Create NamespacedStore to prefix lock resources from symfony/lock

CHANGELOG.md

@@ -4,6 +4,23 @@ All notable changes to this project will be documented in this file.
 
 The format is based on [Keep a Changelog](https://keepachangelog.com), and this project adheres to [Semantic Versioning](https://semver.org).
 
+## [Unreleased]
+### Added
+* Add a `NamespaceStore` class that can be used to wrap `symfony/lock` stores and prefix key resources.
+
+### Changed
+* *Nothing*
+
+### Deprecated
+* *Nothing*
+
+### Removed
+* *Nothing*
+
+### Fixed
+* *Nothing*
+
+
 ## [5.5.1] - 2023-05-28
 ### Added
 * *Nothing*

README.md

@@ -403,3 +403,4 @@ $helper->publishUpdate(Update::forTopicAndPayload('some_queue', ['foo' => 'bar']
 * `Paginator`: An object extending `Pagerfanta`, that makes it behave as laminas' Paginator object on regards to be able to set `-1` as the max results and get all the results in that case. It requires that you install `pagerfanta/core`.
 * `DateRange`: An immutable value object wrapping two `Chronos` date objects that can be used to represent a time period between two dates.
 * `IpAddress`: An immutable value object representing an IP address that can be copied into an anonymized instance which removes the last octet.
+* `NamespacedStore`: A `symfony/lock` store that can wrap another store instance but making sure keys are prefixed with a namespace and namespace separator.

src/Lock/NamespacedStore.php

@@ -0,0 +1,77 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Shlinkio\Shlink\Common\Lock;
+
+use Closure;
+use Symfony\Component\Lock\Key;
+use Symfony\Component\Lock\SharedLockStoreInterface;
+
+use function sprintf;
+use function str_starts_with;
+
+/**
+ * Wraps a symfony/lock store and prefixes resources with a namespace.
+ */
+class NamespacedStore implements SharedLockStoreInterface
+{
+    public function __construct(
+        private readonly SharedLockStoreInterface $wrappedStore,
+        private readonly ?string $namespace = null,
+        /** Some stores may not allow default separator value. Make sure you provide the appropriate one */
+        private readonly string $namespaceSeparator = ':',
+    ) {
+    }
+
+    public function save(Key $key): void
+    {
+        $this->wrappedStore->save($this->namespaceKey($key));
+    }
+
+    public function delete(Key $key): void
+    {
+        $this->wrappedStore->delete($this->namespaceKey($key));
+    }
+
+    public function exists(Key $key): bool
+    {
+        return $this->wrappedStore->exists($this->namespaceKey($key));
+    }
+
+    public function putOffExpiration(Key $key, float $ttl): void
+    {
+        $this->wrappedStore->putOffExpiration($this->namespaceKey($key), $ttl);
+    }
+
+    public function saveRead(Key $key): void
+    {
+        $this->wrappedStore->saveRead($this->namespaceKey($key));
+    }
+
+    private function namespaceKey(Key $key): Key
+    {
+        // If no namespace was provided, just use provided key verbatim
+        if ($this->namespace === null) {
+            return $key;
+        }
+
+        // If already prefixed, just use provided key verbatim
+        $unprefixedResource = $key->__toString();
+        $prefix = $this->namespace . $this->namespaceSeparator;
+        if (str_starts_with($unprefixedResource, $prefix)) {
+            return $key;
+        }
+
+        // Sadly, the key is mutated by wrapped store, and callers take this for granted. Creating a new instance would
+        // make the reference get detached and things stop working.
+        // Instead, we need to mutate provided key object to make sure things keep working.
+        //
+        // Using Closure::bind we can run a closure using provided key as $this context, and therefore, allowing private
+        // props to be accessed
+        return Closure::bind(function (Key $mutableKey) use ($prefix, $unprefixedResource) {
+            $mutableKey->resource = sprintf('%s%s', $prefix, $unprefixedResource);
+            return $mutableKey;
+        }, null, $key)($key);
+    }
+}

test/Lock/NamespacedStoreTest.php

@@ -0,0 +1,54 @@
+<?php
+
+declare(strict_types=1);
+
+namespace ShlinkioTest\Shlink\Common\Lock;
+
+use PHPUnit\Framework\Attributes\DataProvider;
+use PHPUnit\Framework\Attributes\Test;
+use PHPUnit\Framework\MockObject\MockObject;
+use PHPUnit\Framework\TestCase;
+use Shlinkio\Shlink\Common\Lock\NamespacedStore;
+use Symfony\Component\Lock\Key;
+use Symfony\Component\Lock\SharedLockStoreInterface;
+
+class NamespacedStoreTest extends TestCase
+{
+    private MockObject & SharedLockStoreInterface $wrappedStore;
+
+    public function setUp(): void
+    {
+        $this->wrappedStore = $this->createMock(SharedLockStoreInterface::class);
+    }
+
+    #[Test, DataProvider('provideKeysAndNamespaces')]
+    public function keyIsReturnedVerbatimWhenNoNamespacesIsProvided(
+        ?string $namespace,
+        Key $key,
+        string $expectedResource,
+    ): void {
+        $store = new NamespacedStore($this->wrappedStore, $namespace);
+        $methods = [
+            'save' => [$key],
+            'delete' => [$key],
+            'exists' => [$key],
+            'putOffExpiration' => [$key, 123],
+            'saveRead' => [$key],
+        ];
+
+        foreach ($methods as $method => $args) {
+            $this->wrappedStore->expects($this->once())->method($method)->with(
+                $this->callback(fn(Key $arg) => $arg->__toString() === $expectedResource),
+            );
+
+            $store->{$method}(...$args);
+        }
+    }
+
+    public static function provideKeysAndNamespaces(): iterable
+    {
+        yield 'no namespace' => [null, new Key($expectedKey = 'base_resource'), $expectedKey];
+        yield 'namespace already set' => ['shlink', new Key('shlink:base_resource'), 'shlink:base_resource'];
+        yield 'namespace not set' => ['shlink', new Key('base_resource'), 'shlink:base_resource'];
+    }
+}