use std::cmp::min;
use std::fs::File;
use std::io::{Read, Write};
use std::path::{Path, PathBuf};
use std::time::Duration;
use eyre::Result;
use flate2::Compression;
use flate2::read::ZlibDecoder;
use flate2::write::ZlibEncoder;
use itertools::Itertools;
use once_cell::sync::OnceCell;
use serde::Serialize;
use serde::de::DeserializeOwned;
use std::sync::LazyLock as Lazy;
use crate::build_time::built_info;
use crate::config::Settings;
use crate::file::{display_path, modified_duration};
use crate::hash::hash_to_str;
use crate::rand::random_string;
use crate::{dirs, file};
#[derive(Debug)]
pub struct CacheManagerBuilder {
cache_file_path: PathBuf,
cache_keys: Vec<String>,
fresh_duration: Option<Duration>,
fresh_files: Vec<PathBuf>,
}
pub static BASE_CACHE_KEYS: Lazy<Vec<String>> = Lazy::new(|| {
[
built_info::FEATURES_STR,
built_info::PKG_VERSION,
built_info::PROFILE,
built_info::TARGET,
]
.into_iter()
.map(|s| s.to_string())
.collect()
});
impl CacheManagerBuilder {
pub fn new(cache_file_path: impl AsRef<Path>) -> Self {
Self {
cache_file_path: cache_file_path.as_ref().to_path_buf(),
cache_keys: BASE_CACHE_KEYS.clone(),
fresh_files: vec![],
fresh_duration: None,
}
}
pub fn with_fresh_duration(mut self, duration: Option<Duration>) -> Self {
self.fresh_duration = duration;
self
}
pub fn with_fresh_file(mut self, path: PathBuf) -> Self {
self.fresh_files.push(path);
self
}
pub fn with_cache_key(mut self, key: String) -> Self {
self.cache_keys.push(key);
self
}
fn cache_key(&self) -> String {
hash_to_str(&self.cache_keys).chars().take(5).collect()
}
pub fn build<T>(self) -> CacheManager<T>
where
T: Serialize + DeserializeOwned,
{
let key = self.cache_key();
let (base, ext) = file::split_file_name(&self.cache_file_path);
let mut cache_file_path = self.cache_file_path;
cache_file_path.set_file_name(format!("{base}-{key}.{ext}"));
CacheManager {
cache_file_path,
cache: Box::new(OnceCell::new()),
fresh_files: self.fresh_files,
fresh_duration: self.fresh_duration,
}
}
}
#[derive(Debug, Clone)]
pub struct CacheManager<T>
where
T: Serialize + DeserializeOwned,
{
cache_file_path: PathBuf,
fresh_duration: Option<Duration>,
fresh_files: Vec<PathBuf>,
cache: Box<OnceCell<T>>,
}
impl<T> CacheManager<T>
where
T: Serialize + DeserializeOwned,
{
pub fn get_or_try_init<F>(&self, fetch: F) -> Result<&T>
where
F: FnOnce() -> Result<T>,
{
let val = self.cache.get_or_try_init(|| {
let path = &self.cache_file_path;
if self.is_fresh() {
match self.parse() {
Ok(val) => return Ok::<_, color_eyre::Report>(val),
Err(err) => {
warn!("failed to parse cache file: {} {:#}", path.display(), err);
}
}
}
let val = (fetch)()?;
if let Err(err) = self.write(&val) {
warn!("failed to write cache file: {} {:#}", path.display(), err);
}
Ok(val)
})?;
Ok(val)
}
fn parse(&self) -> Result<T> {
let path = &self.cache_file_path;
trace!("reading {}", display_path(path));
let mut zlib = ZlibDecoder::new(File::open(path)?);
let mut bytes = Vec::new();
zlib.read_to_end(&mut bytes)?;
Ok(rmp_serde::from_slice(&bytes)?)
}
pub fn write(&self, val: &T) -> Result<()> {
trace!("writing {}", display_path(&self.cache_file_path));
if let Some(parent) = self.cache_file_path.parent() {
file::create_dir_all(parent)?;
}
let partial_path = self
.cache_file_path
.with_extension(format!("part-{}", random_string(8)));
let mut zlib = ZlibEncoder::new(File::create(&partial_path)?, Compression::fast());
zlib.write_all(&rmp_serde::to_vec_named(&val)?[..])?;
file::rename(&partial_path, &self.cache_file_path)?;
Ok(())
}
#[cfg(test)]
pub fn clear(&self) -> Result<()> {
let path = &self.cache_file_path;
trace!("clearing cache {}", path.display());
if path.exists() {
file::remove_file(path)?;
}
Ok(())
}
fn is_fresh(&self) -> bool {
if !self.cache_file_path.exists() {
return false;
}
if let Some(fresh_duration) = self.freshest_duration() {
if let Ok(metadata) = self.cache_file_path.metadata() {
if let Ok(modified) = metadata.modified() {
return modified.elapsed().unwrap_or_default() < fresh_duration;
}
}
}
true
}
fn freshest_duration(&self) -> Option<Duration> {
let mut freshest = self.fresh_duration;
for path in self.fresh_files.iter().unique() {
let duration = modified_duration(path).unwrap_or_default();
freshest = Some(match freshest {
None => duration,
Some(freshest) => min(freshest, duration),
})
}
freshest
}
}
pub(crate) struct PruneResults {
pub(crate) size: u64,
pub(crate) count: u64,
}
pub(crate) struct PruneOptions {
pub(crate) dry_run: bool,
pub(crate) verbose: bool,
pub(crate) age: Duration,
}
pub(crate) fn auto_prune() -> Result<()> {
if rand::random::<u8>() % 10 != 0 {
return Ok(()); }
let settings = Settings::get();
let age = match settings.cache_prune_age_duration() {
Some(age) => age,
None => {
return Ok(());
}
};
let auto_prune_file = dirs::CACHE.join(".auto_prune");
if let Ok(Ok(modified)) = auto_prune_file.metadata().map(|m| m.modified()) {
if modified.elapsed().unwrap_or_default() < age {
return Ok(());
}
}
let empty = file::ls(*dirs::CACHE).unwrap_or_default().is_empty();
xx::file::touch_dir(&auto_prune_file)?;
if empty {
return Ok(());
}
debug!(
"pruning old cache files, this behavior can be modified with the MISE_CACHE_PRUNE_AGE setting"
);
prune(
*dirs::CACHE,
&PruneOptions {
dry_run: false,
verbose: false,
age,
},
)?;
Ok(())
}
pub(crate) fn prune(dir: &Path, opts: &PruneOptions) -> Result<PruneResults> {
let mut results = PruneResults { size: 0, count: 0 };
let remove = |file: &Path| {
if opts.dry_run || opts.verbose {
info!("pruning {}", display_path(file));
} else {
debug!("pruning {}", display_path(file));
}
if !opts.dry_run {
file::remove_file_or_dir(file)?;
}
Ok::<(), color_eyre::Report>(())
};
for subdir in file::dir_subdirs(dir)? {
let subdir = dir.join(&subdir);
let r = prune(&subdir, opts)?;
results.size += r.size;
results.count += r.count;
let metadata = subdir.metadata()?;
if file::ls(&subdir)?.is_empty()
&& metadata.modified()?.elapsed().unwrap_or_default() > opts.age
{
remove(&subdir)?;
results.count += 1;
}
}
for f in file::ls(dir)? {
let path = dir.join(&f);
let metadata = path.metadata()?;
let elapsed = metadata.accessed()?.elapsed().unwrap_or_default();
if elapsed > opts.age {
remove(&path)?;
results.size += metadata.len();
results.count += 1;
}
}
Ok(results)
}
#[cfg(test)]
mod tests {
use super::*;
use pretty_assertions::assert_eq;
#[test]
fn test_cache() {
let cache = CacheManagerBuilder::new(dirs::CACHE.join("test-cache")).build();
cache.clear().unwrap();
let val = cache.get_or_try_init(|| Ok(1)).unwrap();
assert_eq!(val, &1);
let val = cache.get_or_try_init(|| Ok(2)).unwrap();
assert_eq!(val, &1);
}
}