From 2e5d8f66a48afb3d33a2d59bd52f74b0aba1ab73 Mon Sep 17 00:00:00 2001
From: Rob Bavey <rob.bavey@elastic.co>
Date: Mon, 15 Sep 2025 11:25:08 -0400
Subject: [PATCH 1/2] Update data streams documentation to note that sprintf
 syntax is not supported

Using sprintf syntax in the `data_streams` options is not supported. This commit
adds a supplemental note, explaining this, and providing an example on how to
dynamically route using `mutate` filter and the auto routing facility.

Relates: https://github.com/elastic/logstash/issues/17689
---
 docs/index.asciidoc | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/docs/index.asciidoc b/docs/index.asciidoc
index 3611c04b..744492a5 100644
--- a/docs/index.asciidoc
+++ b/docs/index.asciidoc
@@ -136,6 +136,22 @@ output {
 }
 -----
 
+NOTE: Dynamic variable substitution using sprintf syntax, such as %{foo}, is not supported in the `data_stream` options
+      at this time. If you want to dynamically route to data streams, you can add the appropriate fields to events in
+      the configuration and take advantage of the (on by default) auto routing facility:
+
+[source,sh]
+-----
+filter {
+      mutate {
+              add_field => {
+                      "[data_stream][type]" => "logs"
+                      "[data_stream][dataset]" => "%{dataset_name}"
+                      "[data_stream][namespace]" => "%{namespace_name}"
+              }
+      }
+}
+-----
 
 ==== Writing to different indices: best practices
 

From 6e76b3977e1d3a5b0eee7d004d768ac2ef06120d Mon Sep 17 00:00:00 2001
From: Rob Bavey <rob.bavey@elastic.co>
Date: Fri, 24 Oct 2025 16:02:40 -0400
Subject: [PATCH 2/2] Add changelog, update version

---
 CHANGELOG.md                          | 3 +++
 logstash-output-elasticsearch.gemspec | 2 +-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 14d59640..52845415 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,6 @@
+## 12.1.1
+ - Update documentation to state that that sprintf syntax is not supported for datastreams, and give a workaround [#1224](https://github.com/logstash-plugins/logstash-output-elasticsearch/pull/1224)
+
 ## 12.1.0
  - Add drop_error_types config option to not retry after certain error types [#1228](https://github.com/logstash-plugins/logstash-output-elasticsearch/pull/1228)
 
diff --git a/logstash-output-elasticsearch.gemspec b/logstash-output-elasticsearch.gemspec
index f884bdeb..31e82ac1 100644
--- a/logstash-output-elasticsearch.gemspec
+++ b/logstash-output-elasticsearch.gemspec
@@ -1,6 +1,6 @@
 Gem::Specification.new do |s|
   s.name            = 'logstash-output-elasticsearch'
-  s.version         = '12.1.0'
+  s.version         = '12.1.1'
   s.licenses        = ['apache-2.0']
   s.summary         = "Stores logs in Elasticsearch"
   s.description     = "This gem is a Logstash plugin required to be installed on top of the Logstash core pipeline using $LS_HOME/bin/logstash-plugin install gemname. This gem is not a stand-alone program"