From 2da67cc5bf2670122892aade13a6546263bf6e7d Mon Sep 17 00:00:00 2001
From: Tim Otten <totten@civicrm.org>
Date: Tue, 19 Jun 2018 15:09:08 -0700
Subject: [PATCH] (dev/core#174) CRM_Utils_Cache_Interface::get() should match
 PSR-16

Comparing `CRM_Utils_Cache_Interface::get()` and `Psr\SimpleCache\CacheInterface::get()`,
they agree on key details:

1. They return values are `mixed` (strings, arrays, numbers,, etc)
2. The default representation of a cache-miss is NULL.

They differ in that PSR-16 allows the caller to optionally specify a `$default`.

Since no existing callers actually use this, we can (for moment) throw an
error if someone tries to pass `$default` to a driver that doesn't support
it.

See also: https://www.php-fig.org/psr/psr-16/
---
 CRM/Utils/Cache/APCcache.php       | 6 +++++-
 CRM/Utils/Cache/ArrayCache.php     | 5 +++--
 CRM/Utils/Cache/Interface.php      | 5 +++--
 CRM/Utils/Cache/Memcache.php       | 6 +++++-
 CRM/Utils/Cache/Memcached.php      | 6 +++++-
 CRM/Utils/Cache/NoCache.php        | 5 +++--
 CRM/Utils/Cache/Redis.php          | 5 +++--
 CRM/Utils/Cache/SerializeCache.php | 7 ++++++-
 CRM/Utils/Cache/SqlGroup.php       | 6 +++++-
 9 files changed, 38 insertions(+), 13 deletions(-)

diff --git a/CRM/Utils/Cache/APCcache.php b/CRM/Utils/Cache/APCcache.php
index e696aa19c3..64c1de94b6 100644
--- a/CRM/Utils/Cache/APCcache.php
+++ b/CRM/Utils/Cache/APCcache.php
@@ -84,10 +84,14 @@ class CRM_Utils_Cache_APCcache implements CRM_Utils_Cache_Interface {
 
   /**
    * @param $key
+   * @param mixed $default
    *
    * @return mixed
    */
-  public function get($key) {
+  public function get($key, $default = NULL) {
+    if ($default !== NULL) {
+      throw new \RuntimeException("FIXME: " . __CLASS__ . "::get() only supports NULL default");
+    }
     return apc_fetch($this->_prefix . $key);
   }
 
diff --git a/CRM/Utils/Cache/ArrayCache.php b/CRM/Utils/Cache/ArrayCache.php
index b2272fa1eb..1c1b2b2979 100644
--- a/CRM/Utils/Cache/ArrayCache.php
+++ b/CRM/Utils/Cache/ArrayCache.php
@@ -63,11 +63,12 @@ class CRM_Utils_Cache_Arraycache implements CRM_Utils_Cache_Interface {
 
   /**
    * @param string $key
+   * @param mixed $default
    *
    * @return mixed
    */
-  public function get($key) {
-    return CRM_Utils_Array::value($key, $this->_cache);
+  public function get($key, $default = NULL) {
+    return CRM_Utils_Array::value($key, $this->_cache, $default);
   }
 
   /**
diff --git a/CRM/Utils/Cache/Interface.php b/CRM/Utils/Cache/Interface.php
index f11327cb59..d1d1576a3b 100644
--- a/CRM/Utils/Cache/Interface.php
+++ b/CRM/Utils/Cache/Interface.php
@@ -69,10 +69,11 @@ interface CRM_Utils_Cache_Interface {
    * Get a value from the cache.
    *
    * @param string $key
+   * @param mixed $default
    * @return mixed
-   *   NULL if $key has not been previously set
+   *   The previously set value value, or $default (NULL).
    */
-  public function get($key);
+  public function get($key, $default = NULL);
 
   /**
    * Delete a value from the cache.
diff --git a/CRM/Utils/Cache/Memcache.php b/CRM/Utils/Cache/Memcache.php
index 630589e3d8..85a1376500 100644
--- a/CRM/Utils/Cache/Memcache.php
+++ b/CRM/Utils/Cache/Memcache.php
@@ -121,10 +121,14 @@ class CRM_Utils_Cache_Memcache implements CRM_Utils_Cache_Interface {
 
   /**
    * @param $key
+   * @param mixed $default
    *
    * @return mixed
    */
-  public function &get($key) {
+  public function get($key, $default = NULL) {
+    if ($default !== NULL) {
+      throw new \RuntimeException("FIXME: " . __CLASS__ . "::get() only supports NULL default");
+    }
     $result = $this->_cache->get($this->_prefix . $key);
     return $result;
   }
diff --git a/CRM/Utils/Cache/Memcached.php b/CRM/Utils/Cache/Memcached.php
index 07315e53ce..c653154483 100644
--- a/CRM/Utils/Cache/Memcached.php
+++ b/CRM/Utils/Cache/Memcached.php
@@ -126,10 +126,14 @@ class CRM_Utils_Cache_Memcached implements CRM_Utils_Cache_Interface {
 
   /**
    * @param $key
+   * @param mixed $default
    *
    * @return mixed
    */
-  public function &get($key) {
+  public function get($key, $default = NULL) {
+    if ($default !== NULL) {
+      throw new \RuntimeException("FIXME: " . __CLASS__ . "::get() only supports NULL default");
+    }
     $key = $this->cleanKey($key);
     $result = $this->_cache->get($key);
     return $result;
diff --git a/CRM/Utils/Cache/NoCache.php b/CRM/Utils/Cache/NoCache.php
index 66c6b74cff..a7adecbe73 100644
--- a/CRM/Utils/Cache/NoCache.php
+++ b/CRM/Utils/Cache/NoCache.php
@@ -63,11 +63,12 @@ class CRM_Utils_Cache_NoCache implements CRM_Utils_Cache_Interface {
 
   /**
    * @param string $key
+   * @param mixed $default
    *
    * @return null
    */
-  public function get($key) {
-    return NULL;
+  public function get($key, $default = NULL) {
+    return $default;
   }
 
   /**
diff --git a/CRM/Utils/Cache/Redis.php b/CRM/Utils/Cache/Redis.php
index 4988b8beef..27fcb159a1 100644
--- a/CRM/Utils/Cache/Redis.php
+++ b/CRM/Utils/Cache/Redis.php
@@ -133,12 +133,13 @@ class CRM_Utils_Cache_Redis implements CRM_Utils_Cache_Interface {
 
   /**
    * @param $key
+   * @param mixed $default
    *
    * @return mixed
    */
-  public function get($key) {
+  public function get($key, $default = NULL) {
     $result = $this->_cache->get($this->_prefix . $key);
-    return ($result === FALSE) ? NULL : unserialize($result);
+    return ($result === FALSE) ? $default : unserialize($result);
   }
 
   /**
diff --git a/CRM/Utils/Cache/SerializeCache.php b/CRM/Utils/Cache/SerializeCache.php
index 6164694c3e..7ee639bd60 100644
--- a/CRM/Utils/Cache/SerializeCache.php
+++ b/CRM/Utils/Cache/SerializeCache.php
@@ -67,10 +67,15 @@ class CRM_Utils_Cache_SerializeCache implements CRM_Utils_Cache_Interface {
 
   /**
    * @param string $key
+   * @param mixed $default
    *
    * @return mixed
    */
-  public function get($key) {
+  public function get($key, $default = NULL) {
+    if ($default !== NULL) {
+      throw new \RuntimeException("FIXME: " . __CLASS__ . "::get() only supports NULL default");
+    }
+
     if (array_key_exists($key, $this->_cache)) {
       return $this->_cache[$key];
     }
diff --git a/CRM/Utils/Cache/SqlGroup.php b/CRM/Utils/Cache/SqlGroup.php
index 0bb8e98e27..402614b8f8 100644
--- a/CRM/Utils/Cache/SqlGroup.php
+++ b/CRM/Utils/Cache/SqlGroup.php
@@ -97,10 +97,14 @@ class CRM_Utils_Cache_SqlGroup implements CRM_Utils_Cache_Interface {
 
   /**
    * @param string $key
+   * @param mixed $default
    *
    * @return mixed
    */
-  public function get($key) {
+  public function get($key, $default = NULL) {
+    if ($default !== NULL) {
+      throw new \RuntimeException("FIXME: " . __CLASS__ . "::get() only supports NULL default");
+    }
     if (!array_key_exists($key, $this->frontCache)) {
       $this->frontCache[$key] = CRM_Core_BAO_Cache::getItem($this->group, $key, $this->componentID);
     }
-- 
2.25.1