Mock a call to a service with npm nock and npm superagent using a POST

nock.superagent.post.jest.test.js

import nock from 'nock';
import request from 'superagent';

    describe('Calling AWS SDK to sign up a user', () => {
        
        let postData = {username: '[email protected]', password: '@Password1'};
        let _request = null;
        
        beforeEach(() => {
            nock('http://aws-sdk.aws.com/', {
                reqheaders: {
                    "content-type": "application/json",
                }          
            })
            .post('/cognito/signUpUser')
            .reply(200, {
                ok: true,
                cognito_id: 123456,
                cognito_user: '[email protected]'
            });

            _request = request
                .post('http://aws-sdk.aws.com/cognito/signUpUser')
                .set('accept', 'json');
            
        }); //end beforeEach
        

        it('Should return a 200', () => {

            _request
                .send(JSON.stringify(postData))
                .end((err, res) => {
                    if(err){
                        console.log('------ ERROR : ')
                        console.log(err);
                    } else {
                        expect(res.statusCode).toEqual(200);
                    }
                })

        })

        it('Should return a cognito id of 123456', () => {
            _request
                .send(JSON.stringify(postData))
                .end((err, res) => {
                    if(err){
                        console.log('---- ERROR : ');
                        console.log(err);
                    } else {
                        expect(res.body.cognito_id).toBe('123456')
                    }
                })
        });

        it('Should return a cognito user of "[email protected]', () => {
            _request
                .send(JSON.stringify(postData))
                .end((err, res) => {
                    if(err){
                        console.log('---- ERROR : ');
                        console.log(err);
                    } else {
                        expect(res.body.cognito_user).toBe('[email protected]');
                    }
                })
        })
    }) //end describe Calling AWS SDK to sign up a user