Chapter 1. Running functions in the cloud
Figure 1.1. An event-driven, media-sharing application built using multiple AWS Lambda functions, some invoked directly by the mobile app. Other functions are subscribed to storage repositories such as a file share or a database.
Figure 1.2. Calling an AWS Lambda function synchronously with the RequestResponse invocation type. Functions receive input as an event and a context and return a result.
Figure 1.3. Calling an AWS Lambda function asynchronously with the Event invocation type. The invocation returns immediately while the function continues its work.
Figure 1.4. Functions can create, update, or delete other resources. Resources can also be other services that can do some actions, such as sending an email.
Figure 1.5. Functions can subscribe to events generated by direct use of resources, or by other functions interacting with resources. For resources not managed by AWS, you should find the best way to generate events to subscribe functions to those resources.
Figure 1.6. How users interact via the internet with the back end of an application. Note that the back end has some logic and some data.
Figure 1.7. Different ways in which users can interact with the back end of an application. Users using a web browser receive different data than other front end clients.
Figure 1.8. Using a JavaScript application running in the browser, back end architecture is simplified by serving only APIs to all clients.