feat: add util to obtain b64 header from user/pass

Author: ricveal

README.md

@@ -16,25 +16,29 @@
 
 ## The problem
 
-I'm usually repeating a section of code for extract credentials (username and password) given an authorization header.
-This utility wants to extract this logic to reuse it across my different projects.
+I'm usually repeating code when I was working with Basic Authentication. This
+type of authentication uses Base64 encoding so it's very usual to extract
+credentials (username and password) given an authorization header or, given the
+credentials, build the header. This utility wants to extract this logic to reuse
+it across my different projects.
 
 ## This solution
 
-It's a simple utility function which, process your request headers and return an object with the username and the password or an Error if:
+It's a simple set of utility functions that:
 
-- The authorization (or Authorization) header is not given.
-- Its format is not correct.
+- process your request headers and return an object with the username and the
+  password or an Error if:
 
+  - The authorization (or Authorization) header is not given.
+  - Its format is not correct.
+
+- given a username and password, returns a Basic header.
 
 ## Table of Contents
 
 <!-- START doctoc generated TOC please keep comment here to allow auto update -->
 <!-- DON'T EDIT THIS SECTION, INSTEAD RE-RUN doctoc TO UPDATE -->
 
-- [The problem](#the-problem)
-- [This solution](#this-solution)
-- [Table of Contents](#table-of-contents)
 - [Installation](#installation)
 - [Usage](#usage)
 - [Other Solutions](#other-solutions)
@@ -57,12 +61,22 @@ npm install --save @ricveal/basic-auth-utils
 
 ## Usage
 
-Once it's installed as dependency, you only have to import it and use it with a `headers` object:
+Once it's installed as dependency, you only have to import it and use the util
+you prefer:
+
+```ts
+import {
+  getUsernameAndPasswordFromAuthBasic,
+  getAuthBasicFromUsernameAndPassword,
+} from '@ricveal/basic-auth-utils'
+
+const headers = {
+  authorization: 'Basic dXNlcjp0ZXN0',
+}
+const {username, password} = getUsernameAndPasswordFromAuthBasic(headers)
+console.log(username, password) // 'user', 'test'
 
-```js
-const headers = { authorization: 'Basic dXNlcjp0ZXN0' }
-const credentials = getUsernameAndPasswordFromAuthBasic(headers)
-// credentials = { username: "user", password: "test" }
+console.log(getAuthBasicFromUsernameAndPassword('user', 'test')) // 'Basic dXNlcjp0ZXN0'
 ```
 
 ## Other Solutions

src/__tests__/index.ts

@@ -1,44 +1,65 @@
-import { getUsernameAndPasswordFromAuthBasic } from "../index";
+import {
+  getAuthBasicFromUsernameAndPassword,
+  getUsernameAndPasswordFromAuthBasic,
+} from '../index'
 
 describe('Get Username and Password From Headers', () => {
   it('should throw an error when headers input objet is empty', () => {
     const headers = {}
     const t = () => {
       getUsernameAndPasswordFromAuthBasic(headers)
-    };
-    expect(t).toThrowError('Invalid or Missing Authorization header');
-  });
+    }
+    expect(t).toThrowError('Invalid or Missing Authorization header')
+  })
   it('should throw an error when headers input objet has not "authorization" or "Authorization" entries', () => {
-    const headers = { "test": "value" }
+    const headers = {test: 'value'}
     const t = () => {
       getUsernameAndPasswordFromAuthBasic(headers)
-    };
-    expect(t).toThrowError();
-  });
+    }
+    expect(t).toThrowError()
+  })
   it('should throw an error when authorization header has not start with "Basic "', () => {
-    const headers = { authorization: 'test value' }
+    const headers = {authorization: 'test value'}
     const t = () => {
       getUsernameAndPasswordFromAuthBasic(headers)
-    };
-    expect(t).toThrowError();
-  });
+    }
+    expect(t).toThrowError()
+  })
   it('should throw an error when Authorization header has not start with "Basic "', () => {
-    const headers = { Authorization: 'test value' }
+    const headers = {Authorization: 'test value'}
     const t = () => {
       getUsernameAndPasswordFromAuthBasic(headers)
-    };
-    expect(t).toThrowError();
-  });
+    }
+    expect(t).toThrowError()
+  })
   it('should return username and password when authorization header is properly set', () => {
-    const headers = { authorization: 'Basic dXNlcjp0ZXN0' }
-    expect(getUsernameAndPasswordFromAuthBasic(headers)).toEqual({username: "user", password: "test"})
-  });
+    const headers = {authorization: 'Basic dXNlcjp0ZXN0'}
+    expect(getUsernameAndPasswordFromAuthBasic(headers)).toEqual({
+      username: 'user',
+      password: 'test',
+    })
+  })
   it('should return username and password when Authorization header is properly set', () => {
-    const headers = { Authorization: 'Basic dXNlcjp0ZXN0' }
-    expect(getUsernameAndPasswordFromAuthBasic(headers)).toEqual({username: "user", password: "test"})
-  });
+    const headers = {Authorization: 'Basic dXNlcjp0ZXN0'}
+    expect(getUsernameAndPasswordFromAuthBasic(headers)).toEqual({
+      username: 'user',
+      password: 'test',
+    })
+  })
   it('should return username and password when both authorization Authorization header is properly set', () => {
-    const headers = { authorization: 'Basic dXNlcjp0ZXN0', Authorization: 'Basic dXNlcjp0ZXN0' }
-    expect(getUsernameAndPasswordFromAuthBasic(headers)).toEqual({username: "user", password: "test"})
-  });
-});
+    const headers = {
+      authorization: 'Basic dXNlcjp0ZXN0',
+      Authorization: 'Basic dXNlcjp0ZXN0',
+    }
+    expect(getUsernameAndPasswordFromAuthBasic(headers)).toEqual({
+      username: 'user',
+      password: 'test',
+    })
+  })
+})
+
+describe('should return b64 string from username and password', () => {
+  expect(getAuthBasicFromUsernameAndPassword('user', 'test')).toEqual(
+    'Basic dXNlcjp0ZXN0',
+  )
+})

src/index.ts

@@ -5,11 +5,8 @@ interface Headers {
 }
 
 export const getUsernameAndPasswordFromAuthBasic = (headers: Headers) => {
-  const authHeader = headers.authorization ?? headers.Authorization;
-  if (
-    !authHeader ||
-    !authHeader.includes('Basic ')
-  ) {
+  const authHeader = headers.authorization ?? headers.Authorization
+  if (!authHeader || !authHeader.includes('Basic ')) {
     throw new Error('Invalid or Missing Authorization header')
   }
 
@@ -19,3 +16,11 @@ export const getUsernameAndPasswordFromAuthBasic = (headers: Headers) => {
   const [username, password] = credentials.split(':')
   return {username, password}
 }
+
+export const getAuthBasicFromUsernameAndPassword = (
+  username: string,
+  password: string,
+) => {
+  const encode = Buffer.from(`${username}:${password}`).toString('base64')
+  return `Basic ${encode}`
+}