Function middleware

packages/gitbook/src/middleware.ts:39–66

(request: NextRequest)

type URLWithMode = { url: URL; mode: 'url' | 'url-host' };

export async function middleware(request: NextRequest) {
    try {
        const requestURL = new URL(request.url);

        // Redirect to normalize the URL
        const normalized = normalizeURL(requestURL);
        if (normalized.toString() !== requestURL.toString()) {
            return NextResponse.redirect(normalized.toString());
        }

        // Reject malicious requests
        const rejectResponse = await validateServerActionRequest(request);
        if (rejectResponse) {
            return rejectResponse;
        }

        for (const handler of [serveSiteRoutes, serveSpacePDFRoutes]) {
            const result = await handler(requestURL, request);
            if (result) {
                return result;
            }
        }

        return NextResponse.next();
    } catch (error) {
        return serveErrorResponse(error as Error);
    }
}

async function validateServerActionRequest(request: NextRequest) {
    // First thing we need to do is validate that the header is in a correct format.