Add new rename_alias parameters for restore-snapshot (#8544)

* Add new rename_alias parameters for restore-snapshot

Signed-off-by: Spencer G. Jones <[email protected]>

* Updating per review

Signed-off-by: Spencer G. Jones <[email protected]>

* Apply suggestions from code review

Signed-off-by: Naarcha-AWS <[email protected]>

* Apply suggestions from code review

Co-authored-by: Nathan Bower <[email protected]>
Signed-off-by: Naarcha-AWS <[email protected]>

---------

Signed-off-by: Spencer G. Jones <[email protected]>
Signed-off-by: Naarcha-AWS <[email protected]>
Co-authored-by: Naarcha-AWS <[email protected]>
Co-authored-by: Nathan Bower <[email protected]>

_api-reference/snapshots/restore-snapshot.md

@@ -51,8 +51,10 @@ All request body parameters are optional.
 | index_settings | String | A comma-delimited list of settings to add or change in all restored indices. Use this parameter to override index settings during snapshot restoration. For data streams, these index settings are applied to the restored backing indices. |
 | indices | String | A comma-delimited list of data streams and indices to restore from the snapshot. Multi-index syntax is supported. By default, a restore operation includes all data streams and indices in the snapshot. If this argument is provided, the restore operation only includes the data streams and indices that you specify. |
 | partial | Boolean | How the restore operation will behave if indices in the snapshot do not have all primary shards available. If `false`, the entire restore operation fails if any indices in the snapshot do not have all primary shards available. <br /> <br />If `true`, allows the restoration of a partial snapshot of indices with unavailable shards. Only shards that were successfully included in the snapshot are restored. All missing shards are recreated as empty. By default, the entire restore operation fails if one or more indices included in the snapshot do not have all primary shards available. To change this behavior, set `partial` to `true`. Defaults to `false`. |
-| rename_pattern | String | The pattern to apply to restored data streams and indices. Data streams and indices matching the rename pattern will be renamed according to `rename_replacement`. <br /><br />The rename pattern is applied as defined by the regular expression that supports referencing the original text. <br /> <br />The request fails if two or more data streams or indices are renamed into the same name. If you rename a restored data stream, its backing indices are also renamed. For example, if you rename the logs data stream to `recovered-logs`, the backing index `.ds-logs-1` is renamed to `.ds-recovered-logs-1`. <br /> <br />If you rename a restored stream, ensure an index template matches the new stream name. If there are no matching index template names, the stream cannot roll over and new backing indices are not created.|
-| rename_replacement | String | The rename replacement string. See `rename_pattern` for more information.|
+| rename_pattern | String | The pattern to apply to the restored data streams and indexes. Data streams and indexes matching the rename pattern will be renamed according to the `rename_replacement` setting. <br /><br /> The rename pattern is applied as defined by the regular expression that supports referencing the original text. <br /> <br /> The request fails if two or more data streams or indexes are renamed to the same name. If you rename a restored data stream, its backing indexes are also renamed. For example, if you rename the logs data stream to `recovered-logs`, the backing index `.ds-logs-1` is renamed to `.ds-recovered-logs-1`. <br /> <br /> If you rename a restored stream, ensure an index template matches the new stream name. If there are no matching index template names, the stream cannot roll over, and new backing indexes are not created.|
+| rename_replacement | String | The rename replacement string.|
+| rename_alias_pattern | String | The pattern to apply to the restored aliases. Aliases matching the rename pattern will be renamed according to the `rename_alias_replacement` setting. <br /><br /> The rename pattern is applied as defined by the regular expression that supports referencing the original text. <br /> <br /> If two or more aliases are renamed to the same name, these aliases will be merged into one.|
+| rename_alias_replacement | String | The rename replacement string for aliases.|
 | source_remote_store_repository | String | The name of the remote store repository of the source index being restored. If not provided, the Snapshot Restore API will use the repository that was registered when the snapshot was created.
 | wait_for_completion | Boolean | Whether to return a response after the restore operation has completed.  If `false`, the request returns a response when the restore operation initializes.  If `true`, the request returns a response when the restore operation completes. Defaults to `false`. |
 
@@ -123,4 +125,4 @@ If open indices in a snapshot already exist in a cluster, and you don't delete,
   },
   "status" : 500
 }
-````
+````

_tuning-your-cluster/availability-and-recovery/snapshots/snapshot-restore.md

@@ -479,15 +479,19 @@ Request parameters | Description
 `include_global_state` | Whether to restore the cluster state. Default is `false`.
 `include_aliases` | Whether to restore aliases alongside their associated indexes. Default is `true`.
 `partial` | Whether to allow the restoration of partial snapshots. Default is `false`.
-`rename_pattern` | If you want to rename indexes as you restore them, use this option to specify a regular expression that matches all indexes you want to restore. Use capture groups (`()`) to reuse portions of the index name.
-`rename_replacement` | If you want to rename indexes as you restore them, use this option to specify the replacement pattern. Use `$0` to include the entire matching index name, `$1` to include the content of the first capture group, and so on.
+`rename_pattern` | If you want to rename indexes, use this option to specify a regular expression that matches all the indexes that you want to restore and rename. Use capture groups (`()`) to reuse portions of the index name.
+`rename_replacement` | If you want to rename indexes, use this option to specify the name replacement pattern. Use `$0` to include the entire matching index name or the number of the capture group. For example, `$1` would include the content of the first capture group.
+`rename_alias_pattern` | If you want to rename aliases, use this option to specify a regular expression that matches all the aliases you want to restore and rename. Use capture groups (`()`) to reuse portions of the alias name.
+`rename_alias_replacement` | If you want to rename aliases, use this option to specify the name replacement pattern. Use `$0` to include the entire matching alias name or the number of the capture group. For example, `$1` would include the content of the first capture group.
 `index_settings` | If you want to change [index settings]({{site.url}}{{site.baseurl}}/im-plugin/index-settings/) applied during the restore operation, specify them here. You cannot change `index.number_of_shards`.
 `ignore_index_settings` | Rather than explicitly specifying new settings with `index_settings`, you can ignore certain index settings in the snapshot and use the cluster defaults applied during restore. You cannot ignore `index.number_of_shards`, `index.number_of_replicas`, or `index.auto_expand_replicas`.
 `storage_type` | `local` indicates that all snapshot metadata and index data will be downloaded to local storage. <br /><br > `remote_snapshot` indicates that snapshot metadata will be downloaded to the cluster, but the remote repository will remain the authoritative store of the index data. Data will be downloaded and cached as necessary to service queries. At least one node in the cluster must be configured with the [search role]({{site.url}}{{site.baseurl}}/security/access-control/users-roles/) in order to restore a snapshot using the type `remote_snapshot`. <br /><br > Defaults to `local`.
 
 ### Conflicts and compatibility
 
-One way to avoid naming conflicts when restoring indexes is to use the `rename_pattern` and `rename_replacement` options. You can then, if necessary, use the `_reindex` API to combine the two. The simpler way is to delete existing indexes prior to restoring from a snapshot.
+One way to avoid index naming conflicts when restoring indexes is to use the `rename_pattern` and `rename_replacement` options. You can then, if necessary, use the `_reindex` API to combine the two. However, it may be simpler to delete the indexes that caused the conflict prior to restoring them from a snapshot.
+
+Similarly, to avoid alias naming conflicts when restoring indexes with aliases, you can use the `rename_alias_pattern` and `rename_alias_replacement` options. 
 
 You can use the `_close` API to close existing indexes prior to restoring from a snapshot, but the index in the snapshot has to have the same number of shards as the existing index.