Publish snapshot to maven.

Signed-off-by: dblock <dblock@amazon.com>

java-client/build.gradle.kts

@@ -248,8 +248,15 @@ tasks.withType<Jar> {
 
 publishing {
     repositories{
-        maven {
-            url = uri("${rootProject.buildDir}/repository")
+        if (version.toString().endsWith("SNAPSHOT")) {
+            maven("https://aws.oss.sonatype.org/content/repositories/snapshots/") {
+                name = "snapshots"
+                credentials(PasswordCredentials::class)
+            }
+        } else {
+            maven {
+                uri("${rootProject.buildDir}/repository")
+            }
         }
     }
     publications {

jenkins/publish-snapshot.jenkinsfile

@@ -0,0 +1,25 @@
+pipeline {
+    agent {
+        docker {
+            label 'Jenkins-Agent-AL2-X64-C54xlarge-Docker-Host'
+            image 'opensearchstaging/ci-runner:ci-runner-centos7-opensearch-build-v2'
+            args '-e JAVA_HOME=/opt/java/openjdk-11'
+            alwaysPull true
+        }
+    }
+    stages {
+        stage('Publish to Maven Staging') {
+            steps {
+                git url: 'https://github.com/opensearch-project/opensearch-java.git', branch: 'main'
+                withCredentials([usernamePassword(credentialsId: 'Sonatype', usernameVariable: 'ORG_GRADLE_PROJECT_snapshotsUsername', passwordVariable: 'ORG_GRADLE_PROJECT_snapshotsPassword')]) {
+                    sh './gradlew --no-daemon publishPublishMavenPublicationToSnapshotsRepository'
+                }
+            }
+            post() {
+                always {
+                    cleanWs disableDeferredWipeout: true, deleteDirs: true
+                }
+            }
+        }
+    }
+}