vue-di-container

Dependency injection container for Vue (especially class components).

Installation

npm install vue-di-container

Register the plugin:

import { VueDiContainer } from 'vue-di-container';

Vue.use(VueDiContainer);

Usage

Keys

Injectable dependencies are identified by keys. Key is either a class function or an instance of Token<T>. Note that Typescript interfaces will not work.

Defining services

To define injectable service class, use @Service decorator. When container instantiates it, it will inject all constructor arguments (based on declared parameter type or key provided with @Inject decorator) as well as properties marked with @Inject.

import { Inject, Service, Token } from 'vue-di-container';

class ServiceA {}
class ServiceB {}
const TOKEN = new Token<number>('token');

@Service()
class ServiceC {

    @Inject() serviceA!: ServiceA;
    @Inject(ServiceB) serviceB!: any;
    @Inject(TOKEN) token!: number;
    foo!: ServiceA; // not injected as not decorated with @Inject

    constructor(
        serviceA: ServiceA, // injected with ServiceA
        @Inject(TOKEN) token: number,
    ) {}
}

Providers

What actually will be injected into services and components is determined by defined providers. Provider are set in component's options and are inherited by child components (and only them). Services are constructed lazily, only when needed.

@Component({
    diProvide: [
        // Construct instance of ServiceC, inject its dependencies.
        ServiceC,
        // Similar, but register under different key and override some arguments.
        { key: TOKEN, class: ServiceC, args: [ServiceA] },
        // Explicit value.
        { key: TOKEN, value: 7 },
        // Use the result of a function. All arguments must be provided.
        { key: ServiceB, factory: arg => { ... }, args: [TOKEN] },
        // Register existing service under different key.
        { key: TOKEN, aliasOf: ServiceA },
    ],
})
class ComponentA {}

Services that need to be available to all components should be set in Vue root:

new Vue({
    ...
    diProvide: [
        ...
    ],
    render: h => h(App),
}).$mount('#app');

Injecting into components

Only property injection is supported on component classes. Alternatively, there is an option for this.

@Component({})
class ComponentB {

    @Inject() serviceC!: ServiceC;
}

// or

@Component({
    diInject: {
        serviceC: ServiceC,
    },
})
class ComponentC {}

License

MIT, see LICENSE.