From 4c91327bacf8c3b307de535a92ac509fd7625781 Mon Sep 17 00:00:00 2001
From: Jephte Clain <Jephte.Clain@univ-reunion.fr>
Date: Fri, 23 May 2025 05:02:31 +0400
Subject: [PATCH] =?UTF-8?q?db/cache=20doit=20encore=20=C3=AAtre=20travaill?=
 =?UTF-8?q?=C3=A9?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/db/cache/CacheChannel.php | 116 ++++++++++++++++++++++++++++++++++
 src/db/cache/RowsChannel.php  |  51 +++++++++++++++
 src/db/cache/cache.php        |  37 +++++++++++
 3 files changed, 204 insertions(+)
 create mode 100644 src/db/cache/CacheChannel.php
 create mode 100644 src/db/cache/RowsChannel.php
 create mode 100644 src/db/cache/cache.php

diff --git a/src/db/cache/CacheChannel.php b/src/db/cache/CacheChannel.php
new file mode 100644
index 0000000..b1f8619
--- /dev/null
+++ b/src/db/cache/CacheChannel.php
@@ -0,0 +1,116 @@
+<?php
+namespace nulib\db\cache;
+
+use nulib\cl;
+use nulib\db\CapacitorChannel;
+use nulib\php\time\DateTime;
+use nulib\php\time\Delay;
+
+class CacheChannel extends CapacitorChannel {
+  /** @var int durée de vie par défaut du cache */
+  const DURATION = "1D"; // jusqu'au lendemain
+
+  const INCLUDES = null;
+
+  const EXCLUDES = null;
+
+  const COLUMN_DEFINITIONS = [
+    "group_id" => "varchar(64) not null",
+    "id" => "varchar(64) not null",
+    "date_start" => "datetime",
+    "duration_" => "text",
+    "primary key (group_id, id)",
+  ];
+
+  static function get_cache_ids($id): array {
+    if (is_array($id)) {
+      $keys = array_keys($id);
+      if (array_key_exists("group_id", $id)) $groupIdKey = "group_id";
+      else $groupIdKey = $keys[1] ?? null;
+      $groupId = $id[$groupIdKey] ?? "";
+      if (array_key_exists("id", $id)) $idKey = "id";
+      else $idKey = $keys[0] ?? null;
+      $id = $id[$idKey] ?? "";
+    } else {
+      $groupId = "";
+    }
+    if (preg_match('/^(.*\\\\)?([^\\\\]+)$/', $groupId, $ms)) {
+      # si le groupe est une classe, faire un hash du package pour limiter la
+      # longueur du groupe
+      [$package, $groupId] = [$ms[1], $ms[2]];
+      $package = substr(md5($package), 0, 4);
+      $groupId = "${groupId}_$package";
+    }
+    return ["group_id" => $groupId, "id" => $id];
+  }
+
+  function __construct(?string $duration=null, ?string $name=null) {
+    parent::__construct($name);
+    $this->duration = $duration ?? static::DURATION;
+    $this->includes = static::INCLUDES;
+    $this->excludes = static::EXCLUDES;
+  }
+
+  protected string $duration;
+
+  protected ?array $includes;
+
+  protected ?array $excludes;
+
+  function getItemValues($item): ?array {
+    return cl::merge(self::get_cache_ids($item), [
+      "item" => null,
+    ]);
+  }
+
+  function onCreate($item, array $values, ?array $alwaysNull, ?string $duration=null): ?array {
+    $now = new DateTime();
+    $duration ??= $this->duration;
+    return [
+      "date_start" => $now,
+      "duration" => new Delay($duration, $now),
+    ];
+  }
+
+  function onUpdate($item, array $values, array $pvalues, ?string $duration=null): ?array {
+    $now = new DateTime();
+    $duration ??= $this->duration;
+    return [
+      "date_start" => $now,
+      "duration" => new Delay($duration, $now),
+    ];
+  }
+
+  function shouldUpdate($id, bool $noCache=false): bool {
+    if ($noCache) return true;
+
+    $cacheIds = self::get_cache_ids($id);
+    $groupId = $cacheIds["group_id"];
+    if ($groupId) {
+      $includes = $this->includes;
+      $shouldInclude = $includes !== null && in_array($groupId, $includes);
+      $excludes = $this->excludes;
+      $shouldExclude = $excludes !== null && in_array($groupId, $excludes);
+      if (!$shouldInclude || $shouldExclude) return true;
+    }
+
+    $found = false;
+    $expired = false;
+    $this->each($cacheIds,
+      function($item, $values) use (&$found, &$expired) {
+        $found = true;
+        $expired = $values["duration"]->isElapsed();
+      });
+    return !$found || $expired;
+  }
+
+  function setCached($id, ?string $duration=null): void {
+    $cacheIds = self::get_cache_ids($id);
+    $this->charge($cacheIds, null, [$duration]);
+  }
+
+  function resetCached($id) {
+    $cacheIds = self::get_cache_ids($id);
+    $this->delete($cacheIds);
+  }
+}
diff --git a/src/db/cache/RowsChannel.php b/src/db/cache/RowsChannel.php
new file mode 100644
index 0000000..a3f7055
--- /dev/null
+++ b/src/db/cache/RowsChannel.php
@@ -0,0 +1,51 @@
+<?php
+namespace nulib\db\cache;
+
+use Closure;
+use IteratorAggregate;
+use nulib\cl;
+use nulib\db\CapacitorChannel;
+use Traversable;
+
+class RowsChannel extends CapacitorChannel implements IteratorAggregate {
+  const COLUMN_DEFINITIONS = [
+    "key" => "varchar(128) primary key not null",
+    "all_values" => "mediumtext",
+  ];
+
+  function __construct($id, callable $builder, ?string $duration=null) {
+    $this->cacheIds = $cacheIds = CacheChannel::get_cache_ids($id);
+    $this->builder = Closure::fromCallable($builder);
+    $this->duration = $duration;
+    $name = "{$cacheIds["group_id"]}-{$cacheIds["id"]}";
+    parent::__construct($name);
+  }
+
+  protected array $cacheIds;
+
+  protected Closure $builder;
+
+  protected ?string $duration = null;
+
+  function getItemValues($item): ?array {
+    $key = array_keys($item)[0];
+    $row = $item[$key];
+    return [
+      "key" => $key,
+      "item" => $row,
+      "all_values" => implode(" ", cl::filter_n(cl::with($row))),
+    ];
+  }
+
+  function getIterator(): Traversable {
+    $cm = cache::get();
+    if ($cm->shouldUpdate($this->cacheIds)) {
+      $this->capacitor->reset();
+      foreach (($this->builder)() as $key => $row) {
+        $this->charge([$key => $row]);
+      }
+      $cm->setCached($this->cacheIds, $this->duration);
+    }
+    return $this->discharge(false);
+  }
+}
diff --git a/src/db/cache/cache.php b/src/db/cache/cache.php
new file mode 100644
index 0000000..401fb19
--- /dev/null
+++ b/src/db/cache/cache.php
@@ -0,0 +1,37 @@
+<?php
+namespace nulib\db\cache;
+
+use nulib\db\Capacitor;
+use nulib\db\CapacitorStorage;
+use nulib\db\sqlite\SqliteStorage;
+
+class cache {
+  protected static ?CapacitorStorage $storage = null;
+
+  static function set_storage(CapacitorStorage $storage): CapacitorStorage {
+    return self::$storage = $storage;
+  }
+
+  protected static function get_storage(): CapacitorStorage {
+    return self::$storage ??= new SqliteStorage("");
+  }
+
+  protected static ?CacheChannel $channel = null;
+
+  static function set(?CacheChannel $channel): CacheChannel {
+    $channel ??= new CacheChannel();
+    new Capacitor(self::get_storage(), $channel);
+    return self::$channel = $channel;
+  }
+
+  static function get(): CacheChannel {
+    if (self::$channel !== null) return self::$channel;
+    else return self::set(null);
+  }
+
+  static function new(?RowsChannel $channel, $id=null, ?callable $builder=null): RowsChannel {
+    $channel ??= new RowsChannel($id, $builder);
+    new Capacitor(self::get_storage(), $channel);
+    return $channel;
+  }
+}