Drop PSR SimpleCache

The way that interface works with multiple versions has in practice
become a nightmare of dependency management.

V1, V2 and V3 of simple cache are not compatible with each other yet
use the same name and same namespace. So that you can't have a project
using 2 libraries when one expects and requires V1 and the other expects
and requires another version.

Had those interfaces been named CacheInterface, CacheInterfaceV2 and
CacheInterfaceV3 then it would have been possible to have multiple
versions, and even type hints like `CacheInterface | CacheInterfaceV2`
would've worked.

Currently none of this is possible and it's a mess.

composer.json

@@ -20,9 +20,7 @@
         }
     ],
     "require": {
-        "php": ">=8.0",
-        "psr/simple-cache": "^2|^3",
-        "psr/cache": "^3.0"
+        "php": ">=8.0"
     },
     "suggest": {
         "ext-memcached": "Needed to use Square\\TTCache\\Store\\MemcachedStore and Square\\TTCache\\Store\\ShardedMemcachedStore implementations"

src/Store/CacheStoreException.php

@@ -1,10 +1,11 @@
-<?php declare(strict_types=1);
+<?php
+
+declare(strict_types=1);
 
 namespace Square\TTCache\Store;
 
-use Psr\SimpleCache\CacheException;
 use Exception;
 
-class CacheStoreException extends Exception implements CacheException
+class CacheStoreException extends Exception
 {
 }

src/Store/CacheStoreInterface.php

@@ -0,0 +1,20 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Square\TTCache\Store;
+
+interface CacheStoreInterface
+{
+    public function get(string $key, mixed $default = null): mixed;
+
+    public function set(string $key, mixed $value, int|\DateInterval $ttl = null): bool;
+
+    public function delete(string $key): bool;
+
+    public function getMultiple(iterable $keys, mixed $default = null): iterable;
+
+    public function setMultiple(iterable $values, int|\DateInterval $ttl = null): bool;
+
+    public function deleteMultiple(iterable $keys): bool;
+}

src/Store/MemcachedStore.php

@@ -4,17 +4,17 @@
 
 namespace Square\TTCache\Store;
 
-use Psr\SimpleCache\CacheInterface;
 use Memcached;
 
 /**
  * PSR Cache interface implementation of memcache.
  */
-class MemcachedStore implements CacheInterface
+class MemcachedStore implements CacheStoreInterface
 {
     protected Memcached $mc;
 
     private const MC_SUCCESS = 0;
+
     private const MC_NOT_FOUND = 16;
 
     private const MC_VALID_CODES = [
@@ -29,7 +29,7 @@ public function __construct(Memcached $mc)
 
     protected function checkResultCode(): void
     {
-        if (!in_array($this->mc->getResultCode(), self::MC_VALID_CODES)) {
+        if (! in_array($this->mc->getResultCode(), self::MC_VALID_CODES)) {
             throw new CacheStoreException('invalid MC return code', $this->mc->getResultCode());
         }
     }
@@ -38,10 +38,11 @@ public function get(string $key, mixed $default = null): mixed
     {
         $result = $this->mc->get($key);
         $this->checkResultCode();
+
         return $result;
     }
 
-    public function set(string $key, mixed $value, null|int|\DateInterval $ttl = null): bool
+    public function set(string $key, mixed $value, int|\DateInterval $ttl = null): bool
     {
         if (is_null($ttl)) {
             $ttl = 0;
@@ -51,13 +52,15 @@ public function set(string $key, mixed $value, null|int|\DateInterval $ttl = nul
         }
         $result = $this->mc->set($key, $value, $ttl);
         $this->checkResultCode();
+
         return $result;
     }
 
     public function delete(string $key): bool
     {
         $result = $this->mc->delete($key);
         $this->checkResultCode();
+
         return $result;
     }
 
@@ -70,20 +73,23 @@ public function getMultiple(iterable $keys, mixed $default = null): iterable
     {
         $result = $this->mc->getMulti($keys);
         $this->checkResultCode();
+
         return $result;
     }
 
-    public function setMultiple(iterable $values, null|int|\DateInterval $ttl = null): bool
+    public function setMultiple(iterable $values, int|\DateInterval $ttl = null): bool
     {
         $result = $this->mc->setMulti($values, $ttl ?? 0);
         $this->checkResultCode();
+
         return $result;
     }
 
     public function deleteMultiple(iterable $keys): bool
     {
         $result = $this->mc->deleteMulti($keys);
         $this->checkResultCode();
+
         return true;
     }
 

src/Store/ShardedMemcachedStore.php

@@ -1,21 +1,23 @@
-<?php declare(strict_types=1);
+<?php
+
+declare(strict_types=1);
 
 namespace Square\TTCache\Store;
 
-use Psr\SimpleCache\CacheInterface;
 use Memcached;
 
 /**
  * PSR Cache interface implementation of memcache that needs to receive a sharding key
  * and ensures all the values stored through this instance end up on the same MC server.
  */
-class ShardedMemcachedStore implements CacheInterface
+class ShardedMemcachedStore implements CacheStoreInterface
 {
     protected Memcached $mc;
 
     protected string $shardingKey;
 
     private const MC_SUCCESS = 0;
+
     private const MC_NOT_FOUND = 16;
 
     private const MC_VALID_CODES = [
@@ -28,14 +30,14 @@ public function __construct(Memcached $mc)
         $this->mc = $mc;
     }
 
-    public function setShardingKey(string $key) : void
+    public function setShardingKey(string $key): void
     {
         $this->shardingKey = $key;
     }
 
-    protected function checkResultCode() : void
+    protected function checkResultCode(): void
     {
-        if (!in_array($this->mc->getResultCode(), self::MC_VALID_CODES)) {
+        if (! in_array($this->mc->getResultCode(), self::MC_VALID_CODES)) {
             throw new CacheStoreException('invalid MC return code', $this->mc->getResultCode());
         }
     }
@@ -44,20 +46,23 @@ public function get(string $key, mixed $default = null): mixed
     {
         $result = $this->mc->getByKey($this->shardingKey, $key);
         $this->checkResultCode();
+
         return $result;
     }
 
-    public function set(string $key, mixed $value, null|int|\DateInterval $ttl = null): bool
+    public function set(string $key, mixed $value, int|\DateInterval $ttl = null): bool
     {
         $result = $this->mc->setByKey($this->shardingKey, $key, $value, $ttl ?? 0);
         $this->checkResultCode();
+
         return $result;
     }
 
     public function delete(string $key): bool
     {
         $result = $this->mc->deleteByKey($this->shardingKey, $key);
         $this->checkResultCode();
+
         return $result;
     }
 
@@ -70,20 +75,23 @@ public function getMultiple(iterable $keys, mixed $default = null): iterable
     {
         $result = $this->mc->getMultiByKey($this->shardingKey, $keys);
         $this->checkResultCode();
+
         return $result;
     }
 
-    public function setMultiple(iterable $values, null|int|\DateInterval $ttl = null): bool
+    public function setMultiple(iterable $values, int|\DateInterval $ttl = null): bool
     {
         $result = $this->mc->setMultiByKey($this->shardingKey, $values, $ttl ?? 0);
         $this->checkResultCode();
+
         return $result;
     }
 
     public function deleteMultiple(iterable $keys): bool
     {
         $result = $this->mc->deleteMultiByKey($this->shardingKey, $keys);
         $this->checkResultCode();
+
         return $result;
     }