Add Block Index APi

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

_api-reference/index-apis/blocks.md

@@ -0,0 +1,58 @@
+---
+layout: default
+title: Blocks
+parent: Index APIs
+nav_order: 6
+---
+
+# Blocks
+**Introduced 1.0**
+{: .label .label-purple }
+
+The Blocks API limits which operations are available on the specified index. OpenSearch provides different types of blocks that allow you to restrict write, read, or metadata operations on an index.  When adding a write block through the API, it ensures that all shards of the index have properly accounted for the block before returning a successful response to the user. This means that any in-flight write operations to the index have been completed before the write block takes effect.
+
+## Path and HTTP methods
+
+```json
+PUT /<index>/_block/<block>
+```
+
+## Path parameters
+
+| Parameter | Type | Description |
+:--- | :--- | :---
+| `index` | String | A comma-delimited list of index names. Wildcard expressions (`*`) are supported. To target all data streams and indexes in a cluster, use `_all` or `*`. Optional. |
+| `<block>` | String | Specifies the type of block to apply to the index.  Valid values are: <br> `metadata`: Disables all metadata changes, such as closing the index. <br> `read`: Disables any read operations. <br> `read_only`: Disables any write operations and metadata changes. <br> `write`: Disables write operations. However, metadata changes are still allowed. |
+
+## Query parameters
+
+The following table lists the available query parameters. All query parameters are optional.
+
+| Parameter | Data type | Description |
+| :--- | :--- | :--- |
+| `ignore_unavailable` | Boolean | When `false`, the request returns an error when it targets a missing or closed index. Default is `false`.
+| `allow_no_indices` | Boolean | When `false`, the Refresh Index API returns an error when a wildcard expression, index alias, or `_all` targets only closed or missing indexes, even when the request is made against open indexes. Default is `true`. |
+| `expand_wildcards` | String | The type of index that the wildcard patterns can match. If the request targets data streams, this argument determines whether the wildcard expressions match any hidden data streams. Supports comma-separated values, such as `open,hidden`. Valid values are `all`, `open`, `closed`, `hidden`, and `none`. |
+`cluster_manager_timeout` | Time | The amount of time to wait for a connection to the cluster manager node. Default is `30s`.
+`timeout` | Time | The amount of time to wait for the request to return. Default is `30s`. |
+
+## Example request
+
+The following example request disables any `write` operations made to the test index:
+
+```json
+PUT /test-index/_block/write
+```
+
+## Example response
+
+```json
+{
+  "acknowledged" : true,
+  "shards_acknowledged" : true,
+  "indices" : [ {
+    "name" : "test-index",
+    "blocked" : true
+  } ]
+}
+```