Function Composition in a Serverless World

As serverless applications grow more complex, function composition, or the ability for functions to call each other, becomes important. This talk will dive into three different approaches to compose …

As serverless applications grow more complex, function composition, or the ability for functions to call each other, becomes important. This talk will dive into three different approaches to compose FaaS functions together to form large applications: Coordinating Functions are functions that manage the execution of other functions by calling them directly. Event-driven Composition uses functions emitting and reacting to events on message queue topics. Workflows introduce a mechanism for expressing a graph of function interactions and having a new runtime to manage the execution of these functions. We’ll give examples and live demos for each approach, and compare then on the basis of expressiveness, performance, and fault-tolerance; and also on the basis of operational concerns, such as the ease of doing upgrades, and monitoring the overall application’s performance.