From bcc5f317b08e8723013f469ad70dfde5b3d1bd43 Mon Sep 17 00:00:00 2001
From: Shizuo Fujita <fujita@clear-code.com>
Date: Mon, 3 Aug 2026 17:46:22 +0900
Subject: [PATCH] in_tcp, in_udp, in_syslog: document deprecated parameters

Document the deprecated parameters of the socket-based input plugins.
Each is still accepted by the plugin (it only prints a deprecation
notice at runtime), but was missing from the docs.

- in_tcp: source_host_key (use source_hostname_key instead)
- in_udp: source_host_key (use source_hostname_key instead)
- in_udp: body_size_limit (use message_length_limit instead)
- in_syslog: include_source_host (use source_hostname_key or
  source_address_key instead)

Signed-off-by: Shizuo Fujita <fujita@clear-code.com>
---
 input/syslog.md | 10 ++++++++++
 input/tcp.md    | 10 ++++++++++
 input/udp.md    | 20 ++++++++++++++++++++
 3 files changed, 40 insertions(+)

diff --git a/input/syslog.md b/input/syslog.md
index 93ef1c53..716171d6 100644
--- a/input/syslog.md
+++ b/input/syslog.md
@@ -286,6 +286,16 @@ The field name of the client's hostname. If set, the client's hostname will be s
 
 The field name of the client's address. If set, the client's address will be set to its key.
 
+### `include_source_host`
+
+| type | default | version |
+| :--- | :--- | :--- |
+| bool | false | 0.10.53 |
+
+This parameter is deprecated. Use `source_hostname_key` or `source_address_key` instead.
+
+If `true`, adds the source host to the event record.
+
 ### `severity_key`
 
 | type | default | version |
diff --git a/input/tcp.md b/input/tcp.md
index c184720c..41e60ae6 100644
--- a/input/tcp.md
+++ b/input/tcp.md
@@ -133,6 +133,16 @@ You will get something like below:
 }
 ```
 
+### `source_host_key`
+
+| type | default | version |
+| :--- | :--- | :--- |
+| string | nil | 0.10.51 |
+
+This parameter is deprecated. Use `source_hostname_key` instead.
+
+The field name of the client's hostname.
+
 ### `message_length_limit`
 
 | type | default | version |
diff --git a/input/udp.md b/input/udp.md
index 10c61613..fb19b7e1 100644
--- a/input/udp.md
+++ b/input/udp.md
@@ -119,6 +119,16 @@ You will get something like this:
 }
 ```
 
+### `source_host_key`
+
+| type | default | version |
+| :--- | :--- | :--- |
+| string | nil | 0.10.51 |
+
+This parameter is deprecated. Use `source_hostname_key` instead.
+
+The field name of the client's hostname.
+
 ### `message_length_limit`
 
 | type | default | version |
@@ -127,6 +137,16 @@ You will get something like this:
 
 The maximum number of bytes for the message.
 
+### `body_size_limit`
+
+| type | default | version |
+| :--- | :--- | :--- |
+| size | nil | 0.10.51 |
+
+This parameter is deprecated. Use `message_length_limit` instead.
+
+The maximum number of bytes for the message.
+
 ### `remove_newline`
 
 | type | default | version |