MailSlurp Cypress Plugin

Official MailSlurp email plugin for Cypress JS. Create real test email accounts. Send and receive emails and attachments in Cypress tests. For more advanced usage see the standard MailSlurp library.

Install

npm install --save-dev cypress-mailslurp

Then include the plugin in your cypress/support/index.{js,ts} file.

import "cypress-mailslurp";

See the example project for setup help.

Setup

MailSlurp is free but requires an API Key. Get yours by creating a free account.

API Key

Set the environment variable CYPRESS_MAILSLURP_API_KEY or use the cypress.json file env property:

Environment variable

CYPRESS_MAILSLURP_API_KEY=your-api-key cypress run

Cypress env property

{
  "env": {
    "MAILSLURP_API_KEY": "your-mailslurp-api-key"
  }
}

Timeouts

MailSlurp requires timeouts to wait for inbound emails. Set timeouts in cypress.json:

{
  "defaultCommandTimeout": 30000,
  "responseTimeout": 30000,
  "requestTimeout": 30000
}

Typescript support

MailSlurp adds the mailslurp command to the Cypress cy object. Include the type definition reference comment in your test file or support index.ts:

/// <reference types="cypress-mailslurp" />

Or define the type yourself like so:

import { MailSlurp } from "mailslurp-client";

declare global {
    namespace Cypress {
        interface Chainable {
            mailslurp: () => Promise<MailSlurp>;
        }
    }
}

Usage

The Cypress MailSlurp plugin provide one simple command attached to the Cypress object: cy.mailslurp(). This method returns a MailSlurp client instance that has all the same methods and properties as the official MailSlurp client. Use the command with the then() method to access the instance:

cy.mailslurp().then(mailslurp => mailslurp.createInbox() /* etc */)

Common methods

The client chained by the cy.mailslurp() has all the same methods and properties as the official MailSlurp client. See the Javascript documentation for a full API reference or see the examples below.

The MailSlurp client has a number of convenience methods and also exposes the full MailSlurp API as controllers. See the class reference for full method documentation.

Create email address

You can create test email accounts with MailSlurp by creating inboxes. Inboxes have an id and an emailAddress. Save the id for later use when fetching or sending emails.

cy.mailslurp()
    .then(mailslurp => mailslurp.createInbox())
    .then(inbox => expect(inbox.emailAddress).to.contain("@mailslurp"));

Receive emails in tests

Use the waitFor methods to wait for emails for an inbox. See the email object docs for full properties.

cy.mailslurp()
    .then(mailslurp => mailslurp.waitForLatestEmail(inboxId, 30000, true))
    .then(email => expect(email.subject).to.contain("My email"))

Send emails

To send emails in Cypress tests first create an inbox then use the sendEmail method.

cy.mailslurp()
    .then(mailslurp => mailslurp.sendEmail(inboxId, { to: ['test@example.com'], subject: 'test', body: '<html></html>', isHTML: true }))

Accessing more methods

To access all the MailSlurp methods available in the REST API and Javascript Client use the controllers on the mailslurp instance.

cy.mailslurp().then(mailslurp => mailslurp.attachmentController.uploadAttachment({
    base64Contents: fileBase64Encoded,
    contentType: 'text/plain',
    filename: basename(pathToAttachment)
}))

Storing values between tests

Cypress has a unique async nature. To use MailSlurp effectively with Cypress chain your commands using then() or store results in wrapped aliases using wrap() and as().

before(function () {
    return cy.mailslurp()
        .then(mailslurp => mailslurp.createInbox())
        .then(inbox => {
            // save inbox id and email address to this (make sure you use function and not arrow syntax)
            cy.wrap(inbox.id).as('inboxId')
            cy.wrap(inbox.emailAddress).as('emailAddress')
        })
});
it("01 - can load the demo application", function () {
    // get wrapped email address and assert contains a mailslurp email address
    expect(this.emailAddress).to.contain("@mailslurp");
    // visit the demo application
    cy.visit("https://playground.mailslurp.com")
    cy.title().should('contain', 'React App');
});

Note: using wrap to store values accross test methods requires you to use function syntax instead of () => arrow syntax. This ensure that this is dynamically scoped and includes the aliased variables.

Example test

Here is an example of testing user sign up on a demo application hosted at playground.mailslurp.com. It creates a new MailSlurp inbox before all tests and saves the inbox.id and inbox.emailAddress to a shared text context using the cy.wrap().as() methods. It then loads the demo application, fills out a sign up form using the email address and receives a user confirmation code. We wait for the email to arrive using the waitForLatestEmail method and then extract a confirmation code that can be submitted to the app to confirm the user.

/// <reference types="cypress" />
/// <reference types="../../src" />
describe("user sign up test with mailslurp plugin", function () {
    // use cypress-mailslurp plugin to create an email address before test
    before(function () {
        return cy.mailslurp()
            .then(mailslurp => mailslurp.createInbox())
            .then(inbox => {
                // save inbox id and email address to this (make sure you use function and not arrow syntax)
                cy.wrap(inbox.id).as('inboxId')
                cy.wrap(inbox.emailAddress).as('emailAddress')
            })
    });
    it("01 - can load the demo application", function () {
        // get wrapped email address and assert contains a mailslurp email address
        expect(this.emailAddress).to.contain("@mailslurp");
        // visit the demo application
        cy.visit("https://playground.mailslurp.com")
        cy.title().should('contain', 'React App');
    });
    // use function instead of arrow syntax to access aliased values on this
    it("02 - can sign up using email address", function () {
        // click sign up and fill out the form
        cy.get("[data-test=sign-in-create-account-link]").click()
        // use the email address and a test password
        cy.get("[name=email]").type(this.emailAddress).trigger('change');
        cy.get("[name=password]").type('test-password').trigger('change');
        // click the submit button
        cy.get("[data-test=sign-up-create-account-button]").click();
    });
    it("03 - can receive confirmation code by email", function () {
        // app will send user an email containing a code, use mailslurp to wait for the latest email
        cy.mailslurp()
            // use inbox id and a timeout of 30 seconds
            .then(mailslurp => mailslurp.waitForLatestEmail(this.inboxId, 30000, true))
            // extract the confirmation code from the email body
            .then(email => /.*verification code is (\d{6}).*/.exec(email.body!!)!![1])
            // fill out the confirmation form and submit
            .then(code => {
                cy.get("[name=code]").type(code).trigger('change');
                cy.get("[data-test=confirm-sign-up-confirm-button]").click();
            })
    });
    // fill out sign in form
    it("04 - can sign in with confirmed account", function () {
        // use the email address and a test password
        cy.get("[data-test=username-input]").type(this.emailAddress).trigger('change');
        cy.get("[data-test=sign-in-password-input]").type('test-password').trigger('change');
        // click the submit button
        cy.get("[data-test=sign-in-sign-in-button]").click();
    });
    // can see authorized welcome screen
    it("05 - can see welcome screen", function () {
        // click sign up and fill out the form
        cy.get("h1").should("contain", "Welcome");
    });
});