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Step 3 - "List" option |
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In this project, one menu items's information is a dictionary object that is guaranteed to have the following keys:
"name": a string with the menu item's name."calories": an integer with the number of calories in the menu item."price": a float with the menu item's price using the format 00.00."is_vegetarian": a string with value "yes" or "no" for if the menu item is vegetarian."spicy_level": an integer from 1 to 4, representing the menu item's spice level.
Here is an example of what a dictionary with a single menu item's information could look like:
{
"name": "burrito",
"calories": 500,
"price": 12.90,
"is_vegetarian": "yes",
"spicy_level": 2
}In this project, for the ease of testing, we will hard-code a list of menu item information at the top of the main program, after the dictionary the_menu. We will refer to it as restaurant_menu_list. Below is just an example list containing the menu item information dictionaries that can be used to test our system as we develop it. We encourage you to add more of your own examples as long as they adhere to the correct formats and types of the dictionary values.
restaurant_menu_list = [
{
"name": "burrito",
"calories": 500,
"price": 12.90,
"is_vegetarian": "yes",
"spicy_level": 2
},
{
"name": "rice bowl",
"calories": 400,
"price": 14.90,
"is_vegetarian": "no",
"spicy_level": 3
},
{
"name": "margherita",
"calories": 800,
"price": 18.90,
"is_vegetarian": "no",
"spicy_level": 2
}
]First, create a variable restaurant_menu_list to hold the list of menu items (stored as as list of dictionaries, as shown above) at the top of your main program. We will refer to it as restaurant_menu_list.
Additionally, you need to add two more variables to your main program:
list_menuwill contain the "List" menu sub-optionsspicy_scale_mapwill contain the mapping of the spicy_level values, as integers, to a string for the name of the spice level
list_menu = {
"A": "complete menu",
"V": "vegetarian dishes only",
}
spicy_scale_map = {
1: "Not spicy",
2: "Low key spicy",
3: "Hot",
4: "Diabolical",
}Next, add the following code to your main program to implement the listing of the menu items - you do not need to change it.
Note that there are new functions list_helper(), get_selection() that are also given to you after the code below.
elif opt == 'L':
list_helper(list_menu, restaurant_menu_list, spicy_scale_map)In your functions.py, copy the list_helper and get_selection() functions given below - you will use these functions as-is. These functions are central to many of the menu options this program can perform. We have an option in the function parameters (go_back) that can be used if the user changes their mind and wants to return to the main menu.
def list_helper(list_menu, restaurant_menu_list, spicy_scale_map):
if len(restaurant_menu_list) == 0:
print("WARNING: There is nothing to display!")
# Pause before going back to the main menu
input("::: Press Enter to continue")
else:
subopt = get_selection("List", list_menu)
if subopt == 'A':
print_restaurant_menu(restaurant_menu_list, spicy_scale_map, show_idx=True, start_idx=1)
elif subopt == 'V':
print_restaurant_menu(restaurant_menu_list, spicy_scale_map, show_idx=True, start_idx=1, vegetarian_only=True)
######## LIST OPTION ########
def get_selection(action, suboptions, to_upper=True, go_back=False):
"""
param: action (string) - the action that the user
would like to perform; printed as part of
the function prompt
param: suboptions (dictionary) - contains suboptions
that are listed underneath the function prompt.
param: to_upper (Boolean) - by default, set to True, so
the user selection is converted to upper-case.
If set to False, then the user input is used
as-is.
param: go_back (Boolean) - by default, set to False.
If set to True, then allows the user to select the
option M to return back to the main menu
The function displays a submenu for the user to choose from.
Asks the user to select an option using the input() function.
Re-prints the submenu if an invalid option is given.
Prints the confirmation of the selection by retrieving the
description of the option from the suboptions dictionary.
returns: the option selection (by default, an upper-case string).
The selection be a valid key in the suboptions
or a letter M, if go_back is True.
"""
selection = None
if go_back:
if 'm' in suboptions or 'M' in suboptions:
print("Invalid submenu, which contains M as a key.")
return None
while selection not in suboptions:
print(f"::: What field would you like to {action.lower()}?")
for key in suboptions:
print(f"{key} - {suboptions[key]}")
if go_back:
selection = input(f"::: Enter your selection "
f"or press 'm' to return to the main menu\n> ")
else:
selection = input("::: Enter your selection\n> ")
if to_upper:
selection = selection.upper() # to allow us to input lower- or upper-case letters
if go_back and selection.upper() == 'M':
return 'M'
print(f"You selected |{selection}| to",
f"{action.lower()} |{suboptions[selection]}|.")
return selectionThe function print_restaurant_menu() will list all or some of the menu items stored in the restaurant_menu_list.
Use the implementation from LAB 7.19.
def print_restaurant_menu(restaurant_menu, spicy_scale_map, name_only=False, show_idx=True, start_idx=0, vegetarian_only=False):
"""
param: restaurant_menu (list) - a list object that holds the dictionaries for each dish
param: spicy_scale_map (dict) - a dictionary object that is expected
to have the integer keys that correspond to the "level of spiciness."
param: name_only (Boolean)
If False, then only the name of the dish is printed.
Otherwise, displays the formatted dish information.
param: show_idx (Boolean)
If False, then the index of the menu is not displayed.
Otherwise, displays the "{idx + start_idx}." before the
dish name, where idx is the 0-based index in the list.
param: start_idx (int)
an expected starting value for idx that
gets displayed for the first dish, if show_idx is True.
param: vegetarian_only (Boolean)
If set to False, prints all dishes, regardless of their
is_vegetarian status ("yes/no" field status).
If set to True , display only the dishes with
"is_vegetarian" status set to "yes".
returns: None; only prints the restaurant menu
"""
# Go through the dishes in the restaurant menu:
for ...:
# if vegetarian_only is True and the dish is not vegetarian, skip
if vegetarian_only and ...:
.....
# if the index of the task needs to be displayed (show_idx is True), print dish index only
if show_idx == True:
print(.....)
# print the name of the dish
# if name_only is False
if not name_only:
print(.....)
print(.....)
print(.....)
print(.....)
"""Make sure that the vegetarian_only field correctly displays either all menu items (setting is False - the default) or only menu items that are vegetarian (setting is True), depending on what was selected by the user in the main program.
If none of the menu items are marked as vegetarian, then nothing is printed.
-
Assuming the restaurant menu list that's hard-coded above, below is a sample program output for listing
complete menu.========================== What would you like to do? L - List A - Add U - Update D - Delete H - Display restaurant expense rating S - Save the data to file R - Restore data from file Q - Quit this program ========================== ::: Enter a menu option > L You selected option L to > List. ::: What field would you like to list? A - complete menu V - vegetarian dishes only ::: Enter your selection > A You selected |A| to list |complete menu|. ------------------------------------------ 1. BURRITO * Calories: 500 * Price: 12.9 * Is it vegetarian: yes * Spicy level: Low key spicy 2. RICE BOWL * Calories: 400 * Price: 14.9 * Is it vegetarian: no * Spicy level: Hot 3. MARGHERITA * Calories: 800 * Price: 18.9 * Is it vegetarian: no * Spicy level: Low key spicy ------------------------------------------ ::: Press Enter to continue -
Below is another sample program output for listing V (vegetarian menu items only).
You selected |V| to list |vegetarian dishes only|. ------------------------------------------ 1. BURRITO * Calories: 500 * Price: 12.9 * Is it vegetarian: yes * Spicy level: Low key spicy ------------------------------------------ ::: Press Enter to continue
If you submit to Checkpoint 1 on Gradescope after finishing the work in this Step ({{page.title}}), you should be able to pass at least these tests:
Once you pass at least these, you are ready to move to the next step.