1555 Build endpoint for sending project updates

[dhochbaum-dcp]

Summary

Build new endpoint to trigger project update emails for given project

• New POST endpoint to /projects/<projectid>/send-update
• Calls Sendgrid APIs to create single sends for project to correct CD and citywide lists with correct metadata.
• Endpoint requires Authorization header implementing Basic authorization method. Credentials should be username:password base64 encoded. Username can be ae-admin, password should be randomly generated UUID to be stored as environment variable. If given authorization header contains incorrect credentials, return 401 Unauthorized response.
• If single sends are created and scheduled succesfully, return 200
• If project with given id not found, return 404

Tasks/Bug Numbers

• Closes Build endpoint for sending project updates #1555

Technical Explanation

I ended up not needing to add any dependencies for this endpoint. 🎉

We did not need anything to manage users, since we do not have multiple users. Basic authorization only requires that we ensure that the username:password base64 encoded sent with the request is correct. I added a module/service to handle this portion. Because this is a different authentication than is used elsewhere on the server, and is limited to a single endpoint, I was able to put the authorization in the controller, rather than needing to add it as middleware.

We had discussed potentially using Handlebars, but there did not appear to be any packages that provide out-of-the-box support for our use case. There is support for either using Handlebars as your primary means of templating, and support for using Handlebars to precompile your site using a CLI; but they are not suited for importing a Handlebars template, populating it on the fly, and returning an HTML string. Because of this, it would be overkill for us to come up with a complex implementation when the MVP requires only a single email template for this purpose, when instead we could simply use template literals.

Any other info you think would help a reviewer understand this PR?

[netlify]

✅ Deploy Preview for labs-zap ready!

Name	Link
🔨 Latest commit	53e99ae
🔍 Latest deploy log	https://app.netlify.com/sites/labs-zap/deploys/6760728d78fb6c0008190d4d
😎 Deploy Preview	https://deploy-preview-1616--labs-zap.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site configuration.