@graphql-mesh/serve-runtime/esm/useCompleteSubscriptionsOnSchemaChange.js

import { createGraphQLError, isAsyncIterable, Repeater } from 'graphql-yoga';
export function useCompleteSubscriptionsOnSchemaChange() {
    const activeSubs = [];
    return {
        onSchemaChange() {
            while (activeSubs.length) {
                activeSubs.pop()?.();
            }
        },
        onSubscribe() {
            return {
                onSubscribeResult({ result, setResult }) {
                    if (isAsyncIterable(result)) {
                        setResult(Repeater.race([
                            result,
                            new Repeater((_push, stop) => {
                                function complete() {
                                    stop(createGraphQLError('subscription has been closed due to a schema reload', {
                                        extensions: {
                                            code: 'SUBSCRIPTION_SCHEMA_RELOAD',
                                        },
                                    }));
                                }
                                activeSubs.push(complete);
                                // eslint-disable-next-line @typescript-eslint/no-floating-promises
                                stop.then(() => {
                                    // eslint-disable-next-line @typescript-eslint/no-floating-promises
                                    result.return?.();
                                    activeSubs.splice(activeSubs.indexOf(complete), 1);
                                });
                            }),
                        ]));
                    }
                },
            };
        },
    };
}