What is json-server?
json-server is a full fake REST API with zero coding in less than 30 seconds. It allows you to create a mock REST API using a simple JSON file as the database.
What are json-server's main functionalities?
Create a Fake REST API
This code sets up a basic JSON server that reads from a 'db.json' file and serves it as a REST API. The server listens on port 3000.
const jsonServer = require('json-server');
const server = jsonServer.create();
const router = jsonServer.router('db.json');
const middlewares = jsonServer.defaults();
server.use(middlewares);
server.use(router);
server.listen(3000, () => {
console.log('JSON Server is running');
});
Custom Routes
This code demonstrates how to use custom routes with json-server. The rewriter middleware is used to map custom routes to the default routes.
const jsonServer = require('json-server');
const server = jsonServer.create();
const router = jsonServer.router('db.json');
const middlewares = jsonServer.defaults();
server.use(middlewares);
server.use(jsonServer.rewriter({
'/api/*': '/$1',
'/blog/:resource/:id/show': '/:resource/:id'
}));
server.use(router);
server.listen(3000, () => {
console.log('JSON Server is running');
});
Add Custom Middleware
This code adds custom middleware to the JSON server. In this example, a timestamp is added to the request body for POST requests.
const jsonServer = require('json-server');
const server = jsonServer.create();
const router = jsonServer.router('db.json');
const middlewares = jsonServer.defaults();
server.use(middlewares);
server.use((req, res, next) => {
if (req.method === 'POST') {
req.body.createdAt = Date.now();
}
next();
});
server.use(router);
server.listen(3000, () => {
console.log('JSON Server is running');
});
Other packages similar to json-server
miragejs
Mirage JS is a client-side server to build, test and share a complete working JavaScript application without having to rely on any backend services. Unlike json-server, which is more focused on quickly setting up a REST API, Mirage JS is designed to work seamlessly with frontend frameworks like React, Vue, and Angular.
prism
Prism is a package for creating mock servers based on OpenAPI and API Blueprint specifications. It allows you to create a mock server that can validate requests and responses against your API specification. Unlike json-server, which uses a JSON file as a database, Prism uses API specifications to generate mock responses.
JSON Server
Give it a JSON or JS file and it will serve it through REST routes.
Created with <3 for front-end developers who need a flexible back-end for quick prototyping and mocking.
Powers JSONPlaceholder
Usage
CLI
Create a db.json
file:
{
"posts": [
{ "id": 1, "body": "foo" }
]
}
Then run json-server db.json
and go to http://localhost:3000/posts/1
.
You should get { "id": 1, "body": "foo" }
.
Module
var server = require('json-server');
server({
posts: [
{ id: 1, body: 'foo' }
]
}).listen(3000);
Features
- Lets you use plain JSON or simple JS file
- Supports GET but also POST, PUT, DELETE and even PATCH requests
- Can be used from anywhere through cross domain requests (JSONP or CORS)
- Can load remote JSON files (JSON Generator, ...)
- Can be deployed on Nodejitsu, Heroku, ...
Install
$ npm install -g json-server
CLI options
json-server <source>
Examples:
json-server db.json
json-server file.js
json-server http://example.com/db.json
Options:
--help, -h Show help
--version, -v Show version number
--port, -p Set port [default: 3000]
Input
Here's 2 examples showing how to format JSON or JS seed file:
JSON
{
"posts": [
{ "id": 1, "body": "foo" },
{ "id": 2, "body": "bar" }
],
"comments": [
{ "id": 1, "body": "baz", "postId": 1 },
{ "id": 2, "body": "qux", "postId": 2 }
]
}
JS
module.exports = function() {
var data = {};
data.posts = [];
data.posts.push({ id: 1, body: 'foo' });
return data;
}
JSON Server expects JS files to export a function that returns an object.
JS files are useful if you need to programmaticaly create a lot of data.
Available routes
Let's say we have posts
, here's the routes you can use.
GET /posts
GET /posts?title=jsonserver&author=typicode
GET /posts/1/comments
GET /posts/1
POST /posts
PUT /posts/1
PATCH /posts/1
DEL /posts/1
To slice resources, add _start
and _end
.
GET /posts?_start=0&_end=10
GET /posts/1/comments?_start=0&_end=10
To sort resources, add _sort
and _order
(ascending order by default).
GET /posts?_sort=views&_order=DESC
GET /posts/1/comments?_sort=votes&_order=ASC
To make a full-text search on resources, add q
.
GET /posts?q=internet
Returns database.
GET /db
Returns default index file or content of ./public/index.html
(useful if you need to set a custom home page).
GET /
For more routes usage examples, have a look at JSONPlaceholder's README.
Links
Articles
Projects