From a32220442c8c4d36f343e7b08ba9a30ff8cfe951 Mon Sep 17 00:00:00 2001
From: Sascha Nitsch <sascha.nitsch@spsn.net>
Date: Wed, 17 Jul 2024 21:45:33 +0200
Subject: [PATCH] basic redis cache support

---
 README.md              |  6 ++++
 php/data/user.php      | 35 ++++++++++++++++++++-
 php/dio/user.php       | 20 +++++++-----
 plugins/rediscache.php | 70 ++++++++++++++++++++++++++++++++++++++++--
 progress.md            |  3 +-
 rediscache.ini         |  5 +++
 6 files changed, 127 insertions(+), 12 deletions(-)
 create mode 100644 rediscache.ini

diff --git a/README.md b/README.md
index 61c7ed5..5bf2d67 100644
--- a/README.md
+++ b/README.md
@@ -25,6 +25,12 @@ Needed SQL commands:
 
 This will be changed, but works for the current develop verison.
 
+If the include redis cache is enabled, create a users.acl for redis with the content:
+
+    user federator on ~u_* +get +set >redis*change*password
+
+change password in the rediscache.ini to match your given password.
+
 To configure an apache server, add the following rewrite rules:
 
     <Directory /where/ever/you/put/it>
diff --git a/php/data/user.php b/php/data/user.php
index ac94a60..78f8be1 100644
--- a/php/data/user.php
+++ b/php/data/user.php
@@ -38,6 +38,25 @@ class User
      * */
     public $session;
 
+    /**
+     * create new user object from json string
+     *
+     * @param string $input input string
+     * @return User|false
+     */
+    public static function createFromJson($input)
+    {
+        $data = json_decode($input, true);
+        if ($data === null) {
+            return false;
+        }
+        $user = new User();
+        $user->id = $data['id'];
+        /// TODO: replace with enums
+        $user->permissions = $data['permissions'];
+        return $user;
+    }
+
     /**
      * check if use has asked permission
      * @param string $p @unused-param
@@ -48,6 +67,20 @@ class User
      */
     public function hasPermission(string $p)
     {
-        return in_array($p, $this->permissions);
+        return in_array($p, $this->permissions, false);
+    }
+
+    /**
+     * convert internal data to json string
+     *
+     * @return string
+     */
+    public function toJson()
+    {
+        $data = [
+          'id' => $this->id,
+          'permissions' => $this->permissions
+        ];
+        return json_encode($data) | '';
     }
 }
diff --git a/php/dio/user.php b/php/dio/user.php
index c1e5d86..e75d2c9 100644
--- a/php/dio/user.php
+++ b/php/dio/user.php
@@ -33,28 +33,32 @@ class User
      *          session
      * @param string $_user
      *          user/profile name
-     * @param \Connector\Connector? $connector @unused-param
+     * @param \Federator\Connector\Connector $connector
      *          connector to fetch use with
-     * @param \Cache\Cache? $cache
+     * @param \Federator\Cache\Cache|null $cache
      *          optional caching service
-     * @return \Data\User|bool
+     * @return \Federator\Data\User|false
      */
     public static function getUserBySession($dbh, $_session, $_user, $connector, $cache)
     {
+        $saveToCache = false;
         $user = false;
-        if ($cache) {
+        if ($cache !== null) {
             $user = $cache->getRemoteUserBySession($_session, $_user);
         }
 
-        // ask connector for user-id
-        $user = $connector->getRemoteUserBySession($_session, $_user);
+        if ($user === false) {
+            // ask connector for user-id
+            $user = $connector->getRemoteUserBySession($_session, $_user);
+            $saveToCache = true;
+        }
         if ($user === false) {
             return false;
         }
-        if ($cache) {
+        self::extendUser($dbh, $user);
+        if ($cache !== null && $saveToCache) {
             $cache->saveRemoteUserBySession($_session, $_user, $user);
         }
-        self::extendUser($dbh, $user);
         return $user;
     }
 }
diff --git a/plugins/rediscache.php b/plugins/rediscache.php
index 63cb805..8bbef5f 100644
--- a/plugins/rediscache.php
+++ b/plugins/rediscache.php
@@ -13,6 +13,20 @@ namespace Federator\Cache;
  */
 class RedisCache implements Cache
 {
+    /**
+     * config data
+     *
+     * @var array<string, mixed> $config
+     */
+    private $config;
+
+    /**
+     * connection to redis open flag
+     *
+     * @var bool $connected
+     */
+    private $connected = false;
+
     /**
      * connection handle
      *
@@ -25,20 +39,72 @@ class RedisCache implements Cache
      */
     public function __construct()
     {
+        $config = parse_ini_file('../rediscache.ini');
+        if ($config !== false) {
+            $this->config = $config;
+        }
     }
 
     /**
-     * {@inheritDoc}
+     * connect to redis
+     * @return void
+     */
+    private function connect()
+    {
+         $this->redis = new \Redis();
+         $this->redis->pconnect($this->config['host'], intval($this->config['port'], 10));
+         // @phan-suppress-next-line PhanTypeMismatchArgumentInternalProbablyReal
+         $this->redis->auth([$this->config['username'], $this->config['password']]);
+    }
+
+    /**
+     * create key from session and user
+     *
+     * @param string $prefix prefix to create name spaces
+     * @param string $_session session id
+     * @param string $_user user/profile name
+     * @return string key
+     */
+    private static function createKey($prefix, $_session, $_user)
+    {
+        $key = $prefix . '_';
+        $key .= md5($_session . $_user);
+        return $key;
+    }
+    /**
+     * get remote user by given session
+     *
+     * @param string $_session session id
+     * @param string $_user user/profile name
+     * @return \Federator\Data\User | false
      */
     public function getRemoteUserBySession($_session, $_user)
     {
+        if (!$this->connected) {
+            $this->connect();
+        }
+        $key = self::createKey('u', $_session, $_user);
+        $data = $this->redis->get($key);
+        if ($data === false) {
+            return false;
+        }
+        $user = \Federator\Data\User::createFromJson($data);
+        return $user;
     }
 
     /**
-     * {@inheritDoc}
+     * save remote user by given session
+     *
+     * @param string $_session session id
+     * @param string $_user user/profile name
+     * @param \Federator\Data\User $user user data
+     * @return void
      */
     public function saveRemoteUserBySession($_session, $_user, $user)
     {
+        $key = self::createKey('u', $_session, $_user);
+        $serialized = $user->toJson();
+        $this->redis->set($key, $serialized);
     }
 }
 
diff --git a/progress.md b/progress.md
index 851b42c..1f0494d 100644
--- a/progress.md
+++ b/progress.md
@@ -14,8 +14,9 @@ primary goal is to connect ContentNation via ActivityPub again.
 ## roadmap to v1.0
 - [X] API framework
 - [X] interfact to connect to existing service
+- [X] cache layer for users minmal version
 - [ ] overlay to extend with needed info like private keys, urls, ...
-- [ ] cache layer for users
+- [ ] full cache for users
 - [ ] webfinger
 - [ ] discovery endpoints
 - [ ] ap outbox
diff --git a/rediscache.ini b/rediscache.ini
new file mode 100644
index 0000000..52244cd
--- /dev/null
+++ b/rediscache.ini
@@ -0,0 +1,5 @@
+[redis]
+host = localhost
+port = 6379
+username = federator
+password = redis*change*password