JS - home inventory app code

Author: hobojoe1848

days/88-90-home-inventory-app/code/inventory.py

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+#!python3
+
+import sqlite3
+import sys
+from contextlib import contextmanager
+
+DB = "Inventory.db"
+
+#Script that creates the DB on first launch, otherwise is just a check.
+def first_launch():
+    try:
+        conn = sqlite3.connect(DB)
+    except:
+        sys.exit('Error code X')
+
+        
+#generator to yield a db cursor and close the connection nicely.
+@contextmanager
+def access_db():
+    try:
+        conn = sqlite3.connect(DB)
+        cursor = conn.cursor()
+        yield cursor
+    finally:
+        conn.commit()
+        conn.close()
+
+
+#A somewhat dirty menu. Improvement Point (make it a dict perhaps)
+def main_menu():
+    menu = {}
+    menu['1'] = "Add Room."
+    menu['2'] = "Add Inventory."
+    menu['3'] = "View Inventory List."
+    menu['4'] = "Total Value."
+    menu['5'] = "Exit."
+    while True:
+        print("\n")
+        for item, desc in sorted(menu.items()):
+            print(item, desc)
+
+        choice = input("Selection: ")
+        if choice == '1':
+            add_room()
+        elif choice == '2':
+            add_inventory(check_input())
+        elif choice == '3':
+            view_inventory(check_input())
+        elif choice == '4':
+            calc_total()
+        elif choice == '5':
+            sys.exit()
+        else:
+            print("Invalid option, try again.")
+
+
+#Adds a room. Scrubs the input first to only allow default chars.
+def add_room():
+    name = input("\nWhat name would you like to give the room? ")
+    name = scrub(name)
+    with access_db() as cursor:
+        cursor.execute("CREATE TABLE '" + name.lower() + "' """"
+                                    (Item TEXT, Value REAL)
+                                    """)
+        print("\nA room with name %s has been added to the db.\n" % name)
+
+
+#Parses the DB for table names and returns a list of the names.
+def list_rooms():
+    room_list = []
+    with access_db() as cursor:
+        cursor.execute("SELECT name FROM sqlite_master WHERE type='table'")
+        for room in cursor:
+            room_list.append(room[0])
+    return room_list
+
+
+#The scrubbing function. Removes all chars that aren't letters and numbers.
+def scrub(table_name):
+    return ''.join( chr for chr in table_name if chr.isalnum() )
+
+
+#Checks the users' input to see if it matches a room/table name.
+def check_input():
+    while True:
+        print('\n')
+        for room in list_rooms():
+            print(room)
+        selection = input('Select a room: ').lower()
+        if selection not in list_rooms():
+            print("\n%s does not exist." % selection)
+        else:
+            return scrub(selection)
+
+
+#Allows users to add an item and value to the DB of a specific room.
+def add_inventory(selection):
+    while True:
+        name = input("\nName of item: ")
+        cost = input("Monetary value: ")
+        with access_db() as cursor:
+            cursor.execute("INSERT INTO '" + selection + "' VALUES(?, ?)", [name, cost])
+
+        cont = input('\nHit Q to quit or any other key to continue: ')
+        if cont.lower() == 'q':
+            break
+
+
+#Returns a list of all items in a room and their total value.
+def view_inventory(selection):
+    total = 0
+    with access_db() as cursor:
+        cursor.execute("SELECT * FROM '" + selection + "'")
+        print("\n")
+        for data in cursor:
+            print("%s: $%d" % (data[0], data[1]))
+            total += data[1]
+        print("Total Value: $%d" % total)
+
+
+#Function to calculate the $ total of the entire database.
+def calc_total():
+    total = 0
+    room_list = list_rooms()
+    with access_db() as cursor:
+        for room in room_list:
+            cursor.execute("SELECT value FROM '" + room + "'")
+            for value in cursor:
+                total += value[0]
+    print("\nTotal Value of all rooms: $%d" % total)
+
+
+if __name__ == "__main__":
+    first_launch()
+    main_menu()