static handler brings problems

[ptxmac]

The CoAPServer::handle takes a 'static handler.

I'm a bit new to rust, but I believe this means we can only use top level methods as handler, and then all state needed for the server will need to be stored in global variables?

As far as I understand it, this will also make the routing tool in #4 impossible.

Please correct me if I'm wrong!

[Covertness]

@ptxmac I think this will be changed in #4 . The handler would be an instance of a struct that could store some variables. Just like this example.

[ptxmac]

I've looked a bit more on my problem. It looks like 'static isn't the problem. I would like to use a closure as a handler so I can capture some local state, but closures doesn't satisfy Copy.

I looked at the handle trait in Iron: https://github.com/iron/iron/blob/master/src/middleware/mod.rs#L58 and they managed to do it without Copy which allows this example to work: https://github.com/iron/iron/blob/master/examples/redirect.rs

[Covertness]

Copy isn't necessary in #4

[jamesmunns]

Yeah, I'm struggling with lifetimes as well. I've kind of hit a wall where I need to clone my "router" struct every time a function is dispatched (so it can be moved into the handler closure), or it needs to have static lifetime. I need to study how the iron handler works a little better.

I've thought about using box'd closures, but I haven't used those yet. You can see what I have here: https://github.com/Covertness/coap-rs/compare/master...jamesmunns:coap-router?expand=1 - but like I said, I hit a bit of a wall when I try to integrate the router (it works well on its own, but trying to get it to work interchangably with a 'static function handler is more difficult than I thought.

I'm open to any thoughts or suggestions.

[jamesmunns]

I believe this will help in the future: rust-lang/rust#34511

In the future, I would suggest that we use boxed closures rather than static handlers.

[Covertness]

handler has removed static #47