How to reduce duplication in your GitHub Actions workflows

<p>Recently ReactJS v18 was released. I started to look into its improvements, and checked which of my projects could benefit from them.</p><p>The main react-based project I maintain at the moment of writing this article is <a target="_blank" rel="noopener noreferrer" href="https://github.com/shlinkio/shlink-web-client">shlink-web-client</a>, so I naturally created a new branch and started the process.</p><p>The update was quite smooth, as most of the other dependencies I was using from the react ecosystem were already updated to support v18. All but one, <a target="_blank" rel="noopener noreferrer" href="https://enzymejs.github.io/enzyme/">enzyme</a>, the testing framework I was using to unit-test react components.</p><p>To be precise, I was able to continue running my tests, but some of them (those using <code>mount</code> instead of <code>shallow</code>) were still rendering components with the &quot;old&quot; React v17 approach, causing them to behave as in that version and a warning being printed in the console.</p><h3>First fix attempt</h3><p>The way enzyme integrates with the react version you are using is through an adapter library. The last official one supports only React v16, but someone released an <a target="_blank" rel="noopener noreferrer" href="https://github.com/wojtekmaj/enzyme-adapter-react-17">unofficial adapter for v17</a> which, with close to 650k weekly downloads, quickly became the way to go.</p><p>I checked if there was one for React 18, but sadly there wasn&#x27;t.</p><p>Also, the author of the adapter for v17 posted an article indicating <a target="_blank" rel="noopener noreferrer" href="https://dev.to/wojtekmaj/enzyme-is-dead-now-what-ekl">enzyme is dead</a>, he was not going to release one for v18, and publishing one for v17 was a mistake.</p><p>With those facts in mind, I started to face what was probably going to be the moment to migrate to <a target="_blank" rel="noopener noreferrer" href="https://testing-library.com/docs/react-testing-library/intro">react testing library</a>.</p><h3>Migration strategy</h3><p>I decided to follow a migration strategy similar to the one suggested in the article above, but with a couple of modifications:</p><ul><li>I update to React 18 anyway, as tests still pass.</li><li>Migrate right away all tests using <code>mount</code>, as those are the ones behaving differently.</li><li>New tests should be written directly with react testing library (RTL from now on).</li><li>When an existing test needs to be changed, consider migrating it to RTL, and do it if there&#x27;s time.</li><li>Introduce some PR from time to time just migrating a handful of tests.</li><li>Once everything is migrated, get rid of everything related with enzyme.</li></ul><h3>First contact and impressions</h3><p>I was a bit sceptical with RTL, as it was focused more on integration tests, instead of unit tests, which meant I had to completely change the mindset to write tests.</p><p>It also didn&#x27;t support shallow rendering, meaning that you will end up sometimes rendering a bigger component tree when testing container-like components, potentially causing side effects that could affect your test.</p><p>On the other hand there&#x27;s more and more people stating that <a target="_blank" rel="noopener noreferrer" href="https://kentcdodds.com/blog/why-i-never-use-shallow-rendering">shallow rendering is an anti-pattern</a>, and that&#x27;s probably the reason of enzyme getting &quot;discontinued&quot;.</p><p>Also, RTL has become the <a target="_blank" rel="noopener noreferrer" href="https://reactjs.org/docs/testing.html#tools">officially recommended framework</a> to test react components, it has become very popular, and it has even joined a wider group of testing libraries under the <a target="_blank" rel="noopener noreferrer" href="https://testing-library.com/"><code>@testing-library</code></a> organization.</p><p>The thing is that I started to use it, and I was quickly surprised with how it felt to work with it, and all the benefits it was bringing to my tests.</p><h3>Benefits I have experienced</h3><p>Once I started migrating the first tests I noticed some benefits:</p><ul><li>Changing my mindset was actually easier than I thought. The docs are very well written, so it&#x27;s relatively easy to start using RTL.</li><li>My tests got simpler, and required less of those nasty global mocks that jest allows (I&#x27;m looking at you, <a target="_blank" rel="noopener noreferrer" href="https://jestjs.io/es-ES/docs/mock-functions#mocking-modules"><code>jest.mock</code></a>).</li><li>Tests were way less coupled with implementation details. I moved from testing the component props, to test what the user would see on the screen.</li><li>Related with previous point, I started to write my tests by looking at the screen instead of the component&#x27;s implementation.</li><li>Changes in source code led to fewer tests requiring to be changed.</li><li>A progressive migration was possible, where some tests still use enzyme and others are already using RTL.</li></ul><p>And overall, it felt good and I have already dedicated a couple of PRs just to migrate more tests.</p><h3>Challenges I faced</h3><p>But of course, migrating to a new tool always comes with its own challenges, and this was not an exception. I&#x27;ll explain the main ones I have faced so far and how I tackled them:</p><ul><li><p>RTL lets you do some things in a couple of different ways, and the docs may not be super clear about what&#x27;s the recommended option.</p><p>For this I recommend reading <a target="_blank" rel="noopener noreferrer" href="https://acel.me/DCMb1">this article</a> from Kent C. Dodds, RTL&#x27;s author, which explains some common mistakes when using the library.</p></li><li><p>At first, I struggled a bit with asynchronous side effects and state changes in components, which can easily end up printing a warning like <code>Warning: An update to MyComponent inside a test was not wrapped in act</code>.</p><p>The warning also explains how you are supposed to solve this by wrapping your code in <code>act()</code>, but this warning comes from React, not RTL, and what it is not telling you is that RTL already wraps all needed operations in <code>act()</code>.</p><p>What this error usually mean is that you are not waiting for something to happen. <a target="_blank" rel="noopener noreferrer" href="https://acel.me/jnUdT">This other article</a>, also from Kent C. Dodds, explains everything you need to know about the things that can lead to this warning, and how to solve them.</p></li><li><p>Since you start testing from the user point of view, some use cases can be challenging to test without coupling with implementation details. For example, when you have a component which dynamically renders different images or icons, I used to directly check the component properties.</p><p>For this I found the best solution was to use <a target="_blank" rel="noopener noreferrer" href="https://jestjs.io/docs/snapshot-testing">jest snapshots</a>. I didn&#x27;t want to manually check which SVG was being rendered in the DOM, just that different ones were being used in every case.</p><pre><pre><code class="language-tsx">// I went from this...
test(&#x27;...&#x27;, () =&gt; {
  const wrapper = shallow(&lt;MyComp dynamicValue=&quot;foo&quot; /&gt;);
  expect(wrapper.find(FontAwesomeIcon).prop(&#x27;icon&#x27;)).toEqual(someIcon);
})

// To this
test(&#x27;...&#x27;, () =&gt; {
  const { container } = render(&lt;MyComp dynamicValue=&quot;foo&quot; /&gt;);
  expect(container.firstChild).toMatchSnapshot();
})
</code></pre></pre></li><li><p>Something very similar happens if you use some library that renders canvas. There&#x27;s no way to test that from a DOM point of view, which is what RTL does.</p><p>In my case I was using <a target="_blank" rel="noopener noreferrer" href="https://www.chartjs.org/">Chart.js</a> to render some charts, so I used <a target="_blank" rel="noopener noreferrer" href="https://github.com/hustcc/jest-canvas-mock">jest-canvas-mock</a>, which exposes a method on the canvas to see which are all the events invoked from the library.</p><p>Then I used snapshots again to verify they had the expected &quot;shape&quot;.</p><pre><pre><code class="language-tsx">// I went from this...
test(&#x27;...&#x27;, () =&gt; {
  const wrapper = shallow(&lt;MyCompWithCanvas /&gt;);
  expect(wrapper.find(Chart).prop(&#x27;data&#x27;).datasets).toEqual(...);
})

// To this
test(&#x27;...&#x27;, () =&gt; {
  const { container } = render(&lt;MyCompWithCanvas /&gt;);
  const events = container.querySelector(&#x27;canvas&#x27;)?.getContext(&#x27;2d&#x27;)?.__getEvents();

  expect(events).toBeTruthy();
  expect(events).toMatchSnapshot();
})
</code></pre></pre></li></ul><h3>Conclusion</h3><p>For better or worst, enzyme should no longer be considered an option. If you are starting a new project or are using it on small ones, consider migrating to RTL as soon as possible.</p><p>If you are using it in bigger projects, following the process described in this article will probably help you.</p><p>In any case, you will get surprised. React testing library is a great tool and provides many benefits over enzyme.</p><p>Its main issue is that it&#x27;s not a drop-in replacement for enzyme, so you will have to change a bit your mindset.</p>

My experience migrating from enzyme to react testing library

<p>Capturing code coverage for a test suite is a very useful way to know which parts of your source code are actually getting executed by tests.</p><p>This is useful not only to know if you need to add more tests to your project (in case the coverage is too low), but also, if you want to apply technics like mutation testing, having a properly generated code coverage report will dramatically speed up te execution and help you know if a non-killed mutant is relevant.</p><h3>Generating the code coverage</h3><p>Capturing code coverage is usually easy in the most common types of tests, like unit tests, where the source code is executed in the same process.</p><p>Tools like <a target="_blank" rel="noopener noreferrer" href="https://phpunit.de/">PHPUnit</a>, one of the most extended PHP testing frameworks, ships with tools like <a target="_blank" rel="noopener noreferrer" href="https://github.com/sebastianbergmann/php-code-coverage">php-code-coverage</a>, designed to capture the code under execution, just by providing a couple of lines of configuration.</p><p>However, generating a reliable code coverage report is not always that easy for other types of tests.</p><p>In contexts like E2E tests, where you may spin-up an API on a different process, and make your tests just call this API via HTTP and assert on the responses, PHPUnit will not be able to capture the code coverage, because the source code is actually being loaded on a different process.</p><h3>Remote code coverage</h3><p>A couple of weeks ago, I faced the issue described above. I had a web service for which I had a decent API test suite, but I wanted to capture code coverage for two main reasons:</p><ul><li>Be able to merge this coverage with the one generated by other tests suites, to know what&#x27;s the &quot;total&quot; code coverage, regardless the test producing it.</li><li>Apply mutation testing to the API tests, as I was already doing that for the rest of the test suites in the project. For this, I also needed to know exactly what tests were covering every line of the source code.</li></ul><p>After some investigation, I couldn&#x27;t find a built-in feature, where PHPUnit itself was able to &quot;remotely&quot; capture te code under test, so I had to think on a way to manually use <code>php-code-coverage</code> by myself.</p><h3>Code coverage reports</h3><p>In order to be able to capture code coverage, I had to make sure the instances of the objects provided by <code>php-code-coverage</code> where &quot;spin-up&quot; with the server, and then, the code coverage report was dumped at the end.</p><p>Also, you usually define the code to include/exclude from coverage in PHPUnit&#x27;s config, but since this time we are the ones creating the coverage objects, this was not possible.</p><p>I tried a couple of different approaches (more on this at the end), but the most accurate one for me, was to define two routes in my server, that were dynamically configured only when running the server in the context of these tests, and were responsible for creating and dumping the code coverage.</p><pre><pre><code class="language-php">use PHPUnit\Runner\Version;
use SebastianBergmann\CodeCoverage\CodeCoverage;
use SebastianBergmann\CodeCoverage\Driver\Selector;
use SebastianBergmann\CodeCoverage\Filter;
use SebastianBergmann\CodeCoverage\Report\Html\Facade as Html;
use SebastianBergmann\CodeCoverage\Report\PHP;
use SebastianBergmann\CodeCoverage\Report\Xml\Facade as Xml;

// Define directories containing the code you want to cover
$filter = new Filter();
$filter-&gt;includeDirectory(...);
$filter-&gt;includeDirectory(...);
$coverage = new CodeCoverage((new Selector())-&gt;forLineCoverage($filter), $filter);

// This is &quot;pseudo-code&quot;. Defining the routes depends on the framework you use
$app-&gt;get(&#x27;/api-tests/start-coverage&#x27;, function () use (&amp;$coverage) {
    $coverage-&gt;start(&#x27;API tests&#x27;);
    return new EmptyResponse();
});
$app-&gt;get(&#x27;/api-tests/stop-coverage&#x27;, function () use (&amp;$coverage) {
    $basePath = &#x27;...&#x27;; // Wherever you want the reports to be dumped
    $coverage-&gt;stop();

    // I generated coverage reports in a couple of different formats
    (new PHP())-&gt;process($coverage, $basePath . &#x27;/coverage.cov&#x27;);
    (new Xml(Version::getVersionString()))-&gt;process($coverage, $basePath . &#x27;/coverage-xml&#x27;);
    (new Html())-&gt;process($coverage, $basePath . &#x27;/coverage-html&#x27;);

    return new EmptyResponse();
});
</code></pre></pre><p>Then, I added the next snippet to my PHPUnit <code>bootstrap.php</code> file, to make sure the endpoints configured above are invoked at the proper times:</p><pre><pre><code class="language-php">// when starting up the test suite, call the endpoint to start collecting coverage
$httpClient-&gt;request(&#x27;GET&#x27;, &#x27;http://localhost:8080/api-tests/start-coverage&#x27;);

// When the tests process shuts down, call the endpoint to stop the coverage
register_shutdown_function(function () use ($httpClient): void {
    $httpClient-&gt;request(&#x27;GET&#x27;, &#x27;http://localhost:8080/api-tests/stop-coverage&#x27;);
});
</code></pre></pre><blockquote><p>Learn more about how to configure PHPUnit&#x27;s <a target="_blank" rel="noopener noreferrer" href="https://phpunit.readthedocs.io/en/9.5/configuration.html#the-bootstrap-attribute">bootstrap script</a>.</p></blockquote><p>This was fine from a pure code coverage point of view, but if you try it yourself, you will notice the report says all the code has been covered by <code>API tests</code>, which is what we provide when calling <code>$coverage-&gt;start(&#x27;API tests&#x27;);</code></p><p><img src="/assets/img/remote-coverage/invalid-api-coverage.png" alt="Invalid API coverage"/></p><p>To properly do mutation testing we need to know which are the exact tests that cover every part of the code. That requirement took me to the next approach.</p><h3>Supporting mutation testing</h3><p>To be more precise with the generated reports, I needed some way to notify the server about the specific test performing the request.</p><p>One way to do this is by sending a custom header when performing a request from your tests, and registering some event handler or middleware which starts the coverage for that request with the value coming from that header.</p><p>With that, I evolved the configuration above, and added a middleware handler (the framework I use is <a target="_blank" rel="noopener noreferrer" href="https://www.php-fig.org/psr/psr-15/">PSR-15</a> based, but the framework of your choice will probably have a way to do this).</p><pre><pre><code class="language-php">use ...

$coverage = new CodeCoverage();

// This ensures the coverage is started and stopped on every request, using the &quot;x-coverage-id&quot; header as the ID.
$app-&gt;middleware(function (ServerRequestInterface $req, RequestHandlerInterface $handler) use (&amp;$coverage) {
$coverage?-&gt;start(&#x27;API Tests&#x27;);
    $coverage-&gt;start($req-&gt;getHeaderLine(&#x27;x-coverage-id&#x27;));

    try {
        return $handler-&gt;handle($req);
    } finally {
        $coverage-&gt;stop();
    }
});

// This route is no longer needed. You can also remove the request from your bootstrap script
// $app-&gt;get(&#x27;/api-tests/start-coverage&#x27;, ...);
$app-&gt;get(&#x27;/api-tests/stop-coverage&#x27;, ...);
</code></pre></pre><p>Then, inside your test you can do something like this:</p><pre><pre><code class="language-php">use PHPUnit\Framework\TestCase;

class MyApiTest extends TestCase
{
    private ClientInterface $httpClient;

    public function setUp(): void
    {
        $this-&gt;httpClient = ...;
    }

    public function testMyEndpoint(): void
    {
        $resp = $this-&gt;httpClient-&gt;request(&#x27;POST&#x27;, &#x27;...&#x27;, [
            &#x27;headers&#x27; =&gt; [
                &#x27;x-coverage-id&#x27; =&gt; static::class,
            ],
        ])

        // Asserts go here...
    }
}
</code></pre></pre><p>After this, the code coverage reports will properly show the actual tests covering them.</p><p><img src="/assets/img/remote-coverage/valid-api-coverage.png" alt="Valid API coverage"/></p><h3>Alternative approach</h3><p>The approach explained here is functional, but it&#x27;s a bit hacky. I had to do it like this because of limitations with how I serve the API with <a target="_blank" rel="noopener noreferrer" href="https://openswoole.com">openswoole</a>.</p><p>However, instead of defining routes that need to be actively called to start/stop the code coverage (or just to dump the report, as in the second approach), you could try to register the shutdown function directly in the server side.</p><p>If that works for you, it&#x27;s much more straightforward, and you won&#x27;t need to bother changing your tests bootstrap script.</p><h3>Conclusion</h3><p>Even though there&#x27;s room for improvement, this allows to generate code coverage reports for code that&#x27;s running on a different process.</p><p>I plan to apply something similar for E2E tests for a command line app, so maybe I extend this article at some point.</p><p>Also, I decided to write this article, because at the moment of having to implement this myself, I didn&#x27;t find too much useful information out there.</p><p>I hope this helped you, and now you can collect code coverage reports on your API tests.</p>

Capturing remote code coverage in API tests with PHPUnit

<p>In the last couple of days I have been playing around with the idea of combining GitHub Actions and GitHub Pages to be able to dynamically build preview environments every time a pull request is opened against a repository hosting a client-side web app.</p><p>The idea is that you can quickly preview the changes made by some contributor, without having to clone their branch and running everything locally, something specially useful for open source projects.</p><p>In this article I will explain how to set everything up, and what are some considerations and problems you may face during the process.</p><h3>Enable github pages</h3><p>The first thing you need to do is enable your project to publish pages on some branch. I recommend creating a new branch for this, let&#x27;s say <code>preview-env</code>, and then enabling publishing on it.</p><p>In order to do that go to your repository and then <strong>Settings</strong> -&gt; <strong>Pages</strong>, look for the <strong>Source</strong> section, and you should see something like this:</p><p><img src="/assets/img/preview-envs/github-pages-before-enabling.png" alt="GitHub pages before enabling"/></p><p>Click in the dropdown and select your new branch, <code>preview-env</code>. Then click <strong>Save</strong>.</p><p><img src="/assets/img/preview-envs/github-pages-after-enabling.png" alt="GitHub pages after enabling"/></p><p>After saving you will see a message at the top of this section telling you what&#x27;s the URL in which the pages are published. It always follows the same pattern. If your organization is <code>my-org</code> and your repository is <code>my-repo</code>, the url will be <code>https://my-org.github.io/my-repo/</code>.</p><h3>Configure the workflow</h3><p>Now we need to configure a workflow that will &quot;deploy&quot; the preview environment for the branch every time a new pull request is created or updated:</p><p>Let&#x27;s imagine we have a React web app that is built with node.js. The configuration could look like this.</p><pre><pre><code class="language-yml"># .github/workflows/deploy-preview.yml
name: Deploy preview

on:
  pull_request: null

jobs:
  deploy:
    runs-on: ubuntu-20.04
    continue-on-error: true
    steps:
      - name: Checkout code
        uses: actions/checkout@v2
      - name: Use node.js 14.15
        uses: actions/setup-node@v1
        with:
          node-version: 14.15
      - name: Generate slug
        id: generate_slug
        run: echo &quot;##[set-output name=slug;]$(echo ${GITHUB_HEAD_REF#refs/heads/} | sed -r &#x27;s/[~\^]+//g&#x27; | sed -r &#x27;s/[^a-zA-Z0-9]+/-/g&#x27; | sed -r &#x27;s/^-+\|-+$//g&#x27; | tr A-Z a-z)&quot;
      - name: Build
        run: npm ci &amp;&amp; npm run build
      - name: Deploy
        uses: JamesIves/github-pages-deploy-action@4.1.1
        with:
          branch: preview-env
          folder: build
          target-folder: ${{ steps.generate_slug.outputs.slug }}
      - name: Publish env
        uses: marocchino/sticky-pull-request-comment@v2
        with:
          header: Preview environment
          message: |
            ## Preview environment
            https://my-org.github.io/my-repo/${{ steps.generate_slug.outputs.slug }}/
</code></pre></pre><blockquote><p>If you are not familiar with GitHub Actions yet, take a look at the <a target="_blank" rel="noopener noreferrer" href="https://docs.github.com/en/actions">official documentation</a>.</p></blockquote><p>This workflow will follow the next steps:</p><ul><li>Checkout the code from the repository.</li><li>Set-up node.js 14.15</li><li>Based on the branch name, generate a slug that we will use to have separated deployment folders for every pull request we receive. The slug is exposed to next steps as an output.</li><li>Build the project. This step will obviously depend on the needs of your project.</li><li>Using <a target="_blank" rel="noopener noreferrer" href="https://github.com/JamesIves/github-pages-deploy-action">JamesIves/github-pages-deploy-action</a>, deploy the contents we previously built in the GitHub page, under a sub-folder matching the slug we generated a few steps above, and under the branch <code>preview-env</code> (remember we enabled GitHub pages for this branch).</li><li>Finally, using <a target="_blank" rel="noopener noreferrer" href="https://github.com/marocchino/sticky-pull-request-comment">marocchino/sticky-pull-request-comment</a>, post a comment in the pull request with a link to the preview environment, so that you can just click on it and see the deployment.</li></ul><p>The steps may change depending on your needs and how you build your project. For example, I have an extra step to update a property in the <code>package.json</code> that is then used to allow serving the app in a sub-path instead of the root of the domain.</p><p>You may also not build your site with node.js, as you could be using any of the multiple existing static site generators out there, but you get the idea.</p><p>Finally, you have probably noticed the config includes <code>continue-on-error: true</code>. This will allow the pull request to be merged even if this process fails for some reason.</p><h3>Considerations when using forks</h3><p>While the configuration above will work perfectly when creating pull requests inside the same repository, there are some limitations when the pull request comes from a fork (which is the usual in OSS projects).</p><p>For security reasons, the <code>GITHUB_TOKEN</code> injected in those cases doesn&#x27;t have write permissions, which will make the &quot;deploy&quot; step fail.</p><p>Also, you cannot define your own token with more permissions and inject it as a secret, as the secrets are not exposed to workflows running on forks.</p><p>However, with a couple small config changes, we can work around these limitations:</p><h4>Change event</h4><p>The first thing we need to do is use the <code>pull_request_target</code> event instead of the <code>pull_request</code> one.</p><pre><pre><code class="language-diff">on:
-  pull_request: null
+  pull_request_target: null
</code></pre></pre><p>According to the documentation, this is equivalent to the <code>pull_request</code> event, but it runs in the scope of the base repository.</p><p>Thanks to this, the <code>GITHUB_TOKEN</code> will come with write permissions, and we will have access to secrets if needed.</p><h4>Checkout the fork</h4><p>The second thing we are going to change is that we now need to specify the repository to checkout.</p><p>In order to do that, we need to add two inputs to the &quot;Checkout code&quot; step, like this:</p><pre><pre><code class="language-diff">    steps:
      - name: Checkout code
        uses: actions/checkout@v2
+       with:
+         repository: ${{ github.event.pull_request.head.repo.full_name }}
+         ref: ${{ github.event.pull_request.head.ref }}
</code></pre></pre><p>This will ensure we checkout from the fork repository, instead of the base one, which is the default, as it&#x27;s the one where the <code>pull_request_target</code> event is scoped to.</p><p>And that&#x27;s it. With these two changes you can now deploy preview environments for pull requests coming from forks.</p><blockquote><p><strong>IMPORTANT!</strong> The limitations of the <code>pull_request</code> event are there for a reason. People could potentially get access to your secrets or manipulate your code. Proceed at your own risk.</p></blockquote><h3>Other considerations</h3><p>Other than the limitations for forks, there are a few other minor things to take into consideration.</p><ul><li>Changes in GitHub Pages do not reflect immediately. It may take up to a couple of minutes for the deployment to be available, but considering you will usually not review a PR right after it has been created, this should not be a big issue.</li><li>As you have seen, every time a pull request is created, the deployment will generate a new folder in your GitHub Pages branch. This may result in a lot of old folders to pile-up, so you may want to set up some way to clean them up periodically or after the pull request has been merged.</li><li>Due to the fact that GitHub Pages only allows static pages to be served, this process cannot be used with apps that require some kind of back-end or server-side logic.</li><li>If your project is already using GitHub Pages for something else (serve the project&#x27;s website or docs), that may conflict with this, preventing you from having this kind of preview envs.</li></ul>

Setting-up a preview environment for your client-side apps with GitHub Actions and GitHub Pages

<p>I remember many years ago, when I released my first open source project, that every time I had a new release ready, I was never sure what should be the new version number.</p><p>Versioning software is not as straightforward as it might look when you don&#x27;t have a lot of experience.</p><p>In this article I&#x27;ll try to explain the <a target="_blank" rel="noopener noreferrer" href="https://semver.org/">SemVer</a> approach to version software, and some things you might want to take into account on top of that.</p><h3>Semantic Versioning</h3><p>The first thing you need is a solid set of rules that help you decide which should your next version be.</p><p>I remember thinking <em>&quot;is this version big enough as to jump from 1.0 to 2.0?&quot;</em> or <em>&quot;I have seen projects using three numbers for the version, X.Y.Z, should I do the same?&quot;</em></p><p>Those questions are easier to answer if you stick to some standard that tells you what to do, and that will help others more easily understand your intention.</p><p>My recommendation is to use <a target="_blank" rel="noopener noreferrer" href="https://semver.org/">Semantic Versioning</a>, as it defines a solid starting point, and it&#x27;s quite adopted by the community.</p><p>Semantic Versioning states that you should use three numbers to identify versions, <code>MAJOR.MINOR.PATCH</code>, and follow these rules in order to decide which one to increase:</p><ul><li><code>PATCH</code>: the new release includes only bug fixes. People are encouraged to update to this release and no changes are needed in their code bases.</li><li><code>MINOR</code>: the new release includes new backwards-compatible features. People can update to this version without changing their code bases, and make use of the new features afterwards if they wish.</li><li><code>MAJOR</code>: the new release includes <a target="_blank" rel="noopener noreferrer" href="https://en.wikipedia.org/wiki/Backward_compatibility">backward compatibility</a> breaks. Changes in the code base will be needed when updating to this version.</li></ul><blockquote><p>These rules are easier to apply to libraries and frameworks than it is for apps and services. More about this later.</p></blockquote><h3>Try to keep backwards-compatibility</h3><p>Ok, we have some rules now. However, I have seen very frequently people mistaking what <em>can</em> be done with what <em>should</em> be done.</p><p>Yes, if you introduce a breaking change, you can update the major version and that&#x27;s it. However, if you do it too frequently, people won&#x27;t be happy, and you will end up with a fragmented user base, that stop updating to newer versions.</p><p>I remember using a library to deploy stuff that had a new major version every couple of months, changing things like &quot;The <code>host</code> function is now called <code>server</code>&quot;. Yes, ok, but why do I have to change my stuff so frequently.</p><p>It&#x27;s usually better to try to implement things in a backwards-compatible way, and keep track of the things you want to change and do it all at a time.</p><p>You can also deprecate things, and document the way you want those things to be done moving forward. That way you give people the chance to start changing their code and simplify a hypothetical upcoming major release.</p><h3>Provide clear upgrade paths</h3><p>As mentioned above, too frequent major version changes are not desirable, but sooner or later you will want to release a new major version for different reasons.</p><ul><li>Getting rid of that feature which is hard to maintain, introduces lots of bugs, and provides little value.</li><li>Supporting something new which is very hard to implement without breaking backwards compatibility.</li><li>Removing all those deprecated methods you have been dragging for months.</li><li>Fix design issues, where something was architected in the wrong way, and only spotted after some time.</li></ul><p>At the time this happens you will want your users to upgrade to the newer version, as you don&#x27;t want people to report bugs that only affect older versions, or to expect you to backport fixes to older versions because they haven&#x27;t updated to the new one.</p><p>The best way to achieve this is to provide clear and simple upgrade paths:</p><ul><li><p>Prepare your releases for the things to come: If you want to introduce new ways of doing things, do it before the major release, and deprecate the older ones. For example, you can have a new method that gets called by an older one, while you mark the old one as deprecated.</p><p>People will be more willing to update and change their code afterwards. By the time the major release is published, their code will be ready to upgrade.</p></li><li><p>Include a CHANGELOG file in your project, explaining the changes introduced in every version. A very good way to document a change log is the <a target="_blank" rel="noopener noreferrer" href="https://keepachangelog.com/">Keep a changelog</a> initiative.</p><p>You can also use some other platform to document the change log, like GitHub releases.</p></li><li><p>Include documentation on how to upgrade to a major release: This is probably the most important one. Document all the steps that need to be followed and all the required changes to update from a release to the next major one.</p><p>A good way to do this is by including an UPGRADE file in your project. You can see <a target="_blank" rel="noopener noreferrer" href="https://github.com/acmailer/acmailer/blob/main/UPGRADE.md">this example</a>.</p></li></ul><h3>Versioning libraries vs apps</h3><p>Semantic Versioning is a good standard to version software, but it plays much better with libraries and frameworks that are installed using some kind of package manager, than it does with apps and services that are not directly depended on.</p><p>For example, how do you identify a backward compatibility break on a web user interface?</p><p>With this kind of software there are more grey areas, and you will end up using your intuition.</p><p>For example, not long ago I released a <a href="/2020/12/24/released-shlink-web-client-v3-0-0/">new major version</a> for a web app I maintain, and it was completely compatible with the previous one. However, it introduced a larger amount of features than usual, and big UI changes, so I decided it was worth the bump.</p><p>Because of this there are projects that use different approaches to version apps. For example:</p><ul><li>Firefox and Chrome have 6-week cycles, and after each one of them they release a new major version no matter what.</li><li>Jetbrains publishes a few releases of their IDEs every year (I think 3) which always start with the year they were released on, like <code>2020.3.0</code>, and they increase the patch number for bugfixes.</li><li>Ubuntu releases 2 versions every year, one in April and one in October, and they are always identified by the year and month they were released on, like <code>19.04</code> or <code>20.10</code>.</li></ul><h3>Special versions</h3><p>There&#x27;s also a set of special versions that can be used to publish the so-called <strong>pre-release</strong> versions. These <a target="_blank" rel="noopener noreferrer" href="https://semver.org/#spec-item-9">are covered</a> by Semantic Versioning, but sometimes they are not so easy to understand.</p><p>It is also very likely that you never have to use these, as only relatively big projects will need this level of granularity, but it&#x27;s still good to know what&#x27;s their purpose and what do they imply.</p><h4>0.x.y</h4><p>It is possible to release a version of your software where the major number is <code>0</code>. When this happens, it means your software is still in its early stages.</p><p>It does not mean it&#x27;s necessarily unstable, but it means you are still introducing frequent changes on it, and therefore, it might be a bit more fragile than a version starting with a number greater than <code>0</code>.</p><h4>Alpha</h4><p>The intention of an alpha release is that a subset of people con test some new functionality, but you don&#x27;t want people to use it in production</p><p>Alpha versions are on their very early stages. Their public API is very likely to change, and they probably contain bugs.</p><p>Semantic Versioning states that alpha versions are identified by this pattern: <code>MAJOR.MINOR.PATCH-alpha.NUMBER</code>, for example <code>2.0.0-alpha.1</code>.</p><h4>Beta</h4><p>Similar to alpha versions, beta versions are also prone to contain bugs, but their API will in theory not change. That means that you could potentially adapt your software to start using a beta version, and when the corresponding stable release is published, you shouldn&#x27;t need that many changes.</p><p>Semantic Versioning defines a pattern similar to the one for alpha versions: <code>MAJOR.MINOR.PATCH-beta.NUMBER</code>, for example <code>2.0.0-beta.1</code>.</p><h4>Release candidate</h4><p>Release candidates (RC) are pre-release versions that you will want to publish for the general user-base to test an upcoming release. You want to publish a RC so that it&#x27;s battle tested by as many people as possible, in order to find possible bugs and edge cases.</p><p>They should not contain many bugs, but some could be found. The public API should not change anymore.</p><p>According to Semantic Versioning, the pattern to identify a RC is <code>MAJOR.MINOR.PATCH-rc.NUMBER</code>, for example <code>2.0.0-rc.1</code>.</p><h3>Conclusion</h3><p>We have seen some approaches and considerations to properly version your software.</p><p>Versioning is not so straightforward when you don&#x27;t have a lot of experience, but as you have seen, you just need to know a small set of rules and use a bit your intuition.</p><p>With those tools, you will be able to properly version your software.</p>

What to take into account when versioning software

<p>Let&#x27;s not deny that <a target="_blank" rel="noopener noreferrer" href="https://github.com/features/actions">GitHub actions</a> are hitting hard in the tech community, and many projects are transitioning from other continuous integration systems like <a target="_blank" rel="noopener noreferrer" href="https://circleci.com/">Circle CI</a> or <a target="_blank" rel="noopener noreferrer" href="https://travis-ci.org/">Travis CI</a>.</p><p>Personally I have been using Travis a lot during the past years, for all my OSS projects, and I have gotten very used to it.</p><p>However, people seem to be &quot;abandoning&quot; travis in favor of GitHub Actions, for different reasons. &quot;It&#x27;s faster&quot;, &quot;I can run smaller tasks in parallel&quot;, etc.</p><p>In my case, I have moved a few very specific tasks there, where travis was becoming a bottleneck, but I still have mixed feelings about the very-verbose yaml-based config needed to configure a few GitHub Actions, compared to the more concise travis one.</p><p>In this article I&#x27;ll explain how I improved a travis build to run several smaller tasks in parallel jobs, without having to completely move away from it.</p><h3>Initial state</h3><p>This project&#x27;s travis config is relatively simple. It is used to build a JS project for the web browser, and it has to run the next tasks:</p><ul><li>Lint the code, to make sure it fulfils the project&#x27;s coding standards.</li><li>Run unit tests.</li><li>Run mutation tests.</li><li>Build the docker image, to make sure none of the new changes broke it.</li><li>Conditionally publish a release on GitHub, with a dist file attached to it, if the build is being run for a git tag.</li></ul><pre><pre><code class="language-yaml">dist: bionic

language: node_js

branches:
  only:
    - /.*/

cache:
  directories:
    - node_modules

services:
  - docker

node_js:
  - &#x27;12.16.3&#x27;

install: npm ci

before_script:
  - echo &quot;Building commit range ${TRAVIS_COMMIT_RANGE}&quot;
  - export MUTATION_FILES=$(git diff ${TRAVIS_COMMIT_RANGE:-origin/main} --name-only | grep -E &#x27;src\/(.*).(ts|tsx)$&#x27; | paste -sd &quot;,&quot;)

script:
  - npm run lint
  - npm run test:ci
  - npm run mutate:ci
  - docker build -t project:test .

after_success:
  - node_modules/.bin/ocular coverage/clover.xml

before_deploy: npm run build ${TRAVIS_TAG#?}

deploy:
  - provider: releases
    api_key:
      secure: &lt;key&gt;
    file: &quot;./dist/project_${TRAVIS_TAG#?}_dist.zip&quot;
    skip_cleanup: true
    on:
      tags: true
</code></pre></pre><h3>Problems with this approach</h3><p>This is more or less ok, but the last two commands in <code>script</code> can be relatively slow and can delay the whole process.</p><p>Also, specially the mutation tests one, which is currently always considered successful regardless the result, can make the build reach the maximum run time allowed by travis, making the whole build falsely fail.</p><blockquote><p>The reason for the <code>before_script</code> step is to determine which source code files changed, and run mutation tests on them only, in order to mitigate this.</p></blockquote><p>Other than this, the build config defines &quot;global&quot; customizations that are actually only used for some tasks:</p><ul><li>Running <code>npm ci</code> is not required for the <code>docker build</code> task.</li><li>Getting the <code>docker</code> service is not required by any of the other tasks.</li><li>Determining changed files is only used by the <code>mutation tests</code> task.</li></ul><h3>Making use of jobs</h3><p>One cool feature travis supports is the use of a job <a target="_blank" rel="noopener noreferrer" href="https://docs.travis-ci.com/user/build-matrix/">build matrix</a>, that lets you define multiple jobs that run in parallel as part of the same build, and make each one of them do unrelated tasks.</p><p>Using this feature it is possible to improve the <code>.travis.yml</code> file, making it look like this:</p><pre><pre><code class="language-yaml">dist: bionic

language: node_js

branches:
  only:
    - /.*/

cache:
  directories:
    - node_modules

node_js:
  - &#x27;12.16.3&#x27;

jobs:
  fast_finish: true
  allow_failures:
    - name: &#x27;Mutation tests&#x27;
  include:

    - name: &#x27;Lint&#x27;
      install: npm ci
      script: npm run lint

    - name: &#x27;Unit tests&#x27;
      install: npm ci
      script: npm run test:ci
      after_success:
        - node_modules/.bin/ocular coverage/clover.xml

    - name: &#x27;Mutation tests&#x27;
      install: npm ci
      before_script:
        - echo &quot;Building commit range ${TRAVIS_COMMIT_RANGE}&quot;
        - export MUTATION_FILES=$(git diff ${TRAVIS_COMMIT_RANGE:-origin/main} --name-only | grep -E &#x27;src\/(.*).(ts|tsx)$&#x27; | paste -sd &quot;,&quot;)
      script: npm run mutate:ci

    - name: &#x27;Build docker image&#x27;
      services:
        - docker
      install: skip
      script: docker build -t project:test .

    - name: &#x27;Publish release&#x27;
      if: tag IS present
      install: skip
      script: skip
      before_deploy: npm run build ${TRAVIS_TAG#?}
      deploy:
        - provider: releases
          api_key:
            secure: &lt;key&gt;
          file: &quot;./dist/project_${TRAVIS_TAG#?}_dist.zip&quot;
          skip_cleanup: true
          on:
            tags: true
</code></pre></pre><p>This approach introduces all these benefits:</p><ul><li>Now linting, testing, mutation testing and building the docker image run in parallel, making the build finish earlier.</li><li>The mutation testing step is allowed to fail, and thanks to the <code>fast_finish</code> flag, travis won&#x27;t even wait for it to finish, considering the build successful once the rest have passed.</li><li>Configs that are only meaningful for certain jobs are defined in the job itself, instead of globally.</li><li>The &quot;publish release&quot; job only runs conditionally if the build is for a tag, thanks to the <code>if: tag IS present</code> condition. (More info about <a target="_blank" rel="noopener noreferrer" href="https://docs.travis-ci.com/user/conditional-builds-stages-jobs/">conditional jobs</a> in travis).</li><li>As soon as any of the jobs fails, the whole build fails and you don&#x27;t have to continue waiting. Before this, if the third task failed, you still had to wait for the previous two to finish.</li><li>Each job can have a name, making it more clear in travis UI what tasks are being run:</li></ul><p><img src="/assets/img/travis-multiple-jobs/travis-jobs.png" alt="Travis CI jobs"/></p><h3>Conclusion</h3><p>The main purpose of this article was to showcase that travis still has a lot to give. Github Actions are definitely cool, but there&#x27;s usually no silver bullet for everything, and a combination with other tools might be more suitable.</p><p>Also, this allows people using travis to improve their builds without having to change everything. Then, once you have split your tasks, if you still want to move to Github Actions, it should be easier.</p><blockquote><p>If you are curious, this is the project in which I use this travis configuration: <a target="_blank" rel="noopener noreferrer" href="https://github.com/shlinkio/shlink-web-client">shlinkio/shlink-web-client</a>.</p></blockquote>

Running several steps of a Travis CI build in parallel

<p>I&#x27;ve been wanting to write this article for a while, but it is a subject complex to approach.</p><p>Lately I&#x27;ve had some &quot;conflicts&quot; with users in some of the open source software (OSS) projects I maintain, and I have also seen some of the people I follow on Twitter dealing with the same.</p><p>Because of that I wanted to share my point of view on what should be the attitude and considerations when using OSS.</p><h3>Company vs personal</h3><p>The first thing you have to take into account when using OSS, is that there are two kinds of projects which usually have different goals.</p><h4>Company projects</h4><p>It is very common that companies which activity is related with software or make a deep use of technology, publish their own OSS projects.</p><p>These projects are usually born from some need the company has had which is not strictly part of their domain.</p><p>Thanks to publishing these projects they can find new talent (among contributors), or position themselves in the industry.</p><p>It&#x27;s also quite common that companies provide paid services which are related with these OSS projects, like specific hostings or deployment services, or just consultancy on using them.</p><h4>Personal projects</h4><p>There&#x27;s also projects which are usually maintained by one person, or a very small team, during their own free time.</p><p>These projects are created by people who do it mainly because they love to program and want to share something they have done.</p><p>The goal here is to get some visibility, show some skills, learn something new and contribute to the open source community.</p><p>While the main purpose is not usually getting money, they frequently accept donations and sponsorships.</p><hr/><p>Now we know the two main groups of OSS projects. Sometimes we think they are the same, but company projects are usually maintained by people which is paid by a company, and do it during their working hours.</p><p>On the other hand, personal projects cannot get that much attention and resources, so they cannot progress as fast as the company ones.</p><h3>Considerations</h3><p>That said, when we want to use an open source project or contribute to it, there are a few things to take into account.</p><h4>Always be polite</h4><p>While using a project, you will probably end up finding something is not working as you expected, or you&#x27;ll develop a new need for which the project does not provide a solution.</p><p>When reporting bugs or asking for new features, always try to <strong>be polite</strong>. Provide as many details as possible, be descriptive and help maintainers reproduce the issue.</p><p>If you are asked to do some tests and get back with the result, try to find the time to do it. You may think that&#x27;s not your work, but the issue will get solved much earlier and you will avoid frustrations.</p><p>There&#x27;s a formula I like to use when reporting issues, which consists in filling this template:</p><ul><li>I did <em>[action]</em>.</li><li>I expected <em>[behavior]</em> to happen.</li><li>Instead <em>[other_behavior]</em> happened.</li></ul><p>This will simplify maintainers see the user&#x27;s intention, and detect confusions which are not actually bugs. Helping the user use the tool will be easier this way.</p><h4>Don&#x27;t take anything for granted</h4><p>Just because you open a ticket, does not mean the team is going to work on it right away. There are several reasons that could delay it.</p><ul><li>The project has other priorities.</li><li>It&#x27;s hard to reproduce.</li><li>There&#x27;s no one available to work on it.</li><li>Maintainers just want to spend their time in something else (specially in the case of personal projects).</li></ul><p>The people working in the project is usually dealing with a much wider scope than you might think, so you have to be patient and understand this.</p><p>It could also happen that they don&#x27;t really want to maintain what you proposed, even though it&#x27;s a supper critical feature for you, but a project will never be able to cover the 100% of use cases.</p><h4>Consider contributing</h4><p>One of the main principles of the open source philosophy is collaboration.</p><p>If you have been using an OSS project, the best way to show some appreciation and collaborate with its continuity is by contributing to it.</p><p>There are several ways to contribute.</p><ul><li>You could improve the documentation,</li><li>You could provide some PR fixing some bug or improving the code.</li><li>You could provide some PR with some new feature.</li><li>You could make some economic donation or sponsorship.</li></ul><p>The last one is very rare, specially among individual users, but if your company is taking advantage of an OSS project, you should consider it.</p><p>For the other three cases, if there&#x27;s something you think you can help with, there&#x27;s something to take into account in relation with previous point. You should <strong>always ask first</strong>.</p><p>Maybe someone is already working on something similar, or the team has some ideas in mind that could be shared before starting any implementation, or, as I said before, maybe they just don&#x27;t want to maintain it.</p><p>If you ask first you will save yourself some time and frustrations.</p><h4>Follow the project rules</h4><p>All projects have rules, and I&#x27;m talking about any kind of rule. How to write issues, the code of conduct, the coding standards, the amount of people that need to approve a PR before merging it...</p><p>You have to always follow these rules. Don&#x27;t try to enforce something just because you consider it better.</p><p>If the project requires the use of spaces for indentation but you used tabs because you like them better, don&#x27;t get mad if maintainers don&#x27;t want to merge your PR.</p><h4>Don&#x27;t take it personally</h4><p>And finally, because of the reasons exposed in previous points, there will be decisions you don&#x27;t like.</p><p>Don&#x27;t take it personally, because it&#x27;s not in most of the cases.</p><p>Your issue could be closed because you didn&#x27;t follow the issue template, or because they asked you to check something and you didn&#x27;t give any feedback after some days.</p><p>Understand this can happen, and you can always be polite and open a discussion, but never get mad and accuse the team to be unfair or treat you in the wrong way.</p><h3>Conclusion</h3><p>This article describes a set of rules that should help people using OSS projects and people maintaining them to understand each other, but focusing on the former.</p><p>I will try to write something similar but focusing on how maintainers should behave. We obviously forget some times that there&#x27;s people trusting on us when using the software we write.</p>

Alejandro Celaya | Blog

Software development, agile methodologies and open source projects.

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