Using the `time` crate to show time information

[lpotthast]

The .without_time() call mentioned in the readme is not strictly necessary.

The following setup allows timing information to be displayed by using the time crate using it's wasm-bindgen feature which enables wasm support.

In Cargo.toml, define the following dependencies:

time = { version = "0.3.23", features = ["wasm-bindgen"] }
tracing = "0.1.37"
tracing-subscriber = { version = "0.3.17", features = ["time", "local-time"] }
tracing-subscriber-wasm = "0.1.0"

And in your rust setup code, make use of the .with_timer function:

use tracing_subscriber::fmt::{fmt, time::LocalTime};
use tracing_subscriber_wasm::MakeConsoleWriter;

fmt()
        .with_writer(
            // To avoid trace events in the browser from showing their
            // JS backtrace, which is very annoying, in my opinion
            MakeConsoleWriter::default().map_trace_level_to(tracing::Level::DEBUG),
        )
        .with_timer(LocalTime::rfc_3339())
        .pretty()
        .init();

You can use different implementations. See

• https://docs.rs/tracing-subscriber/0.3.17/tracing_subscriber/fmt/struct.SubscriberBuilder.html#method.with_timer and
• https://docs.rs/tracing-subscriber/0.3.17/tracing_subscriber/fmt/time/index.html

for more information.

Example output:

2023-07-29T15:04:26.476999936+02:00  INFO simple::app: initialize <Test>
    at examples\simple\src\app.rs:25
    in leptos_dom::components::dyn_child::<DynChild />
    in leptos_dom::Fn() -> impl IntoView

[jquesada2016]

@lpotthast thanks for the info. I did know about this a bit after publishing the crate, but didn't think it was worth cutting a new release just for the readme. But if you think it's worth it, I'd welcome and be grateful for a pull request that adds a note, and I'll publish a new version.