@graphql-tools/import
Version:
A set of utils for faster development of GraphQL tools
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JavaScript
;
/**
* Exposes a simple and efficient API for interacting with Federation V2's `@link` directives
* according to spec.
*/
Object.defineProperty(exports, "__esModule", { value: true });
exports.FEDERATION_V1 = void 0;
exports.extractLinkImplementations = extractLinkImplementations;
const link_js_1 = require("./link.js");
exports.FEDERATION_V1 = Symbol('Federation_V1');
/**
* This function is for power users who want to develop their own Federation 2 `@link` feature(s).
* It enables you to define and support multiple versions of the feature and to easily reference the named imports.
* This includes official federation features if you choose to implement them yourself.
*
* @example
*
* GraphQL SDL:
* extend schema \@link(url: "https://specs.graphql-hive.com/example/v1.0", import: ["@example"])
*
*
* Code:
* import { extractLinkImplementations } from '@theguild/federation-composition';
* const { matchesImplementation, resolveImportName } = extractLinkImplementations(typeDefs);
*
* if (matchesImplementation('https://specs.graphql-hive.com/example', 'v1.0')) {
* const examples: Record<string, string> = {}
* const exampleName = resolveImportName('https://specs.graphql-hive.com/example', '@example');
* visit(typeDefs, {
* FieldDefinition: node => {
* const example = node.directives?.find(d => d.name.value === exampleName)
* if (example) {
* examples[node.name.value] = (
* example.arguments?.find(a => a.name.value === 'eg')?.value as
* | StringValueNode
* | undefined
* )?.value
* }
* }
* });
* }
*/
function extractLinkImplementations(typeDefs) {
const links = link_js_1.FederatedLink.fromTypedefs(typeDefs);
const linkByIdentity = Object.fromEntries(links.map(l => [l.identity, l]));
// Any schema with a `@link` directive present is considered federation 2
// although according to federation docs, schemas require linking specifically
// the federation 2.x spec. The reason for not being so picky is that supergraphs also
// use @link, but do not necessarily link to the federation 2.x spec.
// Check if any @link or @core features are used.
const supportsFederationV2 = Object.keys(linkByIdentity).length > 0;
return {
links,
resolveImportName: (identity, name) => {
const matchingLink = linkByIdentity[identity];
if (!matchingLink) {
return name.startsWith('@') ? name.substring(1) : name;
}
return matchingLink.resolveImportName(name);
},
matchesImplementation: (identity, version) => {
// Assume Federation 1 means there is no link or identity and so it
// always matches _if_ the typedefs dont use link or core.
if (version === exports.FEDERATION_V1) {
return !supportsFederationV2;
}
const matchingLink = linkByIdentity[identity];
if (!matchingLink) {
return false;
}
if (typeof version === 'string') {
return matchingLink.supports(version);
}
if (version === null) {
return matchingLink.supports(version);
}
return matchingLink.supports(version.major, version.minor);
},
};
}