Building your world - part six: extending the Room class to display the links

Displaying the links

Currently when we instantiate (create) a room, we pass the room id to the creator. Now that room id also identifies the source room, so we can add the code to retrieve the links to the Room class.

The Link class

The links need somewhere to store them, and as the direction will be unique for each room, we will use a Dictionary.

The Link class will store the room id (source room id), where the link goes (destination id), the direction and the description of the link.

class Link():

    def __init__(self,sourceID,destinationID,direction,description):

        self.sourceID=sourceID

        self.destinationID=destinationID

        self.direction=direction

        self.description=description

    # Getters and Setters

    def get_sourceID(self):

        return self.sourceID

    def get_destinationID(self):

        return self.destinationID

    def get_direction(self):

        return self.direction

    def get_description(self):

        return self.description

Adding Links to the Room class

So the first modification is to the creator:

    def __init__(self,room_id,acursor):

        sql="SELECT * FROM rooms where roomID=%s "

        roomID=(str(room_id),)

        acursor.execute(sql,roomID)

        myresult = acursor.fetchall()

        for x in myresult:

            self.roomID=x[0]

            self.name=x[1]

            self.description=x[2]

        self.linked_rooms = {}

    # Add linked rooms

        sql="select destinationRoomID,direction,description from               links where sourceRoomID=%s"

        acursor.execute(sql,roomID)

        myresult = acursor.fetchall()

        for x in myresult:

            newLink=Link(self.roomID,x[0],x[1],x[2])

            self.linked_rooms[newLink.get_direction()]=newLink

The other modification is to extend the get_details method.
    def get_details(self):
        print(self.get_name())
        print("======")
        print(self.get_description())
        for direction in self.linked_rooms:
            link=self.linked_rooms[direction]
            print("There is " + link.get_description()+" to the "+direction)

Now additional changes will need to be made as we continue development, especially once we get to moving between rooms, and when this progresses to being a web application.

Testing the changes

Using the existing testroom.py code, you can examine the rooms by changing the room ID here:

   aroom=Room(1,mycursor)

   print(aroom.get_details())

Kitchen======A bright shiny IKEA kitchenThere is a plain door to the southNone>>>

   aroom=Room(2,mycursor)

   print(aroom.get_details())

Dining Hall======A room containing pale Scandinavian furnitureThere is a discrete door to the NorthThere is a grand door to the westNone>>>

   aroom=Room(3,mycursor)

   print(aroom.get_details())

Ballroom======A room whose floor is covered in brightly coloured balls.There is a grand door to the eastNone>>>

Next, moving between rooms.

References

https://www.w3schools.com/python/python_dictionaries.asp