# File Name: app.py # Modified Date: March 24, 2017 # Description: This python file contains database configuration and creates database tables and fields using flask_sqlalchemy. # Users' values passed from Javascript are inserted into the database table. # It also has mapping request to interact with specific html files and # it reads a file of itemlist.text and prints out to the console. __author__ = "Inyoung Choung" import tkinter from tkinter import messagebox from flask_sqlalchemy import SQLAlchemy from flask import Flask, render_template, request # passing the whole app code to Flask app = Flask(__name__) # Configuration for Database ORM - database name: grocery app, user: groceryadmin, password: VKov2q3XTtqj6w9o app.config['SQLALCHEMY_DATABASE_URI'] = 'postgresql://groceryadmin:VKov2q3XTtqj6w9o@localhost/groceryapp' app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = True # Database instantiation db = SQLAlchemy(app) # database ORM calc table - 3 columns class Calc(db.Model): __tablename__="calc" # database fields id = db.Column(db.Integer, primary_key=True) result = db.Column(db.String(64)) timestampe = db.Column(db.TIMESTAMP) # adding constraints to delete all data in Item when calc is deleted. item = db.relationship('Item', backref='calc', cascade='all, delete-orphan', lazy='dynamic') # database ORM item table - 9 columns class Item(db.Model): __tablename__ = "items" # database fields id = db.Column(db.Integer, primary_key=True) item_type = db.Column(db.String(64)) brand_name = db.Column(db.String(64)) price = db.Column(db.DECIMAL) weight = db.Column(db.DECIMAL) weight_type = db.Column(db.String(5)) discount = db.Column(db.DECIMAL) discount_type = db.Column(db.String(20)) calc_id = db.Column(db.Integer, db.ForeignKey(Calc.id)) # create all the tables defined as classes # db.create_all() # mapping request to URLs @app.route('/', methods = ['GET', 'POST']) def index(): if request.method == 'GET': # renders to html file return render_template('index.html') def convert(weightT1, weightT2, weight2): if weightT1 == "lb": if weightT2 == "kg": weight2 = float(weight2) * 2.20462 elif weightT2 == "g": weight2 = float(weight2) * 0.002205 elif weightT1 == "kg": if weightT2 == "lb": weight2 = float(weight2) * 0.453592 elif weightT2 == "g": weight2 = float(weight2) * 0.001 elif weightT1 == "g": if weightT2 == "kg": weight2 = float(weight2) * 1000 elif weightT2 == "lb": weight2 = float(weight2) * 453.592 return weight2 def alert_message(message_arg): if message_arg is None: message = str("Please fill out all the forms.") else: message = message_arg return message global newWeightForSecondItem # end point where python gets user data from javascript @app.route('/calculate', methods = ['GET']) def calculate(): # get value from html itemtype = (request.args.get('param1')) brandN1 = (request.args.get('param2')) brandN2 = (request.args.get('param3')) price1 = (request.args.get('param4')) price2 = (request.args.get('param5')) weight1 = (request.args.get('param6')) weightT1 = (request.args.get('param7')) weight2 = (request.args.get('param8')) weightT2 = (request.args.get('param9')) discount1 = (request.args.get('param10')) discountT1 = (request.args.get('param11')) discount2 = (request.args.get('param12')) discountT2 = (request.args.get('param13')) if (itemtype is None or itemtype == "" or brandN1 is None or brandN1 == "" or brandN2 is None or brandN2 == "" or price1 is None or price1 == "" or price2 is None or price2 == "" or weight1 is None or weight1 == "" or weightT1 is None or weightT1 == "" or weight2 is None or weight2 == "" or weightT2 is None or weightT2 == "" or discount1 is None or discount1 == "" or discountT1 is None or discountT1 == "" or discount2 is None or discount2 == "" or discountT2 is None or discountT2 == ""): # hide main window root = tkinter.Tk() root.withdraw() messagebox.showerror( "Alert - Empty fields", alert_message("Please fill out all the forms.")) # after users values are accepted, do calculation. if weightT1 != weightT2: newWeightForSecondItem = convert(weightT1, weightT2, weight2) # both items have the same weight type from this point else: newWeightForSecondItem = weight2 if discountT1 == "percentage": finalPrice1 = float((float(price1) - (float(price1) * (float(discount1) * float(0.01)))) / float(weight1)) elif discountT1 == "dollar": finalPrice1 = float((float(price1) - float(discount1)) / float(weight1)) if discountT2 == "percentage": finalPrice2 = float((float(price2) - (float(price2) * (float(discount2) * float(0.01)))) / float(newWeightForSecondItem)) elif discountT2 == "dollar": finalPrice2 = float((float(price2) - (float(discount2))) / float(newWeightForSecondItem)) if finalPrice1 > finalPrice2: priceDiff = round(float(finalPrice1 - finalPrice2), 3) print(brandN1 + str(" is cheaper by "), priceDiff) result = str(brandN1 + str(" is cheaper by ") + str(priceDiff) + str(" cents per unit weight ")) elif finalPrice1 < finalPrice2: priceDiff = round(float(finalPrice2 - finalPrice1), 3) print(brandN2 + str(" is cheaper by "), priceDiff) result = str(brandN2 + str(" is cheaper by ") + str(priceDiff) + str(" cents per unit weight ")) else: result = str("The price is equal so get anything!") # hide main window root = tkinter.Tk() root.withdraw() messagebox.showinfo("Calculation Result", result) try: # define array variables to be ready to match with db columns brand_names = [brandN1, brandN2] prices = [price1, price2] weights = [weight1, weight2] weight_types = [weightT1, weightT2] discounts = [discount1, discount2] discount_types = [discountT1, discountT2] # iteration variable for loop i = 0 # loop twice to save two compared items into database for i in range(0, 2): item = Item(item_type = itemtype, brand_name = brand_names[i], price =prices[i], weight=weights[i] , weight_type = weight_types[i], discount = discounts[i] , discount_type = discount_types[i]) # insert a new row into the database db.session.add(item) # write it to db disk once the loop is done db.session.commit() return result # catch the exception and print it except ValueError: print(ValueError) print("failed to create new row") return -1 # File I/O - prints a list of grocery items def writefile(path, word): # open a file for writing and create it if it doesn't exist. if path is None: # set a specific path filepath = "C:\In-young Choung\Computer Programming\Self Programming Files\grocerycalc\itemlist.txt" # output a file if it doesn't exist f = open(filepath, "w+") # write some texts inside the opened file f.write("chicken, ") f.write("milk") readfile(filepath) else: # when the path is specified filepath= path # output a file if it doesn't exist f = open(filepath, "w+") # write text that is passed as a paramter in the method f.write(word) # read file that is created and pass filepath as a parameter def readfile(filepath): # open the file in the defined path and "r" read it f = open(filepath, "r") if f.mode == 'r': # use read function to read the entire file. contents = f.read() #print the file content in the console print(contents) # main method if __name__ == '__main__': app.debug = True # app.debug = False writefile(None, None) app.run()