Answers to common questions about the Hangouts API.
- I need an OAuth 2.0 access token. How do I get one?
Any Hangout App that has an OAuth 2.0 client ID for web applications will ask users for authorization before it starts. You can thus get an OAuth2 token without explicitly asking the user for permission again.
- What is a data URI?
A data URI, as used in the Hangouts API, is a URI that contains the actual encoded data for a png image or WAV sound file. A Hangout app can directly use the data. Data URIs are useful for small sound effects or image overlays because the data lives directly in the web page and loading the data doesn't don't incur the overhead of an extra http call.
For example, this data URI represents a small green circle. Click on this link to see a tiny 7px diameter circle in the upper left corner of your browser (if your browser supports data URIs):