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@ngxp/environment

Loads the Angular environment at runtime instead of build-time.

Why

Normally Angular's environment configuration is provided by importing environment from the environment folder and replaced with the specific stage configuration at build-time.

If you are working with Docker images this means you have to build a new image for each stage/environment which can be a potential cause of errors.

That's why we want to build an image once and use it across all stages/environments. So we have to load environment-specific configuration at runtime instead of build-time and this library helps with that.

Usage

In the main.ts file of your Angular application wrap the bootstrap logic with fetchEnvironment(...) and add the ENVIRONMENT provider to the platformBrowserDynamic function

import { ENVIRONMENT, fetchEnvironment } from '@ngxp/environment';

fetchEnvironment().then(env => {
    if (env.production) {
        enableProdMode();
    }

    platformBrowserDynamic([
        {
            provide: ENVIRONMENT,
            useValue: env
        }
    ])
        .bootstrapModule(AppModule)
        .catch((err) => console.error(err));
});

This will load a JSON configuration from <PROTOCOL>//<HOST>/environment before the Angular application starts. Additionally the fetchEnvironment function can be called with a path parameter

fetchEnvironment(`http://example.org/my/custom/environment.json`).then(env => {
  ...
});

The environment configuration can now be used by using the ENVIRONMENT InjectionToken in your application.

import { ENVIRONMENT } from '@ngxp/environment';

@Component({
    selector: 'app-root',
    templateUrl: './app.component.html',
    styleUrls: ['./app.component.scss']
})
export class AppComponent {

    constructor(
        private environment: ENVIRONMENT,
    ) { }
}

Troubleshooting

fetch

The fetchEnvironment uses the fetch method in the background. So you might have to install whatwg-fetch and add import 'whatwg-fetch' in your polyfills.ts.