chore: 3.8 breaking changes (#7818)

* Add 3.8 breaking changes

Signed-off-by: Diana <[email protected]>

* Add custom plugin migration steps for Redis changes

Signed-off-by: Diana <[email protected]>

* Apply code review feedback

Signed-off-by: Diana <[email protected]>

---------

Signed-off-by: Diana <[email protected]>

app/_src/gateway/breaking-changes/38x.md

@@ -15,4 +15,49 @@ Review the [changelog](/gateway/changelog/#3800) for all the changes in this rel
 
 ## Breaking changes and deprecations
 
-TBA
+### `kong.logrotate` configuration file no longer overwritten during upgrade
+The `kong.logrotate` configuration file will no longer be overwritten during upgrade.
+When upgrading, set the environment variable `DEBIAN_FRONTEND=noninteractive` on Debian/Ubuntu to avoid any interactive prompts and enable fully automatic upgrades.
+
+### `log_statistics` defaults to `false` for AI Proxy
+A configuration validation was added to the [AI Proxy plugin](/hub/kong-inc/ai-proxy/) to prevent users from enabling `log_statistics` for
+providers that don't support statistics. In addition, the default of `log_statistics` was changed from
+`true` to `false`, and a database migration is added as well for disabling `log_statistics` if it
+has already been enabled upon unsupported providers.
+
+### Custom plugins that used shared Redis config
+
+In 3.8.0.0, Kong has changed and refactored the shared Redis configuration that previously was imported by `require "kong.enterprise_edition.redis"`. If you created a custom plugin that is using this shared configuration or if you have a forked version of a plugin, like `rate-limiting-advanced`, then you might need to do additional steps before you can upgrade to the new version of this Redis config.
+
+Out of the box, custom plugins should still work since the old shared configuration is still available. The new config adds the `cluster_max_redirections` option for Redis Cluster, and the `cluster_nodes` format and `sentinel_nodes` were changed. Other than that, the initialization step is no longer required.
+
+#### Upgrade custom plugins using a shared Redis config
+
+If your plugin is using a shared Redis config (for example, if you import `require "kong.enterprise_edition.redis"`) you must do the following:
+
+1. Remove the `redis.init_conf(conf)` library initialization call.
+    Where `redis` is `local redis = require "kong.enterprise_edition.redis"`.
+1. Switch the imports of redis from `local redis = require "kong.enterprise_edition.redis"` to `local redis = require "kong.enterprise_edition.tools.redis.v2"`.
+
+#### Upgrade custom plugins using the rate limiting library
+
+If your plugin is using rate limiting library (as in you import `local ratelimiting = require("kong.tools.public.rate-limiting").new_instance("your-plugin-name")`) you must switch the imports of the following:
+
+* **Shared Redis config:** Change `local redis = require "kong.enterprise_edition.redis"` to `local redis = require "kong.enterprise_edition.tools.redis.v2"`
+* **Rate limiting library:** Change `local ratelimiting = require("kong.tools.public.rate-limiting").new_instance("your-plugin-name")` to `local ratelimiting = require("kong.tools.public.rate-limiting").new_instance("your-plugin-name", { redis_config_version = "v2" })`
+
+### Deprecations
+
+#### `sentinel_addresses` and `cluster_addresses` for Redis
+
+The following plugins switched `cluster_addresses` to `cluster_nodes` and `sentinel_addresses` to `sentinel_nodes` for Redis configuration:
+
+* [AI Rate Limiting Advanced](/hub/kong-inc/ai-rate-limiting-advanced/)
+* [GraphQL Proxy Caching Advanced](/hub/kong-inc/graphql-proxy-cache-advanced/)
+* [GraphQL Rate Limiting Advanced](/hub/kong-inc/graphql-rate-limiting-advanced/)
+* [Proxy Caching Advanced](/hub/kong-inc/proxy-cache-advanced/)
+* [Rate Limiting Advanced](/hub/kong-inc/rate-limiting-advanced/)
+
+These fields are converted automatically when you run `kong migrations up`. Also, any changes uploaded via decK or the Admin API using the old `cluster_addresses` and `sentinel_addresses` are respected and properly translated to the new fields.
+
+Forked custom plugins aren't automatically migrated. For more information about how to migrate custom plugins, see [Custom plugins that used shared Redis config](#custom-plugins-that-used-shared-redis-config).