def deleteDept(self, request):
''' delete department given department ID. delete in the order Schedule, Student and Course first'''
# Enhancement. Deleting entity using other details like department name
try:
# Creating the key for given department id
d_key = ndb.Key(Department, int(request.id))
# Fetching and deleting the entity
dept = Department.get_by_id(request.id)
''' Dependencies'''
# check if department exists in Student kind
st_query = Student.query(Student.department == d_key)
co_query = Course.query(Course.department == d_key)
sch_query = Schedule.query(Schedule.department == d_key)
if sch_query.get():
# entity found in Schedule. Invoke Dependency error
response = STORED_RESPONSES.items[DEP_ERR_DEPT_SCH_ID]
elif st_query.get():
# entity found in Student. Invoke Dependency error
response = STORED_RESPONSES.items[DEP_ERR_DEPT_ST_ID]
elif co_query.get():
# entity found in Course. Invoke Dependency error
response = STORED_RESPONSES.items[DEP_ERR_DEPT_CO_ID]
else:
# no dependencies found. delete department
print("Department to be deleted = ", dept)
d_key.delete()
response = STORED_RESPONSES.items[DELETE_ID]
return response
except:
raise endpoints.EndpointsErrorMessage(
"Unable to delete entity. Please try again later!")
def deleteDept(self, dept_id):
''' delete department given department ID. delete in the order Schedule, Student and Course first'''
# Enhancement. Deleting entity using other details like department name
try:
# Creating the key for given department id
d_key = ndb.Key(Department, int(dept_id))
# Fetching and deleting the entity
dept = Department.get_by_id(dept_id)
''' Dependencies'''
# check if department exists in Student kind
st_query = Student.query(Student.department == d_key)
co_query = Course.query(Course.department == d_key)
sch_query = Schedule.query(Schedule.department == d_key)
if sch_query.get():
# entity found in Schedule. Invoke Dependency error
response = R_DEP_ERR_DELCHILD.format("Schedule", "Department")
elif st_query.get():
# entity found in Student. Invoke Dependency error
response = R_DEP_ERR_DELCHILD.format("Student", "Department")
elif co_query.get():
# entity found in Course. Invoke Dependency error
response = R_DEP_ERR_DELCHILD.format("Course", "Department")
else:
# no dependencies found. delete department
d_key.delete()
response = R_SUCC_DEL.format("Department", str(d_key))
except Exception, e:
response = R_SERV_ERR.format(str(e))
def view_dept_courses(self, request):
''' Allows user to list courses a department provides in a specific quarter'''
d_key = ndb.Key(Department, request.department_id)
query = Schedule.query(Schedule.department == d_key,
Schedule.quarter == request.quarter,
Schedule.year == request.year)
print("view_dept_courses method: converting query to messages")
return self.queryToCoursesMessage(query)
def insertSchedule(self, request):
''' insert a course schedule for given quarter. Require course ID, quarter and year.'''
response = ""
# read all inputs
course_id = request.get('course_id')
year = request.get('year')
quarter = request.get('quarter')
# check if required fields are not blank
if (course_id and year and quarter):
# validate inputs
if (is_int(course_id) and is_int(year) and is_int(quarter)):
course_id = int(course_id)
year = int(year)
quarter = int(quarter)
# validate inputs continued
# Get current year
# Year needs to be prev, curr and next year
if (self.validate_year(year)
and self.validate_quarter(quarter)):
# Validate course id
c_key = ndb.Key(Course, course_id)
# Check if entity exists
if c_key.get():
# fetch the respective dept for that course id
d_key = c_key.get().department
# check for duplicate entries
query = Schedule.query(Schedule.course == c_key,
Schedule.quarter == quarter,
Schedule.year == year)
if (not query.get()):
# insert schedule
response = self.upsertSchedule(year=year,
quarter=quarter,
d_key=d_key,
course_id=course_id)
else:
response = R_DUP_ID_ERR.format("Schedule")
else:
response = R_DEP_ERR_INVCOUR
else:
response = R_PROP_VAL_ERR.format(
"Year and Quarter",
"integers of values (previous year, current year and next year) and range(1-4) respectively"
)
else:
response = R_ID_VAL_ERR.format(
"Course ID and Year and Quarter")
else:
response = R_REQ_FIELD_ERR.format("Course ID and Year and Quarter")
return response
def deleteSchedule(self, request):
''' delete a schedule given course ID quarter and year'''
try:
# Get Course id
c_key = ndb.Key(Course, int(request.course_id))
print("deleteSchedule Method: Going to query object")
# Get schedule id from given year, quarter and course
query = Schedule.query(Schedule.course == c_key,
Schedule.quarter == request.quarter,
Schedule.year == request.year)
print("deleteSchedule method: After query = ", query)
schedule = query.get()
if schedule:
print("deleteSchedule method: schedule -", schedule.key,
" exists for course key = ", c_key)
# delete all enrollments for that schedule
query = Enrollment.query(
Enrollment.schedule ==
schedule.key) #ndb.Key(Schedule, schedule.id))
for enrollment in query.fetch():
print("deleteSchedule Method: Fetching query = ",
enrollment)
# delete course from Student model
student = enrollment.student.get()
print("===========Student list for course========",
student)
if (c_key in student.study_lists):
student.study_lists.remove(c_key)
# update student entity
student.put()
print(
"deleteSchedule method: course not in student list"
)
print(
"deleteSchedule method: Going to delete enrollment with Key = ",
enrollment.key)
# delete enrollment
#enrollment = q.get()
#ndb.Key(Enrollment, enrollment.id).delete()
enrollment.key.delete()
print(
"deleteSchedule method: deleted enrollment successfully"
)
#ndb.Key(Enrollment, q.id).delete()
# delete schedule
schedule.key.delete()
except:
raise endpoints.EndpointsErrorMessage(
'Error while deleting a schedule.')
return STORED_RESPONSES.items[DELETE_ID]
def view_students_in_course(self, request):
''' List students enrolled in a course'''
# fetch schedule ids containing the course listed
c_key = ndb.Key(Course, request.course_id)
query = Schedule.query(Schedule.course == c_key)
schedule_keys = []
for key in query.iter(keys_only=True):
schedule_keys.append(key)
# query for enrollments with matching schedule_keys
query = Enrollment.query(Enrollment.schedule.IN(schedule_keys))
print(
"view_students_in_course method: going to convert query to student names message"
)
return self.enrollmentToStudentsMessage(query)
def deleteCourse(self, course_id):
'''Delete a course given course ID. Delete course from Schedule first.'''
try:
response = ""
# Creating the key for given course id
c_key = ndb.Key(Course, course_id)
# Check if course exists
if c_key.get():
'''Dependency Check'''
# Check if course exists in schedule
query = Schedule.query(Schedule.course == c_key)
if query.get():
# course exists in schedule. Invoke dependency error
response = R_DEP_ERR_DELCHILD.format("Schedule", "Course")
else:
# Fetching and deleting the entity with given course_id
c_key.delete()
response = R_SUCC_DEL.format("Course", str(c_key))
except Exception, e:
response = R_SERV_ERR.format(str(e))
def insertSchedule(self, request):
''' insert a course schedule for given quarter. Require course ID, quarter and year.'''
response = ""
# Validate course id
c_key = ndb.Key(Course, request.course_id)
# Check if entity exists
if c_key.get():
# fetch the respective dept for that course id
d_key = c_key.get().department
# check for duplicate entries
query = Schedule.query(Schedule.course == c_key,
Schedule.quarter == request.quarter,
Schedule.year == request.year)
if not query.get():
# insert schedule
response = self.upsertSchedule(request, d_key, ADD_ID)
else:
response = STORED_RESPONSES.items[DUPLICATE_ID]
else:
response = STORED_RESPONSES.items[INV_COURSE_ID]
return response
def deleteCourse(self, request):
'''Delete a course given course ID. Delete course from Schedule first.'''
try:
response = ""
# Creating the key for given course id
c_key = ndb.Key(Course, request.id)
# Check if course exists
if c_key.get():
'''Dependency Check'''
# Check if course exists in schedule
query = Schedule.query(Schedule.course == c_key)
if query.get():
# course exists in schedule. Invoke dependency error
response = STORED_RESPONSES.items[DEP_ERR_COURSE_ID]
else:
# Fetching and deleting the entity with given course_id
c_key.delete()
response = STORED_RESPONSES.items[DELETE_ID]
return response
except:
raise endpoints.EndpointsErrorMessage(
'Unable to delete course entity. Please try again later. ')
def getSchedule(self, course_key, quarter, year):
return Schedule.query(Schedule.course == course_key,
Schedule.quarter == quarter,
Schedule.year == year)