Accommodation Section

The accommodation section is a built-in hostel management system. African universities usually run their own student hostels which are built on their huge university campuses. They combine the booking of beds with the registration process. There are two major use cases. Students either have to book a bed space before they can continue with the registration, or they are only allowed to book, if they have reached a certain registration state. In the first case, the university requires students to stay on campus. They usually have enough beds for all of their students and need to fill up the hostels. In the second case, bed space is limited. Since accommodation on campus is usually very reasonable and much safer than on the free market outside, students prefer to stay on campus. If bed allocation e.g. requires the payment of school fees, the university benefits from bed shortage, because students are forced to pay in order to get the highly coveted hostel bed.

From the database’s point of view, the accommodation section is a container of type HostelsContainer with id hostels, which is located in the IUniversity instance. It contains hostels (instances of IHostel) which again contain the beds (instances of IBed).

The treelike storage of objects in the accommodation section can be figured as follows:

Accommodation Section (HostelsContainer)
|
+---> Hostel
      |
      +---> Bed

Interfaces

IHostelsContainer

The unique hostels container serves also as a configuration object. It defines for which academic session booking is enabled. The student’s current_session must match the accommodation_session. It also defines the booking period and the registration workflow states for which booking is allowed, see Bed Tickets. The only property attribute is expired which returns True if the current datetime is within the booking period.

class IHostelsContainer(IKofaObject):
    """A container for hostel objects.
    """

    expired = Attribute('True if current datetime is in application period.')
    statistics = Attribute('Bed category statistics')

    startdate = schema.Datetime(
        title = _(u'Hostel Allocation Start Date'),
        required = False,
        description = _('Example: ') + u'2011-12-01 18:30:00+01:00',
        )

    enddate = schema.Datetime(
        title = _(u'Hostel Allocation Closing Date'),
        required = False,
        description = _('Example: ') + u'2011-12-31 23:59:59+01:00',
        )

    accommodation_session = schema.Choice(
        title = _(u'Booking Session'),
        source = academic_sessions_vocab,
        #default = datetime.now().year,
        required = False,
        readonly = False,
        )

    accommodation_states = schema.List(
        title = _(u'Allowed States'),
        value_type = schema.Choice(
            vocabulary = registration_states_vocab,
            ),
        defaultFactory=list,
        )

    allocation_expiration = schema.Int(
        title = _(u'Allocation Expiration Time (days)'),
        description = _(
            'Number of days after which allocation is being annulled'),
        required = False,
        )

    def clearAllHostels():
        """Clear all hostels.
        """

    def addHostel(hostel):
        """Add a hostel.
        """

    def releaseExpiredAllocations(n):
        """Release bed if bed allocation has expired. Allocation expires
        after `n` days if maintenance fee has not been paid.
        """

    def writeLogMessage(view, message):
        """Add an INFO message to hostels.log.
        """

IHostel

The hostels container contains the various Hostel objects. Hostels are buildings with blocks, floors rooms and beds. When adding a hostel, the form page is requesting the hostel’s name. The hostel_id is derived from the name by applying lower().replace(' ','-').replace('_','-') to it. As usual, the id will be omitted in manage forms and can thus not be changed after hostel creation.

The add and manage form pages let us define the ‘dimensions’ of the hostel and configure blocks with their assignment to either female or male students. And they are requesting the number of floors per block as well as the number of rooms per floor. All blocks have the same number of floors with a fixed number of rooms and a fixed number of beds per room. If beds or even entire rooms do not exist on a floor, these beds must be later marked reserved, so that they are skipped during the automatic allocation process, see below.

Note

Blocks for either female or male students? Does Kofa’s hostel management accommodate girls and boys strictly separately? No, it doesn’t. Blocks are not necessarily real buildings. They can be used as virtual subunits. If the entire hostel has only one block, then yes, either only female or only male students can be hosted in such a hostel. If two blocks are configured (one for male and one for female students), beds of the same room can be assigned twice, once in Block A and a second time in Block B. Consequently, one bed of such a bed pair must be set ‘reserved’ (see below) to avoid double allocation. In other words, there is always a trick which allows even such uncommon configurations. Not many universities will allow girls and boys to stay in the same room.

class IHostel(IKofaObject):
    """Representation of a hostel.
    """

    bed_statistics = Attribute('Number of booked and total beds')

    def clearHostel():
        """Remove all beds.
        """

    def updateBeds():
        """Fill hostel with beds or update beds.
        """

    hostel_id = schema.TextLine(
        title = _(u'Hostel Id'),
        )

    sort_id = schema.Int(
        title = _(u'Sort Id'),
        required = True,
        default = 10,
        constraint=validate_sort_id,
        )

    hostel_name = schema.TextLine(
        title = _(u'Hostel Name'),
        required = True,
        default = u'Hall 1',
        )

    floors_per_block = schema.Int(
        title = _(u'Floors per Block'),
        required = True,
        default = 1,
        )

    rooms_per_floor = schema.Int(
        title = _(u'Rooms per Floor'),
        required = True,
        default = 2,
        )

    blocks_for_female = schema.List(
        title = _(u'Blocks for Female Students'),
        value_type = schema.Choice(
            vocabulary = blocks
            ),
        defaultFactory=list,
        )

    blocks_for_male = schema.List(
        title = _(u'Blocks for Male Students'),
        value_type = schema.Choice(
            vocabulary = blocks
            ),
        defaultFactory=list,
        )

    beds_for_pre= schema.List(
        title = _(u'Beds for Pre-Study Students'),
        value_type = schema.Choice(
            vocabulary = bed_letters
            ),
        defaultFactory=list,
        )

    beds_for_fresh = schema.List(
        title = _(u'Beds for Fresh Students'),
        value_type = schema.Choice(
            vocabulary = bed_letters
            ),
        defaultFactory=list,
        )

    beds_for_returning = schema.List(
        title = _(u'Beds for Returning Students'),
        value_type = schema.Choice(
            vocabulary = bed_letters
            ),
        defaultFactory=list,
        )

    beds_for_final = schema.List(
        title = _(u'Beds for Final Year Students'),
        value_type = schema.Choice(
            vocabulary = bed_letters
            ),
        defaultFactory=list,
        )

    beds_for_all = schema.List(
        title = _(u'Beds without category'),
        value_type = schema.Choice(
            vocabulary = bed_letters
            ),
        defaultFactory=list,
        )

    special_handling = schema.Choice(
        title = _(u'Special Handling'),
        source = SpecialHandlingSource(),
        required = True,
        default = u'regular',
        )

    maint_fee = schema.Float(
        title = _(u'Rent'),
        default = 0.0,
        required = False,
        )

    @invariant
    def blocksOverlap(hostel):
        bfe = hostel.blocks_for_female
        bma = hostel.blocks_for_male
        if set(bfe).intersection(set(bma)):
            raise Invalid(_('Female and male blocks overlap.'))

    @invariant
    def bedsOverlap(hostel):
        beds = (hostel.beds_for_fresh +
                hostel.beds_for_returning +
                hostel.beds_for_final +
                hostel.beds_for_pre +
                hostel.beds_for_all)
        if len(beds) != len(set(beds)):
            raise Invalid(_('Bed categories overlap.'))

    def writeLogMessage(view, message):
        """Add an INFO message to hostels.log.
        """

Beds can be dedicated to pre-study students, fresh students (entry_session and the hostels container’s accommodation_session correspond), final-year students (current_level and the certificate’s end_level correspond, or is even higher) and returning students (non-fresh and non-final-year students). Or they can be made bookable for all students (beds without category). The latter bed type can be configured but is not being used in the base package by getAccommodationDetails, the method which determines the appropriate bed type of the student.

Usually, not every student can be accommodated in every hostel. Faculties are sometimes far apart and do manage their own student hostels. These hostels require a ‘special handling’ in getAccommodationDetails. The special handling code must be set on the add and manage form pages of hostels.

The interface defines also two schema invariants (invariant-decorated methods). These methods validate one or more depending schema fields. In our case, the methods take care that blocks and beds are not assigned twice.

All the parameters above define the construction rules for beds when filling the hostel with beds, which is done by the updateBeds method described further below.

IBed

class IBed(IKofaObject):
    """Representation of a bed.
    """

    coordinates = Attribute('Coordinates tuple derived from bed_id')
    hall = Attribute('Hall id, for exporter only')
    block = Attribute('Block letter, for exporter only')
    room = Attribute('Room number, for exporter only')
    bed = Attribute('Bed letter, for exporter only')
    special_handling = Attribute('Special handling code, for exporter only')
    sex = Attribute('Sex, for exporter only')
    bt = Attribute('Last part of bed type, for exporter only')

    def bookBed(student_id):
        """Book a bed for a student.
        """

    def switchReservation():
        """Reserves bed or relases reserved bed respectively.
        """

    def releaseBedIfMaintenanceNotPaid():
        """Release bed if maintenance fee has not been paid on time.
        Reserve bed so that it cannot be automatically booked by someone else.
        """

    bed_id = schema.TextLine(
        title = _(u'Bed Id'),
        required = True,
        default = u'',
        )

    bed_type = schema.TextLine(
        title = _(u'Bed Type'),
        required = True,
        default = u'',
        )

    bed_number = schema.Int(
        title = _(u'Bed Number'),
        required = True,
        )

    owner = schema.TextLine(
        title = _(u'Owner (Student)'),
        description = _('Enter valid student id.'),
        required = True,
        default = u'',
        )

    @invariant
    def allowed_owners(bed):
        if bed.owner == NOT_OCCUPIED:
            return
        catalog = getUtility(ICatalog, name='students_catalog')
        accommodation_span = getUtility(IStudentsUtils).ACCOMMODATION_SPAN
        accommodation_session = getSite()['hostels'].accommodation_session
        students = catalog.searchResults(current_session=(
            accommodation_session-accommodation_span,accommodation_session))
        student_ids = [student.student_id for student in students]
        if not bed.owner in student_ids:
            raise Invalid(_(
                "Either student does not exist or student "
                "is not eligible to book accommodation."))
        catalog = getUtility(ICatalog, name='beds_catalog')
        beds = catalog.searchResults(owner=(bed.owner,bed.owner))
        if len(beds):
            allocated_bed = [bed.bed_id for bed in beds][0]
            raise Invalid(_(
                "This student resides in bed ${a}.",
                mapping = {'a':allocated_bed}))

    def writeLogMessage(view, message):
        """Add an INFO message to hostels.log.
        """

The bed_id contains the ‘coordinates’ of the bed. It tells us precisely in which hostel, in which block, on which floor and in which room the bed can be found. The bed id is composed as follows: [hostel id]_[block letter]_[room number]_[bed letter]. The room number contains the floor level: room_nr = floor*100 + room. Example: hall-1_A_101_C means that the bed is located in Hostel 1, Block A, 1st Floor, Room 101 (or 1) and labelled with ‘C’.

The bed_type attribute is similarly being constructed. It describes which kind of student can be allocated: [special handling code]_[sex]_[stage]. Example: regular_female_re means that this bed can be booked by regular female returning students. Other stages are: fr (fresh), pr (pre-study), fi (final-year) and all (all students).

Beds of each hostel are consecutively numbered (bed_number).

Except for owner, all attributes of bed objects are being determined by the system, no matter if they are property or schema field attrributes. They can neither be edited nor imported (there is no batch processor for beds). The owner attribute contains the student id, if the bed is occupied. This attribute is either set by Kofa when the student creates a bed ticket (see Bed Tickets), or can be set via the BedManageFormPage, see below. The allowed_owners schema invariant ensures (1) that the selected user exists, (2) that the student’s current session corresponds with the accommodation session and (3) that the student doesn’t reside in another bed.

Browser Pages

See also

Manage Hostel Python Test

Update Beds

Hostels are empty after creation and configuration. They do not contain any bed. The hostel’s Hostel.updateBeds method must be called to fill the hostel with beds according to the hostel’s configuration parameters. This is done by the same-named action of the HostelManageFormPage. Hostel.updateBeds iterates over all block letters, floor levels, room numbers and bed letters, which have been configured on the HostelManageFormPage. In each bed letter iteration loop a bed is added and the bed_id, bed type as well as the consecutive bed_number are determined and stored with the bed.

As the method’s name already promises, it does not only add beds to an empty hostel container, but also updates existing beds after re-configuration. It does this by removing all empty beds before the iteration starts. Occupied beds remain in the hostel but get the bed number 9999. When iterating over the newly configured blocks, floors, rooms and bed letters, Kofa checks first, if the bed belongs to the group of remaining beds, which could not be removed because they are occupied. If so, the bed type is adjusted and the bed number changed. The bed remains occupied by the same student, no matter if the student meets the newly configured conditions or not.

It might happen that e.g. a room for male students is converted into a room for female students, but a male student still resides in this room. This has to be checked and the student has to be relocated manually, see Student Relocation. Moreover, due to the reconfiguration of the hostel, an occupied bed may no longer exist or offered for booking. This is then indicated by the bed number 9999. Also these students must be relocated manually.

Switch Reservations

Beds can be blocked by switching ther reservation status. The switch replaces the stage part of bed_type by _reserved. Example: regular_female_re becomes regular_female_reserved. Switching again, reverts this process.

Reserved beds won’t be allocated automatically. The beds remain empty during the hostel booking period. Students can only be allocated manually to reserved beds, which is done via the BedManageFormPage, see below.

Release Beds

Releasing a bed does not simply mean clearing the owner attribute of the bed object. The student has to be notified that booking has been cancelled. This is done by replacing the bed_coordinates of the student’s bed ticket. Instead of the coordinates, the student will read: -- booking cancelled on <datetime of cancellation> --.

Manage Bed

Not many things can be managed on this form page. As mentioned above, only the owner attribute can be changed by entering a student id. The id is being validated by a schema invariant. The manage form page cannot be accessed, if a student has aleady been allocated. Beds must be released first, before they can be allocated to other students.