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hooks.js example causes a build error

See original GitHub issue

Describe the bug

When the following hooks.js file exists, npm run build throws an error. (However npm run dev works without error and the site runs perfectly.)

To Reproduce

Add src/hooks.js

export async function handle(request, render) {
  const response = await render(request);

  return {
    ...response,
    headers: {
      ...response.headers,
      'x-custom-header': 'potato'
    }
  };
}

Run npm run build.

The command will throw this error:

✓ 38 modules transformed.
.svelte/output/server/app.js      193.07kb
.svelte/output/server/style.css   7.76kb

Run npm start to try your app locally.

> Using @sveltejs/adapter-node
TypeError: Cannot read property 'headers' of undefined
    at Object.handle (file:///Users/me/sveltekit-demo/.svelte/output/server/app.js:1890:19)
    at async ssr (file:///Users/me/sveltekit-demo/.svelte/output/server/app.js:1677:12)
    at async visit (file:///Users/me/sveltekit-demo/node_modules/@sveltejs/kit/dist/chunks/index5.js:531:20)
    at async prerender (file:///Users/me/sveltekit-demo/node_modules/@sveltejs/kit/dist/chunks/index5.js:682:5)
    at async Builder.prerender (file:///Users/me/sveltekit-demo/node_modules/@sveltejs/kit/dist/chunks/index5.js:743:4)
    at async adapt (/Users/me/sveltekit-demo/node_modules/@sveltejs/adapter-node/index.js:26:4)
    at async adapt (file:///Users/me/sveltekit-demo/node_modules/@sveltejs/kit/dist/chunks/index5.js:765:2)
    at async file:///Users/me/sveltekit-demo/node_modules/@sveltejs/kit/dist/cli.js:598:5
> 500 /about
Error: 500 /about
    at error (file:///Users/me/sveltekit-demo/node_modules/@sveltejs/kit/dist/chunks/index5.js:523:11)
    at visit (file:///Users/me/sveltekit-demo/node_modules/@sveltejs/kit/dist/chunks/index5.js:574:5)
    at async prerender (file:///Users/me/sveltekit-demo/node_modules/@sveltejs/kit/dist/chunks/index5.js:682:5)
    at async Builder.prerender (file:///Users/me/sveltekit-demo/node_modules/@sveltejs/kit/dist/chunks/index5.js:743:4)
    at async adapt (/Users/me/sveltekit-demo/node_modules/@sveltejs/adapter-node/index.js:26:4)
    at async adapt (file:///Users/me/sveltekit-demo/node_modules/@sveltejs/kit/dist/chunks/index5.js:765:2)
    at async file:///Users/me/sveltekit-demo/node_modules/@sveltejs/kit/dist/cli.js:598:5
npm ERR! code 1
npm ERR! path /Users/me/sveltekit-demo
npm ERR! command failed
npm ERR! command sh -c svelte-kit build

about.svelte is nothing special:

<h1>About this site</h1>
<p>TODO...</p>

svelte.config.cjs contains adapter as: adapter: node(),.

Information about your SvelteKit Installation:

  System:
    OS: macOS 11.2.2
    CPU: (8) arm64 Apple M1
    Shell: 5.8 - /bin/zsh
 npmPackages:
    @sveltejs/kit: next => 1.0.0-next.64 
    svelte: ^3.35.0 => 3.35.0

Severity

Minor

Issue Analytics

State:
Created 2 years ago
Reactions:1
Comments:20 (8 by maintainers)

Top GitHub Comments

1reaction

vaib1343commented, Jan 29, 2022

config.kit.ssr has been removed — use the handle hook instead: https://kit.svelte.dev/docs#hooks-handle. how can i resolve this issue

1reaction

Rich-Harriscommented, Apr 2, 2021

In the process of trying to figure out how we’d tackle this, I ended up writing the code, so I took the liberty of opening a PR: https://github.com/sveltejs/kit/pull/833