Providers

Providers are DI units that expose data or services. They can depend on other providers and may define onReady and onClose hooks.

import { provider } from "@stratify/core";

const UsersRepository = provider({
  name: "usersRepository",
  expose: () => ({
    get: (id) => ({ id, name: "Ada" }),
  }),
  // Optional hooks:
  onReady: async ({ deps, value }) => { /* Some setup */},
  onClose: async ({ deps, value }) => { /* Some cleanup */},
});

// Domain service depending on another provider
const Profiles = provider({
  name: "profiles",
  // You can also do `deps: { UsersRepository }`
  deps: { usersRepo: UsersRepository },
  expose: ({ usersRepo }) => ({
    find: async (id) => usersRepo.get(id),
  }),
});

Encapsulation

Providers are not encapsulated within a specific module scope but managed globally by the DI container.

The same applies to any hooks they define. This is why a provider cannot declare onReady/onClose hooks (global scope) and contract dependencies (bound at module scope) at the same time.

Testing

Use withProviders() and resolve() to replace dependencies and exercise a provider in isolation. For integration and end-to-end tests, bootstrap the application with global overrides and access registered providers through app.ioc.

See Testing for complete examples and the differences between both strategies.