WP Redis

对于需要处理高流量、提高登录用户访问速度或动态页面负载的网站来说，高速持久的对象缓存是必不可少的。此外，您还需要能在应用程序的多个实例中进行扩展的缓存，因此不能使用本地文件缓存或 APC。 Redis is a great answer, and one we bundle on the Pantheon platform. This is our plugin for integrating with the cache, but you can use it on any self-hosted WordPress site if you have Redis. Install from WordPress.org or Github. 值得注意的是，持久化对象缓存并非万能--页面加载时调用 2,000 次 Redis，就相当于进行了整整 2 秒钟的对象缓存事务处理。请确保明智地使用对象缓存：保持合理的键数，不要在每个键上存储大量数据，并避免前端急速写入和删除。 Go forth and make awesome! And, once you've built something great, send us feature requests (or bug reports). Take a look at the wiki for useful code snippets and other tips.

This assumes you have a PHP environment with the required PhpRedis extension and a working Redis server (e.g. Pantheon). WP Redis also works with Predis via humanmade/wp-redis-predis-client.

1. Install object-cache.php to wp-content/object-cache.php with a symlink or by copying the file.
2. 如果不是在 Pantheon 上运行，请编辑 wp-config.php，添加缓存证书，例如

$redis_server = array( 'host' => '127.0.0.1', 'port' => 6379, 'auth' => '12345', 'database' => 0, // Optionally use a specific numeric Redis database. Default is 0. ); 3. If your Redis server is listening through a sockt file instead, set its path on host parameter and change the port to null: $redis_server = array( 'host' => '/path/of/redis/socket-file.sock', 'port' => null, 'auth' => '12345', 'database' => 0, // Optionally use a specific numeric Redis database. Default is 0. ); 4. 启动推进器：现在您正在使用 Redis 支持 WP 的对象缓存。 5. (Optional) To use the wp redis WP-CLI commands, activate the WP Redis plugin. No activation is necessary if you're solely using the object cache drop-in. 6. (Optional) To use the same Redis server with multiple, discreet WordPress installs, you can use the WP_CACHE_KEY_SALT constant to define a unique salt for each install. 7. (Optional) To use true cache groups, with the ability to delete all keys for a given group, register groups with wp_cache_add_redis_hash_groups(), or define the WP_REDIS_USE_CACHE_GROUPS constant to true to enable with all groups. However, when enabled, the expiration value is not respected because expiration on group keys isn't a feature supported by Redis. 8. (Optional) On an existing site previously using WordPress' transient cache, use WP-CLI to delete all (%_transient_%) transients from the options table: wp transient delete-all. WP Redis assumes responsibility for the transient cache. 9. (Optional) To use Relay instead of PhpRedis as the client define the WP_REDIS_USE_RELAY constant to true. For support requests, please use Relay's GitHub discussions.

1.4.4 (November 27, 2023)

• Updates Pantheon WP Coding Standards to 2.0 [#445]
• Handle duplicate keys in get_multiple function [#448] (props @souptik)

1.4.3 (June 26, 2023)

• Bug fix: Fixes assumption that CACHE_PORT & CACHE_PASSWORD are Set. [428] (props @tnolte)
• Adds WP.org validation GitHub action [#435]
• Bug fix: Fixes incorrect order of array_replace_recursive and other issues [434] (props @timnolte)
• Bug fix: Replace use of wp_strip_all_tags in object-cache.php [434] (props @timnolte)
• Bug fix: Don't strip tags from the cache password. [434] (props @timnolte)

1.4.2 (May 15, 2023)

• Bug fix: Removes exception loop caused by esc_html in _exception_handler() [421]

1.4.1 (May 11, 2023)

• Bug fix: wp_cache_flush_runtime should only clear the local cache [413]

1.4.0 (May 9, 2023)

• Add support for flush_runtime and flush_group functions [#405]
• Add pantheon-wp-coding-standards [#400]
• Update CONTRIBUTING.MD [#406]
• Update Composer dependencies [#401]

1.3.5 (April 6, 2023)

• 将测试版本提升至 6.2
• Update Composer dependencies [#394]

1.3.4 (March 7, 2023)

• Set missing_redis_message if Redis service is not connected [#391].

1.3.3 (February 28, 2023)

• Add PHP 8.2 support [#388].
• Remove Grunt, add valid license to Composer file [#387].
• Update Composer dependencies [#384] [#385].

1.3.2 (December 5, 2022)

• Fix broken wp_cache_supports function [#382].

1.3.1 (December 2, 2022)

• Declare wp_cache_supports function and support features. [#378]
• Make dependabot target develop branch for PRs. [#376]

1.3.0 (November 29, 2022)

• Added CONTRIBUTING.MD and GitHub action to automate deployments to wp.org. [#368]

1.2.0 (February 17, 2022)

• Adds support for Relay via WP_REDIS_USE_RELAY constant [#344].

1.1.4 (October 21, 2021)

• Fixes some faulty logic in WP_REDIS_IGNORE_GLOBAL_GROUPS check [#333].

1.1.3 (October 21, 2021)

• Supports a WP_REDIS_IGNORE_GLOBAL_GROUPS constant to prevent groups from being added to global caching group [#331].

1.1.2 (March 24, 2021)

• Applies logic used elsewhere to fall back to $_SERVER in wp_redis_get_info() [#316].

1.1.1 (August 17, 2020)

• Returns cache data in correct order when using wp_cache_get_multiple() and internal cache is already primed [#292].

1.1.0 (July 13, 2020)

• Implements wp_cache_get_multiple() for WordPress 5.5 [#287].
• Bails early when connecting to Redis throws an Exception to avoid fatal error [285].

1.0.1 (April 14, 2020)

• Adds support for specifying Redis database number from environment/server variables [#273].

1.0.0 (March 2, 2020)

• 插件稳定。

0.8.3 (February 24, 2020)

• Fixes wp redis cli by using proc_open() directly, instead of WP_CLI::launch() [#268].

0.8.2 (January 15, 2020)

• Catches exceptions when trying to connect to Redis [#265].

0.8.1 (January 10, 2020)

• Adds WP_REDIS_DEFAULT_EXPIRE_SECONDS constant to set default cache expire value [#264].

0.8.0 (January 6, 2020)

• Uses flushdb instead of flushAll to avoid flushing the entire Redis instance [#259].

0.7.1 (December 14, 2018)

• Better support in wp_cache_init() for drop-ins like LudicrousDB [#231].
• 清除 PHPCS 问题。

0.7.0 (August 22, 2017)

• Adds filterable connection methods to permit use of Predis. See humanmade/wp-redis-predis-client for more details.

0.6.2 (June 5, 2017)

• 错误修复：在内部缓存中保留空值。
• 错误修正：获取数值时将其转换为真实类型。

0.6.1 (February 23, 2017)

• Bug fix: correctly passes an empty password to redis-cli.
• 对测试套件进行各种改进。

0.6.0 (September 21, 2016)

• Introduces three new WP-CLI commands: wp redis debug to display cache hit/miss ratio for any URL; wp redis info to display high-level Redis statistics; wp redis enable to create the object-cache.php symlink.
• Permits a Redis database to be defined with $redis_server['database'].
• Introduces wp_cache_add_redis_hash_groups(), which permits registering specific groups to use Redis hashes, and is more precise than our existing WP_REDIS_USE_CACHE_GROUPS constant.

0.5.0 (April 27, 2016)

• Performance boost! Removes redundant exists call from wp_cache_get(), which easily halves the number of Redis calls.
• Uses add_action() and $wpdb in a safer manner for compatibility with Batcache, which loads the object cache before aforementioned APIs are available.
• 为调试目的，跟踪调用 Redis 的次数，包括调用类型的细分。
• 针对现有功能添加了一系列更明确的测试覆盖范围。
• For consistency with the actual Redis call, calls del instead of delete.
• Bug fix: If a group isn't persistent, don't ever make an exists call against Redis.

0.4.0 (March 23, 2016)

• Introduces wp redis-cli, a WP-CLI command to launch redis-cli with WordPress' Redis credentials.
• 错误修正：通过写入 sitemeta 表而不是活动网站的选项表，确保故障回退机制在多网站上按预期运行。
• Bug fix: Uses 'default' as the default cache group, mirroring WordPress core, such that $wp_object_cache->add( 'foo', 'bar' ) === wp_cache_add( 'foo', 'bar' ).

0.3.0 (February 11, 2016)

• Introduces opt-in support for Redis cache groups. Enable with define( 'WP_REDIS_USE_CACHE_GROUPS', true );. When enabled, WP Redis persists cache groups in a structured manner, instead of hashing the cache key and group together.
• Uses PHP_CodeSniffer and WordPress Coding Standards sniffs to ensure WP Redis adheres to WordPress coding standards.
• Bug fix: Permits use of a Unix socket in $redis_server['host'] by ensuring the supplied $port is null.

0.2.2 (November 24, 2015)

• Bug fix: use INSERT IGNORE INTO instead of INSERT INTO to prevent SQL errors when two concurrent processes attempt to write failback flag at the same time.
• Bug fix: use E_USER_WARNING with trigger_error().
• 错误修正：捕捉身份验证过程中抛出的异常，允许失败后返回内部对象缓存。

0.2.1 (November 17, 2015)

• Bug fix: prevent SQL error when $wpdb->options isn't yet initialized on multisite.

0.2.0 (November 17, 2015)

• 当 Redis 不可用或时断时续时，WordPress 会优雅地退回到对象缓存。在此之前，WP Redis 会出现致命故障。
• 如果 Redis 在请求中途消失，会触发 PHP 错误，以便在日志中进行监控。根据特定错误信息尝试重新连接。
• Forces a flushAll on Redis when Redis comes back after failing. This behavior can be disabled with the WP_REDIS_DISABLE_FAILBACK_FLUSH constant.
• 当 Redis 不可用但预计会可用时，显示管理员通知。

0.1

• 首次提交工作代码，让所有人受益。