FormData from Form in mutation!

GenIl — Fri, 27 Jan 2023 09:29:11 +0000

I have a form in React App and use React Query for mutation data in this array of posts:

const POSTS = [
  { id: 1, title: "Green Olly", author: "Garry Molland" },
  { id: 2, title: "Fargus the Greatest", author: "Mazzy Fazzy" },
];

I want to send new post information from the HTML form with the new title and author.

<form >
        <div className="block">
          <label htmlFor="title">Title</label>
          <input name="title" id="title" type="text"></input>
        </div>
        <div className="block">
          <label htmlFor="author">Author</label>
          <input name="author" id="author" type="text"></input>
        </div>
        <button type="submit" >AddNew</button>
      </form>

1.Add onSubmit handler for Form

 <form onSubmit={(e)=> {
        e.preventDefault();
        newPostMutation.mutate(new FormData(e.target));
        }}>

We create new FormData object with From data and prevent Form's standard "action".

2.In our newPostMutation we use useMutation hook because of mutation of the original array of Posts.

const newPostMutation = useMutation({
    mutationKey: ["addNewPost"],
// key - a unique name for this particular mutation
    mutationFn: async (postFromForm) => {
      const newPost = Object.fromEntries(postFromForm);
      return await wait(1000).then(()=> POSTS.push({id: crypto.randomUUID(), title: newPost.title, author: newPost.author}))},
      onSuccess: () => {
        qClient.invalidateQueries(["posts"]);
      }
  })

postFromForm parameter in async gets new FormData(e.target), then we use Object.fromEntries()transforms a list of key-value pairs into an object. Then we use newPost object to add its properties to pushing object to the Posts array.

wait(1000) function for simulation API work

Mortgage Calculator Python

GenIl — Thu, 08 Apr 2021 15:06:04 +0000

I've done this portfolio project in Computer Science course CodeAcademy

Project Objectives:

Build a terminal program using Python
Add at least one interactive feature using input()
Use Git version control
Use the command line and file navigation
Write a technical blog post on the project

I've chosen to build Mortgage Calculator. It's not so fun but pretty useful.

Functionality of the terminal program

Take user's input:

Duration of loan programm
Loan Amount
Interest Rate per year

Mortgage calculation Implementation

Output:

Total Monthly Payment
Total Interest Paid
Total of n-months Payments
Show monthly amortization table.

Work on the project consists of three parts:

Project Brainstorming
Exploring subject area
Program implementation

The project have been implemented in two versions. With python packages and without it.

In the first version I use numpy_financial 1.0.0 package. It contains a collection of elementary financial functions. In particular pmt() function that computes the payment against loan principal plus interest (a monthly mortgage payment). As well as ipmt() and ppmt(). The interest portion of monthly payment and the payment against loan principal. This two functions return an array of Interest/principal portion of payment for every month.

The total payment is made up of payment against principal plus interest.

pmt = ppmt + ipmt

The second version uses mortgage formula for calculating monthly payment.

Code consists three parts:

Variables-Input part
Functions part
Output part

In Functions part we have paidEveryMonth(interestRate, months, borrowed):

def paidEveryMonth(interestRate, months, borrowed):             #fixed monthly payment
    return (borrowed * true_rate * ((true_rate + 1)**months)) / ((true_rate + 1)**months - 1)#Mortgage formula

There is the logic of the Mortgage function:

def fullReport(total_pem, borrowed) function forms monthly amortization table.

def fullReport(total_pem, borrowed):
    print("||||||||||||||||||||||||||||||||||||||||")
    print("MONTH -> P&I   " + "= PRINCIPAL + INTEREST| PRINCIPAL REMAINING")
    fmt = '{0:2d} -> {4:8.2f} = {1:8.2f} + {2:8.2f} | {3:8.2f}' # Format our table
    for index in range(1, months + 1):                          #for every month
        interest = borrowed * interestRate / 12                 #interest to the end of the month
        principal = total_pem - interest                        #principal repayment
        borrowed -= principal                                   #balance      
        print(fmt.format(index, principal, interest, borrowed, total_pem))

A link to my code on GitHub.

Forem: GenIl

FormData from Form in mutation!

Mortgage Calculator Python

Project Objectives:

Functionality of the terminal program

Work on the project consists of three parts: