Download
DataLoader is a generic utility to be used as part of your application's data fetching layer to provide a simplified and consistent API over various remote data sources such as databases or web services via batching and caching. A port of the "Loader" API originally developed by @schrockn at Facebook in 2010 as a simplifying force to coalesce the sundry key-value store back-end APIs which existed at the time. At Facebook, "Loader" became one of the implementation details of the "Ent" framework, a privacy-aware data entity loading and caching layer within web server product code. This ultimately became the underpinning for Facebook's GraphQL server implementation and type definitions. DataLoader is a simplified version of this original idea implemented in JavaScript for Node.js services. DataLoader is often used when implementing a graphql-js service, though it is also broadly useful in other situations.
Features
- DataLoader is provided so that it may be useful to build GraphQL services for Node.js
- Batching is not an advanced feature, it's DataLoader's primary feature
- Create loaders by providing a batch loading function
- A batch loading function accepts an Array of keys, and returns a Promise which resolves to an Array of values
- DataLoader allows you to decouple unrelated parts of your application without sacrificing the performance of batch data-loading
- A batch loading function accepts an Array of keys, and returns a Promise which resolves to an Array of values or Error instances
Project Samples
