# Integration testing guide MailSlurp gives QA and release teams real inboxes, real phone numbers, deterministic wait methods, and message quality tooling. The goal is not just "can I receive one email" but "can I prove the whole workflow behaved correctly before we ship." ![email testing](/assets/email-testing.jpeg) ## What teams use MailSlurp for - Signup and verification flows that send email or SMS - Password reset and magic-link journeys - OTP and MFA checks - Notification and transactional email assertions - Release gates for delivery, rendering, and message quality ## Core release workflow ### 1. Create isolated inboxes or phone numbers per run Fresh resources keep tests deterministic and make it easy to trace failures back to one build, one suite, or one campaign. ```typescript const inbox = await mailslurp.createInbox(); // { id: '123', emailAddress: '123@mailslurp.com' } ``` Best practice: - Use one inbox per test run or scenario when you can. - Use expiring inboxes for short-lived suites. - Keep naming and tags aligned with your CI pipeline or release identifier. ### 2. Wait for real messages instead of sleeping MailSlurp wait methods let you block until a matching message arrives. This is what removes brittle `sleep()` calls from browser or API tests. ```javascript // wait for the latest unread sms const [sms] = await mailslurp.waitController.waitForSms({ waitForSmsConditions: { count: 1, unreadOnly: true, phoneNumberId: phoneNumber.id, timeout: 30_000 } }); // extract a code from body with regex expect(sms.body).toContain('Your code: 123'); const [, code] = /.+:\s([0-9]{3})/.exec(sms.body); expect(code).toEqual('123'); ``` Use wait methods when you need to assert: - a message arrived - the recipient was correct - the subject or sender matched expectations - a code or link can be extracted and used in the next test step ### 3. Open, inspect, and validate message content After a message lands, teams usually do one of three things: - extract links or OTP codes - open preview URLs for visual checks - validate content quality such as links, images, and supported email features ```typescript const { // load this in a browser to view teh rendered HTML and interact with it plainHtmlBodyUrl, // or view full SMTP message rawSmtpMessageUrl } = await mailslurp.emailController.getEmailPreviewURLs({ emailId: email.id! }); ``` ```typescript const { result } = await mailslurp.emailController.checkEmailBodyFeatureSupport({ emailId: email.id }) expect(result.detectedFeatures).toContain(EmailFeatureSupportResultDetectedFeaturesEnum.html_doctype) expect(result.featurePercentages.find(it => it.status === EmailFeatureSupportStatusPercentageStatusEnum.SUPPORTED)?.percentage).toBeGreaterThan(50) ``` Then deepen the check with: - [Email audit](/docs/email-audit/) for broken links, images, and quality review - [Device previews](/docs/device-renders/) for client and viewport differences - [Email compatibility](/docs/email-feature-check/) for feature support checks ### 4. Add release and post-send confidence checks Single-message waits are useful in tests. Release teams usually add broader controls before launch: - [Deliverability tests](/docs/deliverability-test/) for expectation-based pass/fail checks across inbox or phone cohorts - [Campaign Probe](/docs/campaign-probe/) for live campaign capture and review - [Domain Monitor](/docs/domain-monitor/) and [Reputation](/docs/reputation/) for sender-health monitoring ## Example projects

Csharp Dotnet Core2 Seleniumcsharp example repository: csharp-dotnet-core2-selenium Csharp Playwright Nunit Sms Otpcsharp example repository: csharp-playwright-nunit-sms-otp Csharp Specflow Mstest Seleniumcsharp example repository: csharp-specflow-mstest-selenium Java Gradle Junit5java example repository: java-gradle-junit5 Java Maven Junit4java example repository: java-maven-junit4 Java Maven Seleniumjava example repository: java-maven-selenium Java Testng Seleniumjava example repository: java-testng-selenium Javascript Cypress Jsjavascript example repository: javascript-cypress-js Javascript Cypress Js Open Emailjavascript example repository: javascript-cypress-js-open-email Javascript Cypress Mailslurp Pluginjavascript example repository: javascript-cypress-mailslurp-plugin Javascript Cypress Newsletter Signupjavascript example repository: javascript-cypress-newsletter-signup Javascript Cypress Sms Testingjavascript example repository: javascript-cypress-sms-testing Javascript Testcafejavascript example repository: javascript-testcafe Javascript Webdriver Iojavascript example repository: javascript-webdriver-io Php Composer Phpunitphp example repository: php-composer-phpunit Php Laravel Phpunitphp example repository: php-laravel-phpunit Playwright Codegen Recorder Nocodeplaywright example repository: playwright-codegen-recorder-nocode Playwright Email Testingplaywright example repository: playwright-email-testing Playwright Lowcode Testingplaywright example repository: playwright-lowcode-testing Playwright Sms Testingplaywright example repository: playwright-sms-testing Python2 Pytestpython2 example repository: python2-pytest Python3 Django Playwrightpython3 example repository: python3-django-playwright Python3 Robotframeworkpython3 example repository: python3-robotframework Ruby Capybara Cucumber Seleniumruby example repository: ruby-capybara-cucumber-selenium Ruby Cucumber Testruby example repository: ruby-cucumber-test Rust Selenium Email Testingrust example repository: rust-selenium-email-testing Totp Mfa Auth0 Seleniumtotp example repository: totp-mfa-auth0-selenium

## Test framework guides - [Cypress](/docs/cypress-mailslurp/) - [Playwright](/docs/playwright/) - [Selenium](/docs/selenium/) - [WebdriverIO](/docs/webdriverio/) - [TestCafe](/docs/testcafe/) - [Pytest](/docs/pytest/) - [PHPUnit](/docs/phpunit/) - [JUnit](/docs/junit/) - [TestNG](/docs/testng/) ## Platform and runner guides - [CodeceptJS](/docs/codeceptjs/) - [Robot Framework](/docs/robot-framework/) - [Browserstack](/docs/browserstack/) - [Tricentis Testim](/docs/testim/) - [ACCELQ](/docs/accelq/) - [SmartBear Reflect](/docs/reflect-run/) - [UiPath](/docs/uipath/) - [ReadyAPI](/docs/readyapi/) - [Power Automate](/docs/power-automate/) - [MuleSoft / Anypoint](/docs/mulesoft/) ## Additional example-first frameworks - [Codeception example project](https://github.com/mailslurp/examples/tree/master/php-codeception-acceptance) - [Vitest wait methods example](https://github.com/mailslurp/examples/tree/master/wait-for-methods-vitest) - [Ruby Cucumber example project](https://github.com/mailslurp/examples/tree/master/ruby-cucumber-test) - [Capybara + Cucumber + Selenium example](https://github.com/mailslurp/examples/tree/master/ruby-capybara-cucumber-selenium) - [More examples](/docs/examples/) ## Practical patterns that reduce flakiness - Set explicit wait timeouts that reflect real delivery behavior in your environment. - Isolate inboxes or phone numbers so tests do not compete for the same messages. - Match on concrete fields such as recipient, subject, or unread status. - Keep message extraction helpers in shared test utilities instead of duplicating regex and parsing logic. - Use broader delivery checks before major releases instead of relying only on one test inbox. ## Related docs - [Deliverability tests](/docs/deliverability-test/) - [Wait for methods](/docs/wait-for/) - [Device previews](/docs/device-renders/) - [Email audit](/docs/email-audit/) - [MFA/TOTP devices](/docs/totp/)