Hi,
I’m struggling to figure out why I am unable to make XMLHttpRequests to a domain when I click the Cloud icon in the DNS settings to put the domain behind the Cloudflare proxy. The strange thing is I can only replicate the issue in Google Chrome - FireFox works fine.
If I disable the CF proxy, then Google Chrome is then able to load the website.
When viewing in chrome…
From the server’s logs, I can see that only the OPTIONS requests are hitting the server. The GET requests are then failing with the three different errors in chrome (listed in order of presentation):
- ERR_HTTP2_PROTOCOL_ERROR (x8)
- ERR_FAILED (x10)
- ERR_CONNECTION_CLOSED (all remaining requests)
Viewing the page being requested via the XMLHttpRequest shows the page fine in Chrome.
Running CURL to dump the headers, I get the following response while the domain is operating behind the CF proxy:
curl --dump-header - -o /dev/null https://my-domain-behind-cf.com/path-to-api-endpoint -H "Origin: https://my-test-domain.test" -H "X-Requested-With: XMLHttpRequest"
date: Tue, 05 Sep 2023 10:37:37 GMT
content-type: application/json
vary: Accept-Encoding
vary: Origin
cache-control: no-cache, private
access-control-allow-origin: https://my-test-domain.test
access-control-allow-credentials: true
set-cookie: <redacted> httponly
x-frame-options: SAMEORIGIN
x-xss-protection: 1; mode=block
x-content-type-options: nosniff
x-phil-test: hello world
cf-cache-status: DYNAMIC
report-to: {"endpoints":[{"url":"https:\/\/a.nel.cloudflare.com\/report\/v3?s=Ta%2Fb6opEOvN%2BuChXALjOHELLXf%2B7zoV3cSGfhgYryqE%2F2ea0TOrR5xo3jdFgrvx6mlveccCQu2V0YGYHoYPbD8z30G8Z6AyHTHx3mQwml0ku4DWsEyC858Q9z89H%2FoBRxVesGEDVLLD%2FKZ4EGJcE"}],"group":"cf-nel","max_age":604800}
nel: {"success_fraction":0,"report_to":"cf-nel","max_age":604800}
server: cloudflare
cf-ray: 801dd68478602dd9-MAN
Caching is not enabled in Cloudflare for the domain being requested however this is the end goal.
Thank you in advance
