Database

This project uses Prisma ORM to simplify interactions with the database, as well as provide a safe way of migrating the database schema.

Diagram

Schema

IMPORTANT

Most of the schemas for authentication (User, Verification, Session, Account) are given by better-auth here. The User schema has been customized to include a few additional fields.

Here's a rough overview of some of the decisions made when designing the database schema:

Element

The Element type represents any element on the canvas. It links to the Image Text and Shape types. Only one of those three can ever be set, but this can't be enforced on the database level. This type could've been implemented as a JSON type in postgres, but i wanted to be able to query objects by zIndex or position with high performance.

Shape

The Shape type encompasses anything that has a fill and stroke. Currently that includes the Circle, Drawing and Rectangle elements.

Member

The Member type represents a user inside of a canvas. It includes the userId and canvasId together as a composite primary key and a role field.

Image & ImageAsset

The ImageAsset type contains the data to access an image on the s3 storage, uploaded by a User to a Project. It can also be directly accessed from either the User or Project type.

Crucially an ImageAsset is a representation of the file itself and not the image on the canvas, which is what the Image type is for. Therefore there can be multiple Images with the same ImageAsset.

Project

The Project has a few different names in the codebase and documentation. It is mostly referred to as either Canvas or when user facing as Book.