Coding Style

I. Coding Style

1. Name

Using camelCase for variable, function, object eg: name, idUser, idCallcenter
Using PascalCase for class, component eg: User, Callcenter
Using UPPER_CASE for constant eg: MAX, MIN
Using snake_case for file name eg: user.service.ts
Using kebab-case for folder name eg: user-service

2. Variable

Using let, const instead of var eg: let name = 'Gcalls'; const age = 2023 - 2015
Using const for variables that do not change eg: const name = 'Gcalls';
Using let for variable that change eg: let age = 2023 - 2015; age = 2023 - 2017;

3. Function

Using arrow function instead of function declaration

Example:

const fn1 = (a) => {
  return a * a;
};

instead of

function fn1(a) {
  return a * a;
}

Using function expression for function that use in one file

Example:

const fn1 = function (a) {
  return a * a;
};

instead of

function fn1(a) {
  return a * a;
}

4. Object

Using an object literal instead of js new Object()
- Example:
```
const obj = {};
```
instead of
```
const obj = new Object();
```

Using spread operator instead of Object.assign()

Example:

const obj1 = { a: 1, b: 2 };
const obj2 = { c: 3, d: 4 };
const obj3 = { ...obj1, ...obj2 }; // { a: 1, b: 2, c: 3, d: 4 }

Using rest operator instead of Object.keys()

Example:

const obj = { a: 1, b: 2, c: 3 };
const { a, ...rest } = obj; // a = 1, rest = { b: 2, c: 3 }

Using object destructuring instead of obj.a, obj.b

Example:

const obj = { a: 1, b: 2, c: 3 };
const { a, b, c } = obj; // a = 1, b = 2, c = 3

5. Array

Using array literal instead of new Array()
- Example:
```
const arr = [];
```
instead of
```
const arr = new Array();
```

Using spread and rest operator instead of push, concat, unshift, splice, slice

Example:

const arr1 = [1, 2, 3];
const arr2 = [4, 5, 6];
const arr3 = [...arr1, ...arr2]; // [1, 2, 3, 4, 5, 6]
const arr4 = [...arr1, 7, 8, 9]; // [1, 2, 3, 7, 8, 9]
const [a, b, ...rest] = arr1; // a = 1, b = 2, rest = [3]

6. String

Using template string instead of string concatenation

Example:

const name = "Gcalls";
const str1 = `Hello ${name}`; // Hello Gcalls
const str2 = `Hello ${name.toUpperCase()}`; // Hello GCALLS

7. Comparison

Using === instead of ==

Example:

const a = 1;
const b = "1";
a === b; // false
a == b; // true

Using !== instead of !=

Example:

const a = 1;
const b = "1";
a !== b; // true
a != b; // false

Using >, <, >=, <= instead of >=, <=, ==, !=

Example:

const a = 1;
const b = 2;
a > b; // false
a < b; // true
a >= b; // false
a <= b; // true

Using &&, || instead of &, |

Example:

const a = 1;
const b = 2;
const c = 3;
a > b && a > c; // false
a > b || a > c; // false

8. Loop

Using for...of instead of for...in

Example:

const arr = [1, 2, 3];
for (const item of arr) {
  console.log(item);
}

Using methods instead of a self-handler function

Example:

const arr = [1, 2, 3];
arr.forEach((item) => {
  console.log(item);
});

instead of

const arr = [1, 2, 3];
for (let i = 0; i < arr.length; i++) {
  console.log(arr[i]);
}

9. Module

Using ES6 module instead of CommonJS

Example:

// file1.js
export const name = "Gcalls";
export const age = 2023 - 2015;
export default function (a) {
  return a * a;
}

// file2.js
import fn1, { name, age } from "./file1.js";

10. Others

10.1. Formatter

Using Prettier for code formatter
Using ESLint for code linter
Using Husky for pre-commit hook
Using lint-staged for linting before commit
Using commitizen for commit message convention

10.2. Logging

Using Turbo Console Log for logging
Using Sentry for error tracking

II. How to update code

For small changes ( 1 2 lines of code)
- Can edit directly, comment right next to it or comment all, write new code
For medium changes ( 1 block of code in a function, write a new function)
- Comment on old code, write new code below, write a new comment to explain the old code and the new code, comment end of the new code block
```
//fix limit
//limit = parseInt(limit)
```
To add a file or folder
- Create a file or folder, and comment reason for creating the file or folder
To delete a file or folder
- Comment the reason for deleting the file or folder
For update README.md
- Comment the reason for updating README.md
For update changes if already comment before
- Comment on the reason for updating the change

III. Regulation of API

1. Success

{
  "success": true,
  "data": {
    "id": 1,
    "name": "Gcalls",
    "age": 6
  }
}

2. Error

For errors with user authentication, using HTTP status code 403 eg: the user does not permission
For errors with authentication, using HTTP status code 401 eg: token invalid, token expired
For resource not found error, use HTTP status code 404
For server errors, use HTTP status code 500
For validation error, use HTTP status code 422

For all error responses, use HTTP status code 400

{
  "success": false,
  "errors": [
    {
      "field": "name",
      "message": "Name is required"
    },
    {
      "field": "age",
      "message": "Age must be a number"
    }
  ]
}

IV. Regulation of structure

1. Folder structure

src
├──models => It\'s a part that communicate with database, like query, create, update, delete
├──configs => Contains a service config, get from `.env` file
├──routers => Contains files for handle routing. Each file is a router
├──controllers => Contains files for handle request, response
├──middlewares => Contains files for handle middleware
└──utils => Contains utility or helper functions that provide common functionality or reusable eg: formatDate, formatNumber
index.js => For start project

V. Version Control

1. Common rules

1.1. Branch naming rule

The branch name must be formatted as follows: [dev|doc|fix]_<PoC>_<title>

1.2. Commit rule

Short commit message, commit message must be written in English
Commit messages must follow the conventions
- feat: A new feature
- fix: A bug fix
- docs: Documentation only changes
- style: Changes that do not affect the meaning of the code (white-space, formatting, missing semi-colons, etc)
- refactor: A code change that neither fixes a bug nor adds a feature
- perf: A code change that improves performance
- test: Adding missing or correcting existing tests
- chore: Changes to the build process or auxiliary tools and libraries such as documentation generation
- build: Changes that affect the build system or external dependencies (example scopes: gulp, broccoli, npm)
- ci: Changes to our CI configuration files and scripts (example scopes: Travis, Circle, BrowserStack, SauceLabs)
- revert: Reverts a previous commit
- wip: Work in progress

1.3. Changelog rule

This guide following Keep a Changelog

Changelog must be written in English
Keep an unreleased section at the top to track upcoming changes.

Example changelog

## [1.0.0] - 2020-01-01

### Added

- Add new feature

### Changed

- Change feature

### Fixed

- Fix bug

VI. Flow handling ticket

Flow handling ticket

I. Coding Style​

1. Name​

2. Variable​

3. Function​

4. Object​

5. Array​

6. String​

7. Comparison​

8. Loop​

9. Module​

10. Others​

10.1. Formatter​

10.2. Logging​

II. How to update code​

III. Regulation of API​

1. Success​

2. Error​

IV. Regulation of structure​

1. Folder structure​

V. Version Control​

1. Common rules​

1.1. Branch naming rule​

1.2. Commit rule​

1.3. Changelog rule​

VI. Flow handling ticket​

I. Coding Style

1. Name

2. Variable

3. Function

4. Object

5. Array

6. String

7. Comparison

8. Loop

9. Module

10. Others

10.1. Formatter

10.2. Logging

II. How to update code

III. Regulation of API

1. Success

2. Error

IV. Regulation of structure

1. Folder structure

V. Version Control

1. Common rules

1.1. Branch naming rule

1.2. Commit rule

1.3. Changelog rule

VI. Flow handling ticket