reset branch commit history

admin/admin.py

@@ -1,12 +1,21 @@
 #!/usr/bin/env python3
 
 __copyright__ = "Copyright (c) 2024, Utrecht University"
-__license__   = "GPLv3, see LICENSE"
+__license__ = "GPLv3, see LICENSE"
 
-from flask import abort, Blueprint, render_template, Response
+import json
+from functools import wraps
+from os import path
+
+from flask import (
+    abort, Blueprint, current_app as app, flash, g, redirect,
+    render_template, request, Response, url_for
+)
+from markupsafe import escape
 
 import api
 
+# Blueprint configuration
 admin_bp = Blueprint("admin_bp", __name__,
                      template_folder="templates/admin",
                      static_folder="static/admin",
@@ -15,10 +24,87 @@
 
 @admin_bp.route("/")
 def index() -> Response:
-    """Route to the admin page, if user has admin access"""
+    """Route to the admin page, if user has admin access."""
     has_admin_access = api.call("admin_has_access", data={})["data"]
 
     if has_admin_access:
         return render_template("admin.html")
     else:
         return abort(403)
+
+
+def admin_required(f):
+    """Decorator to check if the user has admin privileges."""
+    @wraps(f)
+    def decorated_function(*args, **kwargs):
+        if not getattr(g, 'admin', False):
+            flash('You do not have permission to perform this action.', 'danger')
+            return redirect(url_for('admin_bp.index'))
+        return f(*args, **kwargs)
+    return decorated_function
+
+
+@admin_bp.route('/set_banner', methods=['POST'])
+@admin_required
+def set_banner():
+    """Set the banner message and persist it to configuration files."""
+    banner_message = request.form.get('banner', '').strip()
+    banner_message = escape_html(banner_message)  # Ensure safe text
+
+    # Message length check
+    error_message, is_valid = length_check(banner_message)
+    if not is_valid:
+        flash(error_message, "danger")
+        return redirect(url_for('admin_bp.index'))
+
+    # Update app config settings and save settings
+    settings = {
+        'banner_enabled': True,
+        'banner_importance': 'importance' in request.form,
+        'banner_message': banner_message
+    }
+    flash_msg = 'Set banner message successfully'
+    return save_settings(settings, flash_msg)
+
+
+@admin_bp.route('/remove_banner', methods=['POST'])
+@admin_required
+def remove_banner():
+    """Remove banner message and save settings to web server's config files."""
+    settings = {
+        'banner_enabled': False,
+        'banner_importance': False,
+        'banner_message': ''
+    }
+    flash_msg = 'Banner removed successfully'
+    return save_settings(settings, flash_msg)
+
+
+def length_check(banner_message):
+    """Validate the length and content of the banner message."""
+    max_length = 256
+    if not banner_message:
+        return "Empty banner message found.", False
+    elif len(banner_message) > max_length:
+        return "Banner message too long.", False
+    return None, True
+
+
+def escape_html(text):
+    """Escape HTML special characters in text."""
+    return escape(text)
+
+
+def save_settings(settings, flash_msg):
+    """Apply and save the given settings to the configuration file."""
+    config_file_path = path.join(app.config['APP_SHARED_FOLDER'], 'banner_settings.json')
+    app.config.update(settings)
+    try:
+        with open(config_file_path, 'w') as file:
+            json.dump(settings, file)
+        flash(flash_msg, 'success')
+    except IOError as e:
+        flash(f"Failed to save settings: {str(e)}", "danger")
+        return f"Failed to save settings: {e}", 500
+
+    return redirect(url_for('admin_bp.index'))

admin/templates/admin/admin.html

@@ -3,9 +3,34 @@
 {% block title %}{{ super() }} ‐ Administration{% endblock title %}
 
 {% block content %}
-<h1>Administration</h1>
-
-<div class="card">
-    <p>This is a blank admin page, feature development is on the way ...</p>
+<div class="container mt-4">
+    <header>
+        <h1>Administration</h1>
+    </header>
+    <main>
+        <section class="card my-3">
+            <div class="card-body">
+                <h2 class="card-title">Set maintenance banner</h2>
+                <div class="d-flex justify-content-start align-items-end" style="width: 100%;">
+                    <form action="{{ url_for('admin_bp.set_banner') }}" method="POST" class="flex-fill me-2 needs-validation" novalidate>
+                        <input type="hidden" name="csrf_token" value="{{ csrf_token() }}">
+                        <div class="mb-3">
+                            <label for="banner">Banner Details:</label>
+                            <textarea class="form-control" name="banner" id="banner" placeholder="Enter system maintenance details..." required></textarea>
+                        </div>
+                        <div class="mb-3 form-check">
+                            <input type="checkbox" class="form-check-input" id="importance" name="importance">
+                            <label class="form-check-label" for="importance">Mark as Important</label>
+                        </div>
+                        <button type="submit" class="btn btn-primary">Set Banner</button>
+                    </form>
+                    <form action="{{ url_for('admin_bp.remove_banner') }}" method="POST" class="flex-shrink-1">
+                        <input type="hidden" name="csrf_token" value="{{ csrf_token() }}">
+                        <button type="submit" class="btn btn-secondary">Remove Banner</button>
+                    </form>
+                </div>
+            </div>
+        </section>
+    </main>
 </div>
 {% endblock content %}

app.py

@@ -3,6 +3,7 @@
 __copyright__ = 'Copyright (c) 2021-2023, Utrecht University'
 __license__   = 'GPLv3, see LICENSE'
 
+import json
 from os import path
 from typing import Dict, Optional
 
@@ -43,6 +44,33 @@
 ])
 app.jinja_loader = theme_loader
 
+
+# Load banner configurations
+def load_banner_config():
+    '''Load or initialize banner configurations.'''
+    config_file_path = path.join(app.config['APP_SHARED_FOLDER'], 'banner_settings.json')
+    default_config = {'banner_enabled': False}
+
+    try:
+        if not path.exists(config_file_path):
+            return default_config
+
+        with open(config_file_path, 'r') as file:
+            settings = json.load(file)
+            return {
+                'banner_enabled': settings.get('banner_enabled', False),
+                'banner_importance': settings.get('banner_importance', False),
+                'banner_message': settings.get('banner_message', '')
+            }
+    except json.JSONDecodeError:
+        return default_config
+    except Exception:
+        return default_config
+
+
+app.config['APP_SHARED_FOLDER'] = '/tmp'
+app.config.update(load_banner_config())
+
 # Setup values for the navigation bar used in
 # general/templates/general/base.html
 app.config['modules'] = []

general/templates/general/banner.html

@@ -0,0 +1,3 @@
+<div class="non-production sticky-top text-center fw-bold lh-1 p-1 {{ 'text-bg-danger' if config.banner_importance else 'text-bg-primary' }}" role="alert">
+    {{ config.get('banner_message', 'Default banner message if none provided.') }}
+</div>

general/templates/general/base.html

@@ -44,6 +44,7 @@
 
     <body class="d-flex flex-column min-vh-100">
         {% if config.get('YODA_ENVIRONMENT') != "production" %}{% include 'environment.html' %}{% endif %}
+        {% if config.get('banner_enabled') %}{% include 'banner.html' %}{% endif %}
         <header class="py-3">
             <div class="container">
                 <div class="row">