feat: Add exercises tags

lms/lmsdb/models.py

@@ -346,6 +346,27 @@ def on_notification_saved(
         instance.delete_instance()
 
 
+class Tag(BaseModel):
+    text = TextField()
+    course = ForeignKeyField(Course)
+    date_created = DateTimeField(default=datetime.now)
+
+    class Meta:
+        indexes = (
+            (('text', 'course_id'), True),
+        )
+
+    @classmethod
+    def create_tag(cls, text: str, course: Course) -> 'Tag':
+        instance, _ = cls.get_or_create(
+            **{cls.text.name: html.escape(text), cls.course.name: course},
+        )
+        return instance
+
+    def __str__(self):
+        return self.text
+
+
 class Exercise(BaseModel):
     subject = CharField()
     date = DateTimeField()
@@ -376,12 +397,8 @@ def is_number_exists(cls, number: int) -> bool:
         return cls.select().where(cls.number == number).exists()
 
     @classmethod
-    def get_objects(
-        cls, user_id: int, fetch_archived: bool = False,
-        from_all_courses: bool = False,
-    ):
-        user = User.get(User.id == user_id)
-        exercises = (
+    def by_user(cls, user_id: int):
+        return (
             cls
             .select()
             .join(Course)
@@ -390,10 +407,20 @@ def get_objects(
             .switch()
             .order_by(UserCourse.date, Exercise.number, Exercise.order)
         )
+
+    @classmethod
+    def get_objects(
+        cls, user_id: int, fetch_archived: bool = False,
+        from_all_courses: bool = False, exercise_tag: Optional[str] = None,
+    ):
+        user = User.get(User.id == user_id)
+        exercises = cls.by_user(user_id)
         if not from_all_courses:
             exercises = exercises.where(
                 UserCourse.course == user.last_course_viewed,
             )
+        if exercise_tag:
+            exercises = Exercise.by_tags(exercises, exercise_tag)
         if not fetch_archived:
             exercises = exercises.where(cls.is_archived == False)  # NOQA: E712
         return exercises
@@ -408,12 +435,22 @@ def as_dict(self) -> Dict[str, Any]:
             'exercise_number': self.number,
             'course_id': self.course.id,
             'course_name': self.course.name,
+            'tags': ExerciseTag.by_exercise(self),
         }
 
     @staticmethod
     def as_dicts(exercises: Iterable['Exercise']) -> ExercisesDictById:
         return {exercise.id: exercise.as_dict() for exercise in exercises}
 
+    @staticmethod
+    def by_tags(exercises: Iterable['Exercise'], exercise_tag: str):
+        return (
+            exercises
+            .join(ExerciseTag)
+            .join(Tag)
+            .where(Tag.text == exercise_tag)
+        )
+
     def __str__(self):
         return self.subject
 
@@ -426,6 +463,23 @@ def exercise_number_save_handler(model_class, instance, created):
         instance.number = model_class.get_highest_number() + 1
 
 
+class ExerciseTag(BaseModel):
+    exercise = ForeignKeyField(Exercise)
+    tag = ForeignKeyField(Tag)
+    date = DateTimeField(default=datetime.now)
+
+    @classmethod
+    def by_exercise(
+        cls, exercise: Exercise,
+    ) -> Union[Iterable['ExerciseTag'], 'ExerciseTag']:
+        return (
+            cls
+            .select()
+            .where(cls.exercise == exercise)
+            .order_by(cls.date)
+        )
+
+
 class SolutionState(enum.Enum):
     CREATED = 'Created'
     IN_CHECKING = 'In checking'
@@ -561,11 +615,11 @@ def test_results(self) -> Iterable[dict]:
     @classmethod
     def of_user(
         cls, user_id: int, with_archived: bool = False,
-        from_all_courses: bool = False,
+        from_all_courses: bool = False, exercise_tag: Optional[str] = None,
     ) -> Iterable[Dict[str, Any]]:
         db_exercises = Exercise.get_objects(
             user_id=user_id, fetch_archived=with_archived,
-            from_all_courses=from_all_courses,
+            from_all_courses=from_all_courses, exercise_tag=exercise_tag,
         )
         exercises = Exercise.as_dicts(db_exercises)
         solutions = (

lms/lmsweb/views.py

@@ -356,6 +356,29 @@ def exercises_page():
     )
 
 
+@webapp.route('/exercises/<tag_name>')
+@login_required
+def exercises_tag_page(tag_name: str):
+    fetch_archived = bool(request.args.get('archived'))
+    try:
+        solutions.check_tag_name(tag_name, current_user.last_course_viewed)
+    except LmsError as e:
+        error_message, status_code = e.args
+        return fail(status_code, error_message)
+
+    exercises = Solution.of_user(
+        current_user.id, fetch_archived, exercise_tag=tag_name,
+    )
+    is_manager = current_user.role.is_manager
+    return render_template(
+        'exercises.html',
+        exercises=exercises,
+        is_manager=is_manager,
+        fetch_archived=fetch_archived,
+        tag_name=tag_name,
+    )
+
+
 @webapp.route('/notifications')
 @login_required
 def get_notifications():
@@ -479,7 +502,7 @@ def comment():
 
 @webapp.route('/send/<int:course_id>/<int:_exercise_number>')
 @login_required
-def send(course_id: int, _exercise_number: Optional[int]):
+def send(course_id: int, _exercise_number: Optional[int] = None):
     if not UserCourse.is_user_registered(current_user.id, course_id):
         return fail(403, "You aren't allowed to watch this page.")
     return render_template('upload.html', course_id=course_id)

lms/models/solutions.py

@@ -8,11 +8,13 @@
 from playhouse.shortcuts import model_to_dict  # type: ignore
 
 from lms.extractors.base import File
-from lms.lmsdb.models import SharedSolution, Solution, SolutionFile, User
+from lms.lmsdb.models import (
+    Course, SharedSolution, Solution, SolutionFile, User,
+)
 from lms.lmstests.public.general import tasks as general_tasks
 from lms.lmstests.public.identical_tests import tasks as identical_tests_tasks
 from lms.lmsweb import config, routes
-from lms.models import comments, notifications
+from lms.models import comments, notifications, tags
 from lms.models.errors import ForbiddenPermission, ResourceNotFound
 from lms.utils.files import ALLOWED_IMAGES_EXTENSIONS
 
@@ -205,3 +207,11 @@ def get_files_tree(files: Iterable[SolutionFile]) -> List[Dict[str, Any]]:
     for file in file_details:
         del file['fullpath']
     return file_details
+
+
+def check_tag_name(tag_name: str, course: Course) -> None:
+    if not tags.get_exercises_of(course, tag_name):
+        raise ResourceNotFound(
+            f'No such tag {tag_name} for course '
+            f'{current_user.last_course_viewed.name}.', 404,
+        )

lms/models/tags.py

@@ -0,0 +1,33 @@
+from typing import Iterable, Optional, Union
+
+from lms.lmsdb.models import Course, Exercise, ExerciseTag, Tag
+
+
+def get_exercises_of(
+    course: Course, tag_name: str,
+) -> Union[Iterable['ExerciseTag'], 'ExerciseTag']:
+    return (
+        ExerciseTag
+        .select(ExerciseTag.exercise)
+        .join(Tag)
+        .where(Tag.text == tag_name, Tag.course == course)
+    )
+
+
+def of_exercise(
+    exercise_id: Optional[int] = None, course: Optional[int] = None,
+    number: Optional[int] = None,
+) -> Optional[Union[Iterable['ExerciseTag'], 'ExerciseTag']]:
+    if exercise_id is not None:
+        return ExerciseTag.select().where(ExerciseTag.exercise == id)
+    elif course is not None:
+        tags = (
+            ExerciseTag
+            .select()
+            .join(Exercise)
+            .where(Exercise.course == course)
+        )
+        if number is not None:
+            tags = tags.where(Exercise.number == number)
+        return tags
+    return None

lms/static/my.css

@@ -177,6 +177,16 @@ a {
   line-height: 3rem;
 }
 
+.exercise-tags {
+  align-items: center;
+  display: flex;
+  font-size: 1em;
+  height: 3rem;
+  justify-content: center;
+  text-align: center;
+  white-space: normal;
+}
+
 .exercise-send {
   display: flex;
   flex-direction: row;

lms/templates/exercises.html

@@ -5,7 +5,7 @@
   <div id="exercises-page" class="page {{ direction }}">
     <div id="exercises-header">
       <div id="main-title">
-        <h1 id="exercises-head">{{ _('Exercises') }}</h1>
+        <h1 id="exercises-head">{{ _('Exercises') }}{% if tag_name %} - #{{ tag_name | e }}{% endif %}</h1>
       </div>
     </div>
     <div id="exercises">
@@ -14,6 +14,11 @@ <h1 id="exercises-head">{{ _('Exercises') }}</h1>
         <div class="right-side {{ direction }}-language">
           <div class="exercise-number me-3">{{ exercise['exercise_number'] }}</div>
           <div class="exercise-name"><div class="ex-title">{{ exercise['exercise_name'] | e }}</div></div>
+          <div class="exercise-tags ms-1">
+            {% for tag in exercise.tags %}
+              <a class="ms-1" id="exercise-tag-link" href="{{ url_for('exercises_tag_page', tag_name=tag.tag) }}">#{{ tag.tag | e }}</a>
+            {% endfor %}
+          </div>
         </div>
         <div class="left-side">
           <div class="comments-count">

lms/templates/navbar.html

@@ -66,7 +66,7 @@
             </a>
           </li>
         {% endif -%}
-        {%- if not exercises or fetch_archived %}
+        {%- if not exercises or fetch_archived or tag_name %}
         <li class="nav-item">
           <a href="/exercises" class="nav-link">
             <i class="fa fa-book" aria-hidden="true"></i>

tests/conftest.py

@@ -15,8 +15,9 @@
 import pytest
 
 from lms.lmsdb.models import (
-    ALL_MODELS, Comment, CommentText, Course, Exercise, Note, Notification,
-    Role, RoleOptions, SharedSolution, Solution, User, UserCourse,
+    ALL_MODELS, Comment, CommentText, Course, Exercise, ExerciseTag,
+    Tag, Note, Notification, Role, RoleOptions, SharedSolution,
+    Solution, User, UserCourse,
 )
 from lms.extractors.base import File
 from lms.lmstests.public import celery_app as public_app
@@ -308,14 +309,19 @@ def create_exercise(
     )
 
 
+def create_exercise_tag(tag_text: str, course: Course, exercise: Exercise):
+    new_tag_id = Tag.create_tag(text=tag_text, course=course).id
+    return ExerciseTag.create(exercise=exercise, tag=new_tag_id)
+
+
 def create_shared_solution(solution: Solution) -> SharedSolution:
     return SharedSolution.create_new(solution=solution)
 
 
 def create_note(
     creator: User,
     user: User,
-    note_text: CommentText,
+    note_text: str,
     privacy: int,
 ):
     new_note_id = CommentText.create_comment(text=note_text).id

tests/test_exercises.py

@@ -1,6 +1,7 @@
 import datetime
 
 from lms.lmsdb.models import Course, Exercise, User
+from lms.models import tags
 from tests import conftest
 
 
@@ -52,3 +53,38 @@ def test_courses_exercises(
         template, _ = captured_templates[-1]
         assert template.name == 'exercises.html'
         assert len(list(Exercise.get_objects(student_user.id))) == 2
+
+    @staticmethod
+    def test_exercise_tags(
+        student_user: User, course: Course, exercise: Exercise,
+    ):
+        client = conftest.get_logged_user(username=student_user.username)
+        conftest.create_usercourse(student_user, course)
+        client.get(f'course/{course.id}')
+        conftest.create_exercise_tag('tag1', course, exercise)
+        tag_response = client.get('/exercises/tag1')
+        assert tag_response.status_code == 200
+
+        course2 = conftest.create_course(index=1)
+        exercise2 = conftest.create_exercise(course2, 2)
+        conftest.create_usercourse(student_user, course2)
+        conftest.create_exercise_tag('tag2', course2, exercise2)
+        bad_tag_response = client.get('/exercises/tag2')
+        assert bad_tag_response.status_code == 404
+
+        client.get(f'course/{course2.id}')
+        success_tag_response = client.get('/exercises/tag2')
+        assert success_tag_response.status_code == 200
+
+        another_bad_tag_response = client.get('/exercises/wrongtag')
+        assert another_bad_tag_response.status_code == 404
+
+    @staticmethod
+    def test_course_tags(course: Course, exercise: Exercise):
+        course2 = conftest.create_course(index=1)
+        conftest.create_exercise_tag('tag1', course, exercise)
+        conftest.create_exercise_tag('tag2', course, exercise)
+        exercise2 = conftest.create_exercise(course, 2)
+        conftest.create_exercise_tag('tag1', course, exercise2)
+        assert len(tags.of_exercise(course=course.id)) == 3
+        assert len(tags.of_exercise(course=course2.id)) == 0