ShoppingList-BE

This is the backend of my ShoppingList project.

Getting started

In order to run docker containers, you obviously need to install docker and optionally docker-compose.

The shopping list has to be run in two separate docker containers:

• shoppinglist-ui (frontend)
• shoppinglist-be (backend)

I suggest using docker-compose to run them in a stack:

#docker-compose.yml
version: "3.9"

volumes:
  backend_data:

services:
  frontend:
    image: ghcr.io/syntoxr/shoppinglist-fe:latest
    restart: always
    container_name: shoppinglist-frontend
    ports:
      - 80:80
    hostname: shoppinglist-ui
    environment:
      - API_HOST= http://shoppinglist-be:8080

  backend:
    image: ghcr.io/syntoxr/shoppinglist-be:latest
    restart: always
    container_name: shoppinglist-backend
    expose:
      - 8080
    hostname: shoppinglist-be
    volumes:
      - backend_data:/usr/local/server/data
    environment:
      - 'USERS=[{"name": "user", "password": "notSave"}]'
      - TOKEN_SECRET=RaNdOm-StRiNg
      - TOKEN_LIFETIME=3600

can also be seen here

Environment variables

Key	Default value	Description
USERS	[ ]	JSON array which contains all users that schould be albe to login. If not provided no one will be able to login.
TOKEN_SECRET	?	Secret which the JWTs should be signed with. If left empty, a new one will be generated at each startup. When changed all clients have to login again. The longer the secret the better.
TOKEN_LIFETIME	3600	Number in seconds new tokens should be valid. Clients with expired tokens obviously can't acces resources anymore.
LOGIN_RATE_LIMT	5	Allowed number of login requests per minute.
RESOURCE_RATE_LIMT	50	Allowed number of resource requests per minute.

API

General API endpoint: /api/

Websocket

The Frontend uses socket.io in order to communicate with the backend, wich is reachable under /api/socket.

The following rooms are being used (from a client perspective):

Name	Sending	Acknowledgement	Description	Recieving	Description
ADD_ITEM	{item: Item}	{code: number, body: {oldId: number, newId: number} | string}	JSON object containing the Item that should be added. Returns object containing code and body. Body can contain item ids or an error string	{item: Item}	JSON object containing the Item that was added from some other client. This is being send to all clients except the one that send ADD_ITEM.
GET_ITEMS	{}	{code: number, body: Item[] | string}	Just an empty object in order to request items. Returns object containing code and body. Body can contain item array or an error string	-	-
UPDATE_ITEM	{item: Item}		JSON object containing the Item that should be updated	{item: Item}	JSON object containing the Item that was updated from some other client. This is being send to all clients except the one that send UPDATE_ITEM.
DELETE_ITEM	{id: number}		JSON object containing the id of an item that should be deleted	{id: number}	JSON object containing the id of an item that was deleted from some other client. This is being send to all clients except the one that send DELETE_ITEM.

REST

The Rest endpoint can be used to easily interact with the backend through other services.

The REST endpoints are served under /api/

Name	Endpoint	Reguest type	Consumed data	Response data	Description
authenticate	/auth/api/login/	GET	-	{token: JWT}	Requires basic auth cretentials as a Bearer Token authorization header. Responds with a JSON web token.
add item	/shoppinglist/item/	POST	Item	{ oldId: number, newId: number }	Consumes an item with a temporary id and updates backend. Responds with the old- and new id
get items	/shoppinglist/items/	GET	-	Item	Returns complete list of items in an array of items
update item	/shoppinglist/item/{id}/	PATCH	Item	-	Consumes an item and updates backend accordingly
delete item	/shoppinglist/item/{id}/	DELETE	-	-	Deletes item on backend

Item

The item list is a list of all entered items, regardless of whether they were checked or not. This is used for suggesting previously used items during input.

property	datatype	description
name	string	Guess you can get that
amount	number	as well as this
id	number	unique id to identify item
onShoppinglist	boolean	if the item gets displayed in the shoppinglist

Authentication

Authentication is done via a GET request with basic auth credentials to /api/auth/login. With correct credentials the response will be a JSON web token (JWT) which can be used to access all other resources like (REST and socket.io). The token has to be sent in each HTTP request or the socket connect call as a Bearer Token authorization header.