[DRAFT] Angular load external environment properties

AngularExternalConf.md

Use external configuration for your web app (docker, mount volume to /assets/config) Edit maitn.tsin main.ts :

environmentLoader("./assets/config/environment.json", environment).then(env => {
  environment.production = env.production;
  environment.settings = env.settings;
  // Default angular initialization
  if (environment.production) {
    enableProdMode();
  }
  // Example init Logger
  Logger.init(environment.settings.logLevel);
  
  // Default angular initialization
  platformBrowserDynamic().bootstrapModule(AppModule)
    .catch(err => console.error(err));
})

sample /assets/config

{
    "production": false,
    "settings": {
        "logLevel": "INFO",
        "backend": "http://test",
        "keycloakJsonUrl": "./assets/config/keycloak.json",
        "keycloakRedirectUri":"http://localhost:4200/secure"
    }
}

environment-loader.ts

export const environmentLoader = function (path: string = "./assets/confi/environment.json", defaultEnvironment: any = {}): Promise<any> {
    return new Promise<any>((resolve, reject) => {
        var xmlhttp = new XMLHttpRequest(),
            method = 'GET',
            url = path;
        xmlhttp.open(method, url, true);
        xmlhttp.onload = function () {
            if (xmlhttp.status === 200) {
                resolve(JSON.parse(xmlhttp.responseText));
            } else {
                resolve(defaultEnvironment);
            }
        };
        xmlhttp.send();
    });
}