More elegant error handling

ref-test/app/admin/views.py

@@ -1,7 +1,7 @@
 from ..forms.admin import AddTimeAdjustment, CreateTest, CreateUser, DeleteUser, Login, Register, ResetPassword, UpdatePassword, UpdateUser, UploadData
 from ..models import Dataset, Entry, Test, User
 from ..tools.auth import disable_if_logged_in, require_account_creation
-from ..tools.forms import get_dataset_choices, get_time_options
+from ..tools.forms import get_dataset_choices, get_time_options, send_errors_to_client
 from ..tools.data import check_is_json, validate_json
 from ..tools.test import  answer_options, get_correct_answers
 
@@ -61,8 +61,7 @@ def _login():
                     return jsonify({'success': f'Successfully logged in.'}), 200
                 return jsonify({'error': f'The password you entered is incorrect.'}), 401
             return jsonify({'error': f'The username you entered does not exist.'}), 401
-        errors = [*form.username.errors, *form.password.errors]
-        return jsonify({ 'error': errors}), 400
+        return send_errors_to_client(form=form)
     if 'remembered_username' in session: form.username.data = session.pop('remembered_username')
     next = request.args.get('next')
     return render_template('/admin/auth/login.html', form=form, next=next)
@@ -90,8 +89,7 @@ def _register():
                 return jsonify({'success': message}), 200
             flash(message=message, category='error')
             return jsonify({'error': message}), 401
-        errors = [*form.username.errors, *form.email.errors, *form.password.errors, *form.password_reenter.errors]
-        return jsonify({ 'error': errors}), 400
+        return send_errors_to_client(form=form)
     return render_template('admin/auth/register.html', form=form)
 
 @admin.route('/reset/', methods=['GET','POST'])
@@ -108,8 +106,7 @@ def _reset():
             if not user: return jsonify({'error': 'The user account does not exist.'}), 400
             if not user.get_email() == request.form.get('email'): return jsonify({'error': 'The email address does not match the user account.'}), 400
             return user.reset_password()
-        errors = [*form.username.errors, *form.email.errors]
-        return jsonify({ 'error': errors}), 400
+        return send_errors_to_client(form=form)
     
     token = request.args.get('token')
     if token:
@@ -134,8 +131,7 @@ def _update_password():
         session['remembered_username'] = user.get_username()
         flash('Your password has been reset.', 'success')
         return jsonify({'success':'Your password has been reset'}), 200
-    errors = [*form.password.errors, *form.password_reenter.errors]
-    return jsonify({ 'error': errors}), 401
+    return send_errors_to_client(form=form)
 
 @admin.route('/settings/users/', methods=['GET', 'POST'])
 @login_required
@@ -152,8 +148,7 @@ def _users():
             success, message = new_user.register(notify=request.form.get('notify'), password=password)
             if success: return jsonify({'success': message}), 200
             return jsonify({'error': message}), 401
-        errors = [*form.username.errors, *form.email.errors, *form.password.errors]
-        return jsonify({ 'error': errors}), 401
+        return send_errors_to_client(form=form)
     return render_template('/admin/settings/users.html', form = form, users = users)
 
 @admin.route('/settings/users/delete/<string:id>', methods=['GET', 'POST'])
@@ -170,8 +165,7 @@ def _delete_user(id:str):
             success, message = user.delete(notify=request.form.get('notify'))
             if success: return jsonify({'success': message}), 200
             return jsonify({'error': message}), 400
-        errors = form.password.errors
-        return jsonify({ 'error': errors}), 400
+        return send_errors_to_client(form=form)
 
     if id == current_user.id:
         flash('Cannot delete your own user account.', 'error')
@@ -199,8 +193,7 @@ def _update_user(id:str):
                 flash(message, 'success')
                 return jsonify({'success': message}), 200
             return jsonify({'error': message}), 400
-        errors = [*form.confirm_password.errors, *form.email.errors, *form.password.errors, *form.password_reenter.errors]
-        return jsonify({ 'error': errors}), 400
+        return send_errors_to_client(form=form)
     if not user:
         flash('User not found.', 'error')
         return redirect(url_for('admin._users'))
@@ -222,8 +215,7 @@ def _questions():
             )
             if success: return jsonify({'success': message}), 200
             return jsonify({'error': message}), 400
-        errors = form.data_file.errors
-        return jsonify({ 'error': errors}), 400
+        return send_errors_to_client(form=form)
 
     data = Dataset.query.all()
     return render_template('/admin/settings/questions.html', form=form, data=data)
@@ -299,9 +291,7 @@ def _create_test():
             flash(message=message, category='success')
             return jsonify({'success': message}), 200
         return jsonify({'error': message}), 400
-    else:
-        errors = [*form.start_date.errors, *form.expiry_date.errors, *form.time_limit.errors]
-        return jsonify({ 'error': errors}), 400
+    return send_errors_to_client(form=form)
 
 @admin.route('/tests/edit/', methods=['POST'])
 @login_required