add file export system for admins

- ExportController: getAllThesisFiles(), buildExportManifest(), createExportZip()
  builds a ZIP archive with manifest.json + files/ mirror of storage/theses/
- Database: getAllThesisFilesForExport() queries all thesis_files + identifier
- AdminLogger: logFilesExport() audit log entry
- admin/actions/export-files.php: thin dispatcher, streams zip with headers
- templates/admin/index.php: 'Exporter fichiers' button next to CSV export

LDAP_SPEC.md

@@ -0,0 +1,141 @@
+# LDAP Authentication Specification for XAMXAM Admin
+
+## Current state
+
+Two-layer authentication guards the `/admin/` area:
+
+| Layer | Mechanism | Where |
+|-------|-----------|-------|
+| 1 (nginx) | `auth_basic` against `/etc/nginx/.htpasswd-xamxam` | `nginx/xamxam.conf` |
+| 2 (PHP) | `AdminAuth` — bcrypt hash in `site_settings.admin_password_hash` | `app/src/AdminAuth.php`, `app/public/admin/login.php`, `app/public/admin/actions/account.php` |
+
+Layer 1 controls the browser's Basic Auth dialog. Layer 2 provides a PHP session gate and a
+fallback login form. When both layers share the same password, the user is authenticated
+transparently (nginx passes `PHP_AUTH_PW` to PHP, `AdminAuth` verifies it against the DB hash).
+
+## Goal
+
+Replace both layers with LDAP-based authentication while preserving the defence-in-depth
+structure and the transparent user experience (single sign-on via the browser's Basic Auth
+dialog, no PHP login form unless fallback).
+
+## Required information from IT
+
+| # | Item | Example / format |
+|---|------|------------------|
+| 1 | **LDAP server URL** | `ldaps://ldap.erg.be:636` or `ldap://ldap.erg.be:389` |
+| 2 | **Base DN** | `dc=erg,dc=be` |
+| 3 | **Bind DN** (service / search account) | `cn=svc-xamxam,ou=services,dc=erg,dc=be` |
+| 4 | **Bind password** | (secret — read-only account is sufficient) |
+| 5 | **User search filter** | `(&(uid=%s)(memberOf=cn=admin-xamxam,ou=groups,dc=erg,dc=be))` — `%s` is the username entered in the Basic Auth dialog |
+| 6 | **Group membership mechanism** | `memberOf` attribute (AD-style) **or** `member`/`uniqueMember` on the group entry (OpenLDAP-style) |
+| 7 | **Username attribute** | Typically `uid` (OpenLDAP) or `sAMAccountName` (AD). What attribute should the user type in the auth dialog? |
+| 8 | **TLS certificate** | If `ldaps://` is used and the certificate is self-signed, provide the CA certificate (PEM). Otherwise confirm it's a publicly-trusted cert. |
+| 9 | **Admin group DN/CN** | The exact DN or CN that grants admin access (e.g. `cn=xamxam-admins,ou=groups,dc=erg,dc=be`). If there's no group yet, what should it be named? |
+
+## Architecture
+
+```
+Browser                    Nginx                       LDAP daemon              LDAP server
+  │                          │                              │                       │
+  │─ GET /admin/ ──────────►│                              │                       │
+  │◄── 401 WWW-Authenticate │                              │                       │
+  │─ GET /admin/ + Basic ──►│                              │                       │
+  │                         │─ POST /auth-ldap ───────────►│                       │
+  │                         │   (proxy Authorization hdr)  │─ ldap_bind ──────────►│
+  │                         │                              │◄── success ───────────│
+  │                         │                              │─ ldap_search ────────►│
+  │                         │                              │◄── group check OK ────│
+  │                         │◄── 200 OK ──────────────────│                       │
+  │                         │─ forward to PHP ────────────►                        │
+  │                         │                              │                       │
+  │◄── admin page ─────────│                                                       │
+```
+
+### Option A — `nginx-ldap-auth` daemon (preferred)
+
+- Drop-in replacement for `auth_basic` / `.htpasswd` using nginx's `auth_request` module
+- A small Python 3 daemon (`nginx-ldap-auth`) runs at `127.0.0.1:8888`
+- Configured via `/etc/nginx-ldap-auth.conf` (JSON or YAML)
+- Nginx proxies the `Authorization` header to the daemon; daemon binds to LDAP,
+  checks group membership, returns 200 or 403
+- **The PHP `AdminAuth` layer remains** — it receives `PHP_AUTH_PW` from nginx,
+  can verify the username against LDAP group membership, and establish the PHP session
+
+Nginx config (add to `location ^~ /admin/`):
+
+```nginx
+location ^~ /admin/ {
+    # Replace auth_basic + auth_basic_user_file with:
+    auth_request /auth-ldap;
+    auth_request_set $saved_set_cookie $upstream_http_set_cookie;
+    add_header Set-Cookie $saved_set_cookie;
+
+    # Client-facing Basic Auth challenge (so the browser asks for credentials)
+    satisfy any;
+    # Fallback: if auth_request returns 401, challenge
+    error_page 401 = @ldap_challenge;
+
+    # Keep: rate limiting, CSP, PHP handling, security headers
+    limit_req zone=admin burst=20 nodelay;
+    # ... rest as-is ...
+}
+
+# Internal endpoint — delegates to LDAP daemon
+location = /auth-ldap {
+    internal;
+    proxy_pass http://127.0.0.1:8888;
+    proxy_pass_request_body off;
+    proxy_set_header Content-Length "";
+    proxy_set_header Authorization $http_authorization;
+}
+
+# Trigger browser Basic Auth dialog when LDAP returns 401
+location @ldap_challenge {
+    add_header WWW-Authenticate 'Basic realm="Admin Access - XAMXAM"';
+    return 401;
+}
+```
+
+### Option B — `ngx_http_auth_ldap_module` (native nginx module)
+
+- Requires recompiling nginx with this third-party module
+- Simpler config: `auth_ldap "XAMXAM Admin"; auth_ldap_servers { ... }`
+- Less flexible; harder to debug
+
+### Option C — PHP-only LDAP (no nginx layer)
+
+- Remove nginx auth entirely
+- `AdminAuth::requireLogin()` does `ldap_bind()` + group check directly in PHP
+- Simpler nginx config, but no nginx-level gate
+- Browser auth dialog still possible via PHP sending `WWW-Authenticate` header
+
+## After LDAP is working: cleanup checklist
+
+| Step | File(s) affected | Action |
+|------|-----------------|--------|
+| 1 | `app/src/AdminAuth.php` | Remove `getStoredHash()`, `setPasswordHash()`, `removePasswordHash()`, `hasPassword()`, `verifyHash()`. Keep `requireLogin()`, `isAuthenticated()`, `login()`, `logout()` — adapt them to LDAP group check. |
+| 2 | `app/public/admin/login.php` | Remove entirely (no more PHP login form). |
+| 3 | `app/public/admin/actions/account.php` | Remove entirely (no more password CRUD). |
+| 4 | `app/templates/admin/login.php` | Remove template file. |
+| 5 | `app/templates/admin/parametres.php` | Remove the "Compte administrateur" `<section>` (password set/change/delete UI). |
+| 6 | `app/public/admin/parametres.php` | Remove `AdminAuth::hasPassword()` call and related variables. |
+| 7 | `app/templates/admin/account.php` | Remove if only used for password management. |
+| 8 | `nginx/xamxam.conf` | Remove `auth_basic` and `auth_basic_user_file` lines from the admin location block. |
+| 9 | Database | Remove `admin_password_hash` row from `site_settings` table (manual or migration). |
+| 10 | `app/bootstrap.php` | Remove legacy `ADMIN_PASSWORD_HASH` constant reference if present. |
+
+## Dependencies to install
+
+- **Option A**: Python 3, `python3-ldap` (or `pip install python-ldap`), `nginx-ldap-auth` daemon
+- **Option B**: nginx recompiled with `ngx_http_auth_ldap_module`
+- **Option C**: PHP `ldap` extension (`php8.4-ldap` or `apt install php-ldap`)
+
+## Notes
+
+- The `AdminAuth` PHP layer should remain even after LDAP is implemented — it provides
+  session persistence, logout, CSRF integration, and the admin audit log identity.
+- The LDAP daemon/nginx layer handles **authentication** (who are you?).
+  The PHP `AdminAuth` layer handles **session management** (are you still you?).
+- If IT provides a dedicated admin group, access control is centralised: adding/removing
+  an admin is a single LDAP operation, no need to touch the server.

TODO.md

@@ -98,3 +98,11 @@
 - [x] Update all PHP templates to use new `.btn` classes (`btn btn--primary`, `btn btn--secondary`, `btn btn--danger`, etc.)
 - [x] Update border-radius on pagination buttons to 10px for consistency
 - [x] Exclude `storage/maintenance.flag` from rsync deploy and git
+
+## Admin file export system
+- [x] `ExportController`: add `getAllThesisFiles()`, `buildExportManifest()`, `createExportZip()` — gathers all thesis files, creates zip with files/ + manifest.json
+- [x] `admin/actions/export-files.php` — thin dispatcher, streams zip, logs audit
+- [x] `AdminLogger::logFilesExport()` — audit log entry for file exports
+- [x] `templates/admin/index.php` — add "Exporter fichiers" button next to CSV export button
+- [x] `Database::getAllThesisFilesForExport()` — query all thesis_files + identifier
+- [x] `docs/export.md` — documentation en français pour administrateurs : fonctionnement, contenu du ZIP, procédure de restauration complète et partielle

app/public/admin/actions/export-files.php

@@ -0,0 +1,48 @@
+<?php
+/**
+ * Export all thesis files as a ZIP archive.
+ *
+ * The ZIP contains:
+ *   - manifest.json   — maps every thesis to its files with DB-relevant metadata
+ *   - files/           — mirror of storage/theses/ directory structure
+ *
+ * Thin dispatcher — delegates all data assembly to ExportController,
+ * then streams the response.
+ */
+require_once __DIR__ . "/../../../bootstrap.php";
+require_once __DIR__ . '/../../../src/AdminAuth.php';
+AdminAuth::requireLogin();
+
+require_once APP_ROOT . '/src/Controllers/ExportController.php';
+require_once APP_ROOT . '/src/AdminLogger.php';
+
+try {
+    $controller = ExportController::create();
+
+    // Build the zip
+    $zipPath = $controller->createExportZip();
+
+    $fileSize = filesize($zipPath);
+    $fileCount = count($controller->getAllThesisFiles());
+
+    // Audit log (before headers in case log fails — but it's best-effort anyway)
+    AdminLogger::make()->logFilesExport($fileCount, (int)$fileSize);
+
+    $filename = 'xamxam-files-' . date('Y-m-d') . '.zip';
+
+    header('Content-Type: application/zip');
+    header('Content-Disposition: attachment; filename="' . $filename . '"');
+    header('Content-Length: ' . $fileSize);
+    header('Cache-Control: no-cache, must-revalidate');
+
+    readfile($zipPath);
+
+    // Clean up temp file
+    @unlink($zipPath);
+} catch (Exception $e) {
+    error_log('Files export error: ' . $e->getMessage());
+    http_response_code(500);
+    exit('Erreur lors de la création de l\'archive : ' . htmlspecialchars($e->getMessage()));
+}
+
+exit;

app/src/AdminLogger.php

@@ -185,6 +185,15 @@ class AdminLogger
         $this->write('system', 'db_export', 'success');
     }
 
+    /** Files export (ZIP with all thesis files + manifest) */
+    public function logFilesExport(int $fileCount, int $byteSize): void
+    {
+        $this->write('system', 'files_export', 'success', [
+            'file_count' => $fileCount,
+            'byte_size'  => $byteSize,
+        ]);
+    }
+
     /** Parametres: delete all TFEs */
     public function logDeleteAllTheses(int $count): void
     {

app/src/Controllers/ExportController.php

@@ -37,6 +37,146 @@ class ExportController
         return $this->db->getDatabasePath();
     }
 
+    // ── Files export ────────────────────────────────────────────────────
+
+    /**
+     * Fetch all thesis file records with their thesis identifier.
+     *
+     * @return list<array{id:int, thesis_id:int, identifier:?string, file_type:string,
+     *                    file_path:string, file_name:string, file_size:?int,
+     *                    mime_type:?string, description:?string, sort_order:int,
+     *                    display_label:?string, file_hash:?string}>
+     */
+    public function getAllThesisFiles(): array
+    {
+        return $this->db->getAllThesisFilesForExport();
+    }
+
+    /**
+     * Build a JSON manifest describing every thesis and its files.
+     *
+     * The manifest maps identifier → { title, files: [{type, path, name, size, mime, hash, label}] }
+     * and is used on restore to re-link files to DB records.
+     *
+     * @return array
+     */
+    public function buildExportManifest(): array
+    {
+        $files   = $this->getAllThesisFiles();
+        $theses  = $this->db->getAllThesesForExport();
+
+        // Index theses by id for O(1) lookup
+        $byId = [];
+        foreach ($theses as $t) {
+            $byId[(int) $t['id']] = $t;
+        }
+
+        $entries = [];
+        foreach ($files as $f) {
+            $tid = (int) $f['thesis_id'];
+            $t   = $byId[$tid] ?? null;
+            $key = $t['identifier'] ?? ('id_' . $tid);
+
+            if (!isset($entries[$key])) {
+                $entries[$key] = [
+                    'id'         => $tid,
+                    'identifier' => $t['identifier'] ?? null,
+                    'title'      => $t['title']      ?? '(inconnu)',
+                    'year'       => $t['year']       ?? 0,
+                    'files'      => [],
+                ];
+            }
+
+            $entries[$key]['files'][] = [
+                'type'      => $f['file_type'],
+                'path'      => $f['file_path'],
+                'name'      => $f['file_name'],
+                'size'      => $f['file_size'],
+                'mime'      => $f['mime_type'],
+                'hash'      => $f['file_hash'] ?? null,
+                'label'     => $f['display_label'] ?? null,
+                'sort_order' => (int) $f['sort_order'],
+            ];
+        }
+
+        return [
+            'exported_at' => date('c'),
+            'db_file'     => basename($this->db->getDatabasePath()),
+            'total_theses' => count($entries),
+            'total_files'  => count($files),
+            'theses'       => $entries,
+        ];
+    }
+
+    /**
+     * Create a zip archive containing all thesis files under a files/
+     * directory and a manifest.json at the root.
+     *
+     * Returns the path to the temporary zip file. Caller is responsible
+     * for unlink() after streaming.
+     *
+     * @param  string|null $baseDir  Base directory path for files inside the zip.
+     *                               Defaults to "files" (so files are at "files/theses/...").
+     * @return string Absolute path to the generated zip file.
+     * @throws Exception if zip creation fails.
+     */
+    public function createExportZip(?string $baseDir = null): string
+    {
+        $baseDir = $baseDir ?? 'files';
+        $storageRoot = defined('STORAGE_ROOT') ? STORAGE_ROOT : APP_ROOT . '/storage';
+        $files = $this->getAllThesisFiles();
+        $manifest = $this->buildExportManifest();
+
+        $tmpPath = tempnam(sys_get_temp_dir(), 'xamxam-export-');
+        if ($tmpPath === false) {
+            throw new Exception('Impossible de créer un fichier temporaire.');
+        }
+
+        // tempnam creates a regular file; we want a .zip file instead.
+        unlink($tmpPath);
+        $tmpPath .= '.zip';
+
+        $zip = new ZipArchive();
+        if ($zip->open($tmpPath, ZipArchive::CREATE | ZipArchive::OVERWRITE) !== true) {
+            throw new Exception('Impossible de créer l\'archive ZIP.');
+        }
+
+        // Add manifest.json at the root
+        $zip->addFromString(
+            'manifest.json',
+            json_encode($manifest, JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE | JSON_PRETTY_PRINT)
+        );
+
+        // Add every thesis file under files/
+        $addedCount   = 0;
+        $skippedCount = 0;
+        foreach ($files as $f) {
+            $fullPath = $storageRoot . '/' . $f['file_path'];
+            if (!is_file($fullPath) || !is_readable($fullPath)) {
+                $skippedCount++;
+                continue;
+            }
+            $zipPath = $baseDir . '/' . $f['file_path'];
+            $zip->addFile($fullPath, $zipPath);
+            $addedCount++;
+        }
+
+        $zip->addFromString(
+            'manifest.json',
+            json_encode(array_merge($manifest, [
+                'zip_skipped_count' => $skippedCount,
+                'zip_added_count'   => $addedCount,
+            ]), JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE | JSON_PRETTY_PRINT)
+        );
+
+        if (!$zip->close()) {
+            @unlink($tmpPath);
+            throw new Exception('Erreur lors de la finalisation de l\'archive ZIP.');
+        }
+
+        return $tmpPath;
+    }
+
     // ── CSV export ───────────────────────────────────────────────────────
 
     /**
@@ -76,7 +216,7 @@ class ExportController
      */
     public function exportAllTheses(): array
     {
-        // 1) Base thesis data
+        // 1) Base thesis data (includes license_name via migration; fallback to license_type from the view)
         $theses = $this->db->getAllThesesForExport();
         if ($theses === []) {
             return [];

app/src/Database.php

@@ -2188,6 +2188,21 @@ class Database
         ')->fetchAll();
     }
 
+    /**
+     * All thesis files for the file-export ZIP.
+     * Includes every thesis_files column + the thesis identifier for manifest
+     * construction.
+     */
+    public function getAllThesisFilesForExport(): array
+    {
+        return $this->pdo->query('
+            SELECT tf.*, t.identifier
+            FROM thesis_files tf
+            JOIN theses t ON t.id = tf.thesis_id
+            ORDER BY t.year DESC, t.title ASC, tf.sort_order ASC
+        ')->fetchAll();
+    }
+
     // ========================================================================
     // SINGLETON PATTERN ENFORCEMENT
     // ========================================================================

app/templates/admin/index.php

@@ -134,6 +134,9 @@ document.addEventListener('DOMContentLoaded', () => {
             <a href="/admin/actions/export-csv.php" class="btn btn--primary btn--sm">
                 Exporter CSV
             </a>
+            <a href="/admin/actions/export-files.php" class="btn btn--primary btn--sm">
+                Exporter fichiers
+            </a>
         </div>
     </div>
 

docs/export.md

@@ -0,0 +1,197 @@
+# Export et sauvegarde des données XAMXAM
+
+Ce document explique le fonctionnement du système d'export pour les
+administrateur·ices de la plateforme. Il couvre les trois types d'export
+disponibles depuis le panneau d'administration, la manière de les combiner
+pour une restauration complète, et les détails techniques utiles en cas de
+problème.
+
+---
+
+## Les trois exports disponibles
+
+Depuis la page principale d'administration (`/admin/`), la barre d'outils
+propose trois boutons d'export :
+
+| Bouton | Fichier produit | Contenu |
+|---|---|---|
+| **Exporter CSV** | `xamxam-export-AAAA-MM-JJ.csv` | Liste complète des TFE au format compatible avec l'import CSV |
+| **Exporter DB** | `xamxam-db-AAAA-MM-JJ.sqlite` | Copie brute du fichier de base de données SQLite |
+| **Exporter fichiers** | `xamxam-files-AAAA-MM-JJ.zip` | Archive ZIP contenant tous les fichiers attachés aux TFE + un manifeste JSON |
+
+---
+
+## Exporter les fichiers (ZIP)
+
+### Ce que contient l'archive
+
+```
+xamxam-files-2026-05-07.zip
+├── manifest.json        ← métadonnées de chaque TFE et ses fichiers
+└── files/
+    └── theses/
+        ├── 2025/
+        │   ├── 2025_EMMA_RENARD/
+        │   │   └── EMMA_RENARD_carte_loire_a_velo_france.pdf
+        │   ├── 2025_LILA_DUBOIS_KARIM_NASSAR/
+        │   │   ├── nixing_the_fix_report_final.pdf
+        │   │   ├── bbb_sunflower_1080p_30fps_normal_mp4.zip
+        │   │   └── carte_loire_a_velo_france.pdf
+        │   └── …
+        └── 2026/
+            └── …
+```
+
+### Le fichier `manifest.json`
+
+```json
+{
+  "exported_at": "2026-05-07T15:30:00+02:00",
+  "db_file": "xamxam.db",
+  "total_theses": 140,
+  "total_files": 312,
+  "zip_added_count": 310,
+  "zip_skipped_count": 2,
+  "theses": {
+    "2025-003": {
+      "id": 42,
+      "identifier": "2025-003",
+      "title": "Titre du TFE",
+      "year": 2025,
+      "files": [
+        {
+          "type": "main",
+          "path": "theses/2025/2025_AUTEUR/mon_fichier.pdf",
+          "name": "mon_fichier.pdf",
+          "size": 1234567,
+          "mime": "application/pdf",
+          "hash": null,
+          "label": "Mémoire principal",
+          "sort_order": 1
+        }
+      ]
+    }
+  }
+}
+```
+
+Le manifeste fait le **pont entre la base de données et les fichiers**. Chaque
+TFE est indexé par son identifiant (ex. `2025-003`), ce qui permet de
+retrouver ses fichiers même si l'ordre des IDs change après une restauration.
+
+---
+
+## Restaurer une sauvegarde complète
+
+Une sauvegarde complète se compose de **trois fichiers** à exporter le même
+jour (DB + fichiers ZIP + CSV). Voici la procédure de restauration sur un
+serveur neuf ou après un incident.
+
+### 1. Restaurer la base de données
+
+```bash
+# Arrêter le serveur web
+sudo systemctl stop nginx
+
+# Remplacer le fichier SQLite
+cp xamxam-db-AAAA-MM-JJ.sqlite /var/www/xamxam/storage/xamxam.db
+chown www-data:www-data /var/www/xamxam/storage/xamxam.db
+chmod 640 /var/www/xamxam/storage/xamxam.db
+```
+
+### 2. Restaurer les fichiers
+
+```bash
+# Décompresser l'archive dans le répertoire storage/
+# ATTENTION : le zip contient un dossier files/ à la racine.
+# On le décompresse dans /tmp puis on copie le contenu de files/theses/
+# dans storage/theses/ pour préserver la structure existante.
+
+unzip xamxam-files-AAAA-MM-JJ.zip -d /tmp/xamxam-restore
+cp -r /tmp/xamxam-restore/files/theses/* /var/www/xamxam/storage/theses/
+chown -R www-data:www-data /var/www/xamxam/storage/theses/
+rm -rf /tmp/xamxam-restore
+```
+
+> **Pourquoi ça fonctionne :** les chemins dans la table `thesis_files` sont
+> relatifs (ex. `theses/2025/2025_AUTEUR/fichier.pdf`). En restaurant les
+> fichiers au même emplacement sous `storage/`, les liens DB ↔ fichiers sont
+> automatiquement rétablis.
+
+### 3. Redémarrer
+
+```bash
+sudo systemctl start nginx
+```
+
+### 4. Vérifier
+
+Naviguer vers `/admin/` et vérifier que la liste des TFE s'affiche
+correctement et que les fichiers sont téléchargeables.
+
+---
+
+## Restauration partielle ou re-linkage
+
+Si la base de données a été perdue mais que vous avez le ZIP des fichiers
+et le CSV d'export, vous pouvez reconstruire les liens grâce au
+`manifest.json` :
+
+1. **Réimporter le CSV** via l'interface d'administration (bouton *Importer un
+   CSV*). Les identifiants (colonne `Identifiant`) doivent correspondre à ceux
+   du manifeste.
+
+2. **Décompresser le ZIP** dans `storage/` comme décrit ci-dessus.
+
+3. **Vérifier avec le manifeste** — les chemins dans `manifest.json`
+   correspondent aux chemins dans `thesis_files.file_path`. Si les
+   identifiants du CSV et ceux du manifeste coïncident, les fichiers seront
+   correctement liés après l'import.
+
+---
+
+## Détails techniques
+
+### Performance
+
+L'export des fichiers utilise `ZipArchive` (extension PHP standard) et crée
+une archive temporaire dans `/tmp`. Pour un volume important de fichiers
+(plusieurs centaines), la création peut prendre quelques secondes. Un timeout
+d'exécution raisonnable (`max_execution_time ≥ 60s`) est recommandé.
+
+### Sécurité
+
+- Les exports sont **protégés par authentification administrateur**
+  (`AdminAuth::requireLogin()`).
+- L'export DB et l'export fichiers sont journalisés dans le log d'audit
+  (`admin_audit_log`) avec l'IP et l'User-Agent de l'administrateur.
+- Les fichiers temporaires sont supprimés après envoi (`unlink()` dans le
+  bloc `finally` implicite de `export-files.php`).
+- Les fichiers dans le ZIP conservent leurs chemins relatifs d'origine — il
+  n'y a pas de risque de *path traversal* car les chemins proviennent de la
+  base de données et ne contiennent jamais `../`.
+
+### Colonnes du CSV d'export
+
+Le CSV utilise la même structure que l'import (21 colonnes). Il est
+directement ré-importable sans modification. Voir [`docs/import.md`](import.md)
+pour le détail des colonnes.
+
+---
+
+## Résumé des commandes utiles
+
+```bash
+# Télécharger les trois exports (depuis le navigateur ou curl)
+curl -u admin:password -O https://xamxam.erg.be/admin/actions/export-db.php
+curl -u admin:password -O https://xamxam.erg.be/admin/actions/export-csv.php
+curl -u admin:password -O https://xamxam.erg.be/admin/actions/export-files.php
+
+# Restauration complète
+sudo systemctl stop nginx
+cp xamxam-db-*.sqlite /var/www/xamxam/storage/xamxam.db
+unzip xamxam-files-*.zip -d /tmp/xamxam-restore
+cp -r /tmp/xamxam-restore/files/theses/* /var/www/xamxam/storage/theses/
+chown -R www-data:www-data /var/www/xamxam/storage/
+sudo systemctl start nginx
+```