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# Author: Matt Giuca, Will Grant
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"""Database utilities and content classes.
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Database Classes and Utilities for Storm ORM
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This module provides all of the classes which map to database tables.
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It also provides miscellaneous utility functions for database interaction.
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from storm.locals import create_database, Store, Int, Unicode, DateTime, \
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Reference, ReferenceSet, Bool, Storm, Desc
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from storm.expr import Select, Max
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from storm.exceptions import NotOneError, IntegrityError
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from ivle.worksheet.rst import rst
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__all__ = ['get_store',
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'Subject', 'Semester', 'Offering', 'Enrolment',
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'ProjectSet', 'Project', 'ProjectGroup', 'ProjectGroupMembership',
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'Assessed', 'ProjectSubmission', 'ProjectExtension',
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'Exercise', 'Worksheet', 'WorksheetExercise',
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'ExerciseSave', 'ExerciseAttempt',
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'TestCase', 'TestSuite', 'TestSuiteVar'
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'AlreadyEnrolledError'
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def _kwarg_init(self, **kwargs):
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% (self.__class__.__name__, k))
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setattr(self, k, v)
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def get_conn_string(config):
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"""Create a Storm connection string to the IVLE database
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@param config: The IVLE configuration.
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if config['database']['username']:
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clusterstr += config['database']['username']
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if config['database']['password']:
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clusterstr += ':' + config['database']['password']
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host = config['database']['host'] or 'localhost'
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port = config['database']['port'] or 5432
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clusterstr += '%s:%d' % (host, port)
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return "postgres://%s/%s" % (clusterstr, config['database']['name'])
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def get_store(config):
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"""Create a Storm store connected to the IVLE database.
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@param config: The IVLE configuration.
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return Store(create_database(get_conn_string(config)))
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def get_conn_string():
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Returns the Storm connection string, generated from the conf file.
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return "postgres://%s:%s@%s:%d/%s" % (ivle.conf.db_user,
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ivle.conf.db_password, ivle.conf.db_host, ivle.conf.db_port,
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Open a database connection and transaction. Return a storm.store.Store
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instance connected to the configured IVLE database.
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return Store(create_database(get_conn_string()))
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"""An IVLE user account."""
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Represents an IVLE user.
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__storm_table__ = "login"
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id = Int(primary=True, name="loginid")
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passhash = Unicode()
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pass_exp = DateTime()
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'''A sanely ordered list of all of the user's enrolments.'''
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return self._get_enrolments(False)
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def get_projects(self, offering=None, active_only=True):
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"""Find projects that the user can submit.
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This will include projects for offerings in which the user is
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enrolled, as long as the project is not in a project set which has
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groups (ie. if maximum number of group members is 0).
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@param active_only: Whether to only search active offerings.
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@param offering: An optional offering to restrict the search to.
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return Store.of(self).find(Project,
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Project.project_set_id == ProjectSet.id,
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ProjectSet.max_students_per_group == None,
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ProjectSet.offering_id == Offering.id,
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(offering is None) or (Offering.id == offering.id),
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Semester.id == Offering.semester_id,
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(not active_only) or (Semester.state == u'current'),
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Enrolment.offering_id == Offering.id,
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Enrolment.user_id == self.id)
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def hash_password(password):
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"""Hash a password with MD5."""
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return hashlib.md5(password).hexdigest()
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return md5.md5(password).hexdigest()
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def get_by_login(cls, store, login):
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"""Find a user in a store by login name."""
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Get the User from the db associated with a given store and
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return store.find(cls, cls.login == unicode(login)).one()
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def get_permissions(self, user):
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"""Determine privileges held by a user over this object.
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If the user requesting privileges is this user or an admin,
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they may do everything. Otherwise they may do nothing.
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if user and user.admin or user is self:
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return set(['view', 'edit', 'submit_project'])
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if user and user.rolenm == 'admin' or user is self:
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return set(['view', 'edit'])
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# SUBJECTS AND ENROLMENTS #
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class Subject(Storm):
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"""A subject (or course) which is run in some semesters."""
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__storm_table__ = "subject"
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id = Int(primary=True, name="subjectid")
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return "<%s '%s'>" % (type(self).__name__, self.short_name)
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def get_permissions(self, user):
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"""Determine privileges held by a user over this object.
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If the user requesting privileges is an admin, they may edit.
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Otherwise they may only read.
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if user is not None:
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perms.add('view')
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if user.rolenm == 'admin':
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def active_offerings(self):
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"""Find active offerings for this subject.
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Return a sequence of currently active offerings for this subject
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(offerings whose semester.state is "current"). There should be 0 or 1
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elements in this sequence, but it's possible there are more.
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return self.offerings.find(Offering.semester_id == Semester.id,
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Semester.state == u'current')
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def offering_for_semester(self, year, semester):
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"""Get the offering for the given year/semester, or None.
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@param year: A string representation of the year.
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@param semester: A string representation of the semester.
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return self.offerings.find(Offering.semester_id == Semester.id,
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Semester.year == unicode(year),
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Semester.semester == unicode(semester)).one()
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class Semester(Storm):
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"""A semester in which subjects can be run."""
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__storm_table__ = "semester"
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id = Int(primary=True, name="semesterid")
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semester = Unicode()
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offerings = ReferenceSet(id, 'Offering.semester_id')
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enrolments = ReferenceSet(id,
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'Offering.semester_id',
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'Enrolment.offering_id')
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__init__ = _kwarg_init
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project_sets = ReferenceSet(id, 'ProjectSet.offering_id')
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worksheets = ReferenceSet(id,
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'Worksheet.offering_id',
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__init__ = _kwarg_init
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def __repr__(self):
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return "<%s %r in %r>" % (type(self).__name__, self.subject,
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def enrol(self, user, role=u'student'):
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"""Enrol a user in this offering.
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Enrolments handle both the staff and student cases. The role controls
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the privileges granted by this enrolment.
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enrolment = Store.of(self).find(Enrolment,
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Enrolment.user_id == user.id,
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Enrolment.offering_id == self.id).one()
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if enrolment is None:
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enrolment = Enrolment(user=user, offering=self)
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self.enrolments.add(enrolment)
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enrolment.active = True
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enrolment.role = role
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def unenrol(self, user):
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'''Unenrol a user from this offering.'''
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enrolment = Store.of(self).find(Enrolment,
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Enrolment.user_id == user.id,
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Enrolment.offering_id == self.id).one()
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Store.of(enrolment).remove(enrolment)
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def get_permissions(self, user):
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enrolment = self.get_enrolment(user)
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if enrolment or user.admin:
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if (enrolment and enrolment.role in (u'tutor', u'lecturer')) \
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def get_enrolment(self, user):
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"""Find the user's enrolment in this offering."""
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enrolment = self.enrolments.find(user=user).one()
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def get_members_by_role(self, role):
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return Store.of(self).find(User,
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Enrolment.user_id == User.id,
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Enrolment.offering_id == self.id,
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Enrolment.role == role
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return self.get_members_by_role(u'student')
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def enrol(self, user):
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'''Enrol a user in this offering.'''
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# We'll get a horrible database constraint violation error if we try
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# to add a second enrolment.
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if Store.of(self).find(Enrolment,
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Enrolment.user_id == user.id,
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Enrolment.offering_id == self.id).count() == 1:
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raise AlreadyEnrolledError()
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e = Enrolment(user=user, offering=self, active=True)
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self.enrolments.add(e)
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class Enrolment(Storm):
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"""An enrolment of a user in an offering.
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This represents the roles of both staff and students.
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__storm_table__ = "enrolment"
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__storm_primary__ = "user_id", "offering_id"
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return "<%s %d in %r>" % (type(self).__name__, self.id,
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def get_permissions(self, user):
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return self.offering.get_permissions(user)
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"""Get the entities (groups or users) assigned to submit this project.
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This will be a Storm ResultSet.
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#If its a solo project, return everyone in offering
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if self.max_students_per_group is None:
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return self.offering.students
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return self.project_groups
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class Project(Storm):
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"""A student project for which submissions can be made."""
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__storm_table__ = "project"
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id = Int(name="projectid", primary=True)
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short_name = Unicode()
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synopsis = Unicode()
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project_set_id = Int(name="projectsetid")
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project_set = Reference(project_set_id, ProjectSet.id)
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deadline = DateTime()
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assesseds = ReferenceSet(id, 'Assessed.project_id')
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submissions = ReferenceSet(id,
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'Assessed.project_id',
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'ProjectSubmission.assessed_id')
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__init__ = _kwarg_init
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def __repr__(self):
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return "<%s '%s' in %r>" % (type(self).__name__, self.short_name,
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return "<%s '%s' in %r>" % (type(self).__name__, self.synopsis,
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self.project_set.offering)
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def can_submit(self, principal):
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return (self in principal.get_projects() and
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self.deadline > datetime.datetime.now())
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def submit(self, principal, path, revision, who):
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"""Submit a Subversion path and revision to a project.
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@param principal: The owner of the Subversion repository, and the
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entity on behalf of whom the submission is being made
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@param path: A path within that repository to submit.
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@param revision: The revision of that path to submit.
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@param who: The user who is actually making the submission.
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if not self.can_submit(principal):
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raise Exception('cannot submit')
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a = Assessed.get(Store.of(self), principal, self)
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ps = ProjectSubmission()
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ps.revision = revision
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ps.date_submitted = datetime.datetime.now()
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def get_permissions(self, user):
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return self.project_set.offering.get_permissions(user)
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def latest_submissions(self):
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"""Return the latest submission for each Assessed."""
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return Store.of(self).find(ProjectSubmission,
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Assessed.project_id == self.id,
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ProjectSubmission.assessed_id == Assessed.id,
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ProjectSubmission.date_submitted == Select(
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Max(ProjectSubmission.date_submitted),
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ProjectSubmission.assessed_id == Assessed.id,
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tables=ProjectSubmission
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class ProjectGroup(Storm):
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"""A group of students working together on a project."""
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__storm_table__ = "project_group"
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id = Int(name="groupid", primary=True)
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return "<%s %s in %r>" % (type(self).__name__, self.name,
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self.project_set.offering)
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def display_name(self):
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"""Returns the "nice name" of the user or group."""
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def short_name(self):
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"""Returns the database "identifier" name of the user or group."""
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def get_projects(self, offering=None, active_only=True):
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'''Find projects that the group can submit.
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This will include projects in the project set which owns this group,
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unless the project set disallows groups (in which case none will be
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@param active_only: Whether to only search active offerings.
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@param offering: An optional offering to restrict the search to.
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return Store.of(self).find(Project,
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Project.project_set_id == ProjectSet.id,
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ProjectSet.id == self.project_set.id,
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ProjectSet.max_students_per_group != None,
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ProjectSet.offering_id == Offering.id,
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(offering is None) or (Offering.id == offering.id),
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Semester.id == Offering.semester_id,
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(not active_only) or (Semester.state == u'current'))
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def get_permissions(self, user):
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if user.admin or user in self.members:
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return set(['submit_project'])
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class ProjectGroupMembership(Storm):
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"""A student's membership in a project group."""
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__storm_table__ = "group_member"
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__storm_primary__ = "user_id", "project_group_id"
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return "<%s %r in %r>" % (type(self).__name__, self.user,
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self.project_group)
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class Assessed(Storm):
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"""A composite of a user or group combined with a project.
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Each project submission and extension refers to an Assessed. It is the
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sole specifier of the repository and project.
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__storm_table__ = "assessed"
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id = Int(name="assessedid", primary=True)
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user_id = Int(name="loginid")
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user = Reference(user_id, User.id)
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project_group_id = Int(name="groupid")
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project_group = Reference(project_group_id, ProjectGroup.id)
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project_id = Int(name="projectid")
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project = Reference(project_id, Project.id)
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extensions = ReferenceSet(id, 'ProjectExtension.assessed_id')
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submissions = ReferenceSet(id, 'ProjectSubmission.assessed_id')
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return "<%s %r in %r>" % (type(self).__name__,
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self.user or self.project_group, self.project)
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"""True if the Assessed is a group, False if it is a user."""
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return self.project_group is not None
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return self.project_group or self.user
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def get(cls, store, principal, project):
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"""Find or create an Assessed for the given user or group and project.
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@param principal: The user or group.
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@param project: The project.
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if t not in (User, ProjectGroup):
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raise AssertionError('principal must be User or ProjectGroup')
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(t is User) or (cls.project_group_id == principal.id),
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(t is ProjectGroup) or (cls.user_id == principal.id),
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Project.id == project.id).one()
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a.project_group = principal
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class ProjectExtension(Storm):
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"""An extension granted to a user or group on a particular project.
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The user or group and project are specified by the Assessed.
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__storm_table__ = "project_extension"
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id = Int(name="extensionid", primary=True)
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assessed_id = Int(name="assessedid")
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assessed = Reference(assessed_id, Assessed.id)
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deadline = DateTime()
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approver_id = Int(name="approver")
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approver = Reference(approver_id, User.id)
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class ProjectSubmission(Storm):
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"""A submission from a user or group repository to a particular project.
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The content of a submission is a single path and revision inside a
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repository. The repository is that owned by the submission's user and
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group, while the path and revision are explicit.
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The user or group and project are specified by the Assessed.
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__storm_table__ = "project_submission"
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id = Int(name="submissionid", primary=True)
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assessed_id = Int(name="assessedid")
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assessed = Reference(assessed_id, Assessed.id)
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submitter_id = Int(name="submitter")
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submitter = Reference(submitter_id, User.id)
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date_submitted = DateTime()
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# WORKSHEETS AND EXERCISES #
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class Exercise(Storm):
722
"""An exercise for students to complete in a worksheet.
724
An exercise may be present in any number of worksheets.
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__storm_table__ = "exercise"
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id = Unicode(primary=True, name="identifier")
730
description = Unicode()
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worksheet_exercises = ReferenceSet(id,
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'WorksheetExercise.exercise_id')
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# Note: Table "problem" is called "Exercise" in the Object layer, since
386
# it's called that everywhere else.
387
__storm_table__ = "problem"
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id = Int(primary=True, name="problemid")
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name = Unicode(name="identifier")
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worksheets = ReferenceSet(id,
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'WorksheetExercise.exercise_id',
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test_suites = ReferenceSet(id,
746
'TestSuite.exercise_id',
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__init__ = _kwarg_init
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def __repr__(self):
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402
return "<%s %s>" % (type(self).__name__, self.name)
754
def get_permissions(self, user):
761
elif u'lecturer' in set((e.role for e in user.active_enrolments)):
764
elif u'tutor' in set((e.role for e in user.active_enrolments)):
770
def get_description(self):
771
"""Return the description interpreted as reStructuredText."""
772
return rst(self.description)
775
"""Deletes the exercise, providing it has no associated worksheets."""
776
if (self.worksheet_exercises.count() > 0):
777
raise IntegrityError()
778
for suite in self.test_suites:
780
Store.of(self).remove(self)
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def get_by_name(cls, store, name):
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Get the Exercise from the db associated with a given store and name.
408
If the exercise is not in the database, creates it and inserts it
411
ex = store.find(cls, cls.name == unicode(name)).one()
414
ex = Exercise(name=unicode(name))
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class Worksheet(Storm):
783
"""A worksheet with exercises for students to complete.
785
Worksheets are owned by offerings.
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__storm_table__ = "worksheet"
790
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id = Int(primary=True, name="worksheetid")
791
offering_id = Int(name="offeringid")
792
identifier = Unicode()
423
# XXX subject is not linked to a Subject object. This is a property of
424
# the database, and will be refactored.
426
name = Unicode(name="identifier")
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assessable = Bool()
799
attempts = ReferenceSet(id, "ExerciseAttempt.worksheetid")
800
offering = Reference(offering_id, 'Offering.id')
802
all_worksheet_exercises = ReferenceSet(id,
430
exercises = ReferenceSet(id,
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'WorksheetExercise.worksheet_id',
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'WorksheetExercise.exercise_id',
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# Use worksheet_exercises to get access to the WorksheetExercise objects
435
# binding worksheets to exercises. This is required to access the
437
worksheet_exercises = ReferenceSet(id,
803
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'WorksheetExercise.worksheet_id')
805
# Use worksheet_exercises to get access to the *active* WorksheetExercise
806
# objects binding worksheets to exercises. This is required to access the
810
def worksheet_exercises(self):
811
return self.all_worksheet_exercises.find(active=True)
813
440
__init__ = _kwarg_init
815
442
def __repr__(self):
816
443
return "<%s %s>" % (type(self).__name__, self.name)
818
def remove_all_exercises(self):
819
"""Remove all exercises from this worksheet.
445
# XXX Refactor this - make it an instance method of Subject rather than a
446
# class method of Worksheet. Can't do that now because Subject isn't
447
# linked referentially to the Worksheet.
449
def get_by_name(cls, store, subjectname, worksheetname):
451
Get the Worksheet from the db associated with a given store, subject
452
name and worksheet name.
454
return store.find(cls, cls.subject == unicode(subjectname),
455
cls.name == unicode(worksheetname)).one()
457
def remove_all_exercises(self, store):
459
Remove all exercises from this worksheet.
821
460
This does not delete the exercises themselves. It just removes them
822
461
from the worksheet.
824
store = Store.of(self)
825
for ws_ex in self.all_worksheet_exercises:
826
if ws_ex.saves.count() > 0 or ws_ex.attempts.count() > 0:
827
raise IntegrityError()
828
463
store.find(WorksheetExercise,
829
464
WorksheetExercise.worksheet == self).remove()
831
def get_permissions(self, user):
832
return self.offering.get_permissions(user)
835
"""Returns the xml of this worksheet, converts from rst if required."""
836
if self.format == u'rst':
837
ws_xml = rst(self.data)
843
"""Deletes the worksheet, provided it has no attempts on any exercises.
845
Returns True if delete succeeded, or False if this worksheet has
846
attempts attached."""
847
for ws_ex in self.all_worksheet_exercises:
848
if ws_ex.saves.count() > 0 or ws_ex.attempts.count() > 0:
849
raise IntegrityError()
851
self.remove_all_exercises()
852
Store.of(self).remove(self)
854
466
class WorksheetExercise(Storm):
855
"""A link between a worksheet and one of its exercises.
857
These may be marked optional, in which case the exercise does not count
858
for marking purposes. The sequence number is used to order the worksheet
862
__storm_table__ = "worksheet_exercise"
864
id = Int(primary=True, name="ws_ex_id")
467
__storm_table__ = "worksheet_problem"
468
__storm_primary__ = "worksheet_id", "exercise_id"
866
470
worksheet_id = Int(name="worksheetid")
867
471
worksheet = Reference(worksheet_id, Worksheet.id)
868
exercise_id = Unicode(name="exerciseid")
472
exercise_id = Int(name="problemid")
869
473
exercise = Reference(exercise_id, Exercise.id)
870
474
optional = Bool()
874
saves = ReferenceSet(id, "ExerciseSave.ws_ex_id")
875
attempts = ReferenceSet(id, "ExerciseAttempt.ws_ex_id")
877
476
__init__ = _kwarg_init
879
478
def __repr__(self):
880
479
return "<%s %s in %s>" % (type(self).__name__, self.exercise.name,
881
self.worksheet.identifier)
883
def get_permissions(self, user):
884
return self.worksheet.get_permissions(user)
887
482
class ExerciseSave(Storm):
888
"""A potential exercise solution submitted by a user for storage.
890
This is not an actual tested attempt at an exercise, it's just a save of
894
__storm_table__ = "exercise_save"
895
__storm_primary__ = "ws_ex_id", "user_id"
897
ws_ex_id = Int(name="ws_ex_id")
898
worksheet_exercise = Reference(ws_ex_id, "WorksheetExercise.id")
484
Represents a potential solution to an exercise that a user has submitted
485
to the server for storage.
486
A basic ExerciseSave is just the current saved text for this exercise for
487
this user (doesn't count towards their attempts).
488
ExerciseSave may be extended with additional semantics (such as
491
__storm_table__ = "problem_save"
492
__storm_primary__ = "exercise_id", "user_id", "date"
494
exercise_id = Int(name="problemid")
495
exercise = Reference(exercise_id, Exercise.id)
900
496
user_id = Int(name="loginid")
901
497
user = Reference(user_id, User.id)
902
498
date = DateTime()
909
505
self.exercise.name, self.user.login, self.date.strftime("%c"))
911
507
class ExerciseAttempt(ExerciseSave):
912
"""An attempt at solving an exercise.
914
This is a special case of ExerciseSave, used when the user submits a
915
candidate solution. Like an ExerciseSave, it constitutes exercise solution
918
In addition, it contains information about the result of the submission:
920
- complete - True if this submission was successful, rendering this
921
exercise complete for this user in this worksheet.
922
- active - True if this submission is "active" (usually true).
923
Submissions may be de-activated by privileged users for
924
special reasons, and then they won't count (either as a
925
penalty or success), but will still be stored.
928
__storm_table__ = "exercise_attempt"
929
__storm_primary__ = "ws_ex_id", "user_id", "date"
509
An ExerciseAttempt is a special case of an ExerciseSave. Like an
510
ExerciseSave, it constitutes exercise solution data that the user has
511
submitted to the server for storage.
512
In addition, it contains additional information about the submission.
513
complete - True if this submission was successful, rendering this exercise
514
complete for this user.
515
active - True if this submission is "active" (usually true). Submissions
516
may be de-activated by privileged users for special reasons, and then
517
they won't count (either as a penalty or success), but will still be
520
__storm_table__ = "problem_attempt"
521
__storm_primary__ = "exercise_id", "user_id", "date"
931
523
# The "text" field is the same but has a different name in the DB table
932
524
# for some reason.
937
529
def get_permissions(self, user):
938
530
return set(['view']) if user is self.user else set()
940
class TestSuite(Storm):
941
"""A container to group an exercise's test cases.
943
The test suite contains some information on how to test. The function to
944
test, variables to set and stdin data are stored here.
947
__storm_table__ = "test_suite"
948
__storm_primary__ = "exercise_id", "suiteid"
951
exercise_id = Unicode(name="exerciseid")
952
description = Unicode()
956
exercise = Reference(exercise_id, Exercise.id)
957
test_cases = ReferenceSet(suiteid, 'TestCase.suiteid', order_by="seq_no")
958
variables = ReferenceSet(suiteid, 'TestSuiteVar.suiteid', order_by='arg_no')
961
"""Delete this suite, without asking questions."""
962
for vaariable in self.variables:
964
for test_case in self.test_cases:
966
Store.of(self).remove(self)
968
class TestCase(Storm):
969
"""A container for actual tests (see TestCasePart), inside a test suite.
971
It is the lowest level shown to students on their pass/fail status."""
973
__storm_table__ = "test_case"
974
__storm_primary__ = "testid", "suiteid"
978
suite = Reference(suiteid, "TestSuite.suiteid")
981
test_default = Unicode()
984
parts = ReferenceSet(testid, "TestCasePart.testid")
986
__init__ = _kwarg_init
989
for part in self.parts:
991
Store.of(self).remove(self)
993
class TestSuiteVar(Storm):
994
"""A variable used by an exercise test suite.
996
This may represent a function argument or a normal variable.
999
__storm_table__ = "suite_variable"
1000
__storm_primary__ = "varid"
1004
var_name = Unicode()
1005
var_value = Unicode()
1006
var_type = Unicode()
1009
suite = Reference(suiteid, "TestSuite.suiteid")
1011
__init__ = _kwarg_init
1014
Store.of(self).remove(self)
1016
class TestCasePart(Storm):
1017
"""An actual piece of code to test an exercise solution."""
1019
__storm_table__ = "test_case_part"
1020
__storm_primary__ = "partid"
1025
part_type = Unicode()
1026
test_type = Unicode()
1028
filename = Unicode()
1030
test = Reference(testid, "TestCase.testid")
1032
__init__ = _kwarg_init
1035
Store.of(self).remove(self)
added
removed
ivle/database.py
