Revert back to cache lock w/ firstOrCreate (#24)

While in a transaction upsert will lock the row until the transaction is
finished. Using a cache lock avoids this but also introduces a possible
duplicate exception in rare cases

Co-authored-by: Lucas Graciano <[email protected]>

src/ProcessStamp.php

@@ -59,21 +59,21 @@ public static function firstOrCreateByProcess(array $process, ?string $hash = nu
             $parent = static::firstOrCreateByProcess(static::getProcessName($process['type'], $process['parent_name']));
         }
 
-        // Workaround races with `firstOrCreate` by leveraging a no-change upsert.
-        // NOTE: Not using `insertOrIgnore` because of possible side-effects.
-        static::upsert(
-            [
-                [
-                    'hash'      => $hash,
+        $stamp = static::where('hash', $hash)->first();
+
+        /*
+         * If stamp does not exist in the database yet, go ahead and obtain a lock to create it.
+         * This specifically doesn't lock as the first step to avoid all calls obtaining a lock from the cache if the item already exists in the DB.
+         */
+        if (! $stamp) {
+            Cache::lock('process-stamps-hash-create-' . $hash, 10)->get(function () use (&$stamp, $hash, $process, $parent) {
+                $stamp = static::firstOrCreate(['hash' => $hash], [
                     'name'      => trim($process['name']),
                     'type'      => $process['type'],
                     'parent_id' => optional($parent)->getKey(),
-                ],
-            ],
-            ['hash'], // Should be unique to hash.
-            [] // Update nothing.
-        );
-        $stamp = static::where('hash', $hash)->first();
+                ]);
+            });
+        }
 
         return $stamp;
     }