Add daily email for 06/04/25

source/_daily_emails/2025-04-06.md

@@ -0,0 +1,71 @@
+---
+title: Caching with decorators
+date: 2025-04-06
+permalink: daily/2025/04/06/caching
+tags:
+  - software-development
+  - drupal
+  - php
+cta: ~
+snippet: |
+  TODO
+---
+
+As well as [working with different versions of an API][0], I was able to use the same technique I wrote about yesterday to easily add a cacheable version of the API client.
+
+As they all implement the same `ApiClientInterface`, I can inject and decorate a client with another client, making one solely responsible for caching the result from the API whilst keeping the API interaction logic separate (aka [the Decorator design pattern][1]).
+
+Here's an example based on the code I wrote:
+
+```php
+final class CacheableApiClient implements ApiClientInterface {
+
+  /**
+   * The cache duration in seconds.
+   */
+  private const CACHE_DURATION = 3600;
+
+  public function __construct(
+    private readonly ApiClientInterface $client,
+    private readonly TimeInterface $time,
+    private readonly CacheBackendInterface $cache,
+  ) {
+  }
+
+  public function getResults(): Collection {
+    $key = $this->getCacheKey();
+
+    $cache = $this->cache->get($key);
+
+    if ($cache !== FALSE) {
+      return $cache->data;
+    }
+
+    $result = $this->client->getResults();
+
+    $this->cache->set(
+      cid: $key,
+      data: $result,
+      expire: $this->time->getRequestTime() + self::CACHE_DURATION,
+    );
+
+    return $result;
+  }
+
+}
+```
+
+Nothing in this instance is specific to either version of the API.
+
+This client is only concerned with retrieving and saving cache data, and delegating any other logic to the original version.
+
+With this approach, I can switch between `V1ApiClient`, `V2ApiClient` or any other version with the same methods without having to reimplement caching as that's handled within the `CacheableApiClient`.
+
+But what if I don't want to interact with the API at all?
+
+For local development, I have a `FakeApiClient` that returns a static response that I can work with.
+
+The possibilities are endless.
+
+[0]: {{site.url}}/daily/2025/04/05/strategies
+[1]: {{site.url}}/daily/2022/12/08/the-decorator-design-pattern