Loopback-modeltester

Loopback model unit testing that work with a JSON files

Getting Started

This package is available in the Node Package Repository and can be easily installed with npm or yarn.

$ npm i loopback-modeltester
# or
$ yarn add loopback-modeltester

The first step is to create a test/test.js file at the root of your project with the following content:

// Setup env to development (maybe required by your loopback configuration)
process.env.NODE_ENV = 'development';

// Require The package
const loopbackTest = require('loopback-modeltester');

// Require Loopback server (app)
const app = require('../server/server');

// Require one or multiple JSON that describe your tests!
const modelTest = require('./model-tests.json');

// Declare a new test ! ('api' is the REST base path of Loopback)
const test = new loopbackTest(app, 'api');

// Catch error
test.on('error', console.error);

// Optionaly set a default payload for every tests!
test.defaultPayload({
    headers: {
        foo: 'bar'
    }
});

// Load your JSON test!
test.load(modelTest);

Find a complete JSON example in the root example repository.

API Example

Set a context variable before test execution

test.setVar('defaultUser', 'GENTILHOMME Thomas');
// Now use ${defaultUser} in your test!

Extend

Extend a specific test with some properties (it will merge every properties).

test.extend('customPayload01', {
    expect: {
        statusCode: 500,
        duration: 100,
        bodyType: 'Object',
        properties: {
            error: {
                type: 'String',
                value: 'An error occured on the Server!'
            }
        }
    }
});

And use it on your test by using the property extends

Before/After test execution

Execute action before or after the test by defining after or/and before AsyncFunction setter.

const test = new loopbackTest(app, 'db', 'Collection');
test.after = async function deleteCols(DB) {
	const colList = await DB.listCollections().toArray();
	for(const col of colList) {
		if(col.name === 'system.indexes') {
			continue;
		}
		await DB.dropCollection(col.name);
	}
};

Note: DB Argument is only available when a defaultModel name has been given in the constructor

Documentation

For each tests, all followings keys are allowed. All fields based upon JavaScript types are checked with the lib @sindresorhus/is (So check this package to be sure you entered the right type).

Key	Type	Default Value	Description
title	String	N.A	Test title
skip	Boolean	false	Skip or not the test
break	Boolean	false	Break or pause your test
debug	Boolean	false	Debug the rest by logging headers and body properties
method	String	GET	The default HTTP Verbose method
model	String	N.A	The model name in the plural form
extends	Array	N.A	Array of extensions name
url	String	N.A	The request url
file	Object	N.A	FormData to upload a file
expect	Object	N.A	The expected response from the request
form	Object	N.A	Request form (url-encoded)..
formData	Object	N.A	Request formData
variables	Array	N.A	Variables to assign to the context based upon the Body response

Expect properties

Key	Type	Default Value	Description
statusCode	Number	200	The expected HTTP status code
duration	Number	N.A	The expected baseline duration of the HTTP Request
bodyType	String	N.A	The expected body type (JavaScript)
headers	Object	N.A	All headers key expected, with the value not matched explicitely
properties	Object	N.A	All body properties expected

Properties values can be JavaScript types or an Object. Take the following example :

{
  "error": "null",
  "insertedCount": {
    "type": "Number",
    "value": 1
  },
  "insertedId": "String"
}

Variables

Variables assigned to the context can be used on different fields :

• URL
• Headers values
• Expected properties values

VSCode configuration

If you want JSON completion, you can configure intellisence with JSON Schema. Edit your configuration and put this:

"json.schemas": [
    {
        "fileMatch": [
            "*.lb_tests.json"
        ],
        "url": "./node_modules/loopback-modeltester/schema.json"
    },
]