Multiple website support

Cantilever can only build the Cantilever devlog website. The eventual goal is for the project to be more generic than that, so that it can build multiple websites. If I am ever to truly retire bascule, then Cantilever needs to be able to build the https://www.liamjd.org/ blog as well.

I need to add multi-site support to Cantilever, and this will be the biggest change yet. There's a lot to do:

• each project will get its own folder in the sources bucket
• each project needs a unique name and guid
• add permissions to a project in Cognito
• add permissions checks at login and across the project
• add a UI to switch between projects

The real challenge will be in publishing to the destination bucket:

• currently each website is in its own bucket
• how would I grant Cantilever write permission to multiple buckets - especially if those buckets are not configured during CDK deployment?
• or can I put all the generated websites into the same bucket, and have cloudfront or a lambda@edge function
• a temporary fix may be to generate to /project-id/generated/... and then separately copy the content to the true destination bucket

I am worried that Cognito does not give me the control I need. I had assumed that I could add a custom attribute to my cognito user, listing the IDs of the projects it can access. But I've been reading that Cognito does not really support that sort of behaviour, and I'm sure it's not super-secure either (AWS Cognito does not seem to get a lot of love from the community, but I'm not considering switching to another auth solution). I can probably use Cognito Groups to fudge it.

How will I give Cantilever write access to other buckets that are created outside the CDK deployment process? Indeed, where will I record that a particular cantilever project is associated with a particular bucket? That information will probably need to go into cantilever.yaml. What else goes there? I certainly don't want to store actual secrets and keys in this yaml file.

1. Use lambda@edge function to allow me to host multiple websites in a single bucket - done
2. Add a 'domain' property to the project definition file, and use this to set the template output folder - done
3. Write temporary and intermediate files to the project folder in the sources bucket - done

Another problem is my FileUploadHandler lambda - this was triggered by file uploads to the 'sources/' prefix in S3. That common prefix no longer exists, and so file uploads no longer generate page or post rendering. I have had to back to a project architect I had wanted to avoid - a separate intermediate generation bucket. I have started work on this now, but it is a far-reaching change. This is on the back of a lot of earlier rework.

So it's slow going and not a lot of fun. Pretty much every lambda needs significant updates. And lots of update code-deploy-test.