For applications such as ours that have multiple modules, we need to list out all the YAML files for the goapp command.

To serve our new application, in a terminal, execute this:

goapp serve dispatch.yaml default/app.yaml api/app.yaml
     web/app.yaml

Starting with the dispatch file, we are listing all the associated configuration files. If you miss any, you will see an error when you try to serve your application. Here, you will notice that the output now lists that each module is being deployed on a different port:

We can access modules directly by visiting each port, but luckily we have our dispatcher running on port :8080, which will do that for us based on the rules we specified in our dispatch.yaml configuration file.

Testing locally

Now that we have built our application, head over to localhost:8080 to see it in action. Use the features of the application by performing the following steps:

1. Log in using your real e-mail address (that way, you'll see your Gravatar picture).
2. Ask a question.
3. Submit a couple of answers.
4. Vote the answers up and down and see the scores changing.
5. Open another browser and sign in as someone else to see what the application looks like from their point of view.

Using the admin console

The admin console is running alongside our application and is accessible at localhost:8000:

Datastore Viewer lets you inspect the data of your application. You can use it to see (and even make changes to) the questions, answers, and votes data that are being generated as you use the application.

Automatically generated indexes

You can also see which indexes have been automatically created by the development server in order to satisfy the queries your application makes. In fact, if you look in the default folder, you will notice that a new file called index.yaml has magically appeared. This file describes those same indexes that your application will need, and when you deploy your application, this file goes up to the cloud with it to tell Google Cloud Datastore to maintain these same indexes.