Enabling the API

Now that we have a project and we have both the API and service account keys, we will enable the required API and test our application:

1. Navigate to the project home page (https://console.cloud.google.com/home/dashboard?project=smart-exchange-b10882). From the menu on the left-hand side, select APIs & Services | Library.
2. Once we land on this page, search for Vision API and click on that card.

3. Then, click the Enable button. This will prompt you to set up billing as follows:

4. Click on ENABLE BILLING. You will be asked to select or create a new billing account:

5. Click on CREATE BILLING ACCOUNT.

6. Fill in the form as shown on the following screens and validate your payment. Once that is done, you will be automatically redirected to the Enable API page and the API will be automatically enabled for you, if everything is set up correctly. Finally, you should...