reth_tracing/
layers.rs

1use crate::{formatter::LogFormat, LayerInfo, LogFilterReloadHandle};
2#[cfg(feature = "otlp-logs")]
3use reth_tracing_otlp::{log_layer, OtlpLogsConfig};
4#[cfg(feature = "otlp")]
5use reth_tracing_otlp::{span_layer, OtlpConfig};
6use rolling_file::{RollingConditionBasic, RollingFileAppender};
7use std::{
8    fmt,
9    path::{Path, PathBuf},
10};
11use tracing_appender::non_blocking::WorkerGuard;
12use tracing_subscriber::{filter::Directive, reload, EnvFilter, Layer, Registry};
13
14/// A worker guard returned by the file layer.
15///
16///  When a guard is dropped, all events currently in-memory are flushed to the log file this guard
17///  belongs to.
18pub type FileWorkerGuard = tracing_appender::non_blocking::WorkerGuard;
19
20///  A boxed tracing [Layer].
21pub(crate) type BoxedLayer<S> = Box<dyn Layer<S> + Send + Sync>;
22
23/// Default [directives](Directive) for [`EnvFilter`] which:
24/// 1. Disable high-frequency debug logs from dependencies such as `hyper`, `hickory-resolver`,
25///    `hickory_proto`, `discv5`, `jsonrpsee-server`, and `hyper_util::client::legacy::pool`.
26/// 2. Set `opentelemetry_*` crates log level to `WARN`, as `DEBUG` is too noisy.
27const DEFAULT_ENV_FILTER_DIRECTIVES: [&str; 9] = [
28    "hyper::proto::h1=off",
29    "hickory_resolver=off",
30    "hickory_proto=off",
31    "discv5=off",
32    "jsonrpsee-server=off",
33    "opentelemetry-otlp=warn",
34    "opentelemetry_sdk=warn",
35    "opentelemetry-http=warn",
36    "hyper_util::client::legacy::pool=off",
37];
38
39/// Manages the collection of layers for a tracing subscriber.
40///
41/// `Layers` acts as a container for different logging layers such as stdout, file, or journald.
42/// Each layer can be configured separately and then combined into a tracing subscriber.
43#[derive(Default)]
44pub struct Layers {
45    inner: Vec<BoxedLayer<Registry>>,
46}
47
48impl fmt::Debug for Layers {
49    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
50        f.debug_struct("Layers").field("layers_count", &self.inner.len()).finish()
51    }
52}
53
54impl Layers {
55    /// Creates a new `Layers` instance.
56    pub fn new() -> Self {
57        Self::default()
58    }
59
60    /// Adds a layer to the collection of layers.
61    pub fn add_layer<L>(&mut self, layer: L)
62    where
63        L: Layer<Registry> + Send + Sync,
64    {
65        self.inner.push(layer.boxed());
66    }
67
68    /// Consumes the `Layers` instance, returning the inner vector of layers.
69    pub(crate) fn into_inner(self) -> Vec<BoxedLayer<Registry>> {
70        self.inner
71    }
72
73    /// Adds a journald layer to the layers collection.
74    ///
75    /// # Arguments
76    /// * `filter` - A string containing additional filter directives for this layer.
77    ///
78    /// # Returns
79    /// An `eyre::Result<()>` indicating the success or failure of the operation.
80    pub(crate) fn journald(&mut self, filter: &str) -> eyre::Result<()> {
81        let journald_filter = build_env_filter(None, filter)?;
82        let layer = tracing_journald::layer()?.with_filter(journald_filter);
83        self.add_layer(layer);
84        Ok(())
85    }
86
87    /// Adds a stdout layer with specified formatting and filtering.
88    ///
89    /// # Arguments
90    /// * `format` - The log message format.
91    /// * `default_directive` - Directive for the default logging level.
92    /// * `filters` - Additional filter directives as a string.
93    /// * `color` - Optional color configuration for the log messages.
94    /// * `reloadable` - If true, wraps the filter in a reload layer so it can be changed at
95    ///   runtime, and returns the reload handle.
96    ///
97    /// # Returns
98    /// An `eyre::Result` with an optional [`LogFilterReloadHandle`] (present when `reloadable` is
99    /// true).
100    pub(crate) fn stdout(
101        &mut self,
102        format: LogFormat,
103        default_directive: Directive,
104        filters: &str,
105        color: Option<String>,
106        reloadable: bool,
107    ) -> eyre::Result<Option<LogFilterReloadHandle>> {
108        let filter = build_env_filter(Some(default_directive), filters)?;
109
110        // When reloadable, always show target since the user may switch to DEBUG/TRACE
111        // at runtime via RPC — freezing target=false at init would hide module paths.
112        // Otherwise, only show target when initial level is higher than INFO.
113        let show_target = reloadable ||
114            filter.max_level_hint().is_none_or(|max_level| max_level > tracing::Level::INFO);
115
116        if reloadable {
117            let (reloadable_filter, handle) = reload::Layer::new(filter);
118            let layer = format.apply(reloadable_filter, color, show_target, None);
119            self.add_layer(layer);
120            Ok(Some(handle))
121        } else {
122            let layer = format.apply(filter, color, show_target, None);
123            self.add_layer(layer);
124            Ok(None)
125        }
126    }
127
128    /// Adds a file logging layer to the layers collection.
129    ///
130    /// # Arguments
131    /// * `format` - The format for log messages.
132    /// * `filter` - Additional filter directives as a string.
133    /// * `file_info` - Information about the log file including path and rotation strategy.
134    /// * `reloadable` - If true, wraps the filter in a reload layer so it can be changed at
135    ///   runtime, and returns the reload handle.
136    ///
137    /// # Returns
138    /// An `eyre::Result` with the file worker guard and an optional [`LogFilterReloadHandle`]
139    /// (present when `reloadable` is true).
140    pub(crate) fn file(
141        &mut self,
142        format: LogFormat,
143        filter: &str,
144        file_info: FileInfo,
145        reloadable: bool,
146    ) -> eyre::Result<(FileWorkerGuard, Option<LogFilterReloadHandle>)> {
147        let (writer, guard) = file_info.create_log_writer()?;
148        let file_filter = build_env_filter(None, filter)?;
149
150        if reloadable {
151            let (reloadable_filter, handle) = reload::Layer::new(file_filter);
152            self.add_layer(format.apply(reloadable_filter, None, true, Some(writer)));
153            Ok((guard, Some(handle)))
154        } else {
155            self.add_layer(format.apply(file_filter, None, true, Some(writer)));
156            Ok((guard, None))
157        }
158    }
159
160    pub(crate) fn samply(&mut self, config: LayerInfo) -> eyre::Result<()> {
161        self.add_layer(
162            tracing_samply::SamplyLayer::new()
163                .map_err(|e| eyre::eyre!("Failed to create samply layer: {e}"))?
164                .with_filter(build_env_filter(
165                    Some(config.default_directive.parse()?),
166                    &config.filters,
167                )?),
168        );
169        Ok(())
170    }
171
172    #[cfg(feature = "tracy")]
173    pub(crate) fn tracy(&mut self, config: LayerInfo) -> eyre::Result<()> {
174        // Newtype wrapper around `DefaultFields` so that `FormattedFields<TracyFields>` uses a
175        // distinct extension key from the fmt layer's `FormattedFields<DefaultFields>`. Without
176        // this, when both layers are active the fmt layer may insert ANSI-colored fields first,
177        // and the Tracy layer reuses them — leaking escape codes into Tracy zone text.
178        struct TracyFields(tracing_subscriber::fmt::format::DefaultFields);
179        impl<'writer> tracing_subscriber::fmt::FormatFields<'writer> for TracyFields {
180            fn format_fields<R: tracing_subscriber::field::RecordFields>(
181                &self,
182                writer: tracing_subscriber::fmt::format::Writer<'writer>,
183                fields: R,
184            ) -> core::fmt::Result {
185                self.0.format_fields(writer, fields)
186            }
187        }
188
189        struct Config(TracyFields);
190        impl tracing_tracy::Config for Config {
191            type Formatter = TracyFields;
192            fn formatter(&self) -> &Self::Formatter {
193                &self.0
194            }
195            fn format_fields_in_zone_name(&self) -> bool {
196                false
197            }
198        }
199
200        self.add_layer(
201            tracing_tracy::TracyLayer::new(Config(TracyFields(Default::default()))).with_filter(
202                build_env_filter(Some(config.default_directive.parse()?), &config.filters)?,
203            ),
204        );
205        Ok(())
206    }
207
208    /// Add OTLP spans layer to the layer collection
209    #[cfg(feature = "otlp")]
210    pub fn with_span_layer(
211        &mut self,
212        otlp_config: OtlpConfig,
213        filter: EnvFilter,
214    ) -> eyre::Result<()> {
215        // Create the span provider
216
217        let span_layer = span_layer(otlp_config)
218            .map_err(|e| eyre::eyre!("Failed to build OTLP span exporter {}", e))?
219            .with_filter(filter);
220
221        self.add_layer(span_layer);
222
223        Ok(())
224    }
225
226    /// Add OTLP logs layer to the layer collection
227    #[cfg(feature = "otlp-logs")]
228    pub fn with_log_layer(
229        &mut self,
230        otlp_config: OtlpLogsConfig,
231        filter: EnvFilter,
232    ) -> eyre::Result<()> {
233        let log_layer = log_layer(otlp_config)
234            .map_err(|e| eyre::eyre!("Failed to build OTLP log exporter {}", e))?
235            .with_filter(filter);
236
237        self.add_layer(log_layer);
238
239        Ok(())
240    }
241}
242
243/// Holds configuration information for file logging.
244///
245/// Contains details about the log file's path, name, size, and rotation strategy.
246#[derive(Debug, Clone)]
247pub struct FileInfo {
248    dir: PathBuf,
249    file_name: String,
250    max_size_bytes: u64,
251    max_files: usize,
252}
253
254impl FileInfo {
255    /// Creates a new `FileInfo` instance.
256    pub const fn new(
257        dir: PathBuf,
258        file_name: String,
259        max_size_bytes: u64,
260        max_files: usize,
261    ) -> Self {
262        Self { dir, file_name, max_size_bytes, max_files }
263    }
264
265    /// Creates the log directory if it doesn't exist.
266    fn create_log_dir(&self) -> eyre::Result<&Path> {
267        let log_dir: &Path = self.dir.as_ref();
268        if !log_dir.exists() {
269            std::fs::create_dir_all(log_dir)
270                .map_err(|err| eyre::eyre!("Could not create log directory {log_dir:?}: {err}"))?;
271        }
272        Ok(log_dir)
273    }
274
275    /// Creates a non-blocking writer for the log file.
276    fn create_log_writer(
277        &self,
278    ) -> eyre::Result<(tracing_appender::non_blocking::NonBlocking, WorkerGuard)> {
279        let log_dir = self.create_log_dir()?;
280        let (writer, guard) = tracing_appender::non_blocking(
281            RollingFileAppender::new(
282                log_dir.join(&self.file_name),
283                RollingConditionBasic::new().max_size(self.max_size_bytes),
284                self.max_files,
285            )
286            .map_err(|err| eyre::eyre!("Could not initialize file logging: {err}"))?,
287        );
288        Ok((writer, guard))
289    }
290}
291
292/// Builds an environment filter for logging.
293///
294/// The events are filtered by `default_directive`, unless overridden by `RUST_LOG`.
295///
296/// # Arguments
297/// * `default_directive` - An optional `Directive` that sets the default directive.
298/// * `directives` - Additional directives as a comma-separated string.
299///
300/// # Returns
301/// An `eyre::Result<EnvFilter>` that can be used to configure a tracing subscriber.
302fn build_env_filter(
303    default_directive: Option<Directive>,
304    directives: &str,
305) -> eyre::Result<EnvFilter> {
306    let env_filter = if let Some(default_directive) = default_directive {
307        EnvFilter::builder().with_default_directive(default_directive).from_env_lossy()
308    } else {
309        EnvFilter::builder().from_env_lossy()
310    };
311
312    DEFAULT_ENV_FILTER_DIRECTIVES
313        .into_iter()
314        .chain(directives.split(',').filter(|d| !d.is_empty()))
315        .try_fold(env_filter, |env_filter, directive| {
316            Ok(env_filter.add_directive(directive.parse()?))
317        })
318}
reth_tracing/layers.rs

reth_tracing/
layers.rs
