Schemix

Easily create modular Prisma schemas.

Welcome to Schemix. An easy-to-use TypeScript layer over designing Prisma schemas, allowing for modularization, mixins, and other added capabilities.

Installation · Setup · Usage · Contribute

Installation

To install Schemix, simply use your favourite Node.js package manager.

yarn add schemix

npm install schemix

Setup

You will need to create three folders that will contain your source files for your Prisma schema.

enums/
mixins/
models/

Your resulting file structure for your project may end up looking like what follows.

project/
├── node_modules/
│   └── *
├── prisma/
│   ├── index.ts
│   ├── schema.prisma
│   ├── enums/
│   │   └── Status.enum.ts
│   ├── mixins/
│   │   ├── DateTime.mixin.ts
│   │   └── UUID.mixin.ts
│   └── models/
│       ├── Post.model.ts
│       └── User.model.ts
├── index.ts
├── tsconfig.json
└── package.json

Once that's set up, you can add a script to your package.json in your root directory for your project which runs the prisma/index.ts file, thus generating the schema.prisma. file. Any time you generate your @prisma/client, you should first re-run the schemix script.

Usage

You can see an example usage in the example/ folder in this repository.

Schema Index

// ./index.ts

import { createSchema } from "schemix";

createSchema({
  // basePath should be a path to the folder containing models/, enums/, and mixins/.
  basePath: __dirname,
  datasource: {
    provider: "postgresql",
    url: { env: "DATABASE_URL" },
  },
  generator: {
    provider: "prisma-client-js",
  },
}).export(__dirname, "schema");

Model Structure

// ./models/User.model.ts

import { createModel } from "schemix";

import PostModel from "./Post.model";
import UUIDMixin from "../mixins/UUID.mixin";

export default createModel((UserModel) => {
  UserModel.mixin(UUIDMixin)
    .relation("friends", UserModel, { list: true, name: "friends" })
    .relation("friendsRelation", UserModel, { list: true, name: "friends" })
    .relation("posts", PostModel, { list: true });
});

As you can see, you can self-reference, and cross-reference relations, apply mixins, etc.

Override Resulting Model Name

The model name will default to the name of the file, if you want to override this behaviour, simply pass it in as the first parameter in the createModel function.

// ./models/User.model.ts

import { createModel } from "schemix";

import PostModel from "./Post.model";
import UUIDMixin from "../mixins/UUID.mixin";

export default createModel("UserModel", (UserModel) => {
  UserModel.mixin(UUIDMixin)
    .relation("friends", UserModel, { list: true, name: "friends" })
    .relation("friendsRelation", UserModel, { list: true, name: "friends" })
    .relation("posts", PostModel, { list: true });
});

Extending Models

Sometimes one model is derivative of another, and the extension feature can be quite useful for this.

If we want to extend the PostModel to create an ImagePostModel which has all its old properties but with an imageUrl string column, we can do so without having to re-write every single other attribute.

// ./models/ImagePost.model.ts

import { extendModel } from "schemix";

import PostModel from "./Post.model";

export default extendModel(PostModel, (ImagePostModel) => {
  ImagePostModel.string("imageUrl");
});

Contribute

Feel free to contribute to the repository. Pull requests and issues with feature requests are super welcome!

seanlowe/schemix