This is the new documentation of Custom Applications. You can still visit the legacy documentation during the migration from Project-level Custom Applications.


Help needed?

This page documents known and recurring challenges with Custom Applications and potential solutions to them.

Something is not working as expected? Do you need general guidance? Do you have a technical question or are you simply looking for some advice?

We strongly encourage and recommend to use GitHub Discussions as a way of communicating with us (commercetools) and with the community. You can ask questions, share ideas, showcase your work, etc.

Additionally, we also recommend checking for existing GitHub Issues about similar problems you might have or opening a new one.

Browser support

commercetools officially supports the latest two versions of all major browsers (Google Chrome, Mozilla Firefox, Apple Safari, Microsoft Edge), unless otherwise noted.

The following browsers are not supported any longer:

  • IE 11 and below

It is recommended to always keep your browser up-to-date for security reasons.

Configuration changes to the Custom Application are not reflected immediately

The first time a user visits the Custom Application route in the Merchant Center, the proxy router fetches the configuration of the Custom Application to determine where to proxy the request to.

This configuration is cached for a certain time within the proxy router to reduce potential latency introduced by validating each incoming request. The cache is automatically updated at a regular interval (the default value is 30 minutes).

This implies that changes to the Custom Application configuration, for example the Application URL, are effectively applied according to the cache interval.

If you are interested in more advanced functionalities, let us know and open a support issue.

Using a test or staging environment for my Custom Application

During the development cycle of new features for a Custom Application, it can be helpful to showcase or test those new features before publishing them to the production environment.

This can usually be accomplished using preview deployments, where you can inspect different versions of the Custom Application. As of now, the Merchant Center does not support this feature yet.

The only option to emulate this setup is to create multiple Custom Applications in the Merchant Center, each with a different entryPointUriPath.

However, the Custom Application must be configured to support dynamic values for the entryPointUriPath and build different versions of it.

Setting up dynamic configurations of Custom Applications (per environment) is further explained in this section.

The same Custom Application can be deployed several times and have its configuration file set to use different entryPointUriPath values by taking advantage of environment variables for each deployment.

Let's say there are two deployments of the same application: A and B. We can assign an environment value for the entryPointUriPath property in its configuration.

"entryPointUriPath": "${env:ENTRY_POINT_URI_PATH}"

The ENTRY_POINT_URI_PATH environment variable can be provided in different ways.

For example:

  • as an inline environment variable when running a script command.

    ENTRY_POINT_URI_PATH=my-application-entry-point mc-scripts start
  • using a dotenv file.

    mc-scripts --env .env-A start
  • by defining the environment variables in your CI service.

Using this pattern, different entryPointUriPath values can be defined for different environments:

  • A environment: my-application-entry-point
  • B environment: my-application-entry-point-test

With this setup, preview versions of the Custom Application can be deployed to the B environment and tested using the application my-application-entry-point-test entry point path.

However, besides using different entryPointUriPath values, the logic of verifying the user permissions in the Custom Application source code must also be adjusted accordingly.

As explained in this section, the permission names of a Custom Application are derived from the entryPointUriPath value. Therefore, when using different entryPointUriPath values, the permission names must also be changed.

We recommend using the helper function entryPointUriPathToPermissionKeys to compute the permission names from the entryPointUriPath.

Find more information on how to apply user permissions in the Permissions documentation.

In this scenario the entryPointUriPath value cannot be defined statically but it's injected using an environment variable.

Therefore, both server-side and client-side logic must be considered when reading the value from the source code.

// Make sure to import the helper functions from the `ssr` entry point.
import { entryPointUriPathToPermissionKeys } from '@commercetools-frontend/application-shell/ssr';
export const entryPointUriPath = typeof window === 'undefined'
? process.env.ENTRY_POINT_URI_PATH
export const PERMISSIONS = entryPointUriPathToPermissionKeys(entryPointUriPath);