Skip to main content

Getting Started

Quick Start in 4 Steps​

Get up and running with typectx in just a few minutes.

1. Installation​

npm install typectx

2. Import flat APIs​

Use the flat service APIs directly.

import { service } from "typectx"

3. Define Services​

Services create your app's dependencies. Request services hold data from the user's request (request params, cookies, etc.), which cannot be derived from other services, while App Services are your application's services, components or features. They are factory functions that depend on request data or other app services. Factories can return anything: simple values, promises or other functions.

Names passed to service("...") can only contain digits, letters, underscores or $ signs and cannot start with a digit, just like any Javascript identifier.

// A Request service for the user session
const $session = service("session").request<{ userId: string }>()

// An app service that depends on the session
const $userService = service("userService").app({
    services: [$session],
    // Access the session by destructuring the factory's 1st argument.
    // The property name is the service name passed to service("...").
    factory: ({ session }) => {
        return {
            id: session.userId,
            name: "Jane Doe"
        }
    }
})

4. Assemble at Your Entry Point​

At your application's entry point, assemble your main service, providing any required request data. The index() utility simplifies this process.

import { index } from "typectx"

const session = { userId: "user-123" }

// Assemble the user service with a concrete session
const userService = $userService
    .assemble(index($session.pack(session)))
    .unpack()

console.log(userService.id) // "user-123"

Next Steps​