True End-to-End Testing in Scala

Video: https://parleys.com/play/5460c793e4b0dab81f955667

Exploring what end-to-end tests are, why they are important for Scala apps, and how to write them. A talk given at Scalapeno 2014. Talk is accompanied by a code example: https://github.com/orrsella/scala-e2e-testing

Abstract:

It seems that by 2014 we have all come to the realization that testing is good, and today no reputable library/framework will be released without comprehensive tests. Whether you're developing using TDD or not, you're probably writing tests in some capacity. We have a plethora of testing libraries and tools that make writing tests in Scala extremely easy.

In this talk we will show how we can take our unit/integration tests a step further, and see how to test our applications end-to-end. Scala is a prime candidate for end-to-end testing, having all the right pieces in place: an easily extendable build tool (SBT), fluent DSL testing libraries (Specs2/ScalaTest), and the power/tooling of the JVM behind it.

We will see how to approach testing our application from the outside, and touch on concepts such as: the Test Harness, abstracting our SUT (System Under Test) by using test Drivers, using Simplicators for testing against external dependencies, and more. We will put everything together by using tools such as: SBT, Ansible and Vagrant.

Transcript

1. TRUE END-TO-END TESTING SCALA Orr Sella IN Scalapeño 2014
2. AGENDA WHAT ARE THEY WHY WE NEED THEM HOW TO WRITE THEM END-TO-END TESTS TEST HARNESS DRIVERS FAKES …
3. AGENDA WHAT ARE THEY WHY WE NEED THEM HOW TO WRITE THEM END-TO-END TESTS TEST HARNESS DRIVERS FAKES … CONCRETE EXAMPLE github.com/orrsella/scala-e2e-testing
4. BIG SUBJECT, WE CAN’T COVER EVERYTHING Disclaimer
5. Why SCALA & END-TO- END TESTS 1 THE APPS Typical Scala applications are ripe for end-to- end tests ! THE LANGUAGE & ECOSYSTEM Build tools, testing libraries and language features are a great fit 2
6. SOME TERMINOLOGY First,
7. The Bible: GOOS INTRO TO TDD ! TESTING TECHNIQUES ! LOTS OF CODE & EXAMPLES
8. LEVELS OF THE TESTINGKNOWN TO MAN 1 UNIT Do our objects do the right thing? ! INTEGRATION Does our code work against code we can’t change? ! END-TO-END Does the whole system work? 2 3 (not really)
9. RIGHT BALANCE WHAT IS THE OF THE THREE?
10. INVERSE THE ICE CREAMCONE (or pyramid) NUMBER OF TESTS
11. INVERSE THE ICE CREAMCONE (or pyramid) END- TO-END INTEGRATION UNIT NUMBER OF TESTS
12. INVERSE THE ICE CREAMCONE (or pyramid) END- TO-END INTEGRATION UNIT MANUAL TESTING (if you must) NUMBER OF TESTS
13. END-TO-END WHAT ARE TESTS?
14. END-TO-END TESTS Interact with the system from the outside Black Box MOST IMPORTANTLY: Exercising both the system and the process by which it’s built and deployed Include interaction with external environment
15. AUTOMATIC AN IDEAL BUILDWOULD 1 Compile and unit-test the code Integrate and package the system Perform a production-like deployment to a realistic environment Exercise the system through its external access points 2 3 4
16. AUTOMATIC AN IDEAL BUILDWOULD 1 Compile and unit-test the code Integrate and package the system Perform a production-like deployment to a realistic environment Exercise the system through its external access points 2 3 4
17. THIS SOUNDS LIKE A LOT OF WORK Whoa,
18. THIS SOUNDS LIKE A LOT OF WORK Whoa, IT IS.
19. IS IT WORTH IT? But,
20. IS IT WORTH IT? But, YES. (I hope to convince you)
21. END-TO-END WHY ARE TESTS SO IMPORTANT?
22. REASONS HERE ARE3 MAIN (many more...)
23. FLUSH OUT THE UNKNOWNS 1 Requires asking (and answering) many awkward questions Expose uncertainty early, including technical and organizational risks Forces to understand how a system fits into the world Identify all the integration (read: potential failure) points
24. FLUSH OUT THE UNKNOWNS 1 Requires asking (and answering) many awkward questions Expose uncertainty early, including technical and organizational risks Forces to understand how a system fits into the world Identify all the integration (read: potential failure) points EXAMPLE IN 3 SLIDES
25. FEEDBACK & CONFIDENCE 2 Feedback that would otherwise only show in staging/production Safety net of system-wide regression Assurance that our chosen technology stack (“plumbing”) works as expected Confidence to make “risky” system-wide changes (e.g: swap datastore, application server)
26. FORCED AUTOMATION 3 Everything must be automated so it can be tested Crucial for deployment which is error-prone Automatic Build-Deploy-Test cycle means we can ship frequently
27. TIME FOR A CONCRETE EXAMPLE:
28. TIME FOR A CONCRETE EXAMPLE: Memento
29. TIME FOR A CONCRETE EXAMPLE: Memento github.com/orrsella/scala-e2e-testing
30. NOTE-TAKING WEB SERVICE Memento?
31. NOTE-TAKING WEB SERVICE Memento? STORE, RETRIEVE, SEARCH, TRANSLATE
32. NOTE-TAKING WEB SERVICE Memento? STORE, RETRIEVE, SEARCH, TRANSLATE “MICROSERVICE”
33. NOTE-TAKING WEB SERVICE Memento? STORE, RETRIEVE, SEARCH, TRANSLATE “MICROSERVICE” REST API
34. LOAD BALANCER HAPROXY REVERSE PROXY NGINX APP SERVER FINATRA DATASTORE ELASTICSEARCH TRANSLATION SERVICE YANDEX
35. LOAD BALANCER HAPROXY REVERSE PROXY NGINX APP SERVER FINATRA DATASTORE ELASTICSEARCH TRANSLATION SERVICE YANDEX SCALA!..
36. LOAD BALANCER HAPROXY REVERSE PROXY NGINX APP SERVER FINATRA DATASTORE ELASTICSEARCH TRANSLATION SERVICE YANDEX SCALA!.. PRETTY STRAIGHTFORWARD
37. WHAT CAN POSSIBLY GO WRONG & BE MISCONFIGURED? Ok. So. i.e. integration (failure) points
38. LOAD BALANCER HAPROXY PORT 80 /ETC/HAPROXY/ HAPROXY.CFG LIST OF REVERSE PROXIES:PORTS /ETC/DEFAULT/ HAPROXY
39. REVERSE PROXY NGINX APP SERVER FINATRA PROXY PORT 7770 /ETC/NGINX/ NGINX.CONF INIT.D SCRIPT /ETC/NGINX/ SITES-AVAILABLE JAVA APPLICATION.CONF LOGBACK.XML DEPLOY NEW VERSION
40. DATASTORE ELASTICSEARCH TRANSLATION SERVICE YANDEX PORT 9300 MAPPING URL API KEY /ETC/ELSATICSEARCH.YML JAVA
41. (just a partial list…)
42. SO A LOT CAN GO WRONG Ok, (read: will)
43. SO A LOT CAN GO WRONG Ok, (read: will) WE WANT OUR END-TO-END TESTS TO EXERCISE ALL OF THIS!
44. HOW DO WE TEST ALL OF THIS END-TO-END?
45. HOW DO WE TEST ALL OF THIS END-TO-END? here is one approach…
46. HOW DO WE TEST ALL OF THIS END-TO-END? here is one approach… THERE ARE OTHERS
47. HOW DO WE TEST ALL OF THIS END-TO-END? here is one approach… THERE ARE OTHERS BUT THIS IS THE BEST, OBVIOUSLY
48. REQUIRED FOR STEPS END-TO-ENDTESTS 1 BUILD & PACKAGE Package the app for production deployment 2 3 0 VIRTUAL MACHINE Fire-up a local VM instance with production-like env CONFIGURATION & DEPLOYMENT Run production config and deployment code, having our entire system on one box RUN TESTS Execute end-to-end tests against the VM
49. ORCHESTRATE HOW DO WE ALL OF THIS?
50. THE TEST HARNESS Enter: EXTENSION OF THE BUILD Runs all the necessary setup/teardown actions and the tests themselves ! STANDARD/SIMPLE/SCALA BUILD TOOL Build and package our app (sbt-native-packager) Fire-up the virtual machine (Vagrant) Run configuration and deployment scripts (Ansible) (aka sbt)
51. VAGRANT Meet PORTABLE DEV ENVIRONMENTS Lightweight, reproducible and programmable ! VIRTUALIZATION Wrapper around VirtualBox, VMWare, more ! SIMPLE & QUICK Vagrantfile => `$ vagrant up`
52. 2 CONFIGURATION & DEPLOYMENT Run production config and deployment code, having our entire system on one box STEPS REQUIRED FOR THE END-TO-ENDTESTS BUILD & PACKAGE Package the app for production-like deployment 3 0 RUN TESTS Execute end-to-end tests against the VM 1 VIRTUAL MACHINE Fire-up a local VM instance with production-like env
53. Test Harness: MANAGING VAGRANT SBT // project/Vagrant.scala ! object Vagrant { ! private lazy val vagrant = settingKey[Vagrant]("vagrant") ! lazy val settings = Seq( test in EndToEndTest <<= (test in EndToEndTest).dependsOn(publishLocal), testOptions in EndToEndTest += Tests.Setup(() => vagrant.value.setup()), testOptions in EndToEndTest += Tests.Cleanup(() => vagrant.value.cleanup()) ) }
54. Test Harness: MANAGING VAGRANT SBT // project/Vagrant.scala ! object Vagrant { ! private lazy val vagrant = settingKey[Vagrant]("vagrant") ! lazy val settings = Seq( test in EndToEndTest <<= (test in EndToEndTest).dependsOn(publishLocal), testOptions in EndToEndTest += Tests.Setup(() => vagrant.value.setup()), testOptions in EndToEndTest += Tests.Cleanup(() => vagrant.value.cleanup()) ) } TEARDOWN HOOK SETUP HOOK
55. Test Harness: MANAGING VAGRANT SBT class Vagrant(vagrantFile: File) { ! // cli method wrappers private def up() = Process("vagrant" :: "up" :: Nil, dir)! private def provision() = Process("vagrant" :: "provision" :: Nil, dir)! ! def setup(): Unit = { prevStatus = status() prevStatus match { case Running => provision() case Saved => up(); provision() case NotCreated => up() case Unknown => up() } } ! def cleanup(): Unit = if (prevStatus != Running) suspend() }
56. Test Harness: MANAGING VAGRANT SBT class Vagrant(vagrantFile: File) { ! // cli method wrappers private def up() = Process("vagrant" :: "up" :: Nil, dir)! private def provision() = Process("vagrant" :: "provision" :: Nil, dir)! ! def setup(): Unit = { prevStatus = status() prevStatus match { case Running => provision() case Saved => up(); provision() case NotCreated => up() case Unknown => up() } } ! def cleanup(): Unit = if (prevStatus != Running) suspend() }
57. Test Harness: MANAGING VAGRANT SBT class Vagrant(vagrantFile: File) { ! // cli method wrappers private def up() = Process("vagrant" :: "up" :: Nil, dir)! private def provision() = Process("vagrant" :: "provision" :: Nil, dir)! ! def setup(): Unit = { prevStatus = status() prevStatus match { case Running => provision() case Saved => up(); provision() case NotCreated => up() case Unknown => up() } } ! def cleanup(): Unit = if (prevStatus != Running) suspend() } Tip: VAGRANT STATE “JUGGLING”, SAVES A LOT OF TIME!
58. STEPS REQUIRED FOR THE END-TO-ENDTESTS 1 BUILD & PACKAGE Package the app for production-like deployment 3 0 VIRTUAL MACHINE Fire-up a local VM instance with production-like env RUN TESTS Execute end-to-end tests against the VM 2 CONFIGURATION & DEPLOYMENT Run production config and deployment code, having our entire system on one box
59. DEPLOYMENT THE SCRIPTS CONFIGURATION MANAGEMENT Ensure that our system is configured properly (OS, settings, packages, file system, etc.) ! DEPLOY THE APP Upgrade to the latest version just compiled and packaged, as would be done in production ! APPLICATION CONFIG Configure the application itself the same way it would in production (but with test values) (Provision in Vagrant parlance)
60. ANSIBLE BUT ANY CM TOOL WILL DO Specifically, (Chef, Puppet, Shell scripts)
61. Vagrant.configure(VAGRANTFILE_API_VERSION) do |config| ! config.vm.box = "ubuntu/trusty64" config.vm.network "forwarded_port", guest: 7770, host: 7769 ... ! config.vm.provision "ansible" do |ansible| ansible.playbook = "ansible/site.yml" ansible.inventory_path = "ansible/inventories/vagrant" end ! end Provision: VAGRANTFILE
62. Vagrant.configure(VAGRANTFILE_API_VERSION) do |config| ! config.vm.box = "ubuntu/trusty64" config.vm.network "forwarded_port", guest: 7770, host: 7769 ... ! config.vm.provision "ansible" do |ansible| ansible.playbook = "ansible/site.yml" ansible.inventory_path = "ansible/inventories/vagrant" end ! end Provision: VAGRANTFILE
63. Vagrant.configure(VAGRANTFILE_API_VERSION) do |config| ! config.vm.box = "ubuntu/trusty64" config.vm.network "forwarded_port", guest: 7770, host: 7769 ... ! config.vm.provision "ansible" do |ansible| ansible.playbook = "ansible/site.yml" ansible.inventory_path = "ansible/inventories/vagrant" end ! end Provision: VAGRANTFILE VAGRANT INVOKES THE PROVISIONER
64. CONFIGURATION & DEPLOYMENT Run production config and deployment code, having our entire system on one box BUILD & PACKAGE Package the app for production-like deployment VIRTUAL MACHINE Fire-up a local VM instance with production-like env STEPS REQUIRED FOR THE END-TO-ENDTESTS 3 RUN TESTS Execute end-to-end tests against the VM 2 1 0
65. CONFIGURATION & DEPLOYMENT Run production config and deployment code, having our entire system on one box BUILD & PACKAGE Package the app for production-like deployment VIRTUAL MACHINE Fire-up a local VM instance with production-like env STEPS REQUIRED FOR THE END-TO-ENDTESTS 3 RUN TESTS Execute end-to-end tests against the VM 2 1 0 CHECK OUT CODE EXAMPLE
66. 2 CONFIGURATION & DEPLOYMENT Run production config and deployment code, having our entire system on one box STEPS REQUIRED FOR THE END-TO-ENDTESTS 1 BUILD & PACKAGE Package the app for production-like deployment 0 VIRTUAL MACHINE Fire-up a local VM instance with production-like env 3 RUN TESTS Execute end-to-end tests against the VM
67. WRITING THE Finally, TESTS THEMSELVES
68. GUIDELINES SOME E2E TESTS FOR effective TEST SPARINGLY End-to-End tests are slow; test few “sunny-day” scenarios ! ABSTRACTION Tests validate features and business logic, not implementation details ! AVOID COUPLING Tests should exercise the system from the outside without reaching for its guts
69. Memento: NOTES CONTROLLERTEST class NotesControllerEndToEndTest extends Specification with NotesControllerDriver with ResponseMatchers { ! "Notes controller" should { "add a note and then successfully get it" in { ! val addResp = anAddNoteRequest.withText("Hello world!").execute() addResp must beOk addResp.noteId must not beEmpty ! val getResp = aGetNoteRequest.withId(addResp.noteId).execute() getResp must beOk getResp.text must_== "Hello world!" } } }
70. Memento: NOTES CONTROLLERTEST class NotesControllerEndToEndTest extends Specification with NotesControllerDriver with ResponseMatchers { ! "Notes controller" should { "add a note and then successfully get it" in { ! val addResp = anAddNoteRequest.withText("Hello world!").execute() addResp must beOk addResp.noteId must not beEmpty ! val getResp = aGetNoteRequest.withId(addResp.noteId).execute() getResp must beOk getResp.text must_== "Hello world!" } } } USING SPECS2
71. Memento: NOTES CONTROLLERTEST class NotesControllerEndToEndTest extends Specification with NotesControllerDriver with ResponseMatchers { ! "Notes controller" should { "add a note and then successfully get it" in { ! val addResp = anAddNoteRequest.withText("Hello world!").execute() addResp must beOk addResp.noteId must not beEmpty ! val getResp = aGetNoteRequest.withId(addResp.noteId).execute() getResp must beOk getResp.text must_== "Hello world!" } } }
72. Memento: NOTES CONTROLLERTEST class NotesControllerEndToEndTest extends Specification with NotesControllerDriver with ResponseMatchers { ! "Notes controller" should { "add a note and then successfully get it" in { ! val addResp = anAddNoteRequest.withText("Hello world!").execute() addResp must beOk addResp.noteId must not beEmpty ! val getResp = aGetNoteRequest.withId(addResp.noteId).execute() getResp must beOk getResp.text must_== "Hello world!" } } } TESTING THE SYSTEM BY USING ITSELF
73. Memento: NOTES CONTROLLERTEST class NotesControllerEndToEndTest extends Specification with NotesControllerDriver with ResponseMatchers { ! "Notes controller" should { "add a note and then successfully get it" in { ! val addResp = anAddNoteRequest.withText("Hello world!").execute() addResp must beOk addResp.noteId must not beEmpty ! val getResp = aGetNoteRequest.withId(addResp.noteId).execute() getResp must beOk getResp.text must_== "Hello world!" } } } TEST IS DECOUPLED FROM THE CONTROLLER API ITSELF BY USING DRIVERS
74. Interact with the SUT directly instead of the test Coupled to the API/protocol Run same test with different drivers Drivers: ABSTRACTING THE SUT
75. Drivers: ABSTRACTING THE SUT trait NotesControllerDriver { ! def anAddNoteRequest = AddNoteRequest() ! case class AddNoteRequest(text: String = "Lorem ipsum") extends Request[AddNoteResponse] { ! val method = HttpMethod.POST val path = "/notes" val params: Map[String, String] = Map() val headers: Map[String, String] = Map() val body: Option[String] = Some("{ \"text\": \"" + text + "\" }") ! def withText(text: String) = copy(text = text) } ... }
76. Drivers: ABSTRACTING THE SUT trait NotesControllerDriver { ! def anAddNoteRequest = AddNoteRequest() ! case class AddNoteRequest(text: String = "Lorem ipsum") extends Request[AddNoteResponse] { ! val method = HttpMethod.POST val path = "/notes" val params: Map[String, String] = Map() val headers: Map[String, String] = Map() val body: Option[String] = Some("{ \"text\": \"" + text + "\" }") ! def withText(text: String) = copy(text = text) } ... } ONLY THE DRIVER INTIMATELY KNOWS THE CONTROLLER
77. Drivers: ABSTRACTING THE SUT trait NotesControllerDriver { ! def anAddNoteRequest = AddNoteRequest() ! case class AddNoteRequest(text: String = "Lorem ipsum") extends Request[AddNoteResponse] { ! val method = HttpMethod.POST val path = "/notes" val params: Map[String, String] = Map() val headers: Map[String, String] = Map() val body: Option[String] = Some("{ \"text\": \"" + text + "\" }") ! def withText(text: String) = copy(text = text) } ... } ONLY THE DRIVER INTIMATELY KNOWS THE CONTROLLER
78. Drivers: ABSTRACTING THE SUT trait NotesControllerDriver { ! def anAddNoteRequest = AddNoteRequest() ! case class AddNoteRequest(text: String = "Lorem ipsum") extends Request[AddNoteResponse] { ! val method = HttpMethod.POST val path = "/notes" val params: Map[String, String] = Map() val headers: Map[String, String] = Map() val body: Option[String] = Some("{ \"text\": \"" + text + "\" }") ! def withText(text: String) = copy(text = text) } ... } ONLY THE DRIVER INTIMATELY KNOWS THE CONTROLLER
79. Drivers: ABSTRACTING THE SUT trait NotesControllerDriver { ! def anAddNoteRequest = AddNoteRequest() ! case class AddNoteRequest(text: String = "Lorem ipsum") extends Request[AddNoteResponse] { ! val method = HttpMethod.POST val path = "/notes" val params: Map[String, String] = Map() val headers: Map[String, String] = Map() val body: Option[String] = Some("{ \"text\": \"" + text + "\" }") ! def withText(text: String) = copy(text = text) } ... } ONLY THE DRIVER INTIMATELY KNOWS THE CONTROLLER class AddNoteResponse(response: Response) extends BaseResponse(response) with JsonResponse { ! lazy val noteId = (json \ "noteId").extract[String] }
80. Drivers: ABSTRACTING THE SUT trait NotesControllerDriver { ! def anAddNoteRequest = AddNoteRequest() ! case class AddNoteRequest(text: String = "Lorem ipsum") extends Request[AddNoteResponse] { ! val method = HttpMethod.POST val path = "/notes" val params: Map[String, String] = Map() val headers: Map[String, String] = Map() val body: Option[String] = Some("{ \"text\": \"" + text + "\" }") ! def withText(text: String) = copy(text = text) } ... } ONLY THE DRIVER INTIMATELY KNOWS THE CONTROLLER class AddNoteResponse(response: Response) extends BaseResponse(response) with JsonResponse { ! lazy val noteId = (json \ "noteId").extract[String] } ONLY THE DRIVER KNOWS THE RESPONSE IS JSON
81. Drivers: ABSTRACTING THE SUT trait NotesControllerDriver { ! def anAddNoteRequest = AddNoteRequest() ! case class AddNoteRequest(text: String = "Lorem ipsum") extends Request[AddNoteResponse] { ! val method = HttpMethod.POST val path = "/notes" val params: Map[String, String] = Map() val headers: Map[String, String] = Map() val body: Option[String] = Some("{ \"text\": \"" + text + "\" }") ! def withText(text: String) = copy(text = text) } ... } ONLY THE DRIVER INTIMATELY KNOWS THE CONTROLLER class AddNoteResponse(response: Response) extends BaseResponse(response) with JsonResponse { ! lazy val noteId = (json \ "noteId").extract[String] } ONLY THE DRIVER KNOWS THE RESPONSE IS JSON OR THE FIELD NAME
82. (back to the test…)
83. Memento: NOTES CONTROLLERTEST class NotesControllerEndToEndTest extends Specification with NotesControllerDriver with ResponseMatchers { ! "Notes controller" should { "add a note and then successfully get it" in { ! val addResp = anAddNoteRequest.withText("Hello world!").execute() addResp must beOk addResp.noteId must not beEmpty ! val getResp = aGetNoteRequest.withId(addResp.noteId).execute() getResp must beOk getResp.text must_== "Hello world!" } } }
84. Memento: NOTES CONTROLLERTEST class NotesControllerEndToEndTest extends Specification with NotesControllerDriver with ResponseMatchers { ! "Notes controller" should { "add a note and then successfully get it" in { ! val addResp = anAddNoteRequest.withText("Hello world!").execute() addResp must beOk addResp.noteId must not beEmpty ! val getResp = aGetNoteRequest.withId(addResp.noteId).execute() getResp must beOk getResp.text must_== "Hello world!" } } }
85. Matchers: ABSTRACTING THE SUT The other side of the Driver, i.e: the response Help decoupling from the protocol, make the test be about features Make test more readable
86. Memento: NOTES CONTROLLERTEST class NotesControllerEndToEndTest extends Specification with NotesControllerDriver with ResponseMatchers { ! "Notes controller" should { "add a note and then successfully get it" in { ! val addResp = anAddNoteRequest.withText("Hello world!").execute() addResp must beOk addResp.noteId must not beEmpty ! val getResp = aGetNoteRequest.withId(addResp.noteId).execute() getResp must beOk getResp.text must_== "Hello world!" } } }
87. Memento: NOTES CONTROLLERTEST class NotesControllerEndToEndTest extends Specification with NotesControllerDriver with ResponseMatchers { ! "Notes controller" should { "add a note and then successfully get it" in { ! val addResp = anAddNoteRequest.withText("Hello world!").execute() addResp must beOk addResp.noteId must not beEmpty ! val getResp = aGetNoteRequest.withId(addResp.noteId).execute() getResp must beOk getResp.text must_== "Hello world!" } } } trait ResponseMatchers extends Matchers { private implicit def intToIntMatcher(t: Int): Matcher[Int] = beEqualTo(t) ! def beOk = haveStatus(200) def beBadRequest = haveStatus(400) def beNotFound = haveStatus(404) ! def haveStatus(status: Matcher[Int]): Matcher[Response] = ((_: Response).status) ^^ status }
88. Memento: NOTES CONTROLLERTEST class NotesControllerEndToEndTest extends Specification with NotesControllerDriver with ResponseMatchers { ! "Notes controller" should { "add a note and then successfully get it" in { ! val addResp = anAddNoteRequest.withText("Hello world!").execute() addResp must beOk addResp.noteId must not beEmpty ! val getResp = aGetNoteRequest.withId(addResp.noteId).execute() getResp must beOk getResp.text must_== "Hello world!" } } }
89. LOAD BALANCER HAPROXY REVERSE PROXY NGINX APP SERVER FINATRA DATASTORE ELASTICSEARCH TRANSLATION SERVICE YANDEX
90. LOAD BALANCER HAPROXY REVERSE PROXY NGINX APP SERVER FINATRA DATASTORE ELASTICSEARCH TRANSLATION SERVICE YANDEX
91. TESTING EXTERNAL SERVICES
92. As always, LIFE IS ABOUT COMPROMISES AND SETTING BOUNDARIES
93. As always, LIFE IS ABOUT COMPROMISES AND SETTING BOUNDARIES => USE FAKES
94. FAKES FOR Avoid making external network calls in tests Create Fakes based on available documentation Fakes should have minimal implementation to only support testing Test the Fake against the real service in a contract test that’s manually run USE EXTERNAL SERVICES NOT EASILY AVAILABLE(Sometimes called Simplicators)
95. class NotesControllerEndToEndTest extends Specification with NotesControllerDriver with ResponseMatchers { ! private val port = 9921 private val server = new FakeYandexTranslateServer(port) ! step { server.start() } ! "Notes controller" should { "add a note and then get it translated" in { ... val translated = aTranslateRequest.withId(noteId).withLang("es").execute() translated must beOk translated.text must_== "Buenos días" } } ! step { server.stop() } }
96. class NotesControllerEndToEndTest extends Specification with NotesControllerDriver with ResponseMatchers { ! private val port = 9921 private val server = new FakeYandexTranslateServer(port) ! step { server.start() } ! "Notes controller" should { "add a note and then get it translated" in { ... val translated = aTranslateRequest.withId(noteId).withLang("es").execute() translated must beOk translated.text must_== "Buenos días" } } ! step { server.stop() } } class FakeYandexTranslateServer(port: Int) extends SimpleHttpServer(port) { ! private val json = """{ |"code": 200, |"lang": "en-es", |"text": ["Buenos días"] |} """.stripMargin ! override protected def onSimpleRequest(request: HttpRequest): String = json }
97. LOAD BALANCER HAPROXY REVERSE PROXY NGINX APP SERVER FINATRA DATASTORE ELASTICSEARCH TRANSLATION SERVICE YANDEX
98. LOAD BALANCER HAPROXY REVERSE PROXY NGINX APP SERVER FINATRA DATASTORE ELASTICSEARCH TRANSLATION SERVICE YANDEX
99. WHAT YOU SHOULD DO NEXT
100. CONTINUE FROM HERE How to CHECK OUT THE EXAMPLE github.com/orrsella/scala-e2e-testing ! END-TO-END TEST NEW PROJECTS It is easier to get started with e2e tests on a new project, integrating into an existing one is harder ! READ Growing Object-Oriented Software Guided by Tests
101. CONTINUE FROM HERE How to CHECK OUT THE EXAMPLE github.com/orrsella/scala-e2e-testing ! END-TO-END TEST NEW PROJECTS It is easier to get started with e2e tests on a new project, integrating into an existing one is harder ! READ Growing Object-Oriented Software Guided by Tests
102. THANK YOU