Adds log4j configuration for telemetry-otel plugin (#8393)

* Adds log4j configuration for telemetry-otel plugin

Signed-off-by: Gagan Juneja <gjjuneja@amazon.com>

* Updates changelog

Signed-off-by: Gagan Juneja <gjjuneja@amazon.com>

* Fixes spotless

Signed-off-by: Gagan Juneja <gjjuneja@amazon.com>

---------

Signed-off-by: Gagan Juneja <gjjuneja@amazon.com>
Co-authored-by: Gagan Juneja <gjjuneja@amazon.com>

CHANGELOG.md

@@ -76,6 +76,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Support OpenSSL Provider with default Netty allocator ([#5460](https://github.com/opensearch-project/OpenSearch/pull/5460))
 - Replaces ZipInputStream with ZipFile to fix Zip Slip vulnerability ([#7230](https://github.com/opensearch-project/OpenSearch/pull/7230))
 - Add missing validation/parsing of SearchBackpressureMode of SearchBackpressureSettings ([#7541](https://github.com/opensearch-project/OpenSearch/pull/7541))
+- Adds log4j configuration for telemetry LogSpanExporter ([#8393](https://github.com/opensearch-project/OpenSearch/pull/8393))
 
 ### Security
 

plugins/telemetry-otel/build.gradle

@@ -54,3 +54,25 @@ thirdPartyAudit {
     'io.opentelemetry.sdk.autoconfigure.spi.traces.ConfigurableSpanExporterProvider'
   )
 }
+
+tasks.named("bundlePlugin").configure {
+  from('config/telemetry-otel') {
+    into 'config'
+  }
+}
+
+tasks.register("writeTestJavaPolicy") {
+  doLast {
+    final File tmp = file("${buildDir}/tmp")
+    if (tmp.exists() == false && tmp.mkdirs() == false) {
+      throw new GradleException("failed to create temporary directory [${tmp}]")
+    }
+    final File javaPolicy = file("${tmp}/java.policy")
+    javaPolicy.write(
+      [
+        "grant {",
+        "  permission java.io.FilePermission \"config\", \"read\";",
+        "};"
+      ].join("\n"))
+  }
+}

plugins/telemetry-otel/config/telemetry-otel/log4j2.properties

@@ -0,0 +1,27 @@
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+# The OpenSearch Contributors require contributions made to
+# this file be licensed under the Apache-2.0 license or a
+# compatible open source license.
+#
+
+
+appender.tracing.type = RollingFile
+appender.tracing.name = tracing
+appender.tracing.fileName = ${sys:opensearch.logs.base_path}${sys:file.separator}${sys:opensearch.logs.cluster_name}_otel_traces.log
+appender.tracing.filePermissions = rw-r-----
+appender.tracing.layout.type = PatternLayout
+appender.tracing.layout.pattern = %m%n
+appender.tracing.filePattern = ${sys:opensearch.logs.base_path}${sys:file.separator}${sys:opensearch.logs.cluster_name}_otel_traces-%i.log.gz
+appender.tracing.policies.type = Policies
+appender.tracing.policies.size.type = SizeBasedTriggeringPolicy
+appender.tracing.policies.size.size = 1GB
+appender.tracing.strategy.type = DefaultRolloverStrategy
+appender.tracing.strategy.max = 4
+
+
+logger.exporter.name = io.opentelemetry.exporter.logging.LoggingSpanExporter
+logger.exporter.level = INFO
+logger.exporter.appenderRef.tracing.ref = tracing
+logger.exporter.additivity = false

plugins/telemetry-otel/src/main/java/org/opensearch/telemetry/tracing/OTelResourceProvider.java

@@ -42,7 +42,7 @@ private OTelResourceProvider() {}
     public static OpenTelemetry get(Settings settings) {
         return get(
             settings,
-            new LoggingSpanExporter(),
+            LoggingSpanExporter.create(),
             ContextPropagators.create(W3CTraceContextPropagator.getInstance()),
             Sampler.alwaysOn()
         );