Use env!("CARGO_CRATE_NAME") in the example to simplify the tracing setup code

[hongweipeng]

…etup code

Motivation

The example code is full of tracing registration codes, and the log level is hard-coded. I think it can be replaced with the module_path! macro.

Solution

Simplify the code.

[jplatte]

Interesting idea. Two suggestions:

• Use concat! instead of format!
• Use the crate name instead of the module path so this still applies the log level to the entire crate's logs if moved into a submodule

What do you think? I think together this would look like concat!(env!("CARGO_CRATE_NAME"), "=debug")).

[ttys3]

CARGO_CRATE_NAME is better.

and for concat , I do not think it is necessary. keep using format! is much clear.

[ttys3]

I'm afraid that concat!(env!("CARGO_CRATE_NAME"), "=debug,tower_http=debug") is much less clear compared to:

format!("{}=debug,tower_http=debug", env!("CARGO_CRATE_NAME"))

I do not believe there will be performance issues for our usage scenario.

[ttys3]

I'm afraid that concat!(env!("CARGO_CRATE_NAME"), "=debug,tower_http=debug") is much less clear compared to:

format!("{}=debug,tower_http=debug", env!("CARGO_CRATE_NAME"))

I do not believe there will be performance issues for our usage scenario.

[jplatte]

Yeah, it's a bit ugly. Feel free to change it back.

[mladedav]

Personally, I'd say having

let crate_name = env!("CARGO_CRATE_NAME");
format!("{crate_name}=debug,tower_http=debug")

would be a more readable alternative, but feel free to ignore this, either is fine.

[jplatte]

Thanks!