nur-ture/src/file/cache/CacheFile.php

349 lines
10 KiB
PHP

<?php
namespace nulib\file\cache;
use Exception;
use nulib\cl;
use nulib\cv;
use nulib\file;
use nulib\file\SharedFile;
use nulib\os\path;
use nulib\php\time\DateTime;
use nulib\php\time\Delay;
use nulib\str;
use nulib\ValueException;
class CacheFile extends SharedFile {
/** @var string|int durée de vie par défaut des données mises en cache */
const DURATION = "1D"; // jusqu'au lendemain
const EXT = ".cache";
function __construct($file, ?array $params=null) {
if ($file === null) {
$rand = bin2hex(random_bytes(8));
$file = sys_get_temp_dir()."/$rand";
}
$file = path::ensure_ext($file, self::EXT);
$this->basedir = path::dirname($file);
$basename = path::filename($file);
$this->basename = str::without_suffix(self::EXT, $basename);
$this->initialDuration = Delay::with($params["duration"] ?? static::DURATION);
$this->overrideDuration = $params["override_duration"] ?? false;
$this->readonly = $params["readonly"] ?? false;
$this->cacheNull = $params["cache_null"] ?? false;
$data = $params["data"] ?? null;
if ($data === null) {
$this->dataDefs = null;
$this->data = null;
} elseif ($data instanceof CacheData) {
$this->dataDefs = null;
$this->data = $data;
} elseif (!is_array($data)) {
$this->dataDefs = null;
$this->data = $this->getData($data);
} else {
$dataDefs = [];
$tmpdefs = $data;
$index = 0;
foreach ($tmpdefs as $key => $data) {
$odef = $data;
if ($data instanceof CacheData) {
} elseif (cv::subclass_of($data, CacheData::class)) {
$data = new $data();
} else {
throw ValueException::invalid_type($odef, CacheData::class);
}
if ($key === $index) {
$index++;
$key = $data->getName();
}
$dataDefs[$key] = $data;
}
$this->dataDefs = $dataDefs;
}
parent::__construct($file);
}
/** @var string répertoire de base des fichiers de cache */
protected string $basedir;
/** @var string nom de base des fichiers de cache */
protected string $basename;
protected Delay $initialDuration;
protected bool $overrideDuration;
protected bool $readonly;
protected bool $cacheNull;
protected ?array $dataDefs;
protected ?CacheData $data;
protected function getData($data): CacheData {
if ($data === null) {
return $this->data ??= new CacheData(function() {
return $this->compute();
});
}
$odata = $data;
if (is_string($data) || is_int($data)) {
$data = $this->dataDefs[$data] ?? null;
if ($data === null) throw ValueException::invalid_key($odata);
}
if ($data instanceof CacheData) return $data;
throw ValueException::invalid_type($odata, CacheData::class);
}
/**
* vérifier si le fichier est valide. s'il est invalide, il faut le recréer.
*
* on assume que le fichier existe, vu qu'il a été ouvert en c+b
*/
protected function isValid(): bool {
# considèrer que le fichier est invalide s'il est de taille nulle
return $this->getSize() > 0;
}
protected ?DateTime $start;
protected ?Delay $duration;
protected ?array $datafilenames;
/** charger les données. le fichier a déjà été verrouillé en lecture */
protected function loadMetadata(): void {
if ($this->isValid()) {
$this->rewind();
[
"start" => $start,
"duration" => $duration,
"datafiles" => $datafilenames,
] = $this->unserialize(null, false, true);
if ($this->overrideDuration) {
$duration = Delay::with($this->initialDuration, $start);
}
$datafilenames = array_fill_keys($datafilenames, true);
} else {
$start = null;
$duration = null;
$datafilenames = [];
}
$this->start = $start;
$this->duration = $duration;
$this->datafilenames = $datafilenames;
}
/**
* tester s'il faut mettre les données à jour. le fichier a déjà été
* verrouillé en lecture
*/
protected function shouldUpdate(bool $noCache=false): bool {
if ($this->isValid()) {
$expired = $this->duration->isElapsed();
} else {
$expired = false;
$noCache = true;
}
return $noCache || $expired;
}
/** sauvegarder les données. le fichier a déjà été verrouillé en écriture */
protected function saveMetadata(): void {
$this->duration ??= $this->initialDuration;
if ($this->start === null) {
$this->start = new DateTime();
$this->duration = Delay::with($this->duration, $this->start);
}
$datafilenames = array_keys($this->datafilenames);
$this->ftruncate();
$this->serialize([
"start" => $this->start,
"duration" => $this->duration,
"datafiles" => $datafilenames,
], false, true);
}
protected function loadData(string $datafile) {
return file::reader($datafile)->unserialize();
}
protected function saveData(string $datafile, $data): void {
file::writer($datafile)->serialize($data);
}
protected function unlinkDatafile(string $datafilename): void {
$datafile = path::join($this->basedir, $datafilename);
@unlink($datafile);
unset($this->datafilenames[$datafilename]);
}
protected function unlinkFiles(bool $datafilesOnly=false): void {
if (!$datafilesOnly) @unlink($this->file);
foreach ($this->datafilenames as $datafilename) {
$this->unlinkDatafile($datafilename);
}
}
/** tester si $value peut être mis en cache */
protected function shouldCache($value): bool {
return $this->cacheNull || $value !== null;
}
protected ?DateTime $ostart;
protected ?Delay $oduration;
protected ?array $odatafilenames;
protected function beforeAction() {
$this->loadMetadata();
$this->ostart = cv::clone($this->start);
$this->oduration = cv::clone($this->duration);
$this->odatafilenames = cv::clone($this->datafilenames);
}
protected function afterAction() {
$start = $this->start;
$duration = $this->duration;
$oduration = $this->oduration;
$datafilenames = $this->datafilenames;
$modified = false;
if ($start != $this->ostart) $modified = true;
if ($duration === null || $oduration === null) $modified = true;
elseif ($duration->getDest() != $oduration->getDest()) $modified = true;
# égalité stricte uniquement pour $datafiles qui est un array
if ($datafilenames !== $this->odatafilenames) $modified = true;
if ($modified && !$this->readonly) {
$this->lockWrite();
$this->saveMetadata();
}
}
protected function action(callable $callback, bool $willWrite=false) {
if ($willWrite && !$this->readonly) $this->lockWrite();
else $this->lockRead();
try {
$this->beforeAction();
$result = $callback();
$this->afterAction();
return $result;
} finally {
$this->start = null;
$this->duration = null;
$this->datafilenames = null;
$this->unlock(true);
}
}
protected function compute() {
return null;
}
function get($data=null, bool $noCache=false) {
return $this->action(function () use ($data, $noCache) {
$data = $this->getData($data);
$dataname = $data->getName();
$datafilename = ".{$this->basename}.{$dataname}".self::EXT;
$datafile = path::join($this->basedir, $datafilename);
$updateMetadata = $this->shouldUpdate($noCache);
$updateData = !array_key_exists($datafilename, $this->datafilenames);
if (!$this->readonly && ($updateMetadata || $updateData)) {
$this->lockWrite();
if ($updateMetadata) {
# il faut refaire tout le cache
$this->unlinkFiles(true);
$updateData = true;
}
if ($updateData) {
# calculer un fichier
try {
$data = $data->get();
} catch (Exception $e) {
# ne pas garder le fichier en cas d'exception
$this->unlinkDatafile($datafile);
throw $e;
}
} elseif (file_exists($datafile)) {
$data = $this->loadData($datafile);
} else {
$data = null;
}
if ($this->shouldCache($data)) {
$this->saveData($datafile, $data);
$this->datafilenames[$datafilename] = true;
} else {
# ne pas garder le fichier s'il ne faut pas mettre en cache
$this->unlinkDatafile($datafile);
}
} elseif (file_exists($datafile)) {
$data = $this->loadData($datafile);
} else {
$data = null;
}
return $data;
});
}
/** obtenir les informations sur le fichier */
function getInfos(): array {
return $this->action(function () {
if (!$this->isValid()) {
return ["valid" => false];
}
$start = $this->start;
$duration = $this->duration;
$datafilenames = $this->datafilenames;
$datafiles = [];
foreach (array_keys($datafilenames) as $datafilename) {
$datafile = path::join($this->basedir, $datafilename);
$name = $datafilename;
str::del_prefix($name, ".{$this->basename}.");
str::del_suffix($name, self::EXT);
if (file_exists($datafile)) {
$size = filesize($datafile);
} else {
$size = null;
}
$datafiles[$name] = $size;
}
return [
"valid" => true,
"start" => $start,
"duration" => strval($duration),
"date_start" => $start->format(),
"date_end" => $duration->getDest()->format(),
"datafiles" => $datafiles,
];
});
}
const UPDATE_SUB = -1, UPDATE_SET = 0, UPDATE_ADD = 1;
/** mettre à jour la durée de validité du fichier */
function updateDuration($nduration, int $action=1): void {
if ($this->readonly) return;
$this->action(function () use ($nduration, $action) {
if (!$this->isValid()) return;
$duration = $this->duration;
if ($action < 0) $duration->subDuration($nduration);
elseif ($action > 0) $duration->addDuration($nduration);
}, true);
}
/** supprimer les fichiers s'ils ont expiré */
function deleteExpired(bool $force=false): bool {
if ($this->readonly) return false;
return $this->action(function () use ($force) {
if ($force || $this->shouldUpdate()) {
$this->unlinkFiles();
return true;
}
return false;
}, true);
}
}