InversifyJS VS typedi

Take a class for which we are tasked to write a unit test. This class may have a dozen methods and a dozen more attributes. In my environment we were already using inversify to dependency inject into this class, and using container snapshot and restore as setup and teardown operators, in our jest test file. But it began getting out of control even after refactoring into test cases and test runners.

Inversify (https://inversify.io/) for IoC.

Alguns frameworks trabalham desta forma por padrão, como é o caso do Angular, quando este não é o padrão do framework que utilizamos podemos usar alguma biblioteca, como a Inversify ou tsyringe da Microsoft.

Using decorators required setting an --experimentalDecorators experimental compiler flag. Several popular TypeScript libraries, such as type-graphql and inversify, rely on this implementation.

inversify

It blows 🤯 my mind to think that my #opensource project InversifyJS has reached over 100 MILLION DOWNLOADS on npm. InversifyJS is a lightweight (<50KB) but powerful Inversion Of Control (IoC) container for #JavaScript applications powered by #TypeScript. It is used to implement Dependency Injection (DI) in thousands of applications, including high-profile products like Microsoft Sway and over forty thousand open source repositories on #GitHub and over two thousand open source packages on #npm.

we use https://inversify.io/ in production, it works great.

In this tutorial, we're building a simple application which uses Cerbos inside of a GraphQL server. The server is written in typescript and uses type-graphql to create the schema and resolvers, and TypeDI to handle dependency injection.

typedi

If you don’t want to tie yourself to a full web framework like Nest, there are a few DI-only frameworks that work with decorators, like TypeDI, TSyringe, or Typed Inject.

For existing projects, or if you don't want the weight of an opinionated framework like Nest, libraries like TypeDI and TSyringe can help.

The TypeDI project aims for simplicity by leveraging decorators and decorator metadata. It supports dependency scoping with singletons and transient objects and allows for multiple DI containers to exist. You have two options for working with TypeDI:

There are a number of Javascript dependency injection container libraries out there. Some of my personal favourites are TypeDI and InversifyJS. Here is an example demonstrating basic usage of Typedi with JavaScript.

typedi TypeDI is a powerful dependency injection package that has many features. One of this features is having Singleton Services which is how we use it in our case.