Changement du refresh handler, soft reset d'ajouter sur beaucoup de formulaire de modification

app/app.py

@@ -26,8 +26,10 @@ from sqlalchemy import text
 from werkzeug.exceptions import HTTPException
 
 from app import i18n
+from app.api import json_endpoint
 from app.extensions import babel, csrf, db, limiter, login_manager
 from app.pagination import page_url
+from app.responders import current_revision, is_ajax_submit
 
 load_dotenv()
 
@@ -347,6 +349,42 @@ def create_app(config=None):
         response.headers['X-Request-Id'] = g.get('request_id', '-')
         return response
 
+    @app.before_request
+    def reject_stale_ajax_write():
+        """Reject an AJAX edit whose view is stale, instead of overwriting.
+
+        The AJAX form handler in main.js sends the revision it last saw in the
+        X-Revision header. If another client has committed since then the
+        server's revision has moved on, and clobbering their change would be
+        silent last-write-wins. Answer 409 so the client asks the user to
+        reload the page first.
+        """
+        if request.method != 'POST':
+            return None
+        if not is_ajax_submit():
+            return None
+        sent = request.headers.get('X-Revision')
+        if sent is None:
+            return None
+        try:
+            sent = int(sent)
+        except (TypeError, ValueError):
+            return None
+        if sent != current_revision():
+            return (
+                jsonify(
+                    {
+                        'error': 'conflict',
+                        'message': _(
+                            'This page was changed by someone else. Reload to '
+                            'see the latest changes before saving.'
+                        ),
+                    }
+                ),
+                409,
+            )
+        return None
+
     @app.url_defaults
     def version_static_urls(endpoint, values):
         """Stamp every static URL with the file's modification time.
@@ -403,6 +441,7 @@ def create_app(config=None):
 
     configure_logging(app)
 
+    from app.routes.admin import admin_bp
     from app.routes.auth import auth_bp
     from app.routes.evaluations import evaluations_bp
     from app.routes.main import main_bp
@@ -411,7 +450,6 @@ def create_app(config=None):
     from app.routes.teams import teams_bp
     from app.routes.tryouts import tryouts_bp
     from app.routes.users import users_bp
-    from app.routes.admin import admin_bp
 
     app.register_blueprint(auth_bp)
     app.register_blueprint(tryouts_bp)
@@ -531,6 +569,18 @@ def create_app(config=None):
 
         return jsonify(health_data), 200
 
+    @app.route('/api/revision')
+    @json_endpoint
+    def data_revision():
+        """The current dataset revision, for the AJAX form handler in main.js.
+
+        One primary-key lookup in app_settings. The client compares this with
+        the revision it last saw to decide whether a focus refresh is needed,
+        and sends it back with every AJAX mutation so a stale edit is rejected
+        with a 409 instead of overwriting someone else's change.
+        """
+        return jsonify({'revision': current_revision()})
+
     # =========================================================================
     # Custom Error Handlers
     # =========================================================================
@@ -725,4 +775,4 @@ def create_app(config=None):
 # own host, port and debug default — `python app/app.py` bound 0.0.0.0:10000
 # while `python run.py` bound 127.0.0.2:5000 with the debugger on. This
 # module defines the factory; run.py starts it for development, wsgi.py for
-# production (ARCH-007).
+# production (ARCH-007).