DEV Community: cienc

Github contribution workflow

cienc — Sun, 06 Feb 2022 08:01:08 +0000

1.Fork the repository

2.Clone the forked repository & Configure upstream

git clone FORKED-REPO
cd FORKED-REPO
git remote add upstream ORIGINAL-REPO
git remote -v

3.Configure environment for the project and install dependencies
Depending on the project, change sample.env to .env
If Node.js project, install packages by running npm install or yarn

4.Make a git branch & Make commits

git checkout -b BRANCH-NAME
git commit -m "KEYWORD #ISSUE-NUMBER - commit message"

5.Sync the repository & Push

git fetch upstream
git checkout master
git merge upstream/master
git checkout BRANCH-NAME
git rebase -i master
git push origin master
git push --set-upstream origin BRANCH-NAME

6.Make Pull Request
from BRANCH-NAME -> Original Repo's master

7.Remove the branch

git branch -d BRANCH-NAME
git push origin --delete BRANCH-NAME

[Javascript]

cienc — Sun, 09 May 2021 13:06:38 +0000

Setting up

Jest

npm install -g jest
npm root -g

# Run test
jest test.js --watch

debugger

function funcName() {
  //  
  debugger;
  //
}

node inspect test.js

# continue
debug> c

# enter repl to check the variables
debug> repl

Null vs Undefined

let test;
console.log( test ); // undefined

test = null
console.log( test ); // null

console.log( 1 + null ); // 1
console.log( 1 + undefined ); // NaN

console.log( null == undefined ); // true
console.log( null === undefined ); // false

Reverse String

function reverse(str) {
}

Memoization - Fibonacci

function memoize(fn) {
  const cache = {};
  return function (...args) {
    if (cache[args]) {
      return cache[args];
    }

    const result = fn.apply(this, args);
    cache[args] = result;

    return result;
  };
}

function slowFib(n) {
  if (n <= 1) return n;

  return fib(n - 1) + fib(n - 2);
}

const fib = memoize(slowFib);

[Python] Django 101

cienc — Sun, 09 May 2021 11:09:54 +0000

Install

python3 -m venv ./venv
source ./venv/bin/activate

# Escape from venv
deactivate

# Check packages installed in the venv
pip freeze

# Create project & app
pip install django
django-admin startproject PROJECT-NAME
python manage.py start app APP-NAME

Commands

# Run server
python manage.py runserver

# Create migrations
python manage.py makemigrations

# Run migration
python manage.py migrate

# Collect static files
python manage.py collectstatic

Postgres DB setup

sudo -u postgres psql

postgres=# CREATE DATABASE myproject;
postgres=# CREATE USER myprojectuser WITH PASSWORD 'password';