, error, warning, and info. Depending on the use case, you can choose the appropriate notification type to display. For example, if a form was submitted successfully, you would display a side notification of the type success.

To trigger a notification, you can use the custom React hooks provided by the @commercetools-frontend/actions-global package.

For defining the domain and the kind of a notification, we recommend using the values exposed from @commercetools-frontend/constants.

For example:

import { useShowNotification } from '@commercetools-frontend/actions-global';
import {
  DOMAINS,
  NOTIFICATION_KINDS_SIDE,
  NOTIFICATION_KINDS_PAGE,
} from '@commercetools-frontend/constants';


const showNotification = useShowNotification();


// success notification in side domain
showNotification({
  kind: NOTIFICATION_KINDS_SIDE.success,
  domain: DOMAINS.SIDE,
  text: 'Success 🎉',
});


// warning notification in page domain
showNotification({
  kind: NOTIFICATION_KINDS_PAGE.warning,
  domain: DOMAINS.PAGE,
  text: 'Warning ⚠️',
});

Be mindful of your users when dispatching notifications. Excessive and confusing notifications can lead to a poor user experience.

Page notifications

Page notifications are displayed on top of a content page. By default, the notifications must be closed manually. We recommend that you only use page notifications in Custom Applications.

Generally, error notifications should be displayed in the page domain rather than the side domain.

For defining the kind of page notification, we recommend using the NOTIFICATION_KINDS_PAGE constant exposed from @commercetools-frontend/constants. The available values defined by the constant are error, warning, info, success, unexpected-error and api-error.

Page notifications

Side notifications

Side notifications are smaller than page notifications and they slide in from the right side of the page. Success notifications in the side domain by default disappear after 5 seconds.

We recommend displaying success notifications in the side domain.

For defining the kind of side notification we recommend using NOTIFICATION_KINDS_SIDE constant exposed from @commercetools-frontend/constants. The available values defined by the constant are error, warning, info and success.

Side notifications

Using notifications in a form

Let's implement notifications in the details page of our Channels application.

The following code example shows useApplicationContext, which is applicable to Custom Applications. If you're working with Custom Views, you'll need to use useCustomViewContext instead.

Form submitted successfully

channels-details.jsJavaScript
import { useCallback } from 'react';
import { useRouteMatch } from 'react-router-dom';
import { useApplicationContext } from '@commercetools-frontend/application-shell-connectors';
import { FormModalPage } from '@commercetools-frontend/application-components';
import LoadingSpinner from '@commercetools-uikit/loading-spinner';
import { useShowNotification } from '@commercetools-frontend/actions-global';
import {
  DOMAINS,
  NOTIFICATION_KINDS_SIDE,
} from '@commercetools-frontend/constants';
import useChannelsFetcher from './use-channels-fetcher';
import useChannelsUpdater from './use-channels-updater';
import { docToFormValues, formValuesToDoc } from './conversions';
import ChannelsForm from './channels-form';


const ChannelsDetails = (props) => {
  const match = useRouteMatch();
  const languages = useApplicationContext(
    (context) => context.project.languages
  );
  const { data: channel } = useChannelsFetcher(match.params.id);
  const { updateChannel } = useChannelsUpdater(match.params.id);
  const showNotification = useShowNotification();
  const handleSubmit = useCallback(
    async (formValues) => {
      const data = formValuesToDoc(formValues);
      try {
        await updateChannel(data);
        showNotification({
          kind: NOTIFICATION_KINDS_SIDE.success,
          domain: DOMAINS.SIDE,
          text: 'Channel updated! 🎉',
        });
      } catch (graphQLErrors) {
        // show an error notification
      }
    },
    [showNotification, updateChannel]
  );


  if (!channel) {
    return <LoadingSpinner />;
  }


  return (
    <ChannelsForm
      initialValues={docToFormValues(channel, languages)}
      onSubmit={handleSubmit}
    >
      {(formProps) => {
        return (
          <FormModalPage
            title="Manage Channel"
            isOpen
            onClose={props.onClose}
            isPrimaryButtonDisabled={formProps.isSubmitting}
            onSecondaryButtonClick={formProps.handleCancel}
            onPrimaryButtonClick={formProps.submitForm}
          >
            {formProps.formElements}
          </FormModalPage>
        );
      }}
    </ChannelsForm>
  );
};

Form submitted with errors

In most cases, displaying error notifications is the result of handling API errors. For example, when a form is rejected by the API. In this section, we will look at some examples of API error handling for GraphQL and REST API requests.

GraphQL

Find more information about GraphQL errors in the Apollo Client docs.

The basic implementation of dispatching error notifications in the Channels application looks like this:

channels-details.jsJavaScript
// ...
import { useShowApiErrorNotification } from '@commercetools-frontend/actions-global';


const ChannelsDetails = (props) => {
  // ...
  const showApiErrorNotification = useShowApiErrorNotification();
  const handleSubmit = useCallback(
    async (formValues) => {
      const data = formValuesToDoc(formValues);
      try {
        // ...
      } catch (graphQLErrors) {
        const errors = Array.isArray(graphQLErrors)
          ? graphQLErrors
          : [graphQLErrors];
        if (errors.length > 0)
          showApiErrorNotification({
            errors,
          });
      }
    },
    [showApiErrorNotification /* ... */]
  );


  // ...
};

Following our recommendations, not all GraphQL errors should lead to dispatching an error notification. For example, instead of displaying an error notification, we can try to map specific errors to their related form fields.

In the following code snippet, we take advantage of the fact that a Channel's key value must be unique. A request to update the Channel's key to a duplicated value results in an error with the DuplicateField error code.

Find more information about API errors on the API errors page.

For this purpose, we recommend creating an error transforming function:

transform-errors.jsJavaScript
import omitEmpty from 'omit-empty-es';


const DUPLICATE_FIELD_ERROR_CODE = 'DuplicateField'; // A particular error code returned by API that we wish to map to form field validation error


export const transformErrors = (graphQlErrors) => {
  const errorsToMap = Array.isArray(graphQlErrors)
    ? graphQlErrors
    : [graphQlErrors];


  const { formErrors, unmappedErrors } = errorsToMap.reduce(
    (transformedErrors, graphQlError) => {
      const errorCode = graphQlError?.extensions?.code ?? graphQlError.code;
      const fieldName = graphQlError?.extensions?.field ?? graphQlError.field;


      if (errorCode === DUPLICATE_FIELD_ERROR_CODE) {
        transformedErrors.formErrors[fieldName] = { duplicate: true };
      } else {
        transformedErrors.unmappedErrors.push(graphQlError);
      }
      return transformedErrors;
    },
    {
      formErrors: {}, // will be mappped to form field error messages
      unmappedErrors: [], // will result in dispatching `showApiErrorNotification`
    }
  );


  return {
    formErrors: omitEmpty(formErrors),
    unmappedErrors,
  };
};

In the form onSubmit handler, we can then transform the errors, render them in the form (if needed) and dispatch an error notification.

channels-details.jsJavaScript
// ...
import { transformErrors } from './transform-errors';


const ChannelsDetails = (props) => {
  // ...
  const handleSubmit = useCallback(
    async (formValues, formikHelpers) => {
      const data = formValuesToDoc(formValues);
      try {
        // ...
      } catch (graphQLErrors) {
        const transformedErrors = transformErrors(graphQLErrors);
        if (transformedErrors.unmappedErrors.length > 0)
          showApiErrorNotification({
            errors: transformedErrors.unmappedErrors,
          });


        formikHelpers.setErrors(transformedErrors.formErrors);
      }
    },
    [
      /* ... */
    ]
  );
  // ...
};

DuplicateField errors related to the key field will be transformed to form validation errors. All other errors are transformed into API error notifications.

REST

For HTTP requests sent to REST API, we follow the same pattern used in GraphQL:

channels-details-rest.jsJavaScript
import { useEffect } from "react";
import { useAsyncDispatch, actions } from "@commercetools-frontend/sdk";
import { MC_API_PROXY_TARGETS } from "@commercetools-frontend/constants";
import {
  useShowNotification,
  useShowApiErrorNotification,
} from "@commercetools-frontend/actions-global";
import { DOMAINS, NOTIFICATION_KINDS_SIDE } from "@commercetools-frontend/constants";


const ChannelsDetails = (props) => {
  const dispatch = useAsyncDispatch();
  const showNotification = useShowNotification();
  const showApiErrorNotification = useShowApiErrorNotification();
  useEffect(() => {
    async function execute() {
      try {
        const result = await dispatch(
          actions.post({
            mcApiProxyTarget: MC_API_PROXY_TARGETS.COMMERCETOOLS_PLATFORM,
            service: "channels",
            options: { /* ... */ },
            payload: {
              // ...
            },
          })
        );
        // Update state with `result`
        showNotification({
          kind: NOTIFICATION_KINDS_SIDE.success,
          domain: DOMAINS.SIDE,
          text: "Channel updated! 🎉",
        });
      } catch (error) {
        // Update state with `error`
        showApiErrorNotification({ errors: error.body?.errors ?? [] });
      }
    }
    execute();
  }, [dispatch]);


  return (
    // ...
  );
};

Usage with React class components

If a notification must be dispatched from a React class component, we cannot use React hooks exposed from the @commercetools-frontend/actions-global package. Instead, we should use a Redux action directly.

The following is a basic example of dispatching notifications:

channel-updater.jsJavaScript React
import { Component } from 'react';
import { connect } from 'react-redux';
import {
  showNotification,
  showApiErrorNotification,
} from '@commercetools-frontend/actions-global';
import { DOMAINS, NOTIFICATION_KINDS_SIDE } from '@commercetools-frontend/constants';
// ...


class ChannelsDetails extends Component {
  handleSubmit = (update) => async (formikValues) => {
    try {
      await update(formikValues);
      this.props.dispatch(
        showNotification({
          kind: NOTIFICATION_KINDS_SIDE.success,
          domain: DOMAINS.SIDE,
          text: 'Channel updated! 🎉',
        })
      );
    } catch (graphQLErrors) {
      const errors = Array.isArray(graphQLErrors)
        ? graphQLErrors
        : [graphQLErrors];
      if (errors.length > 0) {
        this.props.dispatch(
          showApiErrorNotification({
            errors,
          })
        );
      }
    }
  };
  render() {
    return (
      // ...
    );
  }
}
export default connect()(ChannelsDetails);

Testing

When testing notifications, we recommend that you use the test render function for your specific customization type: