owl/doc/learning/environment.md

🦉 Environment 🦉

An environment is an object which contains a QWeb instance. Whenever a root component is created, it is assigned an environment (see the reference section on environment. This environment is then automatically given to each sub components (and accessible in the this.env property).

The environment is mostly static. Each application is free to add anything to the environment, which is very useful, since this can be accessed by each sub component.

Some good use cases for the environment is:

• some configuration keys,
• session information,
• generic services (such as doing rpcs, or accessing local storage).

Doing it this way means that components are easily testable: we can simply create a test environment with mock services.

For example:

async function myEnv() {
  const templates = await loadTemplates();
  const qweb = new QWeb({ templates });
  const session = getSession();

  return {
    _t: myTranslateFunction,
    session: session,
    qweb: qweb,
    services: {
      localStorage: localStorage,
      rpc: rpc
    },
    debug: false,
    inMobileMode: true
  };
}

async function start() {
  App.env = await myEnv();
  const app = new App();
  await app.mount(document.body);
}