mqtt_protocol_core/logger.rs
1/**
2 * MIT License
3 *
4 * Copyright (c) 2025 Takatoshi Kondo
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in all
14 * copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22 * SOFTWARE.
23 */
24use once_cell::sync::OnceCell;
25use tracing::Level;
26use tracing_subscriber::{fmt, EnvFilter};
27
28static LOGGER: OnceCell<()> = OnceCell::new();
29
30pub fn init(default_level: Level) {
31 LOGGER.get_or_init(|| {
32 let env_filter = EnvFilter::try_from_default_env()
33 .unwrap_or_else(|_| EnvFilter::from(default_level.to_string()));
34
35 fmt().with_env_filter(env_filter).with_target(true).init();
36 });
37}