Prism/developer documentation/Handlers

Handlers

Where your module's logic lives, shared by routes, clocks and events.

A handler holds your module's logic. Routes, clocks and events stay short and call into it. Put handlers in src/handlers/.

modules/example/src/handlers/items.js

import { Handlers } from "#prism/modules";

export class ItemsHandler extends Handlers {
    constructor(prism) {
        super(prism, { name: "items" });
    }

    get items() {
        return this.prism.modules.models.get("example", "example_items");
    }

    async create(identifier, name) {
        if (!identifier) this.fail(400, this.prism.modules.lang.phrase("example", "messages", "identifier_required"));
        if (await this.items.get({ identifier })) this.fail(409, this.prism.modules.lang.phrase("example", "messages", "exists", { identifier }));
        return this.items.plain(await this.items.create({ identifier, name }));
    }
}

this.module is your module ID, set by Prism when it loads the file. Messages that reach customers come from your lang files, never inline strings.

Methods

Method	What it does
`fail(status, message)`	Throws an error with that HTTP status. A route that hits it answers with the status and `{ error: message }`.
`emit(event, ...args)`	Fires an event on `this.prism.events`.
`emitAsync(event, ...args)`	Fires an event and waits for every listener.
`getName()`	The handler name.

Using Another Module's Handler

const catalog = this.prism.modules.handlers.get("core", "catalog");

get returns null when that module is not loaded. If your module cannot work without it, add it to requires in main.js instead of checking each time.

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