@graphql-yoga/apollo-managed-federation/esm/index.js

This plugin integrates Apollo Managed Federation into Yoga.

import { createGraphQLError } from 'graphql-yoga';
import { SupergraphSchemaManager, } from '@graphql-tools/federation';
export function useManagedFederation(options = {}) {
    const { supergraphManager = new SupergraphSchemaManager(options), } = options;
    const plugin = {
        onYogaInit({ yoga }) {
            supergraphManager.on('log', ({ level, message, source }) => {
                yoga.logger[level](`[ManagedFederation]${source === 'uplink' ? ' <UPLINK>' : ''} ${message}`);
            });
            supergraphManager.on('failure', options.onFailure ??
                ((error, delayInSeconds) => {
                    const message = error?.message ?? error;
                    yoga.logger.error(`[ManagedFederation] Failed to load supergraph schema.${message ? ` Last error: ${message}` : ''}`);
                    yoga.logger.info(`[ManagedFederation] No failure handler provided. Retrying in ${delayInSeconds}s.`);
                    supergraphManager.start(delayInSeconds);
                }));
            supergraphManager.start();
        },
        onPluginInit({ setSchema }) {
            if (supergraphManager.schema) {
                setSchema(supergraphManager.schema);
            }
            else {
                // Wait for the first schema to be loaded before before allowing requests to be parsed
                // We can then remove the onRequestParse hook to avoid async cost on every request
                const waitForInitialization = new Promise((resolve, reject) => {
                    const onFailure = (err) => {
                        reject(createGraphQLError('Supergraph failed to load', {
                            originalError: err instanceof Error ? err : null,
                        }));
                    };
                    supergraphManager.once('failure', onFailure);
                    supergraphManager.once('schema', schema => {
                        setSchema(schema);
                        supergraphManager.off('failure', onFailure);
                        resolve();
                        plugin.onRequestParse = undefined;
                    });
                });
                plugin.onRequestParse = async () => {
                    await waitForInitialization;
                };
            }
            supergraphManager.on('schema', setSchema);
        },
    };
    return plugin;
}