Fastly Soft Purge

+++ b/acquia_purge.routing.yml
@@ -0,0 +1,7 @@
+    _permission: 'Enable/Disable Soft Purge in Fastly'

🤔 This is a really weird permission name.

It doesn't follow the pattern of Drupal core's permissions.

+++ b/src/AcquiaPlatformCdn/FastlyBackend.php
@@ -241,11 +241,19 @@ class FastlyBackend extends BackendBase implements BackendInterface {
+    $soft_purge = \Drupal::config('acquia_purge.soft_purge')->get('acquia_purge_soft_purge');

Should be injected.

+++ b/src/AcquiaPlatformCdn/FastlyBackend.php
@@ -241,11 +241,19 @@ class FastlyBackend extends BackendBase implements BackendInterface {
+	if($soft_purge) {
+	  \Drupal::logger('fastly')->notice('Soft purging fastly caches');
+	  $opt['headers']['Fastly-Soft-Purge'] = 1;
+	}
+
+	return $opt;

🐛 Leading tabs instead spaces.

+++ b/src/Form/SoftPurgeConfigForm.php
@@ -0,0 +1,88 @@
+namespace Drupal\acquia_purge\Form;
+use Drupal\Core\Form\ConfigFormBase;

🤓 Needs extra \n in between.

+++ b/src/Form/SoftPurgeConfigForm.php
@@ -0,0 +1,88 @@
+ * Configure logging behavior.

🐛 Copy/pasted stale comment.

+++ b/src/Form/SoftPurgeConfigForm.php
@@ -0,0 +1,88 @@
+  final public function __construct() {

🤔 Why final?

Why even have a constructor if there is nothing in there?

+++ b/src/Form/SoftPurgeConfigForm.php
@@ -0,0 +1,88 @@
+      '#prefix' => '<p>',
+      '#suffix' => '</p>',
+      '#markup' => $this->t("Fastly provides a Soft Purge feature that allows you to mark content as outdated (stale) instead of permanently purging and thereby deleting it from Fastly's caches. Objects invalidated with Soft Purge will be treated as outdated (stale) while Fastly fetches a new version from origin. For more information visit <a href='https://docs.fastly.com/en/guides/soft-purges'>https://docs.fastly.com/en/guides/soft-purges</a>"),

Huh? Why not:

'#markup' => '<p>'. $this->t(…) .'</p>'

?

+++ b/src/Form/SoftPurgeConfigForm.php
@@ -0,0 +1,88 @@
+    $config = $this->config('acquia_purge.soft_purge');
+    $soft_purge = $config->get('acquia_purge_soft_purge');

🤔

So … the config is

acquia_purge.soft_purge.acquia_purge_soft_purge

?

That looks very very weird.

+++ b/src/Form/SoftPurgeConfigForm.php
@@ -0,0 +1,88 @@
+    $form['acquia_purge_soft_purge'] = array(

🤔 So … this is mixing old style PHP array syntax in with the new? Let's make this look sane.

+++ b/src/Form/SoftPurgeConfigForm.php
@@ -0,0 +1,88 @@
+      '#title' => $this
+        ->t('Enable Fastly Soft Purge'),

🐛 Poorly placed line break.

+++ b/src/Form/SoftPurgeConfigForm.php
@@ -0,0 +1,88 @@
+    $messenger = \Drupal::messenger();

🐛

First: this should've been injected.

Second: this is already available to you thanks to the base class!

+++ b/src/Form/SoftPurgeConfigForm.php
@@ -0,0 +1,88 @@
+      $messenger->addMessage('Fastly soft purge enabled', $messenger::TYPE_WARNING);

🤔 Why not use addWarning()?

+++ b/src/Form/SoftPurgeConfigForm.php
@@ -0,0 +1,88 @@
+    $this->config('acquia_purge.soft_purge')
+      ->set('acquia_purge_soft_purge', $enabled)

🐛

$enabled is not guaranteed to be a boolean.

And … config schema is missing.