digital-engagement-platform-skin

This is a front-end service for supplying chat skin to MDTP microservices.

Setup

This application uses node 18.12.1. Follow these steps to set up node locally:

First of all, we need nvm (node version manager, so that we can run node 18.12.1)

curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.36.0/install.sh | bash

With nvm installed, we can set our node version to 18.12.1

nvm install 18.12.1

nvm use 18.12.1

Unit Tests

This application has a considerable amount of JavaScript code, therefore, we have created a set of JS tests to cover the behaviour the system intends.

We use the JS testing framework jest. To install jest locally:

npm install --global jest

We now can run our JS tests with:

jest

To obtain code coverage for a single file:

jest --findRelatedTests app/assets/javascripts/controllers/CommonChatController.js --coverage

For whole service coverage and coverage report of each file:

jest --coverage

JavaScript Build Tool: Webpack

Webpack is used to bundle the various JS files in to one file: app/assets/javascripts/bundle/hmrcChatSkin.ts

To create the bundle manually you must install webpack and webpack-cli globally:

npm install --global webpack

npm install --global webpack-cli

Then run:

webpack build

However, starting the service will bundle the JS code automatically.

Scala & JavaScript Build

Development mode

When developing using the command sbt run, the project is set up to run the start script in the package.json file.

It does this by using a PlayRunHook defined in project/WebpackRunHook.scala, which calls the start script.

This script installs JS dependencies, bundles & minimises the JS code, and recompiles the bundle after changes to JS files:

npm install && webpack --config webpack.config.js --mode=development --watch --optimization-minimize

Build & Deployment

When deployed, the JS bundle is created during the SBT Test stage, using an SBT Setting.

This is because including the setting in the SBT Compile stage caused the bundle to be created multiple times on a developer's machine (At times it took 5 minutes to start the service locally).

Artefacts generated during the Test stage are included in the final build.

Useful commands

To manually remove node modules:

rm -rf node_modules

To reinstall:

npn install

Troubleshooting

Error: Cannot find module 'fs/promises'

This is caused by not using node 18.12.1, run the command nvm install 18.12.1

License

This code is open source software licensed under the Apache 2.0 License.