What is node-mocks-http?
The node-mocks-http package is a tool for creating mock HTTP objects for testing purposes in Node.js applications. It allows developers to simulate HTTP requests and responses, making it easier to test Express.js middleware and route handlers without needing a real HTTP server.
What are node-mocks-http's main functionalities?
Mocking HTTP Requests
This feature allows you to create a mock HTTP request object. You can specify the method, URL, and parameters to simulate different types of requests.
const httpMocks = require('node-mocks-http');
const request = httpMocks.createRequest({
method: 'GET',
url: '/user/42',
params: {
id: '42'
}
});
console.log(request.method); // 'GET'
console.log(request.url); // '/user/42'
console.log(request.params.id); // '42'
Mocking HTTP Responses
This feature allows you to create a mock HTTP response object. You can set the status code and send data, and then inspect the response to verify its properties.
const httpMocks = require('node-mocks-http');
const response = httpMocks.createResponse();
response.status(200).send('OK');
console.log(response._getStatusCode()); // 200
console.log(response._getData()); // 'OK'
Mocking HTTP Headers
This feature allows you to create a mock HTTP request with specific headers. You can then inspect the headers to ensure they are set correctly.
const httpMocks = require('node-mocks-http');
const request = httpMocks.createRequest({
headers: {
'content-type': 'application/json'
}
});
console.log(request.headers['content-type']); // 'application/json'
Mocking HTTP Cookies
This feature allows you to create a mock HTTP request with cookies. You can then inspect the cookies to ensure they are set correctly.
const httpMocks = require('node-mocks-http');
const request = httpMocks.createRequest({
cookies: {
token: '12345'
}
});
console.log(request.cookies.token); // '12345'
Other packages similar to node-mocks-http
supertest
Supertest is a popular library for testing HTTP endpoints. It provides a high-level abstraction for testing HTTP, making it easy to send requests and assert responses. Unlike node-mocks-http, Supertest actually sends HTTP requests to a server, which can be useful for end-to-end testing.
nock
Nock is a library for HTTP mocking and expectations. It allows you to intercept HTTP requests and provide predefined responses. Nock is more focused on mocking external HTTP requests, whereas node-mocks-http is more focused on creating mock request and response objects for internal testing.
sinon
Sinon is a versatile library for creating spies, stubs, and mocks. While it is not specifically designed for HTTP mocking, it can be used in conjunction with other libraries to mock HTTP requests and responses. Sinon provides more general-purpose mocking capabilities compared to node-mocks-http.
Mock 'http' objects for testing Express
routing functions, but could be used for testing any
Node.js web server applications that have
code that requires mockups of the request
and response
objects.
Installation
This project is available as a
NPM package.
$ npm install --save-dev node-mocks-http
Our example includes --save-dev
based on the assumption that node-mocks-http will be used as a development dependency..
After installing the package include the following in your test files:
var httpMocks = require('node-mocks-http');
Usage
Suppose you have the following Express route:
app.get('/user/:id', routeHandler);
And you have created a function to handle that route's call:
var routeHandler = function( request, response ) { ... };
You can easily test the routeHandler
function with some code like
this using the testing framework of your choice:
exports['routeHandler - Simple testing'] = function(test) {
var request = httpMocks.createRequest({
method: 'GET',
url: '/user/42',
params: {
id: 42
}
});
var response = httpMocks.createResponse();
routeHandler(request, response);
var data = JSON.parse( response._getData() );
test.equal("Bob Dog", data.name);
test.equal(42, data.age);
test.equal("bob@dog.com", data.email);
test.equal(200, response.statusCode );
test.ok( response._isEndCalled());
test.ok( response._isJSON());
test.ok( response._isUTF8());
test.done();
};
Design Decisions
We wanted some simple mocks without a large framework.
We also wanted the mocks to act like the original framework being
mocked, but allow for setting of values before calling and inspecting
of values after calling.
For Developers
We are looking for more volunteers to bring value to this project,
including the creation of more objects from the
HTTP module.
This project doesn't address all features that must be
mocked, but it is a good start. Feel free to send pull requests,
and a member of the team will be timely in merging them.
If you wish to contribute please read our Contributing Guidelines.
Release Notes
Most releases fix bugs with our mocks or add features similar to the
actual Request
and Response
objects offered by Node.js and extended
by Express.
Most Recent Releast Notes
License
Licensed under MIT.