Document how to handle 4XX or 5XX error codes in GraphQL loaders

[JulienPradet]

WIP documentation for withDefault404Result

4XX or 5XX HTTP error codes are throwing errors when using axios. But this is not always the wanted behavior in a GraphQL schema. This is especially true for 404 errors that shouldn't throw but return null in a GraphQL resolver.

One can use withDefault404Result(promise, defaultResult) from node_modules/front-commerce/src/server/core/graphql/queryResponseBuilders.js to handle such case.

For instance, if you want to fetch a product but return null, you could do :

const {
  withDefault404Result
} = require("server/core/graphql/queryResponseBuilders");

const loadProduct = withDefault404Result(
  fetch(`/product/${sku}`).then(response => response.data),
  null
);