graphql-yoga/esm/plugins/request-validation/use-limit-request-body-size.js

import { useLimitRequestBodySize as useWhatwgLimitRequestBodySize } from '@whatwg-node/server';
import { responseFromBodyLimitError } from '../../error.js';
// Must run after all request parsers (built-in and user-provided) have registered, so
// `requestParser` reflects whichever one was ultimately selected. The size-limited request is
// only ever passed to that parser, never assigned back to the outer `request`, so
// `context.request`/plugin hooks keep seeing the exact `Request` object the caller passed in.
export function useLimitRequestBodySize(limit) {
    if (limit === false) {
        return {};
    }
    // Reuses `@whatwg-node/server`'s Content-Length validation and per-chunk byte counting
    // (and its fuller Request reconstruction - cache/credentials/integrity/keepalive/mode/
    // redirect/referrer/referrerPolicy - that a hand-rolled copy here previously dropped),
    // instead of forking that logic. It's built as an `onRequest` plugin, so it's invoked
    // directly below rather than registered as one, to keep its `setRequest` call scoped to
    // the request parser instead of the outer request that becomes `context.request`.
    const limiter = useWhatwgLimitRequestBodySize(limit, {
        responseFromError: responseFromBodyLimitError,
    });
    return {
        onRequestParse({ request, requestParser, setRequestParser, fetchAPI, endResponse, serverContext, url, }) {
            if (requestParser == null) {
                return;
            }
            let wrappedRequest = request;
            // `useLimitRequestBodySize`'s `onRequest` only reads `request`/`setRequest`/`fetchAPI`/
            // `endResponse`; `requestHandler`/`setRequestHandler` are omitted and the payload is cast
            // since we're calling this hook directly instead of registering it as a plugin.
            // `fetchAPI` is the per-request instance from Yoga (native for a native Request), so
            // piping through `fetchAPI.TransformStream` does not cross realms.
            limiter.onRequest?.({
                request,
                setRequest(newRequest) {
                    wrappedRequest = newRequest;
                },
                endResponse,
                fetchAPI,
                serverContext,
                url,
                // unused by the limiter but required to satisfy the payload type
                setRequestHandler: () => { },
                requestHandler: () => new fetchAPI.Response(),
            });
            const originalParser = requestParser;
            setRequestParser(req => originalParser(req === request ? wrappedRequest : req));
        },
    };
}