// Copyright (C) Parity Technologies (UK) Ltd.
// This file is part of Substrate.
// SPDX-License-Identifier: GPL-3.0-or-later WITH Classpath-exception-2.0
// Substrate is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// Substrate is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with Substrate. If not, see <https://www.gnu.org/licenses/>.
use parking_lot::Mutex;
use std::sync::OnceLock;
use tracing_subscriber::{
filter::Directive, fmt as tracing_fmt, layer, reload::Handle, EnvFilter, Registry,
};
// Handle to reload the tracing log filter
static FILTER_RELOAD_HANDLE: OnceLock<Handle<EnvFilter, SCSubscriber>> = OnceLock::new();
// Directives that are defaulted to when resetting the log filter
static DEFAULT_DIRECTIVES: OnceLock<Mutex<Vec<String>>> = OnceLock::new();
// Current state of log filter
static CURRENT_DIRECTIVES: OnceLock<Mutex<Vec<String>>> = OnceLock::new();
/// Add log filter directive(s) to the defaults
///
/// The syntax is identical to the CLI `<target>=<level>`:
///
/// `sync=debug,state=trace`
pub(crate) fn add_default_directives(directives: &str) {
DEFAULT_DIRECTIVES
.get_or_init(|| Mutex::new(Vec::new()))
.lock()
.push(directives.to_owned());
add_directives(directives);
}
/// Add directives to current directives.
pub fn add_directives(directives: &str) {
CURRENT_DIRECTIVES
.get_or_init(|| Mutex::new(Vec::new()))
.lock()
.push(directives.to_owned());
}
/// Returns the current directives.
pub fn get_directives() -> Vec<String> {
CURRENT_DIRECTIVES.get_or_init(|| Mutex::new(Vec::new())).lock().clone()
}
/// Parse `Directive` and add to default directives if successful.
///
/// Ensures the supplied directive will be restored when resetting the log filter.
pub(crate) fn parse_default_directive(directive: &str) -> super::Result<Directive> {
let dir = directive.parse()?;
add_default_directives(directive);
Ok(dir)
}
/// Reload the logging filter with the supplied directives added to the existing directives
pub fn reload_filter() -> Result<(), String> {
let mut env_filter = EnvFilter::default();
if let Some(current_directives) = CURRENT_DIRECTIVES.get() {
// Use join and then split in case any directives added together
for directive in current_directives.lock().join(",").split(',').map(|d| d.parse()) {
match directive {
Ok(dir) => env_filter = env_filter.add_directive(dir),
Err(invalid_directive) => {
log::warn!(
target: "tracing",
"Unable to parse directive while setting log filter: {:?}",
invalid_directive,
);
},
}
}
}
// Set the max logging level for the `log` macros.
let max_level_hint =
tracing_subscriber::Layer::<tracing_subscriber::FmtSubscriber>::max_level_hint(&env_filter);
log::set_max_level(super::to_log_level_filter(max_level_hint));
log::debug!(target: "tracing", "Reloading log filter with: {}", env_filter);
FILTER_RELOAD_HANDLE
.get()
.ok_or("No reload handle present")?
.reload(env_filter)
.map_err(|e| format!("{}", e))
}
/// Resets the log filter back to the original state when the node was started.
///
/// Includes substrate defaults and CLI supplied directives.
pub fn reset_log_filter() -> Result<(), String> {
let directive = DEFAULT_DIRECTIVES.get_or_init(|| Mutex::new(Vec::new())).lock().clone();
*CURRENT_DIRECTIVES.get_or_init(|| Mutex::new(Vec::new())).lock() = directive;
reload_filter()
}
/// Initialize FILTER_RELOAD_HANDLE, only possible once
pub(crate) fn set_reload_handle(handle: Handle<EnvFilter, SCSubscriber>) {
let _ = FILTER_RELOAD_HANDLE.set(handle);
}
// The layered Subscriber as built up in `LoggerBuilder::init()`.
// Used in the reload `Handle`.
type SCSubscriber<
N = tracing_fmt::format::DefaultFields,
E = crate::logging::EventFormat,
W = crate::logging::DefaultLogger,
> = layer::Layered<tracing_fmt::Layer<Registry, N, E, W>, Registry>;