RedHatTraining/rht-labs-docs.git

Adapt documentation for the new name convention for Cluster API and Routes

Marcos Entenza

2018-11-22 530a252602df82868700d9d835ebdef3cdacbc20

commit \| author \| age
92e460	1	# Revenge Of The Automated Testing
43f2f2	2
b5d705	3	> The purpose of this exercise is to develop and validate a new feature using TDD; and to promote the assured feature through the pipeline.
f6d2bd	4
62a054	5	![comic-header](../images/exercise3/comic-header.png)
RH	6
	7	[Image Source](https://cdn-images-1.medium.com/max/1600/1*wF_fSCH-gLYfMbkwb3gR2w.png)
	8
b76e74	9	## Introduction to TDD.
D	10
	11	> _Here is a brief introduction of TDD and why we use it._
	12
	13	Test Driven Development (TDD) is a software development process that relies on the repetition of a very short development cycle. Requirements are turned into test cases, where the software is developed to pass the tests. In other words, it creates a safety net that serves to keep the developer's problems/bugs at bay while enabling the developer to refactor efficiently. This is opposed to software development that allows software to be added that is not proven to meet requirements.
	14
	15	The TDD cycle can be illustrated with the following diagram;
	16	![TDD-diagram](../images/exercise3/TDD-lifecycle.jpg)
	17
1173e5	18	### The TDD Cycle
b76e74	19
D	20	1. `Write a test` -
e43fd2	21	In TDD a new feature begins by writing a test. Write a test that clearly defines a function or one that provides an improvement to an existing function. It's important the developer clearly understands the feature's specification and requirements, or the feature could be wrong from the get-go.
b76e74	22
D	23	2. `Test Fails` -
1173e5	24	When a test is first implemented it is expected to fail. This failure validates the test is working correctly as the feature is yet to be implemented.
b76e74	25
D	26	3. `Write code to make test pass` -
	27	This step involves implementing the feature to pass the failed test. Code written at this stage may be inelegant and still pass the test, however this is acceptable as TDD is a recursive cycle which includes code refactoring.
	28
	29	4. `Code Passes tests` -
	30	If all tests pass, the developer can be confident that the new code meets the test requirements.
	31
	32	5. `Refactor` -
82cb19	33	The refactoring step will allow the developer to clean up their code without changing its behaviour. Not changing the behaviour should ensure the tests still pass. The process of refactoring can include; removal of duplication, renaming of object, class, module, variable and method names to clearly represent their current purpose and use, decoupling of functionality and increasing code cohesion.
b76e74	34
D	35	6. `Repeat` -
	36	Starting with another new test, the cycle is then repeated to push forward the functionality. The size of the steps should always be small, with as few as 1 to 10 edits between each test run. If new code does not rapidly satisfy a new test, or other tests fail unexpectedly, the programmer should undo or revert in preference to excessive debugging.
	37
	38	### Testing Bananalogy
1173e5	39	Explanation of Mocha and JS test syntax through Bananalogy! Imagine for a moment; we're not building software but creating a bowl of fruit. To create a `Bunch of Bananas` component for our fruit bowl we could start with our tests as shown below.
b76e74	40	![bdd-bananas](../images/exercise3/bdd-bananas.png)
D	41	* `describe` is used to group tests together. The string `"a bunch of ripe bananas"` is for human reading and allows you to identify tests.
	42	* `it` is a statement that contains a test. It should contain an assertion such as `expect` or `should`. It follows the syntax of `describe` where the string passed in identifies the statement.
f6d2bd	43
D	44	---
43f2f2	45
D	46	## Learning Outcomes
f6d2bd	47
43f2f2	48	As a learner you will be able to
f6d2bd	49
5285f8	50	* Understand the why behind TDD
95ba2a	51	* Implement a feature using TDD for front end and backend
5285f8	52	* Write end to end tests for the feature and run them in CI
43f2f2	53
D	54	## Tools and Frameworks
f6d2bd	55
43f2f2	56	> Name of tool - short description and link to docs or website
D	57
5285f8	58	1. [Jest](https://facebook.github.io/jest/) - Zero configuration testing platform
D	59	Jest is used by Facebook to test all JavaScript code including React applications. One of Jest's philosophies is to provide an integrated "zero-configuration" experience. We observed that when engineers are provided with ready-to-use tools, they end up writing more tests, which in turn results in more stable and healthy code bases.
	60	1. [Vue Test Utils](https://vue-test-utils.vuejs.org/en/) - Vue Test Utils is the official unit testing utility library for Vue.js.
	61	1. [Nightwatch.js](http://nightwatchjs.org/) - Nightwatch.js is an easy to use Node.js based End-to-End (E2E) testing solution for browser based apps and websites. It uses the powerful W3C WebDriver API to perform commands and assertions on DOM elements.
	62	1. [Mocha](https://mochajs.org/) - Mocha is a feature-rich JavaScript test framework running on Node.js and in the browser, making asynchronous testing simple and fun. Mocha tests run serially, allowing for flexible and accurate reporting, while mapping uncaught exceptions to the correct test cases. Hosted on GitHub.
1173e5	63	1. [Sinon](http://sinonjs.org/) - Standalone test spies, stubs and mocks for JavaScript.
5285f8	64	Works with any unit testing framework.
43f2f2	65
D	66	## Big Picture
664135	67	> From the previous exercise; we created a simple pipeline. We will now flesh it out with some testing to add gates to our pathway to production.
f6d2bd	68
664135	69	![big-picture](../images/big-picture/big-picture-3.jpg)
43f2f2	70
f6d2bd	71	---
43f2f2	72
D	73	## 10,000 Ft View
	74
8894bf	75	> The goal of this exercise is to add a new component to the application using TDD to create and validate its behaviour. The User story we have been given is as follows:
43f2f2	76
1173e5	77	As a doer I want to mark todos as important so that I can keep track of and complete high priority todos first
f6d2bd	78
5285f8	79	_Acceptance Criteria_
D	80	- [ ] should be doable with a single click
	81	- [ ] should add a red flag against the todo when marked important
	82	- [ ] should remove the red colour flag on the flag when important removed
	83	- [ ] should not affect existing todos
	84
	85	_On page load:_
	86	- [ ] should display existing todos that are not marked important
	87	- [ ] should display existing todos that are marked important with an red flag
43f2f2	88
D	89	## Step by Step Instructions
91cc51	90	> This is a fairly structured guide with references to exact filenames and sections of text to be added.
43f2f2	91
f6d2bd	92	### Part 1 - Tests in our Pipeline
95ba2a	93	> _In this part we will get familiar with the layout of our tests. We will also improve the pipeline created already by adding some unit tests for the front end & backend along with some end to end tests (e2e) to validate the full solution_
43f2f2	94
d4f1fa	95	#### 1a - FE Unit tests
95ba2a	96	> In this exercise we will execute our test for the front end locally. Once verified we will add them to Jenkins.
bc2216	97
664135	98	1. Before linking our automated testing to the pipeline we'll first ensure the tests run locally. Change to the `todolist-fe` directory and run `test`.
91cc51	99	```bash
fad576	100	cd todolist-fe
D	101	```
	102	```bash
	103	npm run test
91cc51	104	```
1173e5	105	<p class="tip" >
60bca4	106	`test` is an alias used that runs `vue-cli-service test` from the scripts object in `package.json`
91cc51	107	</p>
b76e74	108	![screenshot-scripts](../images/exercise3/screenshot-scripts.png)
D	109
95ba2a	110	2. This command will run all `spec.js` files. Our test files are stored in the following places. There are 12 front end test files stored in these directories: `todolist-fe/tests/unit/vue-components/` & `todolist-fe/tests/unit/javascript/*`
bc2216	111
91cc51	112	2. You should see an output similar to the following. The above command has run a test suite for every `*.spec.js` file. The table generated in the terminal shows the code coverage. We're going to be focusing on the unit tests for now.
b76e74	113	![test-run-locally](../images/exercise3/test-run-locally.png)
91cc51	114
1173e5	115	2. Repeat the same process for `todolist-api` and verify that all the tests run. If you have an ExpressJS server already running from previous exercise; you should kill it before running the tests. The `mocha` test suite will launch a dev server for running the tests. There are 2 API test files: `todolist-api/server/api/todo/todo.spec.js` & `todolist-api/server/mocks/mock-routes.spec.js` for our API and the Mocks server.
91cc51	116	```bash
fad576	117	cd todolist-api
D	118	```
	119	```bash
	120	npm run test
91cc51	121	```
6e5072	122
530a25	123	2. Navigate to your instance of Jenkins at `https://jenkins-<YOUR_NAME>-ci-cd.<APPS_URL>`.
91cc51	124	Click on `dev-todolist-fe-build` and then click the `configure` button on the left-hand side.
b76e74	125	![jenkins-configure-job](../images/exercise3/jenkins-configure-job.png)
91cc51	126
449d67	127	2. Scroll to the `Build` part of the configuration page and add `npm run test` below `npm install`.
b76e74	128	![jenkins-build-step](../images/exercise3/jenkins-build-step.png)
91cc51	129
530bd4	130	2. Scroll to the `Post-build Actions` section and click `Add post-build action`. Select `Publish xUnit test result report` (Jenkins might place this at the top of the `Post-build Actions` list).
b76e74	131	![xunit-action](../images/exercise3/xunit-action.png)
6e5072	132
A	133	2. Click the `Add` button under `Publish xUnit test result report` and select `JUnit`. In the pattern field enter `test-report.xml`. In the `Failed Tests Thresholds` input box enter 0 under `Red Ball Total`. It should look a little something like this:
b76e74	134	![post-build-actions](../images/exercise3/post-build-actions.png)
6e5072	135
f56999	136	2. Click `save` or `apply` at the bottom to save the changes. Run the `dev-todolist-fe-build` job and verify that this passes and the `build` and `bake` jobs are both triggered.
6e5072	137
0d4d53	138	#### (Optional) Failing the tests
da5391	139	> _If you're not very confident in your technical ability and want don't want to do the TDD lab; feel free to just do this next section. If you are confident jump on to the e2e testing section below_
0d4d53	140
8eeb96	141	2. We're now going to deliberately fail a test to ensure that `bake` and `deploy` jobs aren't triggered if any tests fail. Open the `todolist-fe` source code in your favourite editor. Open `ListOfTodos.spec.js` in `/tests/unit/vue-components` and head to `line 39`. Add `not.` before `toHaveBeenCalled()` to fail the test.
b76e74	142	![change-test-to-fail](../images/exercise3/change-test-to-fail.png)
6e5072	143
f56999	144	2. Push this to Gitlab and run the build job.
6e5072	145	```bash
fad576	146	git add .
D	147	```
	148	```bash
	149	git commit -m "TEST - failing build with tests"
	150	```
	151	```bash
	152	git push
6e5072	153	```
A	154
1173e5	155	2. Rerun the `dev-todolist-fe-build` job. It should have failed and not run any other jobs.
b76e74	156	![jenkins-with-failing-build](../images/exercise3/jenkins-with-failing-build.png)
6e5072	157
a83842	158	2. You can examine the test results on the jobs home page. Drill down into the tests to see which failed and other useful stats
D	159	![fe-test-fails](../images/exercise3/fe-test-fails.png)
	160
2717b2	161	2. Undo the changes you made to the `ListOfTodos.spec.js` file, commit your code and rerun the build. This should trigger a full `build --> bake --> deploy` of `todolist-fe`.
530bd4	162
0d4d53	163	#### 1b - End to End tests (e2e)
3c8f9c	164	> _Unit tests are a great way to get immediate feedback as part of testing an application. End to end tests that drive user behaviour are another amazing way to ensure an application is behaving as expected._
bc2216	165
8529b9	166	In this exercise we will add a new stage to our pipeline called `dev-todolist-fe-e2e` that will run after the deploy has been completed. End to end tests will use Nightwatchjs to orchestrate a selenium webdriver instance that controls the web browser; in this case Chrome!
D	167
	168	2. Let's start by checking our tests execute locally. On the terminal move to the `todolist-fe` folder. Our end to end tests are stored in `tests/e2e/specs/`. The vuejs cli uses nightwatch and comes pre-configured to run tests against Chrome. We have created some additional configuration in the root of the project `nightwatch.config.js` to run headless in CI mode on Jenkins.
	169	```bash
fad576	170	cd todolist-fe
8529b9	171	```
D	172
	173	2. Run the tests locally by executing the following. This should start the dev server and run the test. You may see the browser pop up and close while tests execute.
	174	```bash
fad576	175	npm run e2e
8529b9	176	```
e0761f	177	![local-e2e](../images/exercise3/local-e2e.png)
8529b9	178
e0761f	179	2. With tests executing locally; let's add them to our Jenkins pipeline. To do this; we'll create a new job and connect it up to our `todolist-fe` jobs. Open Jenkins and create a `New Item` called `dev-todolist-fe-e2e`. Make this Job `Freestyle`.
8529b9	180
530bd4	181	2. On the configuration page (under the general tab); Set the Label for the job to run on as `jenkins-slave-npm`. Check the box marking the build parameterised and add a String parameter of `BUILD_TAG` as done before
e0761f	182	![e2e-general](../images/exercise3/e2e-general.png)
bc2216	183
e0761f	184	2. On the Source Code Management tab; set the source code to git and add the url to your `todolist-fe` app. Set the branch to `refs/tags/${BUILD_TAG}`
D	185	![e2e-git](../images/exercise3/e2e-git.png)
	186
530bd4	187	2. Set `Color ANSI Console Output` on the `Build Environment` section
e0761f	188
33c738	189	2. On the Build section; add a build step to execute shell and fill in the following substituting `<YOUR_NAME>` accordingly:
e0761f	190	```bash
530a25	191	export E2E_TEST_ROUTE=todolist-fe-<YOUR_NAME>-dev.<APPS_URL>
4acca2	192	npm install
D	193	npm run e2e:ci
e0761f	194	```
D	195	![e2e-steps](../images/exercise3/e2e-steps.png)
	196
530bd4	197	2. Add a Post Build action to `Publish Junit test result report`. Add `reports/e2e/specs/*.xml` to the report location and save the configuration to be brought back to the Job's homepage.
e0761f	198	![e2e-post-build](../images/exercise3/e2e-post-build.png)
D	199
530bd4	200	2. We want to connect the e2e job we just created to our dev pipleline by editing the post build actions on `dev-todolist-fe-deploy` job. Open the `dev-todolist-fe-deploy` job and hit `configure`. In the `Post-build actions` section of this job add a `Trigger parameterised build` on other jobs. Set the `Projects to build` to be `dev-todolist-fe-e2e`. Add a Parameter and set the it to the `Current build parameters`. Save the settings.
7f49cd	201	![e2e-trigger](../images/exercise3/e2e-trigger.png)
D	202
f52b28	203	2. Run the pipeline from the beginning to see the tests executed (two executions will show tests scores on the graph!).
bc2216	204
5285f8	205	### Part 2 - TodoList new feature
bc2216	206	> _In this exercise we will introduce a new feature to create an important flag on the todos. In order to be able to build and test our feature we will use TDD_
D	207
5285f8	208	As a doer I want to mark todos as important so that I can keep track of and complete high prirority todos first
bc2216	209
5285f8	210	_Acceptance Criteria_
D	211	- [ ] should be doable with a single click
	212	- [ ] should add a red flag against the todo when marked important
	213	- [ ] should remove the red colour flag on the flag when important removed
	214	- [ ] should not affect existing todos
bc2216	215
5285f8	216	_On page load:_
D	217	- [ ] should display existing todos that are not marked important
	218	- [ ] should display existing todos that are marked important with an red flag
bc2216	219
d4f1fa	220	#### 2a - Create todolist-api tests
5285f8	221	> Using [Mocha](https://mochajs.org/) as our test runner; we will now write some tests for backend functionality to persist our important-flag. The changes required to the backend are minimal but we will use TDD to create our test first, then implement the functionality.
f6d2bd	222
D	223	3. Create a new branch in your `todolist-api` app for our feature and push it to the remote
bc2216	224	```bash
fad576	225	git checkout -b feature/important-flag
D	226	```
	227	```bash
	228	git push -u origin feature/important-flag
43f2f2	229	```
D	230
f6d2bd	231	3. Navigate to the `server/api/todo/todo.spec.js` file. This contains all of the existing todo list api tests. These are broken down into simple `describe("api definition", function(){})` blocks which is BDD speak for how the component being tested should behave. Inside of each `it("should do something ", function(){})` statements we use some snappy language to illustrate the expected behaviour of the test. For example a `GET` request of the api is described and tested for the return to be of type Array as follows.
D	232	```javascript
	233	describe("GET /api/todos", function() {
	234	it("should respond with JSON array", function(done) {
	235	request(app)
	236	.get("/api/todos")
	237	.expect(200)
	238	.expect("Content-Type", /json/)
	239	.end(function(err, res) {
	240	if (err) return done(err);
	241	// Test goes here
	242	res.body.should.be.instanceof(Array);
	243	done();
	244	});
5285f8	245	});
f6d2bd	246	});
D	247	```
	248	where:
3c9a48	249	- `describe` is used to group tests together into a collection asserting some feature; for example the get all todos api.
D	250	- `it` is an individual test statement and should contain an `expect` or a `should` statement asserting behaviour of the API under test.
	251	- `request` is a library for making http calls to the api.
	252	- `.expect(200)` asserts the HTTP Return Code
	253	- `res.body.should.be.instanceof(Array);` is the actual test call
	254	- `done();` tells the test runner that `mocha` has finished execution. This is needed as the http calls are asynchronous.
43f2f2	255
1173e5	256	3. With this knowledge; let's implement our test for the `important` flag. We expect the front end to introduce a new property on each `todo` that gets passed to the backend called `important`. The API will need to handle this new property and pass it into the mongodb. Let's begin implementing this functionality by writing our test case. Navigate to the `PUT /api/todos` section of the `server/api/todo/todo.spec.js` test file (which should be at the bottom)
3c9a48	257	![todo-api-tests](../images/exercise3/todo-api-tests.png)
f6d2bd	258
3c9a48	259	3. Before writing our test; let's first make sure all the existing tests are passing.
5285f8	260	```bash
fad576	261	npm run test
f6d2bd	262	```
D	263
3c9a48	264	3. With all the tests passing; let's add our new one. For ease of completing this exercise a template of a new test has been written at the very end of the file (just below the ` // Exercise 3 test case!` comment). A PUT request responds in our API with the data that it has just updated. So provided that MongoDB accepted the change, the API will respond with an object that has the `important` property on it. To write our test; edit the template test by completing the following:
7fdd6e	265	* Edit the `it("should ...")` to describe the important flag we're testing
f6d2bd	266	* Edit the `.send()` to include `important: true` property
3c9a48	267	* Edit the `.expect()` to be `.expect(200)`
f6d2bd	268	* Add a new test assertion to check that `res.body.important` is `true` below the `// YOUR TEST GO HERE` line.
D	269	```javascript
3c9a48	270	// Exercise 3 test case!
5285f8	271	it("should mark todo as important and persist it", function(done) {
f6d2bd	272	request(app)
D	273	.put("/api/todos/" + todoId)
5285f8	274	.send({
D	275	title: "LOVE endpoint/server side testing!",
	276	completed: true,
	277	important: true
	278	})
f6d2bd	279	.expect(200)
D	280	.expect("Content-Type", /json/)
	281	.end(function(err, res) {
5285f8	282	if (err) return done(err);
D	283	res.body.should.have.property("_id");
	284	res.body.title.should.equal("LOVE endpoint/server side testing!");
	285	// YOUR TEST GO HERE
	286	res.body.important.should.equal(true);
	287	done();
f6d2bd	288	});
5285f8	289	});
f6d2bd	290	```
D	291
5285f8	292	3. Run your test. It should fail.
D	293	```bash
fad576	294	npm run test
f6d2bd	295	```
D	296	![fail-mocha](../images/exercise3/fail-mocha.png)
	297
7fdd6e	298	3. With our test now failing; let's implement the feature. This is quite a simple change - we first need to update the `server/api/todo/todo.model.js`. Add an additional property on the schema called `important` and make its type Boolean.
f6d2bd	299	```javascript
D	300	const TodoSchema = new Schema({
5285f8	301	title: String,
D	302	completed: Boolean,
	303	important: Boolean
f6d2bd	304	});
D	305	```
7fdd6e	306
1173e5	307	3. Next we need to update the `server/config/seed.js` file so that the pre-generated todos have an important property. Add `important: true` below `completed: ` for each object. Don't forget to add a comma at the end of the `completed: ` line.
7fdd6e	308	![api-add-seed-important](../images/exercise3/api-add-seed-important.png)
f6d2bd	309
5285f8	310	3. With your changes to the Database schema updated; re-run your tests.
D	311	```bash
fad576	312	npm run test
f6d2bd	313	```
D	314
5285f8	315	3. Commit your code to the `feature/important-flag` branch and then merge onto the `develop` branch as follows
f6d2bd	316	<p class="tip">
D	317	NOTE - At this point in a residency we would peer review the code before pushing it to develop or master branch!
	318	</p>
5285f8	319	```bash
fad576	320	git add .
D	321	```
	322	```bash
	323	git commit -m "ADD backend schema updates"
	324	```
	325	```bash
	326	git push
	327	```
	328	```bash
	329	git checkout develop
	330	```
	331	```bash
	332	git merge feature/important-flag
	333	```
	334	```bash
	335	git push
f6d2bd	336	```
D	337
44888e	338	3. After pushing your changes; start back up the `todolist-api` app on a new terminal session
D	339	```bash
fad576	340	npm run start
44888e	341	```
D	342
95ba2a	343	#### 2b - Create todolist-fe tests
1173e5	344	> Using [Jest](https://facebook.github.io/jest/) as our test runner and the `vue-test-utils` library for managing our vue components; we will now write some tests for front end functionality to persist our important-flag. The changes required to the front end are quite large but we will use TDD to create our test first, then implement the functionality.
f6d2bd	345
e43fd2	346	Our TodoList App uses `vuex` to manage the state of the app's todos and `axios` HTTP library to connect to the backend. `Vuex` is an opinionated framework for managing application state and has some key design features you will need to know to continue with the exercise.
f6d2bd	347
8894bf	348	In `vuex` the application state is managed by a `store`. The `store` houses all the todos we have retrieved from the backend as well as the `getter` methods for our array of `todos`. In order to make changes to the store, we could call the store directly and update each todo item but as earlier said; vuex is an opinionated module with its own way of updating the store. It is bad practice to call the store directly.
5285f8	349
e43fd2	350	There are two parts of the lifecycle to updating the store, the `actions` & `mutations`. When the user clicks a todo to mark it as complete; the `actions` are called. An action could involve a call to the backend or some pre-processing of the data. Once this is done, the change is committed to the store by calling the `mutation` function. A store should only ever be manipulated through a mutation function. Calling the mutation will then update the todo object in the app's local store for rendering in the view.
5285f8	351
D	352	For example; when marking a todo as done in the UI, the following flow occurs
44888e	353	* The `TodoItem.vue` calls the `markTodoDone()` function which dispatches an event to the store.
D	354	* This calls the `updateTodo()` function in the `actions.js` file
	355	* The action will update the backend db (calling our `todolist-api`) with our updated todo object.
	356	* The action will commit the change to the store by calling the mutation method `MARK_TODO_COMPLETED`
	357	* The `MARK_TODO_COMPLETED` will directly access the store object and update it with the new state value
	358	* The `ListOfTodos.vue` component is watching the store for changes and when something gets updated it re-renders the `TodoItem.vue`.
	359
	360	The implementation of our `important` flag will follow this same flow.
5285f8	361
D	362	3. Let's implement our feature by first creating a branch. Our new feature, important flag will behave in the same way as the `MARK_TODO_COMPLETED`. Create a new branch in your `todolist-fe` app for our feature and push it to the remote
f6d2bd	363	```bash
fad576	364	git checkout -b feature/important-flag
D	365	```
	366	```bash
	367	git push -u origin feature/important-flag
f6d2bd	368	```
bc2216	369
1173e5	370	3. Let's get our tests running by executing a `--watch` on our tests. This will keep re-running our tests everytime there is a file change. It is handy to have this running in a new terminal session.
5285f8	371	```bash
fad576	372	npm run test -- --watch
5285f8	373	```
D	374
44888e	375	3. All the tests should be passing when we begin. If `No tests found related to files changed since last commit` is on show; hit `a` on the terminal to re-run `all` tests.
D	376	![rerun-all](../images/exercise3/rerun-all.png)
	377
b5d705	378	3. There are three places we will add new tests to validate our function behaves as expected against the acceptance criteria from the Feature Story supplied to us. We will need to write tests for our `TodoItem.vue` to handle having a red flag and that it is clickable. Our app is going to need to persist the changes in the backend so we'll want to make changes to our `actions.js` and `mutations.js` to keep the api and local copy of the store in sync. Let's start with our `TodoItem.vue` component. Open the `tests/unit/vue-components/TodoItem.spec.js` file. This has been templated with some example test to correspond with our A/Cs for speed of doing the exercise. Find the describe block for our important flag tests. It is setup already with a `beforeEach()` hook for test setup.
5285f8	379	![important-flag-before](../images/exercise3/important-flag-before.png)
D	380
8894bf	381	3. Each of our test cases has its skeleton in place already for example the `TodoItem.vue` component takes a property of `todos` when rendering. This setup is already done for each of our tests so all we have to do is fill in our assertions.
5285f8	382	![todoitem-skeleton-tests](../images/exercise3/todoitem-skeleton-tests.png)
D	383
44888e	384	3. Let's implement the first test `it("should render a button with important flag"`. This test will assert if the button is present on the page and it contains the `.important-flag` CSS class. To implement this; add the `expect` statement as follows below the `// TODO - test goes here!` comment.
5285f8	385	```javascript
D	386	it("should render a button with important flag", () => {
	387	const wrapper = mount(TodoItem, {
	388	propsData: { todoItem: importantTodo }
	389	});
	390	// TODO - test goes here!
	391	expect(wrapper.find(".important-flag").exists()).toBe(true);
	392	});
	393	```
	394
	395	3. Save the file and we should see in our test watch the test case has started failing because we have not yet implemented the feature!
	396	![todoitem-fail-test](../images/exercise3/todoitem-fail-test.png)
	397
7fdd6e	398	3. With a basic assertion in place, let's continue on to the next few tests. We want the important flag to be red when an item in the todolist is marked accordingly. Conversely we want it to be not red when false. Let's create a check for `.red-flag` CSS property to be present when important is true and not when false. Complete the `expect` statements in your test file as shown below for both tests.
5285f8	399	```javascript
D	400	it("should set the colour to red when true", () => {
	401	const wrapper = mount(TodoItem, {
	402	propsData: { todoItem: importantTodo }
	403	});
	404	// TODO - test goes here!
	405	expect(wrapper.find(".red-flag").exists()).toBe(true);
	406	});
	407	it("should set the colour to not red when false", () => {
	408	importantTodo.important = false;
	409	const wrapper = mount(TodoItem, {
	410	propsData: { todoItem: importantTodo }
	411	});
	412	// TODO - test goes here!
	413	expect(wrapper.find(".red-flag").exists()).toBe(false);
	414	});
	415	```
	416
baa8d9	417	3. Finally, we want to make the flag clickable and for it to call a function to update the state. The final test in the `TodoItem.spec.js` we want to create should simulate this behaviour. Implement the `it("call markImportant when clicked", () ` test by first simulating the click of our important-flag and asserting the function `markImportant()` to write is executed.
5285f8	418	```javascript
baa8d9	419	it("call markImportant when clicked", () => {
5285f8	420	const wrapper = mount(TodoItem, {
D	421	methods,
	422	propsData: { todoItem: importantTodo }
	423	});
	424	// TODO - test goes here!
	425	const input = wrapper.find(".important-flag");
	426	input.trigger("click");
	427	expect(methods.markImportant).toHaveBeenCalled();
	428	});
	429	```
	430
44888e	431	3. With our tests written for the feature's UI component, let's implement our code to pass the tests. Explore the `src/components/TodoItem.vue`. Each vue file is broken down into 3 sections
5285f8	432	* The `<template></template>` contains the HTML of our component. This could include references to other Components also
D	433	* The `<script></script>` contains the JavaScript of our component and is essentially the logic for our component. It defines things like `properties`, `methods` and other `components`
	434	* The `<style></style>` contains the encapsulated CSS of our component
44888e	435
e43fd2	436	3. Underneath the `</md-list-item>` tag, let's add a new md-button. Add an `.important-flag` class on the `md-button` and put the svg of the flag provided inside it.
5285f8	437	```html
D	438	</md-list-item>
b5d705	439	<!-- TODO - SVG for use in Exercise3 -->
5285f8	440	<md-button class="important-flag">
D	441	<svg height="24" viewBox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg" ><path d="M0 0h24v24H0z" fill="none"/><path d="M14.4 6L14 4H5v17h2v-7h5.6l.4 2h7V6z"/></svg>
	442	</md-button>
	443	```
	444
	445	3. We should now see the first of our failing tests has started to pass. Running the app locally (using `npm run serve`) should show the flag appear in the UI. It is clickable but won't fire any events and the colour is not red as per our requirement. Let's continue to implement the colour change for the flag. On our `<svg/>` tag, add some logic to bind the css to the property of a `todo.important` by adding ` :class="{'red-flag': todoItem.important}" `. This logic will apply the CSS class when `todo.important` is true.
	446	```html
	447	<md-button class="important-flag">
	448	<svg :class="{'red-flag': todoItem.important}" height="24" viewBox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg" ><path d="M0 0h24v24H0z" fill="none"/><path d="M14.4 6L14 4H5v17h2v-7h5.6l.4 2h7V6z"/></svg>
	449	</md-button>
	450	```
	451
e43fd2	452	3. More tests should now be passing. Let's wire the click of the flag to an event in Javascript. In the methods section of the `<script></script>` tags in the Vue file, implement the `markImportant()`. We want to wire this to the action to updateTodo, just like we have in the `markCompleted()` call above it. We also need to pass an additional property to this method called `important`
5285f8	453	```javascript
D	454	markImportant() {
b5d705	455	// TODO - FILL THIS OUT IN THE EXERCISE
5285f8	456	this.$store.dispatch("updateTodo", {id: this.todoItem._id, important: true});
D	457	console.info("INFO - Mark todo as important ", this.todoItem.important);
	458	},
	459	```
	460
e43fd2	461	3. Let's connect the click button in the DOM to the Javascript function we've just created. In the template, add a click handler to the md-button to call the function `markImportant()` by adding ` @click="markImportant()"` to the `<md-button>` tag
5285f8	462	```html
b5d705	463	<!-- TODO - SVG for use in Exercise3 -->
5285f8	464	<md-button class="important-flag" @click="markImportant()">
D	465	<svg :class="{'red-flag': todoItem.important}" height="24" viewBox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg" ><path d="M0 0h24v24H0z" fill="none"/><path d="M14.4 6L14 4H5v17h2v-7h5.6l.4 2h7V6z"/></svg>
	466	</md-button>
	467	```
7fdd6e	468
A	469	3. Finally - we need to make it so that when a new todo item is created it will have an important property. Head to `store/actions.js` and add `important: false` below `completed: false` in the `addTodo(){}` action.
	470	![fe-add-actions-important](../images/exercise3/fe-add-actions-important.png)
	471
5285f8	472
1173e5	473	3. The previously failing tests should have started to pass now. With this work done, let's commit our code. On the terminal, run
5285f8	474	```bash
fad576	475	git add .
D	476	```
	477	```bash
	478	git commit -m "Implementing the todoitem flag"
	479	```
	480	```bash
	481	git push
5285f8	482	```
D	483
f34abc	484	3. Open our local todolist app (http://localhost:8080/#/todo). If we try to use our important flag, we should see it's still not behaving as expected; this is because we're not updating the state of the app in response to the click event.
D	485
	486	3. We need to implement the `actions` and `mutations` for our feature. Let's start with the tests. Open the `tests/unit/javascript/actions.spec.js` and navigate to the bottom of the file. Our action should should commit the `MARK_TODO_IMPORTANT` to the mutations. Scroll to the end of the test file and implement the skeleton test by adding `expect(commit.firstCall.args[0]).toBe("MARK_TODO_IMPORTANT");` as the assertion.
5285f8	487	```javascript
D	488	it("should call MARK_TODO_IMPORTANT", done => {
	489	const commit = sinon.spy();
	490	state.todos = todos;
	491	actions.updateTodo({ commit, state }, { id: 1, important: true }).then(() => {
	492	// TODO - test goes here!
	493	expect(commit.firstCall.args[0]).toBe("MARK_TODO_IMPORTANT");
	494	done();
	495	});
	496	});
	497	```
	498
bc581a	499	3. We should now have more failing tests, let's fix this by adding the call from our action to the mutation method. Open the `src/store/actions.js` file and scroll to the bottom to the `updateTodo()` method. Complete the if block by adding `commit("MARK_TODO_IMPORTANT", i);` as shown below.
5285f8	500	```javascript
D	501	updateTodo({ commit, state }, { id, important }) {
	502	let i = state.todos.findIndex(todo => todo._id === id);
	503	if (important) {
7fdd6e	504	// TODO - add commit important here!
5285f8	505	commit("MARK_TODO_IMPORTANT", i);
D	506	} else {
	507	commit("MARK_TODO_COMPLETED", i);
	508	}
	509	```
	510
e43fd2	511	3. Finally, let's implement the `mutation` for our feature. Again, starting with the tests... Open the `tests/unit/javascript/mutations.spec.js` to find our skeleton tests at the bottom of the file. Our mutation method is responsible for toggling the todo's `important` property between `true` and `false`. Let's implement the tests for this functionality by setting important to be true and calling the method expecting the inverse. Then let's set it to false and call the method expecting the inverse. Add the expectations below the `// TODO - test goes here!` comment as done previously.
5285f8	512	```javascript
D	513	it("it should MARK_TODO_IMPORTANT as false", () => {
	514	state.todos = importantTodos;
	515	// TODO - test goes here!
	516	mutations.MARK_TODO_IMPORTANT(state, 0);
	517	expect(state.todos[0].important).toBe(false);
	518	});
	519
	520	it("it should MARK_TODO_IMPORTANT as true", () => {
	521	state.todos = importantTodos;
	522	// TODO - test goes here!
	523	state.todos[0].important = false;
	524	mutations.MARK_TODO_IMPORTANT(state, 0);
	525	expect(state.todos[0].important).toBe(true);
	526	});
	527	```
	528
530bd4	529	3. With our tests running and failing, let's implement the feature to their spec. Open the `src/store/mutations.js` and add another function called `MARK_TODO_IMPORTANT` below the `MARK_TODO_COMPLETED` to toggle `todo.important` between true and false. NOTE - add a `,` at the end of the `MARK_TODO_COMPLETED(){}` function call.
5285f8	530	```javascript
D	531	MARK_TODO_IMPORTANT(state, index) {
	532	console.log("INFO - MARK_TODO_IMPORTANT");
	533	state.todos[index].important = !state.todos[index].important;
	534	}
	535	```
f34abc	536	![mark-todo-important](../images/exercise3/mark-todo-important.png)
5285f8	537
530bd4	538	3. All our tests should now be passing. On the watch tab where they are running, hit `a` to re-run all tests and update any snapshots with `u` if needed.
5285f8	539
D	540	3. With all our tests now passing, let's commit our code. On the terminal, run
	541	```bash
fad576	542	git add .
D	543	```
	544	```bash
	545	git commit -m "Implementing the store and actions"
	546	```
	547	```bash
	548	git push
5285f8	549	```
D	550
70ba2a	551	3. Before running a build in Jenkins, let's add our tests and code to the develop branch. Ask your neighbour to review your code changes and if they approve; merge them to Develop! (If you're feeling adventurous - raise a PR through GitLab and have someone on your desk peer review it!)
5285f8	552	<p class="tip">
D	553	NOTE - At this point in a residency we would peer review the code before pushing it to develop or master branch!
	554	</p>
	555	```bash
fad576	556	git checkout develop
D	557	```
	558	```bash
	559	git merge feature/important-flag
	560	```
	561	```bash
	562	git push --all
5285f8	563	```
D	564
f34abc	565	3. Run a build in Jenkins. If all things were successful; our application should be deployed as expected! Validate the flag is working as expected.
D	566	![todolist-important](../images/exercise3/todolist-important.png)
bc2216	567
d4f1fa	568	#### 2c - Create todolist e2e tests
bc2216	569
51f8a9	570	> Using [Nightwatch.js](http://nightwatchjs.org/) We will write a reasonably simple e2e test to test the functionality of the feature we just implemented.
6b43e4	571
T	572	3. Firstly we need to create an e2e spec test file in the correct place.
	573
	574	```bash
	575	touch tests/e2e/specs/importantFlag.js
	576	```
	577
	578	3. Open this new file in your code editor and set out the initial blank template for an e2e test as below:
	579	![if-e2e-step1](../images/exercise3/if-e2e-step1.png)
	580
	581	3. Now get the test to access the todos page and wait for it to load. The url can be taken from `process.env.VUE_DEV_SERVER_URL`
	582	![if-e2e-step2](../images/exercise3/if-e2e-step2.png)
	583
	584	3. Now click the clear all button and then enter a value in the textbox to create a new item. We clear all first to ensure we start with a fresh list. We now do our first assertion: that a 'important flag' exists (the button to set important), and also that a red flag does not exist. You will quickly find there is no way to reference the clear all button. We will therefore have to go to `src/components/XofYItems.vue` and add `id="clear-all"` to the clear all button.
	585	![if-e2e-step3](../images/exercise3/if-e2e-step3.png)
	586	![if-e2e-step3a](../images/exercise3/if-e2e-step3a.png)
	587
	588	3. We should now get nightwatch to click the flag and check whether the flag has turned red.
	589	![if-e2e-step4](../images/exercise3/if-e2e-step4.png)
	590
	591	3. At this point we should have a working e2e test. We can run this by using `npm run e2e`. When satisfied we can push up these changes.
	592
	593	```bash
	594	git add .
	595	```
	596
	597	```bash
	598	git commit -m "Implementing e2e tests"
	599	```
	600
	601	```bash
	602	git push
	603	```
43f2f2	604
f6d2bd	605	---
43f2f2	606
D	607	## Extension Tasks
f6d2bd	608
43f2f2	609	> _Ideas for go-getters. Advanced topic for doers to get on with if they finish early. These will usually not have a solution and are provided for additional scope._
D	610
3c8f9c	611	* Add Config maps to inject DB creds to the app
D	612	* Create a blue/green deploy based on the success of running e2e tests against either blue or green and flopping load over to new endpoint when successful.
	613	Advanced
	614	* Add Auth0 support to your FE app.
43f2f2	615
D	616	## Additional Reading
f6d2bd	617
43f2f2	618	> List of links or other reading that might be of use / reference for the exercise
D	619
	620	## Slide links
f6d2bd	621
01c4da	622	- [Intro](https://docs.google.com/presentation/d/18W0GoBTwRGpgbOyHf2ZnL_OIWU_DvsoR14H0_t5jisA)
RH	623	- [Wrap-up](https://docs.google.com/presentation/d/1uIYHC57POSaVD6XNZGhdetABiSnlP1TztYTgglMP-DA)
1173e5	624	- [All Material](https://drive.google.com/drive/folders/1xVaQukmwwmyJSDN0zOkghZX7yb-0freT)