http status 404

[ameknite]

Can someone explain me why when I try to get the header of a crate page, it gives me HTTP/2 404
Is this a bug?

example:
curl -I https://crates.io/crates/rand
gives you:

HTTP/2 404 
content-length: 0
server: Cowboy
report-to: {"group":"heroku-nel","max_age":3600,"endpoints":[{"url":"https://nel.heroku.com/reports?ts=1710550532&sid=af571f24-03ee-46d1-9f90-ab9030c2c74c&s=494ZKz8htAtYLT%2Bl9FGg7rswx3Bpw7WmWdxkk0p8yJM%3D"}]}
reporting-endpoints: heroku-nel=https://nel.heroku.com/reports?ts=1710550532&sid=af571f24-03ee-46d1-9f90-ab9030c2c74c&s=494ZKz8htAtYLT%2Bl9FGg7rswx3Bpw7WmWdxkk0p8yJM%3D
nel: {"report_to":"heroku-nel","max_age":3600,"success_fraction":0.005,"failure_fraction":0.05,"response_headers":["Via"]}
access-control-allow-origin: *
strict-transport-security: max-age=31536000; includeSubDomains
date: Sat, 16 Mar 2024 00:55:32 GMT
via: 1.1 vegur, 1.1 f1c5a27e35ac834b32534347282b3496.cloudfront.net (CloudFront)
x-cache: Error from cloudfront
x-amz-cf-pop: DFW55-C1
x-amz-cf-id: Lr0sdRMwYLw_lRqhm7Wv9wZTv1FxaSplOKfa1zQaITFl6U3jZXHDrQ==

[LawnGnome]

Is this a bug?

This is intentional.

The crates.io frontend is implemented using Ember.js, so there's no backend route that returns the HTML that you see for, say, https://crates.io/crates/rand. What happens instead is that requests with Accept: text/html (such as any request your browser would send) is intercepted within the crates.io backend by this middleware, which then serves up the Ember.js bundle. Requests that don't have that Accept header (like this curl command) get a 404 instead, as you saw.

I'm guessing that what you're probably more interested instead is the crates.io API — in your example, https://crates.io/api/v1/crates/rand probably has the data you're looking for. crates.io implements a superset of the cargo registry web API, so those docs are a good place to start to see what's available.