SSR fetch doesn't work for external requests

[koffeinfrei]

Describe the bug

Using fetch in SSR treats requests as relative with the default config value of "" (empty string) for options.paths.base, instead of as an external request.

The reason is the statement

kit/packages/kit/src/runtime/server/page/load_node.js

Line 113 in 2a1e979

} else if (resolved.startsWith(options.paths.base || '/')) {

that always resolves to true with the default value.

Reproduction

<script context="module">
  export async function load({ fetch }) {
      const result = await fetch('https://duckduckgo.com/');
     // --> result is not from duckduckgo, but from the svelte-kit app
  }
</script>

Logs

No response

System Info

npx: installed 1 in 0.935s

  System:
    OS: Linux 5.11 Ubuntu 21.04 (Hirsute Hippo)
    CPU: (4) x64 Intel(R) Core(TM) i7-7600U CPU @ 2.80GHz
    Memory: 963.18 MB / 15.38 GB
    Container: Yes
    Shell: 5.1.4 - /bin/bash
  Binaries:
    Node: 12.20.0 - ~/.nvm/versions/node/v12.20.0/bin/node
    Yarn: 1.12.3 - /usr/bin/yarn
    npm: 6.14.8 - ~/.nvm/versions/node/v12.20.0/bin/npm
  Browsers:
    Chromium: 92.0.4515.107
    Firefox: 90.0

Severity

blocking all usage of SvelteKit

Additional Information

No response

[benmccann]

Are you using the latest version of SvelteKit? This should have been fixed in #1980

https://duckduckgo.com/ doesn't start with / so I don't see from the code how it would fail

[koffeinfrei]

Are you using the latest version of SvelteKit? This should have been fixed in #1980

Right, this has been fixed right between me detecting the bug and reporting it. Sorry for the noise.