Doc cleanup and test function for courses and course_relations models…

… added

backend/project/models/model_test.py

@@ -6,6 +6,7 @@
 import unittest
 import os
 from sqlalchemy import create_engine
+from sqlalchemy.exc import IntegrityError
 from sqlalchemy.orm import sessionmaker
 from project import db
 from project.models.courses import Courses
@@ -20,65 +21,134 @@ class TestModels(unittest.TestCase):
     """Test class for the database models"""
 
     def setUp(self):
-        # Create an in-memory SQLite database engine
-        # Load environment variables from .env file
+        """
+        Load the database uri and connect to it,
+        then create the tables defined by the models
+        and finally create a session so we can interact with the database
+        """
         load_dotenv()
-
-        # Access the environment variables
-        db_host = os.getenv('DB_HOST')
+        db_host = os.getenv("DB_HOST")
         engine = create_engine(db_host)
 
-        # Create tables defined by your models
+        # Create tables defined by your models,
+        # might want to change later since tables should already be defined in the database
         db.metadata.create_all(engine)
 
-        # Create a session for interacting with the database
         session = sessionmaker(bind=engine)
         self.session = session()
 
-
     def tearDown(self):
-        # Flush and close the session
+        """
+        Flush the whole test database and close the session
+        """
         self.session.expire_all()
         self.session.rollback()
         self.session.close()
-
-        # Delete all data from each table
+
         for table in reversed(db.metadata.sorted_tables):
             self.session.execute(table.delete())
-
-        # Commit the transaction
         self.session.commit()
 
     def test_users(self):
         """Test function for user model,
         first i simply test storing and retrieving a student,
-        then i test if a query for only the teachers/admin works"""
+        then i test if a query for only the teachers works"""
         user = Users(uid="student", is_teacher=False, is_admin=False)
-
-        # Add the user to the session
         self.session.add(user)
+        self.session.commit()  # only after commit the user will be in database
 
-        # Commit the session to persist the user in the database
-        self.session.commit()
-
-        # Query the database for the user based on their uid
         retrieved_user = self.session.query(Users).filter_by(uid="student").first()
 
-        # Assert that the retrieved user matches the one we created
         self.assertIsNotNone(retrieved_user)
         self.assertEqual(retrieved_user.uid, "student")
         self.assertEqual(retrieved_user.is_teacher, False)
         self.assertEqual(retrieved_user.is_admin, False)
 
         for i in range(10):
-            user = Users(uid=str(i),is_teacher=True,is_admin=False)
+            user = Users(uid=str(i), is_teacher=True, is_admin=False)
             self.session.add(user)
             self.session.commit()
         teacher_count = 0
         for usr in self.session.query(Users).filter_by(is_teacher=True):
-            teacher_count+=1
+            teacher_count += 1
             self.assertTrue(usr.is_teacher)
-        self.assertEqual(teacher_count,10)
+        self.assertEqual(teacher_count, 10)
+
+    def test_courses(self):
+        """
+        Test function for the courses model,
+        i will create some users, students and teachers and i will connect them to some courses
+        and then i will check if the queries work
+        """
+
+        sel2_teacher = Users(uid="teacher_sel2", is_teacher=True, is_admin=False)
+        sel2 = Courses(name="Sel2", teacher=sel2_teacher.uid)
+
+        with self.assertRaises(
+            IntegrityError,
+            msg="Courses should throw a foreign key error on the teacher uid",
+        ):
+            self.session.add(sel2)
+            self.session.commit()
+        self.session.rollback()
+
+        self.session.add(sel2_teacher)
+        self.session.commit()
+
+        self.session.add(sel2)
+        self.session.commit()
+        self.assertEqual(
+            self.session.query(Courses).filter_by(name="Sel2").first().teacher,
+            sel2_teacher.uid,
+        )
+
+        students = [
+            Users(uid="student_sel2_" + str(i), is_teacher=False, is_admin=False)
+            for i in range(5)
+        ]
+        self.session.add_all(students)
+        course_relations = [
+            CourseStudents(course_id=sel2.course_id, uid=students[i].uid)
+            for i in range(5)
+        ]
+
+        with self.assertRaises(
+            IntegrityError,
+            msg="Course_relations should throw a foreign key error on the student uid",
+        ):
+            self.session.add_all(course_relations)
+            self.session.commit()
+        self.session.rollback()
+
+        self.session.add_all(students)
+        self.session.commit()
+        self.session.add_all(course_relations)
+        self.session.commit()
+
+        student_check = [
+            s.uid
+            for s in self.session.query(CourseStudents)
+            .filter_by(course_id=sel2.course_id)
+            .all()
+        ]
+        student_uids = [s.uid for s in students]
+        self.assertListEqual(student_check, student_uids)
+
+        assistent = Users(uid="assistent_sel2")
+        self.session.add(assistent)
+        self.session.commit()
+
+        admin_relation = CourseAdmins(uid=assistent.uid, course_id=sel2.course_id)
+        self.session.add(admin_relation)
+        self.session.commit()
+
+        self.assertEqual(
+            self.session.query(CourseAdmins)
+            .filter_by(course_id=sel2.course_id)
+            .first()
+            .uid,
+            assistent.uid,
+        )
 
 
 if __name__ == "__main__":