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//! A rolling file appender.
//!
//! Creates a new log file at a fixed frequency as defined by [`Rotation`][self::Rotation].
//! Logs will be written to this file for the duration of the period and will automatically roll over
//! to the newly created log file once the time period has elapsed.
//!
//! The log file is created at the specified directory and file name prefix which *may* be appended with
//! the date and time.
//!
//! The following helpers are available for creating a rolling file appender.
//!
//! - [`Rotation::minutely()`][minutely]: A new log file in the format of `some_directory/log_file_name_prefix.yyyy-MM-dd-HH-mm`
//! will be created minutely (once per minute)
//! - [`Rotation::hourly()`][hourly]: A new log file in the format of `some_directory/log_file_name_prefix.yyyy-MM-dd-HH`
//! will be created hourly
//! - [`Rotation::daily()`][daily]: A new log file in the format of `some_directory/log_file_name_prefix.yyyy-MM-dd`
//! will be created daily
//! - [`Rotation::never()`][never()]: This will result in log file located at `some_directory/log_file_name`
//!
//!
//! # Examples
//!
//! ```rust
//! # fn docs() {
//! use tracing_appender::rolling::{RollingFileAppender, Rotation};
//! let file_appender = RollingFileAppender::new(Rotation::HOURLY, "/some/directory", "prefix.log");
//! # }
//! ```
use crate::sync::{RwLock, RwLockReadGuard};
use std::{
fmt::{self, Debug},
fs::{self, File, OpenOptions},
io::{self, Write},
path::{Path, PathBuf},
sync::atomic::{AtomicUsize, Ordering},
};
use time::{format_description, Date, Duration, OffsetDateTime, Time};
mod builder;
pub use builder::{Builder, InitError};
/// A file appender with the ability to rotate log files at a fixed schedule.
///
/// `RollingFileAppender` implements the [`std:io::Write` trait][write] and will
/// block on write operations. It may be used with [`NonBlocking`] to perform
/// writes without blocking the current thread.
///
/// Additionally, `RollingFileAppender` also implements the [`MakeWriter`]
/// trait from `tracing-subscriber`, so it may also be used
/// directly, without [`NonBlocking`].
///
/// [write]: std::io::Write
/// [`NonBlocking`]: super::non_blocking::NonBlocking
///
/// # Examples
///
/// Rolling a log file once every hour:
///
/// ```rust
/// # fn docs() {
/// let file_appender = tracing_appender::rolling::hourly("/some/directory", "prefix");
/// # }
/// ```
///
/// Combining a `RollingFileAppender` with another [`MakeWriter`] implementation:
///
/// ```rust
/// # fn docs() {
/// use tracing_subscriber::fmt::writer::MakeWriterExt;
///
/// // Log all events to a rolling log file.
/// let logfile = tracing_appender::rolling::hourly("/logs", "myapp-logs");
/// // Log `INFO` and above to stdout.
/// let stdout = std::io::stdout.with_max_level(tracing::Level::INFO);
///
/// tracing_subscriber::fmt()
/// // Combine the stdout and log file `MakeWriter`s into one
/// // `MakeWriter` that writes to both
/// .with_writer(stdout.and(logfile))
/// .init();
/// # }
/// ```
///
/// [`MakeWriter`]: tracing_subscriber::fmt::writer::MakeWriter
pub struct RollingFileAppender {
state: Inner,
writer: RwLock<File>,
#[cfg(test)]
now: Box<dyn Fn() -> OffsetDateTime + Send + Sync>,
}
/// A [writer] that writes to a rolling log file.
///
/// This is returned by the [`MakeWriter`] implementation for [`RollingFileAppender`].
///
/// [writer]: std::io::Write
/// [`MakeWriter`]: tracing_subscriber::fmt::writer::MakeWriter
#[derive(Debug)]
pub struct RollingWriter<'a>(RwLockReadGuard<'a, File>);
#[derive(Debug)]
struct Inner {
log_directory: PathBuf,
log_filename_prefix: Option<String>,
log_filename_suffix: Option<String>,
date_format: Vec<format_description::FormatItem<'static>>,
rotation: Rotation,
next_date: AtomicUsize,
max_files: Option<usize>,
}
// === impl RollingFileAppender ===
impl RollingFileAppender {
/// Creates a new `RollingFileAppender`.
///
/// A `RollingFileAppender` will have a fixed rotation whose frequency is
/// defined by [`Rotation`][self::Rotation]. The `directory` and
/// `file_name_prefix` arguments determine the location and file name's _prefix_
/// of the log file. `RollingFileAppender` will automatically append the current date
/// and hour (UTC format) to the file name.
///
/// Alternatively, a `RollingFileAppender` can be constructed using one of the following helpers:
///
/// - [`Rotation::minutely()`][minutely],
/// - [`Rotation::hourly()`][hourly],
/// - [`Rotation::daily()`][daily],
/// - [`Rotation::never()`][never()]
///
/// Additional parameters can be configured using [`RollingFileAppender::builder`].
///
/// # Examples
///
/// ```rust
/// # fn docs() {
/// use tracing_appender::rolling::{RollingFileAppender, Rotation};
/// let file_appender = RollingFileAppender::new(Rotation::HOURLY, "/some/directory", "prefix.log");
/// # }
/// ```
pub fn new(
rotation: Rotation,
directory: impl AsRef<Path>,
filename_prefix: impl AsRef<Path>,
) -> RollingFileAppender {
let filename_prefix = filename_prefix
.as_ref()
.to_str()
.expect("filename prefix must be a valid UTF-8 string");
Self::builder()
.rotation(rotation)
.filename_prefix(filename_prefix)
.build(directory)
.expect("initializing rolling file appender failed")
}
/// Returns a new [`Builder`] for configuring a `RollingFileAppender`.
///
/// The builder interface can be used to set additional configuration
/// parameters when constructing a new appender.
///
/// Unlike [`RollingFileAppender::new`], the [`Builder::build`] method
/// returns a `Result` rather than panicking when the appender cannot be
/// initialized. Therefore, the builder interface can also be used when
/// appender initialization errors should be handled gracefully.
///
/// # Examples
///
/// ```rust
/// # fn docs() {
/// use tracing_appender::rolling::{RollingFileAppender, Rotation};
///
/// let file_appender = RollingFileAppender::builder()
/// .rotation(Rotation::HOURLY) // rotate log files once every hour
/// .filename_prefix("myapp") // log file names will be prefixed with `myapp.`
/// .filename_suffix("log") // log file names will be suffixed with `.log`
/// .build("/var/log") // try to build an appender that stores log files in `/var/log`
/// .expect("initializing rolling file appender failed");
/// # drop(file_appender);
/// # }
/// ```
#[must_use]
pub fn builder() -> Builder {
Builder::new()
}
fn from_builder(builder: &Builder, directory: impl AsRef<Path>) -> Result<Self, InitError> {
let Builder {
ref rotation,
ref prefix,
ref suffix,
ref max_files,
} = builder;
let directory = directory.as_ref().to_path_buf();
let now = OffsetDateTime::now_utc();
let (state, writer) = Inner::new(
now,
rotation.clone(),
directory,
prefix.clone(),
suffix.clone(),
*max_files,
)?;
Ok(Self {
state,
writer,
#[cfg(test)]
now: Box::new(OffsetDateTime::now_utc),
})
}
#[inline]
fn now(&self) -> OffsetDateTime {
#[cfg(test)]
return (self.now)();
#[cfg(not(test))]
OffsetDateTime::now_utc()
}
}
impl io::Write for RollingFileAppender {
fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
let now = self.now();
let writer = self.writer.get_mut();
if let Some(current_time) = self.state.should_rollover(now) {
let _did_cas = self.state.advance_date(now, current_time);
debug_assert!(_did_cas, "if we have &mut access to the appender, no other thread can have advanced the timestamp...");
self.state.refresh_writer(now, writer);
}
writer.write(buf)
}
fn flush(&mut self) -> io::Result<()> {
self.writer.get_mut().flush()
}
}
impl<'a> tracing_subscriber::fmt::writer::MakeWriter<'a> for RollingFileAppender {
type Writer = RollingWriter<'a>;
fn make_writer(&'a self) -> Self::Writer {
let now = self.now();
// Should we try to roll over the log file?
if let Some(current_time) = self.state.should_rollover(now) {
// Did we get the right to lock the file? If not, another thread
// did it and we can just make a writer.
if self.state.advance_date(now, current_time) {
self.state.refresh_writer(now, &mut self.writer.write());
}
}
RollingWriter(self.writer.read())
}
}
impl fmt::Debug for RollingFileAppender {
// This manual impl is required because of the `now` field (only present
// with `cfg(test)`), which is not `Debug`...
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_struct("RollingFileAppender")
.field("state", &self.state)
.field("writer", &self.writer)
.finish()
}
}
/// Creates a minutely-rotating file appender. This will rotate the log file once per minute.
///
/// The appender returned by `rolling::minutely` can be used with `non_blocking` to create
/// a non-blocking, minutely file appender.
///
/// The directory of the log file is specified with the `directory` argument.
/// `file_name_prefix` specifies the _prefix_ of the log file. `RollingFileAppender`
/// adds the current date, hour, and minute to the log file in UTC.
///
/// # Examples
///
/// ``` rust
/// # #[clippy::allow(needless_doctest_main)]
/// fn main () {
/// # fn doc() {
/// let appender = tracing_appender::rolling::minutely("/some/path", "rolling.log");
/// let (non_blocking_appender, _guard) = tracing_appender::non_blocking(appender);
///
/// let subscriber = tracing_subscriber::fmt().with_writer(non_blocking_appender);
///
/// tracing::subscriber::with_default(subscriber.finish(), || {
/// tracing::event!(tracing::Level::INFO, "Hello");
/// });
/// # }
/// }
/// ```
///
/// This will result in a log file located at `/some/path/rolling.log.yyyy-MM-dd-HH-mm`.
pub fn minutely(
directory: impl AsRef<Path>,
file_name_prefix: impl AsRef<Path>,
) -> RollingFileAppender {
RollingFileAppender::new(Rotation::MINUTELY, directory, file_name_prefix)
}
/// Creates an hourly-rotating file appender.
///
/// The appender returned by `rolling::hourly` can be used with `non_blocking` to create
/// a non-blocking, hourly file appender.
///
/// The directory of the log file is specified with the `directory` argument.
/// `file_name_prefix` specifies the _prefix_ of the log file. `RollingFileAppender`
/// adds the current date and hour to the log file in UTC.
///
/// # Examples
///
/// ``` rust
/// # #[clippy::allow(needless_doctest_main)]
/// fn main () {
/// # fn doc() {
/// let appender = tracing_appender::rolling::hourly("/some/path", "rolling.log");
/// let (non_blocking_appender, _guard) = tracing_appender::non_blocking(appender);
///
/// let subscriber = tracing_subscriber::fmt().with_writer(non_blocking_appender);
///
/// tracing::subscriber::with_default(subscriber.finish(), || {
/// tracing::event!(tracing::Level::INFO, "Hello");
/// });
/// # }
/// }
/// ```
///
/// This will result in a log file located at `/some/path/rolling.log.yyyy-MM-dd-HH`.
pub fn hourly(
directory: impl AsRef<Path>,
file_name_prefix: impl AsRef<Path>,
) -> RollingFileAppender {
RollingFileAppender::new(Rotation::HOURLY, directory, file_name_prefix)
}
/// Creates a daily-rotating file appender.
///
/// The appender returned by `rolling::daily` can be used with `non_blocking` to create
/// a non-blocking, daily file appender.
///
/// A `RollingFileAppender` has a fixed rotation whose frequency is
/// defined by [`Rotation`][self::Rotation]. The `directory` and
/// `file_name_prefix` arguments determine the location and file name's _prefix_
/// of the log file. `RollingFileAppender` automatically appends the current date in UTC.
///
/// # Examples
///
/// ``` rust
/// # #[clippy::allow(needless_doctest_main)]
/// fn main () {
/// # fn doc() {
/// let appender = tracing_appender::rolling::daily("/some/path", "rolling.log");
/// let (non_blocking_appender, _guard) = tracing_appender::non_blocking(appender);
///
/// let subscriber = tracing_subscriber::fmt().with_writer(non_blocking_appender);
///
/// tracing::subscriber::with_default(subscriber.finish(), || {
/// tracing::event!(tracing::Level::INFO, "Hello");
/// });
/// # }
/// }
/// ```
///
/// This will result in a log file located at `/some/path/rolling.log.yyyy-MM-dd-HH`.
pub fn daily(
directory: impl AsRef<Path>,
file_name_prefix: impl AsRef<Path>,
) -> RollingFileAppender {
RollingFileAppender::new(Rotation::DAILY, directory, file_name_prefix)
}
/// Creates a non-rolling file appender.
///
/// The appender returned by `rolling::never` can be used with `non_blocking` to create
/// a non-blocking, non-rotating appender.
///
/// The location of the log file will be specified the `directory` passed in.
/// `file_name` specifies the complete name of the log file (no date or time is appended).
///
/// # Examples
///
/// ``` rust
/// # #[clippy::allow(needless_doctest_main)]
/// fn main () {
/// # fn doc() {
/// let appender = tracing_appender::rolling::never("/some/path", "non-rolling.log");
/// let (non_blocking_appender, _guard) = tracing_appender::non_blocking(appender);
///
/// let subscriber = tracing_subscriber::fmt().with_writer(non_blocking_appender);
///
/// tracing::subscriber::with_default(subscriber.finish(), || {
/// tracing::event!(tracing::Level::INFO, "Hello");
/// });
/// # }
/// }
/// ```
///
/// This will result in a log file located at `/some/path/non-rolling.log`.
pub fn never(directory: impl AsRef<Path>, file_name: impl AsRef<Path>) -> RollingFileAppender {
RollingFileAppender::new(Rotation::NEVER, directory, file_name)
}
/// Defines a fixed period for rolling of a log file.
///
/// To use a `Rotation`, pick one of the following options:
///
/// ### Minutely Rotation
/// ```rust
/// # fn docs() {
/// use tracing_appender::rolling::Rotation;
/// let rotation = tracing_appender::rolling::Rotation::MINUTELY;
/// # }
/// ```
///
/// ### Hourly Rotation
/// ```rust
/// # fn docs() {
/// use tracing_appender::rolling::Rotation;
/// let rotation = tracing_appender::rolling::Rotation::HOURLY;
/// # }
/// ```
///
/// ### Daily Rotation
/// ```rust
/// # fn docs() {
/// use tracing_appender::rolling::Rotation;
/// let rotation = tracing_appender::rolling::Rotation::DAILY;
/// # }
/// ```
///
/// ### No Rotation
/// ```rust
/// # fn docs() {
/// use tracing_appender::rolling::Rotation;
/// let rotation = tracing_appender::rolling::Rotation::NEVER;
/// # }
/// ```
#[derive(Clone, Eq, PartialEq, Debug)]
pub struct Rotation(RotationKind);
#[derive(Clone, Eq, PartialEq, Debug)]
enum RotationKind {
Minutely,
Hourly,
Daily,
Never,
}
impl Rotation {
/// Provides an minutely rotation
pub const MINUTELY: Self = Self(RotationKind::Minutely);
/// Provides an hourly rotation
pub const HOURLY: Self = Self(RotationKind::Hourly);
/// Provides a daily rotation
pub const DAILY: Self = Self(RotationKind::Daily);
/// Provides a rotation that never rotates.
pub const NEVER: Self = Self(RotationKind::Never);
pub(crate) fn next_date(&self, current_date: &OffsetDateTime) -> Option<OffsetDateTime> {
let unrounded_next_date = match *self {
Rotation::MINUTELY => *current_date + Duration::minutes(1),
Rotation::HOURLY => *current_date + Duration::hours(1),
Rotation::DAILY => *current_date + Duration::days(1),
Rotation::NEVER => return None,
};
Some(self.round_date(&unrounded_next_date))
}
// note that this method will panic if passed a `Rotation::NEVER`.
pub(crate) fn round_date(&self, date: &OffsetDateTime) -> OffsetDateTime {
match *self {
Rotation::MINUTELY => {
let time = Time::from_hms(date.hour(), date.minute(), 0)
.expect("Invalid time; this is a bug in tracing-appender");
date.replace_time(time)
}
Rotation::HOURLY => {
let time = Time::from_hms(date.hour(), 0, 0)
.expect("Invalid time; this is a bug in tracing-appender");
date.replace_time(time)
}
Rotation::DAILY => {
let time = Time::from_hms(0, 0, 0)
.expect("Invalid time; this is a bug in tracing-appender");
date.replace_time(time)
}
// Rotation::NEVER is impossible to round.
Rotation::NEVER => {
unreachable!("Rotation::NEVER is impossible to round.")
}
}
}
fn date_format(&self) -> Vec<format_description::FormatItem<'static>> {
match *self {
Rotation::MINUTELY => format_description::parse("[year]-[month]-[day]-[hour]-[minute]"),
Rotation::HOURLY => format_description::parse("[year]-[month]-[day]-[hour]"),
Rotation::DAILY => format_description::parse("[year]-[month]-[day]"),
Rotation::NEVER => format_description::parse("[year]-[month]-[day]"),
}
.expect("Unable to create a formatter; this is a bug in tracing-appender")
}
}
// === impl RollingWriter ===
impl io::Write for RollingWriter<'_> {
fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
(&*self.0).write(buf)
}
fn flush(&mut self) -> io::Result<()> {
(&*self.0).flush()
}
}
// === impl Inner ===
impl Inner {
fn new(
now: OffsetDateTime,
rotation: Rotation,
directory: impl AsRef<Path>,
log_filename_prefix: Option<String>,
log_filename_suffix: Option<String>,
max_files: Option<usize>,
) -> Result<(Self, RwLock<File>), builder::InitError> {
let log_directory = directory.as_ref().to_path_buf();
let date_format = rotation.date_format();
let next_date = rotation.next_date(&now);
let inner = Inner {
log_directory,
log_filename_prefix,
log_filename_suffix,
date_format,
next_date: AtomicUsize::new(
next_date
.map(|date| date.unix_timestamp() as usize)
.unwrap_or(0),
),
rotation,
max_files,
};
let filename = inner.join_date(&now);
let writer = RwLock::new(create_writer(inner.log_directory.as_ref(), &filename)?);
Ok((inner, writer))
}
pub(crate) fn join_date(&self, date: &OffsetDateTime) -> String {
let date = date
.format(&self.date_format)
.expect("Unable to format OffsetDateTime; this is a bug in tracing-appender");
match (
&self.rotation,
&self.log_filename_prefix,
&self.log_filename_suffix,
) {
(&Rotation::NEVER, Some(filename), None) => filename.to_string(),
(&Rotation::NEVER, Some(filename), Some(suffix)) => format!("{}.{}", filename, suffix),
(&Rotation::NEVER, None, Some(suffix)) => suffix.to_string(),
(_, Some(filename), Some(suffix)) => format!("{}.{}.{}", filename, date, suffix),
(_, Some(filename), None) => format!("{}.{}", filename, date),
(_, None, Some(suffix)) => format!("{}.{}", date, suffix),
(_, None, None) => date,
}
}
fn prune_old_logs(&self, max_files: usize) {
let files = fs::read_dir(&self.log_directory).map(|dir| {
dir.filter_map(|entry| {
let entry = entry.ok()?;
let metadata = entry.metadata().ok()?;
// the appender only creates files, not directories or symlinks,
// so we should never delete a dir or symlink.
if !metadata.is_file() {
return None;
}
let filename = entry.file_name();
// if the filename is not a UTF-8 string, skip it.
let filename = filename.to_str()?;
if let Some(prefix) = &self.log_filename_prefix {
if !filename.starts_with(prefix) {
return None;
}
}
if let Some(suffix) = &self.log_filename_suffix {
if !filename.ends_with(suffix) {
return None;
}
}
if self.log_filename_prefix.is_none()
&& self.log_filename_suffix.is_none()
&& Date::parse(filename, &self.date_format).is_err()
{
return None;
}
let created = metadata.created().ok()?;
Some((entry, created))
})
.collect::<Vec<_>>()
});
let mut files = match files {
Ok(files) => files,
Err(error) => {
eprintln!("Error reading the log directory/files: {}", error);
return;
}
};
if files.len() < max_files {
return;
}
// sort the files by their creation timestamps.
files.sort_by_key(|(_, created_at)| *created_at);
// delete files, so that (n-1) files remain, because we will create another log file
for (file, _) in files.iter().take(files.len() - (max_files - 1)) {
if let Err(error) = fs::remove_file(file.path()) {
eprintln!(
"Failed to remove old log file {}: {}",
file.path().display(),
error
);
}
}
}
fn refresh_writer(&self, now: OffsetDateTime, file: &mut File) {
let filename = self.join_date(&now);
if let Some(max_files) = self.max_files {
self.prune_old_logs(max_files);
}
match create_writer(&self.log_directory, &filename) {
Ok(new_file) => {
if let Err(err) = file.flush() {
eprintln!("Couldn't flush previous writer: {}", err);
}
*file = new_file;
}
Err(err) => eprintln!("Couldn't create writer for logs: {}", err),
}
}
/// Checks whether or not it's time to roll over the log file.
///
/// Rather than returning a `bool`, this returns the current value of
/// `next_date` so that we can perform a `compare_exchange` operation with
/// that value when setting the next rollover time.
///
/// If this method returns `Some`, we should roll to a new log file.
/// Otherwise, if this returns we should not rotate the log file.
fn should_rollover(&self, date: OffsetDateTime) -> Option<usize> {
let next_date = self.next_date.load(Ordering::Acquire);
// if the next date is 0, this appender *never* rotates log files.
if next_date == 0 {
return None;
}
if date.unix_timestamp() as usize >= next_date {
return Some(next_date);
}
None
}
fn advance_date(&self, now: OffsetDateTime, current: usize) -> bool {
let next_date = self
.rotation
.next_date(&now)
.map(|date| date.unix_timestamp() as usize)
.unwrap_or(0);
self.next_date
.compare_exchange(current, next_date, Ordering::AcqRel, Ordering::Acquire)
.is_ok()
}
}
fn create_writer(directory: &Path, filename: &str) -> Result<File, InitError> {
let path = directory.join(filename);
let mut open_options = OpenOptions::new();
open_options.append(true).create(true);
let new_file = open_options.open(path.as_path());
if new_file.is_err() {
if let Some(parent) = path.parent() {
fs::create_dir_all(parent).map_err(InitError::ctx("failed to create log directory"))?;
return open_options
.open(path)
.map_err(InitError::ctx("failed to create initial log file"));
}
}
new_file.map_err(InitError::ctx("failed to create initial log file"))
}
#[cfg(test)]
mod test {
use super::*;
use std::fs;
use std::io::Write;
fn find_str_in_log(dir_path: &Path, expected_value: &str) -> bool {
let dir_contents = fs::read_dir(dir_path).expect("Failed to read directory");
for entry in dir_contents {
let path = entry.expect("Expected dir entry").path();
let file = fs::read_to_string(&path).expect("Failed to read file");
println!("path={}\nfile={:?}", path.display(), file);
if file.as_str() == expected_value {
return true;
}
}
false
}
fn write_to_log(appender: &mut RollingFileAppender, msg: &str) {
appender
.write_all(msg.as_bytes())
.expect("Failed to write to appender");
appender.flush().expect("Failed to flush!");
}
fn test_appender(rotation: Rotation, file_prefix: &str) {
let directory = tempfile::tempdir().expect("failed to create tempdir");
let mut appender = RollingFileAppender::new(rotation, directory.path(), file_prefix);
let expected_value = "Hello";
write_to_log(&mut appender, expected_value);
assert!(find_str_in_log(directory.path(), expected_value));
directory
.close()
.expect("Failed to explicitly close TempDir. TempDir should delete once out of scope.")
}
#[test]
fn write_minutely_log() {
test_appender(Rotation::HOURLY, "minutely.log");
}
#[test]
fn write_hourly_log() {
test_appender(Rotation::HOURLY, "hourly.log");
}
#[test]
fn write_daily_log() {
test_appender(Rotation::DAILY, "daily.log");
}
#[test]
fn write_never_log() {
test_appender(Rotation::NEVER, "never.log");
}
#[test]
fn test_rotations() {
// per-minute basis
let now = OffsetDateTime::now_utc();
let next = Rotation::MINUTELY.next_date(&now).unwrap();
assert_eq!((now + Duration::MINUTE).minute(), next.minute());
// per-hour basis
let now = OffsetDateTime::now_utc();
let next = Rotation::HOURLY.next_date(&now).unwrap();
assert_eq!((now + Duration::HOUR).hour(), next.hour());
// daily-basis
let now = OffsetDateTime::now_utc();
let next = Rotation::DAILY.next_date(&now).unwrap();
assert_eq!((now + Duration::DAY).day(), next.day());
// never
let now = OffsetDateTime::now_utc();
let next = Rotation::NEVER.next_date(&now);
assert!(next.is_none());
}
#[test]
#[should_panic(
expected = "internal error: entered unreachable code: Rotation::NEVER is impossible to round."
)]
fn test_never_date_rounding() {
let now = OffsetDateTime::now_utc();
let _ = Rotation::NEVER.round_date(&now);
}
#[test]
fn test_path_concatenation() {
let format = format_description::parse(
"[year]-[month]-[day] [hour]:[minute]:[second] [offset_hour \
sign:mandatory]:[offset_minute]:[offset_second]",
)
.unwrap();
let directory = tempfile::tempdir().expect("failed to create tempdir");
let now = OffsetDateTime::parse("2020-02-01 10:01:00 +00:00:00", &format).unwrap();
struct TestCase {
expected: &'static str,
rotation: Rotation,
prefix: Option<&'static str>,
suffix: Option<&'static str>,
}
let test = |TestCase {
expected,
rotation,
prefix,
suffix,
}| {
let (inner, _) = Inner::new(
now,
rotation.clone(),
directory.path(),
prefix.map(ToString::to_string),
suffix.map(ToString::to_string),
None,
)
.unwrap();
let path = inner.join_date(&now);
assert_eq!(
expected, path,
"rotation = {:?}, prefix = {:?}, suffix = {:?}",
rotation, prefix, suffix
);
};
let test_cases = vec![
// prefix only
TestCase {
expected: "app.log.2020-02-01-10-01",
rotation: Rotation::MINUTELY,
prefix: Some("app.log"),
suffix: None,
},
TestCase {
expected: "app.log.2020-02-01-10",
rotation: Rotation::HOURLY,
prefix: Some("app.log"),
suffix: None,
},
TestCase {
expected: "app.log.2020-02-01",
rotation: Rotation::DAILY,
prefix: Some("app.log"),
suffix: None,
},
TestCase {
expected: "app.log",
rotation: Rotation::NEVER,
prefix: Some("app.log"),
suffix: None,
},
// prefix and suffix
TestCase {
expected: "app.2020-02-01-10-01.log",
rotation: Rotation::MINUTELY,
prefix: Some("app"),
suffix: Some("log"),
},
TestCase {
expected: "app.2020-02-01-10.log",
rotation: Rotation::HOURLY,
prefix: Some("app"),
suffix: Some("log"),
},
TestCase {
expected: "app.2020-02-01.log",
rotation: Rotation::DAILY,
prefix: Some("app"),
suffix: Some("log"),
},
TestCase {
expected: "app.log",
rotation: Rotation::NEVER,
prefix: Some("app"),
suffix: Some("log"),
},
// suffix only
TestCase {
expected: "2020-02-01-10-01.log",
rotation: Rotation::MINUTELY,
prefix: None,
suffix: Some("log"),
},
TestCase {
expected: "2020-02-01-10.log",
rotation: Rotation::HOURLY,
prefix: None,
suffix: Some("log"),
},
TestCase {
expected: "2020-02-01.log",
rotation: Rotation::DAILY,
prefix: None,
suffix: Some("log"),
},
TestCase {
expected: "log",
rotation: Rotation::NEVER,
prefix: None,
suffix: Some("log"),
},
];
for test_case in test_cases {
test(test_case)
}
}
#[test]
fn test_make_writer() {
use std::sync::{Arc, Mutex};
use tracing_subscriber::prelude::*;
let format = format_description::parse(
"[year]-[month]-[day] [hour]:[minute]:[second] [offset_hour \
sign:mandatory]:[offset_minute]:[offset_second]",
)
.unwrap();
let now = OffsetDateTime::parse("2020-02-01 10:01:00 +00:00:00", &format).unwrap();
let directory = tempfile::tempdir().expect("failed to create tempdir");
let (state, writer) = Inner::new(
now,
Rotation::HOURLY,
directory.path(),
Some("test_make_writer".to_string()),
None,
None,
)
.unwrap();
let clock = Arc::new(Mutex::new(now));
let now = {
let clock = clock.clone();
Box::new(move || *clock.lock().unwrap())
};
let appender = RollingFileAppender { state, writer, now };
let default = tracing_subscriber::fmt()
.without_time()
.with_level(false)
.with_target(false)
.with_max_level(tracing_subscriber::filter::LevelFilter::TRACE)
.with_writer(appender)
.finish()
.set_default();
tracing::info!("file 1");
// advance time by one second
(*clock.lock().unwrap()) += Duration::seconds(1);
tracing::info!("file 1");
// advance time by one hour
(*clock.lock().unwrap()) += Duration::hours(1);
tracing::info!("file 2");
// advance time by one second
(*clock.lock().unwrap()) += Duration::seconds(1);
tracing::info!("file 2");
drop(default);
let dir_contents = fs::read_dir(directory.path()).expect("Failed to read directory");
println!("dir={:?}", dir_contents);
for entry in dir_contents {
println!("entry={:?}", entry);
let path = entry.expect("Expected dir entry").path();
let file = fs::read_to_string(&path).expect("Failed to read file");
println!("path={}\nfile={:?}", path.display(), file);
match path
.extension()
.expect("found a file without a date!")
.to_str()
.expect("extension should be UTF8")
{
"2020-02-01-10" => {
assert_eq!("file 1\nfile 1\n", file);
}
"2020-02-01-11" => {
assert_eq!("file 2\nfile 2\n", file);
}
x => panic!("unexpected date {}", x),
}
}
}
#[test]
fn test_max_log_files() {
use std::sync::{Arc, Mutex};
use tracing_subscriber::prelude::*;
let format = format_description::parse(
"[year]-[month]-[day] [hour]:[minute]:[second] [offset_hour \
sign:mandatory]:[offset_minute]:[offset_second]",
)
.unwrap();
let now = OffsetDateTime::parse("2020-02-01 10:01:00 +00:00:00", &format).unwrap();
let directory = tempfile::tempdir().expect("failed to create tempdir");
let (state, writer) = Inner::new(
now,
Rotation::HOURLY,
directory.path(),
Some("test_max_log_files".to_string()),
None,
Some(2),
)
.unwrap();
let clock = Arc::new(Mutex::new(now));
let now = {
let clock = clock.clone();
Box::new(move || *clock.lock().unwrap())
};
let appender = RollingFileAppender { state, writer, now };
let default = tracing_subscriber::fmt()
.without_time()
.with_level(false)
.with_target(false)
.with_max_level(tracing_subscriber::filter::LevelFilter::TRACE)
.with_writer(appender)
.finish()
.set_default();
tracing::info!("file 1");
// advance time by one second
(*clock.lock().unwrap()) += Duration::seconds(1);
tracing::info!("file 1");
// advance time by one hour
(*clock.lock().unwrap()) += Duration::hours(1);
// depending on the filesystem, the creation timestamp's resolution may
// be as coarse as one second, so we need to wait a bit here to ensure
// that the next file actually is newer than the old one.
std::thread::sleep(std::time::Duration::from_secs(1));
tracing::info!("file 2");
// advance time by one second
(*clock.lock().unwrap()) += Duration::seconds(1);
tracing::info!("file 2");
// advance time by one hour
(*clock.lock().unwrap()) += Duration::hours(1);
// again, sleep to ensure that the creation timestamps actually differ.
std::thread::sleep(std::time::Duration::from_secs(1));
tracing::info!("file 3");
// advance time by one second
(*clock.lock().unwrap()) += Duration::seconds(1);
tracing::info!("file 3");
drop(default);
let dir_contents = fs::read_dir(directory.path()).expect("Failed to read directory");
println!("dir={:?}", dir_contents);
for entry in dir_contents {
println!("entry={:?}", entry);
let path = entry.expect("Expected dir entry").path();
let file = fs::read_to_string(&path).expect("Failed to read file");
println!("path={}\nfile={:?}", path.display(), file);
match path
.extension()
.expect("found a file without a date!")
.to_str()
.expect("extension should be UTF8")
{
"2020-02-01-10" => {
panic!("this file should have been pruned already!");
}
"2020-02-01-11" => {
assert_eq!("file 2\nfile 2\n", file);
}
"2020-02-01-12" => {
assert_eq!("file 3\nfile 3\n", file);
}
x => panic!("unexpected date {}", x),
}
}
}
}