Prisma Client Lib Hooks

This package is to add hook functionality to prisma-client-lib package.

IMPORTANT: Prisma Photon will have these capabilities built in, but until it's a full release I ended up creating this for myself.

I built this package mainly for synchronization. I prefer to keep any validations, permission or query variable changes specific to a graphql resolver. This allows me to see the uni-direction of the data. The main purpose was if a model is used throughout the app and the CUD operation might come from multiple places. Primary use case is synchronization with other datasources.

Installation

1$ npm install prisma-client-lib prisma-client-lib-hooks

Context

Context that gets passed has the model name, and the parsed ending of the crud operation so that you can concatenate it with another method if needed

1export interface BaseCtx<T extends string> {
2  modelName: T;
3  modelNameFnEnding: string;
4}

Other Info

The create method didn't have a before because I cannot get the id prior to the operation.

Examples

Take a look at ./examples/src/hooks

Example of hook:

1// hook.ts
2import { prisma } from "../generated/prisma-client";
3import { Hook, BaseCtx } from "../../../";
4
5interface Ctx extends BaseCtx<string> {
6    addToContext: boolean;
7}
8
9export class ExampleHook extends Hook {
10    models: { [k: string]: boolean } = {
11        Post: true,
12    };
13    createAfter = async (ids: string[], ctx: Ctx) => {
14        // do something here
15    };
16    deleteBefore = async (ids: string[], ctx: Ctx) => {
17        // do something here
18        ctx.addToContext = true;
19    };
20
21    deleteAfter = async (ids: string[], ctx: Ctx) => {
22        // do something here
23        console.log(ctx.addToContext);
24        // result: true;
25        // ctx state is passed per hook, per CUD
26    };
27    updateAfter = async (ids: string[], ctx: Ctx) => {
28        /*
29        you should use the original initiated prisma that 
30        was generated for doing CRUD actions inside of hooks, 
31        this will prevent circular function calls and keep 
32        it unidirectional
33        */
34        if (ctx.modelName === 'User') {
35            await prisma.deleteManyPosts({})
36        }
37    };
38    updateBefore = async (ids: string[], ctx: Ctx) => {
39        // do something here
40    };
41}
42}

Example of initiating prisma with hooks:

1// index.ts
2import { ExampleHook } from './hook'
3import { Prisma, models, ClientConstructor } from "../generated/prisma-client/index";
4import { typeDefs } from "../generated/prisma-client/prisma-schema";
5
6import { makePrismaClientClass } from "../../../";
7
8
9export const HookedPrisma = makePrismaClientClass<ClientConstructor<Prisma>>({
10    typeDefs,
11    models,
12    endpoint: `${process.env["PRISMA_ENDPOINT"]}`,
13    hooks: [new ExampleHook()]
14});
15export const hookedPrisma = new HookedPrisma();
16