Apache OpenWhisk is an Apache Incubator project which provides a complete Serverless, or Function-as-a-Service, platform along with an ecosystem of curated functional packages, client SDKs and integration tooling.
Background
Serverless computing is the evolutionary next stage in Cloud computing carrying further the abstraction offered to software developers using Container-based operating system virtualization. The Serverless paradigm enables programmers to just “write” functional code and not worry about having to configure any aspect of a server needed for execution. Such Serverless functions are single purpose and stateless that respond to event-driven data sources and can be scaled on-demand.
The Apache OpenWhisk Incubator project offers a truly open, highly scalable, performant distributed Serverless platform leveraging other open technologies along with a robust programming model, catalog of service and event provider integrations and developer tooling. Specifically, every architectural component service of the OpenWhisk platform (e.g., Controller, Invokers, Messaging, Router, Catalog, API Gateway, etc.) all is designed to be run and scaled as a Docker container. In addition, OpenWhisk uniquely leverages aspects of Docker engine to manage, load balance and scale supported OpenWhisk runtime environments (e.g., JavaScript, Python, Swift, Java, etc.), that run Serverless functional code within Invoker compute instances, using Docker containers.
OpenWhisk's containerized design tenants not only allows it to be hosted in various IaaS, PaaS Clouds platforms that support Docker containers, but also achieves the high expectation of the Serverless computing experience by masking all aspects of traditional resource specification and configuration from the end user simplifying and accelerating Cloud application development. In order to enable HTTP requests as a source of events, and thus the creation of Serverless microservices that expose REST APIs, OpenWhisk includes an API Gateway that performs tasks like security, request routing, throttling, and logging.