@cocalc/database

This package connects the hub and nextjs servers to the PostgreSQL database, and implements some nontrivial functionality to support these servers. In particular:

• It implements changefeeds and user queries, which provides a pure JSON language similar to the basics of GraphQL for setting, getting, and subscribing to data in the database. This uses PostgreSQL LISTEN/NOTIFY to send push notifications about changes to tables. It's specifically designed for our data structures, of course, and is not generic. The data structures are currently defined in @cocalc/util/db-schema.

Notes

WARNING: This is the single scariest chunk of CoffeeScript left in CoCalc!

Temporary Warning: There is a circular dependency between this package and @cocalc/server right now. That's necessary while we rewrite the coffeescript code. What happened was that these files postgres-*.coffee ended up implementing hundreds amount of "server functions" that have nothing to do with basic database functionality. They need to be rewritten in lots of small typescript files, mostly in @cocalc/server.