Relay: Efficiently Fetch Data in React Applications Training Course

Relay is a JavaScript framework for building data-driven React applications. GraphQL is a data querying language for describing complex, nested data dependencies in modern applications. Together they allow an application's components to be moved anywhere in a render hierarchy without having to apply a cascade of modifications to parent components or to the server code which prepares the data payload. Relay is being used by Facebook in various mobile app projects.

In this instructor-led, live training, participants will learn how to apply key Relay concepts such as declarative specification of data dependencies, collocation and mutation to build a React application using Relay and GraphQL.

By the end of this training, participants will be able to:

• Use Relay to compose data queries into efficient batches, provide each component with exactly the data that it requested, update the components when the data changes, and maintain a client-side store (cache) of all data.
• Collocate queries and the view's code to more easily reason about a components functionality
• Use GraphQL to declare data requirements while allowing Relay to fetch the data on its own
• Understand the concept of mutating data on the client and server using GraphQL mutations
• Understand the differences between Relay and Flux, in particular how "mutations" implement the concept of actions and modifications
• Use routes to determine which data to fetch to render a given component
• Make changes in relative isolation, even in large team projects
• Create correct, high-performance applications in a straightforward and obvious way

Audience

• Developers

Format of the course

• Part lecture, part discussion, exercises and heavy hands-on practice