trpc-sveltekit/dist/server.js

SvelteKit adapter for tRPC.io, working with Node.js, Vercel and Netlify

import { resolveHTTPResponse } from '@trpc/server/http';
import { serialize } from 'cookie';
/**
 * Create a SvelteKit handle function for tRPC requests.
 *
 * If you want to use it in conjunction with other SvelteKit handles,
 * consider [the sequence helper function](https://kit.svelte.dev/docs/modules#sveltejs-kit-hooks).
 * @see https://kit.svelte.dev/docs/hooks
 */
export function createTRPCHandle({ router, url = '/trpc', createContext, responseMeta, onError }) {
    return async ({ event, resolve }) => {
        if (event.url.pathname.startsWith(url + '/')) {
            const request = event.request;
            const req = {
                method: request.method,
                headers: request.headers,
                query: event.url.searchParams,
                body: await request.text()
            };
            // Using the default `event.setHeaders` and `event.cookies` will not work
            // as the event in not resolved by SvelteKit. Instead, we "proxy" the access
            // to the headers.
            const originalSetHeaders = event.setHeaders;
            const originalSetCookies = event.cookies.set;
            const originalDeleteCookies = event.cookies.delete;
            const headersProxy = {};
            const cookiesProxy = {};
            // Same as the one provided from sveltekit
            const defaultCookiesOptions = {
                httpOnly: true,
                sameSite: 'lax',
                secure: event.url.hostname === 'localhost' && event.url.protocol === 'http:' ? false : true
            };
            event.setHeaders = (headers) => {
                for (const [key, value] of Object.entries(headers)) {
                    headersProxy[key] = value;
                }
                // Still call the original `event.setHeaders` function, as it may be used in SvelteKit internals.
                originalSetHeaders(headers);
            };
            event.cookies.set = (name, value, options) => {
                cookiesProxy[name] = { value, options: { ...defaultCookiesOptions, ...options } };
                originalSetCookies(name, value, options);
            };
            event.cookies.delete = (name, options) => {
                cookiesProxy[name] = { value: '', options: { ...options, maxAge: 0 } };
                originalDeleteCookies(name, options);
            };
            const httpResponse = await resolveHTTPResponse({
                router,
                req,
                path: event.url.pathname.substring(url.length + 1),
                createContext: async () => createContext?.(event),
                responseMeta,
                // eslint-disable-next-line @typescript-eslint/no-explicit-any
                onError: onError
            });
            const { status, headers, body } = httpResponse;
            const finalHeaders = new Headers();
            for (const [key, value] of Object.entries(headers)) {
                finalHeaders.set(key, value);
            }
            for (const [key, value] of Object.entries(headersProxy)) {
                finalHeaders.set(key, value);
            }
            if (Object.keys(cookiesProxy).length > 0) {
                for (const [name, { value, options }] of Object.entries(cookiesProxy)) {
                    const serializedCookie = serialize(name, value, options);
                    finalHeaders.append('Set-Cookie', serializedCookie);
                }
            }
            return new Response(body, { status, headers: finalHeaders });
        }
        return resolve(event);
    };
}