feat: Join public courses

lms/lmsdb/bootstrap.py

@@ -278,21 +278,34 @@ def _add_exercise_course_id_and_number_columns_constraint() -> bool:
     Exercise = models.Exercise
     migrator = db_config.get_migrator_instance()
     with db_config.database.transaction():
-        course_not_exists = _add_not_null_column(Exercise, Exercise.course)
-        number_not_exists = _add_not_null_column(Exercise, Exercise.number)
-        if course_not_exists and number_not_exists:
+        _add_not_null_column(Exercise, Exercise.course)
+        _add_not_null_column(Exercise, Exercise.number)
+        try:
             migrate(
                 migrator.add_index('exercise', ('course_id', 'number'), True),
             )
+        except OperationalError as e:
+            if 'already exists' in str(e):
+                log.info(f'index exercise already exists: {e}')
+            else:
+                raise
         db_config.database.commit()
 
 
 def _add_user_course_constaint() -> bool:
     migrator = db_config.get_migrator_instance()
     with db_config.database.transaction():
-        migrate(
-            migrator.add_index('usercourse', ('user_id', 'course_id'), True),
-        )
+        try:
+            migrate(
+                migrator.add_index(
+                    'usercourse', ('user_id', 'course_id'), True,
+                ),
+            )
+        except OperationalError as e:
+            if 'already exists' in str(e):
+                log.info(f'index usercourse already exists: {e}')
+            else:
+                raise
         db_config.database.commit()
 
 

lms/lmsdb/models.py

@@ -159,6 +159,14 @@ def fetch(cls, user: 'User') -> Iterable['Course']:
             .order_by(Course.name.desc())
         )
 
+    @classmethod
+    def public_courses(cls):
+        return cls.select().where(cls.is_public)
+
+    @classmethod
+    def public_course_exists(cls):
+        return cls.public_courses().exists()
+
     def __str__(self):
         return f'{self.name}: {self.date} - {self.end_date}'
 
@@ -279,7 +287,7 @@ def is_user_registered(cls, user_id: int, course_id: int) -> bool:
 @post_save(sender=UserCourse)
 def on_save_user_course(model_class, instance, created):
     """Changes user's last course viewed."""
-    if instance.user.last_course_viewed is None:
+    if instance.user.last_course_viewed is None or instance.course.is_public:
         instance.user.last_course_viewed = instance.course
         instance.user.save()
 

lms/lmsweb/translations/he/LC_MESSAGES/messages.po

@@ -7,7 +7,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version:  1.0\n"
 "Report-Msgid-Bugs-To: EMAIL@ADDRESS\n"
-"POT-Creation-Date: 2021-10-03 22:01+0300\n"
+"POT-Creation-Date: 2021-10-06 15:07+0300\n"
 "PO-Revision-Date: 2021-09-29 11:30+0300\n"
 "Last-Translator: Or Ronai\n"
 "Language: he\n"
@@ -18,7 +18,7 @@ msgstr ""
 "Content-Transfer-Encoding: 8bit\n"
 "Generated-By: Babel 2.9.1\n"
 
-#: lmsdb/models.py:879
+#: lmsdb/models.py:864
 msgid "Fatal error"
 msgstr "כישלון חמור"
 
@@ -116,14 +116,19 @@ msgstr "%(checker)s הגיב לך על תרגיל \"%(subject)s\"."
 msgid "Your solution for the \"%(subject)s\" exercise has been checked."
 msgstr "הפתרון שלך לתרגיל \"%(subject)s\" נבדק."
 
-#: models/users.py:28
+#: models/users.py:29
 msgid "Invalid username or password"
 msgstr "שם המשתמש או הסיסמה שהוזנו לא תקינים"
 
-#: models/users.py:31
+#: models/users.py:32
 msgid "You have to confirm your registration with the link sent to your email"
 msgstr "עליך לאשר את מייל האימות"
 
+#: models/users.py:50
+#, python-format
+msgid "You are already registered to %(course_name)s course."
+msgstr "אתה כבר רשום לקורס %(course_name)s."
+
 #: templates/banned.html:8 templates/login.html:7
 #: templates/recover-password.html:8 templates/reset-password.html:8
 #: templates/signup.html:8
@@ -247,6 +252,11 @@ msgstr "בדוק תרגילים"
 msgid "Logout"
 msgstr "התנתקות"
 
+#: templates/public-courses.html:6
+#, fuzzy
+msgid "Public Courses List"
+msgstr "רשימת קורסים פתוחים"
+
 #: templates/recover-password.html:9 templates/recover-password.html:17
 #: templates/reset-password.html:9
 msgid "Reset Password"
@@ -293,7 +303,7 @@ msgstr "חמ\"ל תרגילים"
 msgid "Name"
 msgstr "שם"
 
-#: templates/status.html:13 templates/user.html:44
+#: templates/status.html:13 templates/user.html:46
 msgid "Checked"
 msgstr "נבדק/ו"
 
@@ -341,27 +351,31 @@ msgstr "פרטי משתמש"
 msgid "Actions"
 msgstr "פעולות"
 
-#: templates/user.html:24
+#: templates/user.html:21
+msgid "Join Courses"
+msgstr "הירשם לקורסים"
+
+#: templates/user.html:27
 msgid "Exercises Submitted"
 msgstr "תרגילים שהוגשו"
 
 #: templates/user.html:29
 msgid "Course name"
 msgstr "שם קורס"
 
-#: templates/user.html:30
+#: templates/user.html:33
 msgid "Exercise name"
 msgstr "שם תרגיל"
 
-#: templates/user.html:31
+#: templates/user.html:34
 msgid "Submission status"
 msgstr "מצב הגשה"
 
-#: templates/user.html:32
+#: templates/user.html:35
 msgid "Submission"
 msgstr "הגשה"
 
-#: templates/user.html:33
+#: templates/user.html:36
 msgid "Checker"
 msgstr "בודק"
 

lms/lmsweb/views.py

@@ -35,10 +35,10 @@
     PERMISSIVE_CORS, get_next_url, login_manager,
 )
 from lms.models import (
-    comments, notes, notifications, share_link, solutions, upload,
+    comments, notes, notifications, share_link, solutions, upload, users,
 )
 from lms.models.errors import (
-    FileSizeError, ForbiddenPermission, LmsError,
+    AlreadyExists, FileSizeError, ForbiddenPermission, LmsError,
     UnauthorizedError, UploadError, fail,
 )
 from lms.models.users import SERIALIZER, auth, retrieve_salt
@@ -505,9 +505,37 @@ def user(user_id):
         user=target_user,
         is_manager=is_manager,
         notes_options=Note.get_note_options(),
+        public_course_exists=Course.public_course_exists(),
     )
 
 
+@webapp.route('/course')
+@login_required
+def public_courses():
+    return render_template(
+        'public-courses.html',
+        courses=Course.public_courses(),
+    )
+
+
+@webapp.route('/course/join/<int:course_id>')
+@login_required
+def join_public_course(course_id: int):
+    course = Course.get_or_none(course_id)
+    if course is None:
+        return fail(404, 'There is no such course.')
+    if not course.is_public:
+        return fail(403, "You aren't allowed to do this method.")
+
+    try:
+        users.join_public_course(course, current_user)
+    except AlreadyExists as e:
+        error_message, status_code = e.args
+        return fail(status_code, error_message)
+
+    return redirect(url_for('exercises_page'))
+
+
 @webapp.route('/send/<int:course_id>', methods=['GET'])
 @login_required
 def send_(course_id: int):

lms/models/errors.py

@@ -5,7 +5,7 @@ class LmsError(Exception):
     pass
 
 
-class AlreadyExists(LmsError):
+class AlreadyExists(LmsError):  # Usually a 409 HTTP Error
     pass
 
 

lms/models/users.py

@@ -3,10 +3,11 @@
 from flask_babel import gettext as _  # type: ignore
 from itsdangerous import URLSafeTimedSerializer
 
-from lms.lmsdb.models import User
+from lms.lmsdb.models import Course, User, UserCourse
 from lms.lmsweb import config
 from lms.models.errors import (
-    ForbiddenPermission, UnauthorizedError, UnhashedPasswordError,
+    AlreadyExists, ForbiddenPermission, UnauthorizedError,
+    UnhashedPasswordError,
 )
 
 
@@ -38,3 +39,16 @@ def auth(username: str, password: str) -> User:
 
 def generate_user_token(user: User) -> str:
     return SERIALIZER.dumps(user.mail_address, salt=retrieve_salt(user))
+
+
+def join_public_course(course: Course, user: User) -> None:
+    __, created = UserCourse.get_or_create(**{
+        UserCourse.user.name: user, UserCourse.course.name: course,
+    })
+    if not created:
+        raise AlreadyExists(
+            _(
+                'You are already registered to %(course_name)s course.',
+                course_name=course.name,
+            ), 409,
+        )

lms/static/my.css

@@ -835,16 +835,18 @@ code .grader-add .fa {
 }
 
 /* User's page */
-#user {
+#user, #public-courses {
   text-align: right;
 }
 
-#user h1 {
+#user h1,
+#public-courses h1 {
   margin: 5vh 0;
   text-align: center;
 }
 
-#user .body {
+#user .body,
+#public-courses .body {
   width: 80vw;
   margin: auto;
 }
@@ -853,7 +855,8 @@ code .grader-add .fa {
   width: 80vw;
 }
 
-#user .user-actions {
+#user .user-actions,
+#public-courses .public-courses-links {
   margin-bottom: 5em;
 }
 

lms/templates/public-courses.html

@@ -0,0 +1,19 @@
+{% extends 'base.html' %}
+
+{% block page_content %}
+<div id="page-public-courses">
+  <div id="public-courses" class="{{ direction }}">
+    <h1>{{ _('Public Courses List') }}</h1>
+    <div class="body">
+      <div class="public-courses-links {{ direction }}">
+        <ul>
+          {% for course in courses %}
+            <li><a href="{{ url_for('join_public_course', course_id=course.id) }}" role="button">{{ course.name | e }}</a></li>
+          {% endfor %}
+        </ul>
+      </div>
+    </div>
+  </div>
+</div>
+
+{% endblock %}

lms/templates/user.html

@@ -17,6 +17,9 @@ <h2>{{ _('Actions') }}:</h2>
         <div id="change-password-user">
           <ul>
             <li><a href="{{ url_for('change_password') }}" role="button">{{ _('Change Password') }}</a></li>
+            {% if public_course_exists %}
+            <li><a href="{{ url_for('public_courses') }}" role="button">{{ _('Join Courses') }}</a></li>
+            {% endif %}
           </ul>
         </div>
       </div>

tests/test_registration.py

@@ -4,7 +4,7 @@
 from flask.testing import FlaskClient
 
 from lms.lmsweb.config import CONFIRMATION_TIME
-from lms.lmsdb.models import User
+from lms.lmsdb.models import Course, User
 from lms.models.users import generate_user_token
 from tests import conftest
 
@@ -146,3 +146,24 @@ def test_registartion_closed(client: FlaskClient, captured_templates):
         template, _ = captured_templates[-1]
         assert template.name == 'login.html'
         assert '/signup' not in response.get_data(as_text=True)
+
+    @staticmethod
+    def test_register_public_course(
+        student_user: User, course: Course, captured_templates,
+    ):
+        client = conftest.get_logged_user(username=student_user.username)
+        not_public_course_response = client.get(f'/course/join/{course.id}')
+        assert not_public_course_response.status_code == 403
+
+        unknown_course_response = client.get('/course/join/123456')
+        assert unknown_course_response.status_code == 404
+
+        course.is_public = True
+        course.save()
+        course = Course.get_by_id(course.id)
+        client.get(f'/course/join/{course.id}')
+        template, _ = captured_templates[-1]
+        assert template.name == 'exercises.html'
+
+        already_registered_response = client.get(f'/course/join/{course.id}')
+        assert already_registered_response.status_code == 409