def __init__(self, file_name):
"""
Repository for students using persistent storage powered by json text files.
:param file_name: string representing the location of the students.json
"""
StudentRepo.__init__(self)
self.file_name = file_name
file = open(self.file_name, "r")
for obj in json.load(file):
self.add_student(Student(obj["sid"], obj["name"]))
file.close()
def __init__(self, file_name):
"""
Repository for students using persistent storage powered by csv text files.
:param file_name: string representing the location of the students.csv
"""
StudentRepo.__init__(self)
self.file_name = file_name
file = open(self.file_name, "r")
for line in file.readlines():
line = line.strip(" \n")
stuff = line.split(",")
self.add_student(Student(int(stuff[0]), stuff[1]))
file.close()
def __init__(self,
student_repo=None,
discipline_repo=None,
grade_repo=None):
self._student_repo = student_repo
self._discipline_repo = discipline_repo
self._grade_repo = grade_repo
if student_repo is None:
self._student_repo = StudentRepo(self._generate_students())
if discipline_repo is None:
self._discipline_repo = DisciplineRepo(
self._generate_disciplines())
if grade_repo is None:
self._grade_repo = GradesRepo(self._generate_grades())
self._undo_service = UndoService(self._student_repo,
self._discipline_repo,
self._grade_repo)
def rem_student(self, student):
StudentRepo.rem_student(self, student)
self._save_file()
def upd_student(self, sid, name):
StudentRepo.upd_student(self, sid, name)
self._save_file()
def add_student(self, student):
StudentRepo.add_student(self, student)
self._save_file()
class Service:
def __init__(self,
student_repo=None,
discipline_repo=None,
grade_repo=None):
self._student_repo = student_repo
self._discipline_repo = discipline_repo
self._grade_repo = grade_repo
if student_repo is None:
self._student_repo = StudentRepo(self._generate_students())
if discipline_repo is None:
self._discipline_repo = DisciplineRepo(
self._generate_disciplines())
if grade_repo is None:
self._grade_repo = GradesRepo(self._generate_grades())
self._undo_service = UndoService(self._student_repo,
self._discipline_repo,
self._grade_repo)
@property
def students(self):
return self._student_repo.students
@property
def disciplines(self):
return self._discipline_repo.disciplines
@property
def grades(self):
return self._grade_repo.grades
@staticmethod
def _generate_students():
"""
Generates a list with 10 random students
:return: list with 10 objects of type Student
"""
names = Student.list_of_names()
students = []
for i in range(min(30, len(names))):
name = choice(names)
names.remove(name)
sid = randrange(1, 1000)
while sid in [x.sid for x in students]:
sid = randrange(1, 1000)
students.append(Student(sid, name))
return students
@staticmethod
def _generate_disciplines():
"""
Generates a list with 10 random disciplines
:return: list with 10 objects of type Discipline
"""
names = Discipline.list_of_names()
disciplines = []
for i in range(min(20, len(names))):
name = choice(names)
names.remove(name)
did = randrange(1, 1000)
while did in [x.did for x in disciplines]:
did = randrange(1, 1000)
disciplines.append(Discipline(did, name))
return disciplines
def _generate_grades(self):
"""
Generates a list with 10 random grades
:return: list with 10 objects of type Grade
"""
grades = []
for i in range(100):
sid = choice(self._student_repo.students).sid
did = choice(self._discipline_repo.disciplines).did
grade = randrange(0, 11)
grades.append(Grade(sid, did, grade))
return grades
def find_student(self, sid):
"""
Looks for a student with id=sid and returns one if it exists, None otherwise
:param sid: int
"""
return self._student_repo.find_student(sid)
def find_discipline(self, did):
"""
Looks for a discipline with id=did and returns one if it exists, None otherwise
:param did: int
"""
return self._discipline_repo.find_discipline(did)
def add_student(self, sid, name):
"""
Adds a student by calling the student repo
:param sid: int
:param name: string
:return: None
"""
student = Student(sid, name)
if self._student_repo.find_student(sid):
raise UniqueError("Student with id already exists")
self._undo_service.register_operation(
UndoObject(lambda: self._student_repo.rem_student(student),
lambda: self._student_repo.add_student(student)))
self._student_repo.add_student(student)
def add_discipline(self, did, name):
"""
Adds a discipline by calling the discipline repo
:param did: int
:param name: string
:return: None
"""
discipline = Discipline(did, name)
if self._discipline_repo.find_discipline(did):
raise UniqueError("Discipline with id already exists")
self._undo_service.register_operation(
UndoObject(
lambda: self._discipline_repo.rem_discipline(discipline),
lambda: self._discipline_repo.add_discipline(discipline)))
self._discipline_repo.add_discipline(discipline)
def rem_student(self, sid):
"""
Removes the student with id=sid from the student_repo
:param sid: integer
:return: None
"""
student = self._student_repo.find_student(sid)
if not student:
raise ExistenceError("No student with given id")
grades = list(filter(lambda x: x.sid == sid, self._grade_repo.grades))
def undo_function():
self._student_repo.add_student(student)
for grade in grades:
self._grade_repo.add_grade(grade)
def redo_function():
self._student_repo.rem_student(student)
for grade in grades:
self._grade_repo.rem_grade(grade)
self._undo_service.register_operation(
UndoObject(undo_function, redo_function))
self._student_repo.rem_student(student)
for y in [x for x in self._grade_repo.grades if x.sid == sid]:
self._grade_repo.rem_grade(y)
def rem_discipline(self, did):
"""
Removes the discipline with id=did from the discipline repo
:param did:
:return: None
"""
discipline = self._discipline_repo.find_discipline(did)
if not discipline:
raise ExistenceError("No discipline with given id")
grades = list(filter(lambda x: x.did == did, self._grade_repo.grades))
def undo_function():
self._discipline_repo.add_discipline(discipline)
for grade in grades:
self._grade_repo.add_grade(grade)
def redo_function():
self._discipline_repo.rem_discipline(discipline)
for grade in grades:
self._grade_repo.rem_grade(grade)
self._undo_service.register_operation(
UndoObject(undo_function, redo_function))
self._discipline_repo.rem_discipline(discipline)
for y in [x for x in self._grade_repo.grades if x.did == did]:
self._grade_repo.rem_grade(y)
def upd_student(self, sid, name):
"""
Sets the name of student from student_repo with id=sid to name
:param sid: integer
:param name: string
:return: None
"""
student = self._student_repo.find_student(sid)
if not student:
raise ExistenceError("No student with given id")
old_name = student.name
self._undo_service.register_operation(
UndoObject(lambda: self._student_repo.upd_student(sid, old_name),
lambda: self._student_repo.upd_student(sid, name)))
self._student_repo.upd_student(sid, name)
def upd_discipline(self, did, name):
"""
Sets the name of discipline from discipline_repo with id=did to name
:param did: integer
:param name: string
:return: None
"""
discipline = self._discipline_repo.find_discipline(did)
if not discipline:
raise ExistenceError("No discipline with given id")
old_name = discipline.name
self._undo_service.register_operation(
UndoObject(
lambda: self._discipline_repo.upd_discipline(did, old_name),
lambda: self._discipline_repo.upd_discipline(did, name)))
self._discipline_repo.upd_discipline(did, name)
def grade_student(self, sid, did, grade_value):
"""
Adds a grade to the list from grade_repo
:param sid: int
:param did: int
:param grade_value: int
:return: None
"""
grade = Grade(sid, did, grade_value)
if not self._student_repo.find_student(grade.sid):
raise ExistenceError("No student with given id")
if not self._discipline_repo.find_discipline(grade.did):
raise ExistenceError("No discipline with given id")
self._undo_service.register_operation(
UndoObject(lambda: self._grade_repo.rem_grade(grade),
lambda: self._grade_repo.add_grade(grade)))
self._grade_repo.add_grade(grade)
def lookup_student(self, name):
"""
Returns a list of all students who match the name with the parameter name, case insensitive
:param name: string
:return: list
"""
return [
student for student in self._student_repo.students
if re.search(name, student.name, re.IGNORECASE)
]
def lookup_discipline(self, name):
"""
Returns a list of all disciplines who match the name with the parameter name, case insensitive
:param name: string
:return: list
"""
return [
discipline for discipline in self._discipline_repo.disciplines
if re.search(name, discipline.name, re.IGNORECASE)
]
def list_grades_to_string(self):
"""
:return: list of user readable strings made from each grade in the list of grades
"""
s = []
for i in self._grade_repo.grades:
s.append(
"Student {0} with id={1} has grade {2} at discipline {3} with id={4}"
.format([
x.name for x in self._student_repo.students
if x.sid == i.sid
][0], i.sid, i.grade, [
x.name for x in self._discipline_repo.disciplines
if x.did == i.did
][0], i.did))
return s
def _grouping_students(self):
"""
Returns a dictionary with key as student.sid and value as another dictionary with key as discipline.did and
value as the average grade at that discipline for that student
:return: dict
"""
d_cnt = {}
d_sum = {}
for g in self._grade_repo.grades:
if g.sid not in d_cnt:
d_cnt[g.sid] = {}
if g.did not in d_cnt[g.sid]:
d_cnt[g.sid][g.did] = 0
if g.sid not in d_sum:
d_sum[g.sid] = {}
if g.did not in d_sum[g.sid]:
d_sum[g.sid][g.did] = 0
d_cnt[g.sid][g.did] += 1
d_sum[g.sid][g.did] += g.grade
for key in d_sum:
for key2 in d_sum[key]:
d_sum[key][key2] /= d_cnt[key][key2]
return d_sum
def students_failing(self):
"""
Returns a list of triples(triples are lists with 3 elements), first element is student.sid, second element is
discipline.did and third element is the grade of that student at that discipline. Returns only the triples with
grade < 5(the failing grade)
:return: list
"""
d = self._grouping_students()
v = []
for key in d:
for key2 in d[key]:
if d[key][key2] < 5:
v.append([key, key2, d[key][key2]])
return v
def students_failing_to_string(self):
"""
:return: list of user readable strings for each failing student
"""
s = []
for x in self.students_failing():
s.append("Student {0} is failing at {1} with grade {2}".format(
self.find_student(x[0]).name,
self.find_discipline(x[1]).name, x[2]))
return s
def rank_students(self):
"""
returns a list of pairs(pairs are lists of 2 elements), first element is student.sid, second element is
weighted average grade of that student across all disciplines sorted in descending order of grade
:return: list
"""
d = self._grouping_students()
v = []
for key in d:
v.append([key, 0])
for key2 in d[key]:
v[-1][1] += d[key][key2]
v[-1][1] /= len(d[key])
return sort(v, key=lambda x: x[1], reverse=True)
def rank_students_to_string(self):
"""
:return: list of user readable strings for the ranking of students
"""
s = []
for x in self.rank_students():
s.append("Student {0} has an aggregated average of {1}".format(
self.find_student(x[0]).name, x[1]))
return s
def rank_disciplines(self):
"""
returns a list of pairs(pairs are lists of 2 elements), first element is discipline.sid, second element is
average grade of that discipline across all grades sorted in descending order of grade
:return: list
"""
d = self._grouping_students()
d2_sum = {}
d2_cnt = {}
for sid in d:
for did in d[sid]:
if did not in d2_sum:
d2_sum[did] = 0
d2_sum[did] += d[sid][did]
if did not in d2_cnt:
d2_cnt[did] = 0
d2_cnt[did] += 1
for did in d2_sum:
d2_sum[did] /= d2_cnt[did]
v = []
for key, value in d2_sum.items():
v.append([key, value])
return sort(v, key=lambda x: x[1], reverse=True)
def rank_disciplines_to_string(self):
"""
:return: list of user readable strings for the ranking of disciplines
"""
s = []
for x in self.rank_disciplines():
s.append(
"Discipline {0} has average grade of {1} across all students".
format(self.find_discipline(x[0]).name, x[1]))
return s
def undo(self):
"""
undo function from service
"""
self._undo_service.undo()
def redo(self):
"""
redo function from service
"""
self._undo_service.redo()