Public project creation and admin permissions (#210)

* Add a @requires_admin decorator

It can be used to protect specific endpoints with ADMIN_PASSWORD
(a password that is stored unencrypted in the settings)
The decorator has no effect if ADMIN_PASSWORD is an empty string (default value)

* Require admin permissions to access create project endpoint

When ADMIN_PASSWORD is not empty, project creation form on the
home page will be replaced by a link to the create project endpoint
so one is able to enter the admin password before filling the form

budget/default_settings.py

@@ -10,3 +10,5 @@ SECRET_KEY = "tralala"
 MAIL_DEFAULT_SENDER = ("Budget manager", "budget@notmyidea.org")
 
 ACTIVATE_DEMO_PROJECT = True
+
+ADMIN_PASSWORD = ""

budget/forms.py

@@ -83,6 +83,11 @@ class AuthenticationForm(FlaskForm):
     submit = SubmitField(_("Get in"))
 
 
+class AdminAuthenticationForm(FlaskForm):
+    admin_password = PasswordField(_("Admin password"), validators=[Required()])
+    submit = SubmitField(_("Get in"))
+
+
 class PasswordReminder(FlaskForm):
     id = StringField(_("Project identifier"), validators=[Required()])
     submit = SubmitField(_("Send me the code by email"))

budget/templates/authenticate.html

@@ -7,7 +7,13 @@
 to") }} <a href="{{ url_for(".create_project", project_id=create_project) }}">{{ _("create it") }}</a>{{ _("?") }}
 </p>
 {% endif %}
+{% if admin_auth %}
+<form class="form-horizontal" method="POST" accept-charset="utf-8">
+    {{ forms.admin(form) }}
+</form>
+{% else %}
 <form class="form-horizontal" method="POST" accept-charset="utf-8">
     {{ forms.authenticate(form) }}
 </form>
+{% endif %}
 {% endblock %}

budget/templates/forms.html

@@ -45,6 +45,16 @@
 
 {% endmacro %}
 
+{% macro admin(form) %}
+
+    {% include "display_errors.html" %}
+
+    {{ form.hidden_tag() }}
+    {{ input(form.admin_password) }}
+    {{ submit(form.submit) }}
+
+{% endmacro %}
+
 {% macro create_project(form, home=False) %}
 
     {% include "display_errors.html" %}

budget/templates/home.html

@@ -28,6 +28,9 @@
             </form>
         </div>
         <div class="col-3 offset-md-1">
+            {% if is_admin_mode_enabled %}
+            <a href="{{ url_for(".create_project") }}">...{{ _("or create a new one") }}</a>
+            {% else %}
             <form id="creation-form" class="form-horizontal" action="{{ url_for(".create_project") }}" method="post">
                 <fieldset class="form-group">
                     <legend>...{{ _("or create a new one") }}</legend>
@@ -37,6 +40,7 @@
                     <button class="btn" type="submit">{{ _("let's get started") }}</button>
                 </div>
             </form>
+            {% endif %}
         </main>
     </div>
 {% endblock %}

budget/tests/tests.py

@@ -44,6 +44,8 @@ class TestCase(unittest.TestCase):
         # clean after testing
         models.db.session.remove()
         models.db.drop_all()
+        # reconfigure app with default settings
+        run.configure()
 
     def login(self, project, password=None, test_client=None):
         password = password or project
@@ -373,6 +375,25 @@ class BudgetTestCase(TestCase):
             c.get("/exit")
             self.assertNotIn('raclette', session)
 
+    def test_admin_authentication(self):
+        run.app.config['ADMIN_PASSWORD'] = "pass"
+
+        # test the redirection to the authentication page when trying to access admin endpoints
+        resp = self.app.get("/create")
+        self.assertIn('<a href="/admin?goto=%2Fcreate">', resp.data.decode('utf-8'))
+
+        # test right password
+        resp = self.app.post("/admin?goto=%2Fcreate", data={'admin_password': 'pass'})
+        self.assertIn('<a href="/create">/create</a>', resp.data.decode('utf-8'))
+
+        # test wrong password
+        resp = self.app.post("/admin?goto=%2Fcreate", data={'admin_password': 'wrong'})
+        self.assertNotIn('<a href="/create">/create</a>', resp.data.decode('utf-8'))
+
+        # test empty password
+        resp = self.app.post("/admin?goto=%2Fcreate", data={'admin_password': ''})
+        self.assertNotIn('<a href="/create">/create</a>', resp.data.decode('utf-8'))
+
     def test_manage_bills(self):
         self.post_project("raclette")
 

budget/translations/fr/LC_MESSAGES/messages.po

@@ -41,6 +41,10 @@ msgstr "Email"
 msgid "Project identifier"
 msgstr "Identifiant du projet"
 
+#: forms.py:87
+msgid "Admin password"
+msgstr "Mot de passe administrateur"
+
 #: forms.py:87 templates/send_invites.html:5
 msgid "Create the project"
 msgstr "Créer le projet"
@@ -158,6 +162,10 @@ msgstr "remboursements"
 msgid "Export file format"
 msgstr "Format du fichier d'export"
 
+#: web.py:95
+msgid "This admin password is not the right one"
+msgstr "Le mot de passe administrateur que vous avez entré n'est pas correct"
+
 #: web.py:95
 msgid "This private code is not the right one"
 msgstr "Le code que vous avez entré n'est pas correct"

budget/web.py

@@ -16,11 +16,12 @@ from flask_babel import get_locale, gettext as _
 from smtplib import SMTPRecipientsRefused
 import werkzeug
 from sqlalchemy import orm
+from functools import wraps
 
 # local modules
 from models import db, Project, Person, Bill
-from forms import AuthenticationForm, EditProjectForm, InviteForm, \
-    MemberForm, PasswordReminder, ProjectForm, get_billform_for, \
+from forms import AdminAuthenticationForm, AuthenticationForm, EditProjectForm, \
+    InviteForm, MemberForm, PasswordReminder, ProjectForm, get_billform_for, \
     ExportForm
 from utils import Redirect303, list_of_dicts2json, list_of_dicts2csv
 
@@ -28,6 +29,19 @@ main = Blueprint("main", __name__)
 mail = Mail()
 
 
+def requires_admin(f):
+    """Require admin permissions for @requires_admin decorated endpoints.
+       Has no effect if ADMIN_PASSWORD is empty (default value)
+    """
+    @wraps(f)
+    def admin_auth(*args, **kws):
+        admin_password = session.get('admin_password', '')
+        if not admin_password == current_app.config['ADMIN_PASSWORD']:
+            raise Redirect303(url_for('.admin', goto=request.path))
+        return f(*args, **kws)
+    return admin_auth
+
+
 @main.url_defaults
 def add_project_id(endpoint, values):
     """Add the project id to the url calls if it is expected.
@@ -66,6 +80,23 @@ def pull_project(endpoint, values):
                     url_for(".authenticate", project_id=project_id))
 
 
+@main.route("/admin", methods=["GET", "POST"])
+def admin():
+    """Admin authentication"""
+    form = AdminAuthenticationForm()
+    goto = request.args.get('goto', url_for('.home'))
+    if request.method == "POST":
+        if form.validate():
+            if form.admin_password.data == current_app.config['ADMIN_PASSWORD']:
+                session['admin_password'] = form.admin_password.data
+                session.update()
+                return redirect(goto)
+            else:
+                msg = _("This admin password is not the right one")
+                form.errors['admin_password'] = [msg]
+    return render_template("authenticate.html", form=form, admin_auth=True)
+
+
 @main.route("/authenticate", methods=["GET", "POST"])
 def authenticate(project_id=None):
     """Authentication form"""
@@ -121,14 +152,18 @@ def authenticate(project_id=None):
 def home():
     project_form = ProjectForm()
     auth_form = AuthenticationForm()
+    # If ADMIN_PASSWORD is empty we consider that admin mode is disabled
+    is_admin_mode_enabled = bool(current_app.config['ADMIN_PASSWORD'])
     is_demo_project_activated = current_app.config['ACTIVATE_DEMO_PROJECT']
 
     return render_template("home.html", project_form=project_form,
                            is_demo_project_activated=is_demo_project_activated,
+                           is_admin_mode_enabled=is_admin_mode_enabled,
                            auth_form=auth_form, session=session)
 
 
 @main.route("/create", methods=["GET", "POST"])
+@requires_admin
 def create_project():
     form = ProjectForm()
     if request.method == "GET" and 'project_id' in request.values: