CORS and cache issues with Block GETs #121
Description
I'm using the Accept: application/vnd.ipld.block feature of the gateway in order to download a single block for a root of a file tree.
The initial issue I was having was with cache-enabled requests not being able to load blocks. Specifically, it was happening in Node.js' built in undici API.
response = await fetch('https://bafkreiffsgtnic7uebaeuaixgph3pmmq2ywglpylzwrswv5so7m23hyuny.ipfs.w3s.link/', {
headers: {Accept: 'application/vnd.ipld.raw'}
})
console.log(response.headers.get('Content-Type'))
console.log(await response.text())Running the above in chrome devtools yields application/vnd.ipld.car when running from chrome devtools, but yields text/plain; charset=ISO-8859-1 when in Node.js.
response = await fetch('https://bafkreiffsgtnic7uebaeuaixgph3pmmq2ywglpylzwrswv5so7m23hyuny.ipfs.w3s.link/', {
cache: 'no-cache',
headers: {Accept: 'application/vnd.ipld.raw'}
})
console.log(response.headers.get('Content-Type'))
console.log(await response.text())Setting the cache parameter to no-cache fixes it which leads me to think it's something to do with caching.
In Firefox, when I try to trigger the request from the devtools, it all works correctly, however when I do so with code I get a CORS error for the preflight request.
await fetch("https://w3s.link/ipfs/bafybeic3zi46caikdvukly7xwnjrecbvmllafvopvlyw6ylt3oeht7h5om/", {
"credentials": "omit",
"headers": {
"User-Agent": "Mozilla/5.0 (X11; Linux x86_64; rv:106.0) Gecko/20100101 Firefox/106.0",
"Accept": "*/*",
"Accept-Language": "en-US,en;q=0.5",
"Sec-Fetch-Dest": "empty",
"Sec-Fetch-Mode": "cors",
"Sec-Fetch-Site": "cross-site"
},
"referrer": "http://localhost:8000/",
"method": "OPTIONS",
"mode": "cors"
});Yields Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at https://w3s.link/ipfs/bafybeic3zi46caikdvukly7xwnjrecbvmllafvopvlyw6ylt3oeht7h5om/. (Reason: CORS header ‘Access-Control-Allow-Origin’ missing). Status code: 500. with the following response headers:
HTTP/2 500 Internal Server Error
date: Wed, 16 Nov 2022 21:17:53 GMT
content-type: text/html; charset=UTF-8
x-frame-options: SAMEORIGIN
referrer-policy: same-origin
cache-control: private, max-age=0, no-store, no-cache, must-revalidate, post-check=0, pre-check=0
expires: Thu, 01 Jan 1970 00:00:01 GMT
cf-ray: 76b3418b4f971a0f-EWR
server: cloudflare
X-Firefox-Spdy: h2
It feels like there might be something funky going on with CORS not being set? I'm a little stuck as to how I could work around this. 😅 It really looks like it's just preflight requests that aren't working.