SSR is case sensitive for headers (content-type)

[Max9403]

Describe the bug
The content-type header field is case-sensitive, adding graphql to a clean project will cause it to error with Cannot read property 'split' of undefined but making it fully lower case manually allows it to function as expected

Graphql adds a fetch in load with the content type header named as Content-Type making it lower case makes it work

Logs

Log

> svelte-kit dev

Debugger listening on ws://127.0.0.1:57865/df48eb33-d329-4a79-983a-6807c41c0db1
For help, see: https://nodejs.org/en/docs/inspector
Debugger attached.

SvelteKit v1.0.0-next.107

network: not exposed
network: not exposed
network: not exposed
local: http://localhost:3000
network: not exposed
network: not exposed

Use --host to expose server to other devices on this network

A component can only have one <script context="module"> element
ParseError: A component can only have one <script context="module"> element
at error (E:\dev\rafael\IOT\webobtron\node_modules.pnpm\svelte@3.38.2\node_modules\svelte\compiler.js:16752:20)
at Parser$1.error (E:\dev\rafael\IOT\webobtron\node_modules.pnpm\svelte@3.38.2\node_modules\svelte\compiler.js:16828:10)
at parse$3 (E:\dev\rafael\IOT\webobtron\node_modules.pnpm\svelte@3.38.2\node_modules\svelte\compiler.js:16937:17)
at compile (E:\dev\rafael\IOT\webobtron\node_modules.pnpm\svelte@3.38.2\node_modules\svelte\compiler.js:30012:18)
at compileSvelte (E:\dev\rafael\IOT\webobtron\node_modules.pnpm@sveltejs+vite-plugin-svelte@1.0.0-next.10_svelte@3.38.2+vite@2.3.2\node_modules@sveltejs\vite-plugin-svelte\dist\index.js:244:48)
at async TransformContext.transform (E:\dev\rafael\IOT\webobtron\node_modules.pnpm@sveltejs+vite-plugin-svelte@1.0.0-next.10_svelte@3.38.2+vite@2.3.2\node_modules@sveltejs\vite-plugin-svelte\dist\index.js:837:27)
at async Object.transform (E:\dev\rafael\IOT\webobtron\node_modules.pnpm\vite@2.3.2\node_modules\vite\dist\node\chunks\dep-efbff8d5.js:44155:30)
at async transformRequest (E:\dev\rafael\IOT\webobtron\node_modules.pnpm\vite@2.3.2\node_modules\vite\dist\node\chunks\dep-efbff8d5.js:58421:29)
at async instantiateModule (E:\dev\rafael\IOT\webobtron\node_modules.pnpm\vite@2.3.2\node_modules\vite\dist\node\chunks\dep-efbff8d5.js:68026:10)
12:38:32 [vite] page reload src/routes/index.svelte
Cannot read property 'split' of undefined
TypeError: Cannot read property 'split' of undefined
at parse_body (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:1383:60)
at respond (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:1514:11)
at fetch (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:731:30)
at load (index.svelte:13:30)
at load_node (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:818:30)
at respond$1 (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:1039:21)
at async render_page (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:1186:20)
at async render (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:1537:10)
at async Object.handle (e:/dev/webobtron/src/hooks.ts:14:24)
at async respond (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:1510:10)
Unexpected token T in JSON at position 0
SyntaxError: Unexpected token T in JSON at position 0
at JSON.parse ()
at Proxy. (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:790:22)
at async load (index.svelte:22:33)
at async load_node (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:818:12)
at async respond$1 (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:1039:15)
at async render_page (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:1186:20)
at async render (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:1537:10)
at async Object.handle (e:/dev/webobtron/src/hooks.ts:14:24)
at async respond (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:1510:10)
at async Immediate. (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/chunks/index.js:3305:23)

To Reproduce
npm init svelte@next
npx svelte-add graphql
npm run dev
open http://localhost:3000

Expected behavior
It to parse content-type header correctly

Stacktraces

Stack trace

Cannot read property 'split' of undefined
TypeError: Cannot read property 'split' of undefined
at parse_body (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:1383:60)
at respond (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:1514:11)
at fetch (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:731:30)
at load (index.svelte:13:30)
at load_node (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:818:30)
at respond$1 (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:1039:21)
at async render_page (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:1186:20)
at async render (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:1537:10)
at async Object.handle (e:/dev/webobtron/src/hooks.ts:14:24)
at async respond (file:///E:/dev/webobtron/node_modules/.pnpm/@sveltejs+kit@1.0.0-next.107_svelte@3.38.2/node_modules/@sveltejs/kit/dist/ssr.js:1510:10)

Information about your SvelteKit Installation:

Diagnostics

System:
OS: Windows 10 10.0.19042
CPU: (16) x64 Intel(R) Core(TM) i7-7820X CPU @ 3.60GHz
Memory: 37.30 GB / 63.68 GB
Binaries:
Node: 15.9.0 - C:\Program Files\nodejs\node.EXE
Yarn: 1.22.10 - ~\AppData\Roaming\npm\yarn.CMD
npm: 7.12.1 - C:\Program Files\nodejs\npm.CMD
Watchman: 20210110.135312.0 - E:\dev\tools\watchman\bin\watchman.EXE
Browsers:
Edge: Spartan (44.19041.964.0), Chromium (90.0.818.62)
Internet Explorer: 11.0.19041.1
npmPackages:
@sveltejs/kit: next => 1.0.0-next.107
svelte: ^3.38.2 => 3.38.2

• Your browser
  Firefox nightly

• Your adapter (e.g. Node, static, Vercel, Begin, etc...)
  The default?

Severity
Annoying