site-creation-backend

Creates Isomer sites from FormSG site creation requests

Overview

Isomer allows users to perform certain administrative tasks themselves, namely:

• Creating a GitHub repository and accompanying Netlify sites
• Add and removing users from their GitHub team, and;
• Setting up of KeyCDN for the website, along with DNS aliases (go-live)

This is done through several FormSG forms managed by the Isomer team.

Users have to verify through e-mail that they are Singapore Government personnel in order to use the forms.

Form submissions are then sent via webhook to site-creation-backend to trigger the appropriate calls to GitHub, Netlify and KeyCDN.

Architecture

This application is built using TypeScript and Express.js; code is currently organised into middleware, controllers and services. Controllers make calls to set-up infrastructure through services.

For each form webhook, we mount two controllers, one for webhook payload decryption and one to handle the actual request. This is bootstrapped at express.ts.

site-creation-backend has two possible entrypoints:

• index.ts launches a standard Express.js application
• serverless.ts is an adapter for the application into an AWS Lambda function

Development Setup

• Make copies of the forms using your own FormSG account
  • Take care to use storage mode
• Use ngrok to expose port 8080 on your local machine as a https host on ngrok, ie, npx ngrok https 8080
• Set the webhook of each form to the corresponding path on site-creation-backend on the ngrok host
• Study config.ts to set the appropriate env vars. Note that site-creation-backend will directly manipulate GitHub, Netlify and KeyCDN.
• npm run dev

Deployment

This application is deployed into API Gateway and AWS Lambda; each endpoint exposed is handled by a separate lambda function that happens to share the same codebase.

The lambda codebase in turn is the Express.js application wrapped by serverless-http.