Connection doesn't offer any way to iterate its contents

[lilyball]

The Connection header lets me test if it contains specific "connection options"¹ are contained in it. But it doesn't let me actually iterate its contents to see what it contains.

This is very frustrating as I need to actually know what's in the header because I'm implementing a gateway and I need to strip the referenced header names from the request I'm proxying. I would really like to be able to use headers::Connection so I don't have to worry about parsing the comma-separated list myself.

In theory I could just parse the header and then walk the whole headers map and compare each entry to the Connection, except HeaderMap does not offer a retain() operation and so that approach would require reallocating the whole map even if I don't end up making any changes.

Footnotes

1. This is represented as a private impl AsConnectionOption type, which means it's undocumented. Really that should be changed so AsConnectionOption is public and simply inherits from a sealed trait, so the generated docs will at least tell me what implements it. Or maybe change it to use impl AsRef<str> instead, or even impl AsRef<[u8]> as that supports the required comparison too. ↩

[seanmonstar]

We could come up with an fn iter(&self) -> impl Iterator (what would the items be? &str?). Would you like to propose that and send a PR?

which means it's undocumented. Really that should be changed

But it's not undocumented, the documentation for the contains method lists exactly what types can be passed. So, I don't think it will be changed.

This is very frustrating

Is it frustrating? If so, I'm sorry about that. However, a missing function shouldn't typically be frustrating. It's just something that would be nice to add. I'd recommend trying to frame feature requests in a positive way.