feat: system page caching via SystemCache + system_cache SQLite table

Add a TTL-based cache for the expensive checks on the admin system page, eliminating repeated systemctl subprocess calls (~4×~100ms), curl self-pings (~200-500ms), disk_*_space() and PHP ini reads on every page load. Changes: - storage/migrations/007_system_cache.sql: new migration creating the system_cache table (key TEXT PK, value TEXT, updated_at INTEGER) - storage/schema.sql: system_cache table added before pages table - Applied migration to live storage/posterg.db - src/SystemCache.php: new class with get/set/isStale/ageSeconds/invalidate; uses SQLite INSERT … ON CONFLICT upsert; no external dependencies - src/Database.php: added getDatabasePath(): string accessor - public/admin/system.php: - Bootstrap SystemCache at request start using the existing DB PDO handle - system_status: cached with 2-min TTL (systemctl + curl checks) - php_info: cached with 1-hour TTL (PHP ini values are runtime-constant) - disk_info: cached with 5-min TTL (total/free/used/pct tuple) - Logs section: unchanged — always reads live log tail per active tab - ?refresh=1 GET param invalidates all three cache keys before rendering - Status panel heading shows cache badge: '⚡ Cache — il y a Xs' (hit) or '⟳ Actualisé' (miss/fresh), styled via new .sys-cache-badge rules - public/assets/css/system.css: .sys-cache-badge / --hit / --miss styles
2026-05-06 11:09:18 +02:00 · 2026-04-02 13:04:00 +02:00
parent 592b1183db
commit ba7814c6dc
8 changed files with 317 additions and 105 deletions
--- a/TODO.md
+++ b/TODO.md
@@ -58,20 +58,22 @@ The admin system page (`/admin/system.php`) runs expensive operations on every l
 - Nginx config file reading

 ### Solution: `system_cache` table + background refresh
- [ ] **Add `system_cache` table** to schema: `CREATE TABLE system_cache (key TEXT PRIMARY KEY, value TEXT NOT NULL, updated_at INTEGER NOT NULL)` — stores JSON-encoded status snapshots keyed by section
- [ ] **Add migration** `storage/migrations/007_system_cache.sql` to create the table
- [ ] **Add `SystemCache` class** (`src/SystemCache.php`) with methods:
+- [x] **Add `system_cache` table** to schema: `CREATE TABLE system_cache (key TEXT PRIMARY KEY, value TEXT NOT NULL, updated_at INTEGER NOT NULL)` — stores JSON-encoded status snapshots keyed by section
+- [x] **Add migration** `storage/migrations/007_system_cache.sql` to create the table
+- [x] **Add `SystemCache` class** (`src/SystemCache.php`) with methods:
  - `get(string $key, int $maxAgeSec = 60): ?array` — returns cached JSON data if fresh, null if stale
  - `set(string $key, array $data): void` — upserts cache row
  - `isStale(string $key, int $maxAgeSec = 60): bool`
- [ ] **Refactor `system.php` status section** to:
+  - `ageSeconds(string $key): ?int` — returns age of cached entry in seconds
+  - `invalidate(string $key): void` — force-deletes a cache entry
+- [x] **Refactor `system.php` status section** to:
  1. Check `SystemCache::get('system_status', 120)` — 2-minute TTL
  2. If cache hit → render from cache, show "mis en cache il y a X sec" label
  3. If cache miss → run checks, store in cache, render
  4. Add `?refresh=1` GET param to force-bypass cache
- [ ] **Refactor `system.php` log sections** to not cache (logs should always be live) but avoid re-reading on every tab switch — only read the active tab's log
- [ ] **Cache disk info** separately with 5-minute TTL: `SystemCache::get('disk_info', 300)`
- [ ] **Cache PHP info** separately with 1-hour TTL: `SystemCache::get('php_info', 3600)` — PHP config doesn't change at runtime
+- [x] **Refactor `system.php` log sections** to not cache (logs should always be live) but avoid re-reading on every tab switch — only read the active tab's log
+- [x] **Cache disk info** separately with 5-minute TTL: `SystemCache::get('disk_info', 300)`
+- [x] **Cache PHP info** separately with 1-hour TTL: `SystemCache::get('php_info', 3600)` — PHP config doesn't change at runtime

 ## In Progress (from previous plan)
 - [ ] Extract `SearchController` — most complex public page (§2 step 4)
--- a/public/admin/system.php
+++ b/public/admin/system.php
@@ -1,10 +1,24 @@
 <?php
 require_once __DIR__ . "/../../config/bootstrap.php";
 require_once __DIR__ . '/../../src/AdminAuth.php';
+require_once APP_ROOT . '/src/Database.php';
+require_once APP_ROOT . '/src/SystemCache.php';
 AdminAuth::requireLogin();

 $pageTitle = "Système";

+// Bootstrap cache (uses the same SQLite DB as the app)
+$_db    = new Database();
+$_cache = new SystemCache($_db->getPDO());
+
+// ?refresh=1 force-busts all cached sections
+$forceRefresh = isset($_GET['refresh']) && $_GET['refresh'] === '1';
+if ($forceRefresh) {
+    $_cache->invalidate('system_status');
+    $_cache->invalidate('disk_info');
+    $_cache->invalidate('php_info');
+}
+
 // ═══════════════════════════════════════════════════════════════════════════════
 // SECTION 1 — STATUS DATA
 // ═══════════════════════════════════════════════════════════════════════════════
@@ -71,6 +85,15 @@ function statusClass(string $status): string {
    };
 }

+// ── system_status cache (2-minute TTL: systemctl + curl checks) ─────────────
+$statusCacheAge = $_cache->ageSeconds('system_status');
+$checksFromCache = $_cache->get('system_status', 120);
+
+if ($checksFromCache !== null) {
+    $checks = $checksFromCache;
+    $statusCached = true;
+} else {
+    $statusCached = false;
    $checks = [];

    // nginx
@@ -108,9 +131,8 @@ $checks['site_http'] = [
        'detail' => $httpResult !== null ? "HTTP {$httpResult[0]} — {$httpResult[1]} ms" : 'curl indisponible',
    ];

-// Database
-require_once APP_ROOT . '/src/Database.php';
-$dbPath     = APP_ROOT . '/storage/test.db';
+    // Database (DB object already created above, reuse it)
+    $dbPath      = $_db->getDatabasePath();
    $dbExists    = file_exists($dbPath);
    $dbWritable  = $dbExists && is_writable($dbPath);
    $dbSizeBytes = $dbExists ? filesize($dbPath) : null;
@@ -119,12 +141,10 @@ $dbSizeHuman = $dbSizeBytes !== null
            ? number_format($dbSizeBytes / 1048576, 1) . ' MB'
            : number_format($dbSizeBytes / 1024, 1) . ' KB')
        : 'N/A';
-
    $dbRowCount = null;
    if ($dbExists) {
        try {
-        $db = new Database();
-        $dbRowCount = $db->getThesisCount();
+            $dbRowCount = $_db->getThesisCount();
        } catch (Throwable $e) {
            $dbRowCount = null;
        }
@@ -161,7 +181,15 @@ $checks['maintenance'] = [
        'detail' => $maintenanceOn ? 'Activé — site public inaccessible' : 'Désactivé',
    ];

-// PHP info
+    $_cache->set('system_status', $checks);
+    $statusCacheAge = 0;
+}
+
+// ── php_info cache (1-hour TTL: PHP ini values don't change at runtime) ───────
+$phpInfoFromCache = $_cache->get('php_info', 3600);
+if ($phpInfoFromCache !== null) {
+    $phpInfo = $phpInfoFromCache;
+} else {
    $phpInfo = [
        'version'      => PHP_VERSION,
        'sapi'         => PHP_SAPI,
@@ -170,12 +198,28 @@ $phpInfo = [
        'post_max'     => ini_get('post_max_size'),
        'max_exec'     => ini_get('max_execution_time') . 's',
    ];
+    $_cache->set('php_info', $phpInfo);
+}

-// Disk
+// ── disk_info cache (5-minute TTL) ────────────────────────────────────────────
+$diskFromCache = $_cache->get('disk_info', 300);
+if ($diskFromCache !== null) {
+    $diskTotal = $diskFromCache['total'];
+    $diskFree  = $diskFromCache['free'];
+    $diskUsed  = $diskFromCache['used'];
+    $diskPct   = $diskFromCache['pct'];
+} else {
    $diskTotal = disk_total_space(APP_ROOT);
    $diskFree  = disk_free_space(APP_ROOT);
    $diskUsed  = $diskTotal - $diskFree;
    $diskPct   = $diskTotal > 0 ? (int) round($diskUsed / $diskTotal * 100) : 0;
+    $_cache->set('disk_info', [
+        'total' => $diskTotal,
+        'free'  => $diskFree,
+        'used'  => $diskUsed,
+        'pct'   => $diskPct,
+    ]);
+}

 // ═══════════════════════════════════════════════════════════════════════════════
 // SECTION 2 — LOGS DATA
@@ -377,7 +421,8 @@ require_once APP_ROOT . '/templates/head.php';

    <p class="sys-refresh-note">
        Affiché le <?= date('d/m/Y à H:i:s') ?> —
-        <a href="?tab=<?= htmlspecialchars($activeTab) ?>&amp;n=<?= $selectedN ?>">Rafraîchir</a>
+        <a href="?tab=<?= htmlspecialchars($activeTab) ?>&amp;n=<?= $selectedN ?>">Rafraîchir</a> —
+        <a href="?tab=<?= htmlspecialchars($activeTab) ?>&amp;n=<?= $selectedN ?>&amp;refresh=1">Forcer actualisation</a>
    </p>

    <!-- ── Tab bar ─────────────────────────────────────────────────────── -->
@@ -399,7 +444,17 @@ require_once APP_ROOT . '/templates/head.php';
         STATUS PANEL
    ════════════════════════════════════════════════════════════════════ -->

-    <h2 class="srv-section-title">Services</h2>
+    <h2 class="srv-section-title">Services
+        <?php if ($statusCached && $statusCacheAge !== null): ?>
+        <span class="sys-cache-badge sys-cache-badge--hit" title="Données en cache">
+            ⚡ Cache — il y a <?= $statusCacheAge ?>s
+        </span>
+        <?php else: ?>
+        <span class="sys-cache-badge sys-cache-badge--miss" title="Données fraîches">
+            ⟳ Actualisé
+        </span>
+        <?php endif; ?>
+    </h2>
    <div class="srv-grid">
        <?php foreach ($checks as $check): ?>
        <?php $st = $check['status'] ?? 'unknown'; ?>
--- a/public/assets/css/system.css
+++ b/public/assets/css/system.css
@@ -254,6 +254,29 @@
 }
 .sys-refresh-note a:hover { text-decoration: underline; }

+/* ── Cache freshness badges ──────────────────────────────────────────────── */
+.sys-cache-badge {
+    display: inline-block;
+    font-size: .68rem;
+    font-weight: 400;
+    font-family: ui-monospace, monospace;
+    padding: .1rem .45rem;
+    border-radius: 3px;
+    margin-left: .7rem;
+    vertical-align: middle;
+    line-height: 1.6;
+}
+.sys-cache-badge--hit {
+    background: rgba(255,193,7,.12);
+    color: #ffc107;
+    border: 1px solid rgba(255,193,7,.35);
+}
+.sys-cache-badge--miss {
+    background: rgba(76,175,80,.12);
+    color: #4caf50;
+    border: 1px solid rgba(76,175,80,.35);
+}
+
 /* ── Nginx config viewer ───────────────────────────────────────────────── */
 .nginx-source-badge {
    display: inline-block;
--- a/src/Database.php
+++ b/src/Database.php
@@ -77,6 +77,13 @@ class Database {
        return $this->pdo;
    }

+    /**
+     * Return the resolved path of the database file in use.
+     */
+    public function getDatabasePath(): string {
+        return $this->dbPath;
+    }
+
    // ========================================================================
    // TRANSACTION SUPPORT (from formulaire)
    // ========================================================================
--- a/src/SystemCache.php
+++ b/src/SystemCache.php
@@ -0,0 +1,111 @@
+<?php
+
+/**
+ * SystemCache — thin TTL cache for admin system page checks.
+ *
+ * Stores JSON-encoded data blobs in the `system_cache` SQLite table.
+ * The table has a single schema:
+ *   key TEXT PRIMARY KEY, value TEXT NOT NULL, updated_at INTEGER NOT NULL
+ *
+ * Usage:
+ *   $cache = new SystemCache($pdo);
+ *
+ *   // Read (returns array or null if stale/missing)
+ *   $data = $cache->get('system_status', 120);
+ *
+ *   // Write
+ *   $cache->set('system_status', $myArray);
+ *
+ *   // Check freshness without reading value
+ *   if ($cache->isStale('disk_info', 300)) { ... }
+ *
+ *   // Force-invalidate a key (e.g. on ?refresh=1)
+ *   $cache->invalidate('system_status');
+ */
+class SystemCache
+{
+    private PDO $pdo;
+
+    public function __construct(PDO $pdo)
+    {
+        $this->pdo = $pdo;
+    }
+
+    /**
+     * Return cached data for $key if it is no older than $maxAgeSec seconds.
+     * Returns null when the entry is missing or stale.
+     */
+    public function get(string $key, int $maxAgeSec = 60): ?array
+    {
+        $stmt = $this->pdo->prepare(
+            'SELECT value, updated_at FROM system_cache WHERE key = ?'
+        );
+        $stmt->execute([$key]);
+        $row = $stmt->fetch(PDO::FETCH_ASSOC);
+
+        if (!$row) {
+            return null;
+        }
+
+        if ((time() - (int)$row['updated_at']) > $maxAgeSec) {
+            return null; // stale
+        }
+
+        $decoded = json_decode((string)$row['value'], true);
+        return is_array($decoded) ? $decoded : null;
+    }
+
+    /**
+     * Upsert $data (JSON-encoded) for $key with current timestamp.
+     */
+    public function set(string $key, array $data): void
+    {
+        $stmt = $this->pdo->prepare(
+            'INSERT INTO system_cache (key, value, updated_at)
+             VALUES (?, ?, ?)
+             ON CONFLICT(key) DO UPDATE SET value = excluded.value, updated_at = excluded.updated_at'
+        );
+        $stmt->execute([$key, json_encode($data), time()]);
+    }
+
+    /**
+     * Return true when the entry is missing or older than $maxAgeSec.
+     */
+    public function isStale(string $key, int $maxAgeSec = 60): bool
+    {
+        $stmt = $this->pdo->prepare(
+            'SELECT updated_at FROM system_cache WHERE key = ?'
+        );
+        $stmt->execute([$key]);
+        $row = $stmt->fetch(PDO::FETCH_ASSOC);
+
+        if (!$row) {
+            return true;
+        }
+
+        return (time() - (int)$row['updated_at']) > $maxAgeSec;
+    }
+
+    /**
+     * Return the age of the cached entry in seconds, or null if missing.
+     */
+    public function ageSeconds(string $key): ?int
+    {
+        $stmt = $this->pdo->prepare(
+            'SELECT updated_at FROM system_cache WHERE key = ?'
+        );
+        $stmt->execute([$key]);
+        $row = $stmt->fetch(PDO::FETCH_ASSOC);
+
+        return $row ? (time() - (int)$row['updated_at']) : null;
+    }
+
+    /**
+     * Delete a cached entry, forcing the next get() to re-compute.
+     */
+    public function invalidate(string $key): void
+    {
+        $stmt = $this->pdo->prepare('DELETE FROM system_cache WHERE key = ?');
+        $stmt->execute([$key]);
+    }
+}
--- a/storage/migrations/007_system_cache.sql
+++ b/storage/migrations/007_system_cache.sql
@@ -0,0 +1,8 @@
+-- Migration 007: Add system_cache table for admin system page caching
+-- Stores JSON-encoded status snapshots keyed by section with a TTL mechanism.
+
+CREATE TABLE IF NOT EXISTS system_cache (
+    key        TEXT    PRIMARY KEY,
+    value      TEXT    NOT NULL,
+    updated_at INTEGER NOT NULL
+);
--- a/storage/posterg.db
+++ b/storage/posterg.db
--- a/storage/schema.sql
+++ b/storage/schema.sql
@@ -283,6 +283,12 @@ CREATE TABLE IF NOT EXISTS thesis_files (
 -- ============================================================================

 -- For managing editable static pages (charte, about, licenses, contact)
+CREATE TABLE IF NOT EXISTS system_cache (
+    key        TEXT    PRIMARY KEY,
+    value      TEXT    NOT NULL,
+    updated_at INTEGER NOT NULL
+);
+
 CREATE TABLE IF NOT EXISTS pages (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    slug TEXT NOT NULL UNIQUE, -- 'charte', 'about', 'licenses', 'contact'