Override Default Distribution Download Url with Custom Distribution Url when it is passed from Plugin

DEVELOPER_GUIDE.md

@@ -33,6 +33,8 @@
       - [runtimeOnly](#runtimeonly)
       - [compileOnly](#compileonly)
       - [testImplementation](#testimplementation)
+    - [Gradle Plugins](#gradle-plugins)
+      - [Distribution Download Plugin](#distribution-download-plugin)
   - [Misc](#misc)
     - [git-secrets](#git-secrets)
       - [Installation](#installation)
@@ -361,6 +363,16 @@ somehow. OpenSearch plugins use this configuration to include dependencies that
 Code that is on the classpath for compiling tests that are part of this project but not production code. The canonical example
 of this is `junit`.
 
+### Gradle Plugins
+
+#### Distribution Download Plugin
+
+The Distribution Download plugin downloads the latest version of OpenSearch by default, and supports overriding this behavior by setting `customDistributionUrl`.
+```
+./gradlew integTest -PcustomDistributionUrl="https://ci.opensearch.org/ci/dbc/bundle-build/1.2.0/1127/linux/x64/dist/opensearch-1.2.0-linux-x64.tar.gz"
+```
+
+
 ## Misc
 
 ### git-secrets

buildSrc/src/main/java/org/opensearch/gradle/DistributionDownloadPlugin.java

@@ -195,15 +195,22 @@ private static void setupDownloadServiceRepo(Project project) {
         if (project.getRepositories().findByName(DOWNLOAD_REPO_NAME) != null) {
             return;
         }
-        addIvyRepo(
-            project,
-            DOWNLOAD_REPO_NAME,
-            "https://artifacts.opensearch.org",
-            FAKE_IVY_GROUP,
-            "/releases" + RELEASE_PATTERN_LAYOUT,
-            "/release-candidates" + RELEASE_PATTERN_LAYOUT
-        );
-        addIvyRepo(project, SNAPSHOT_REPO_NAME, "https://artifacts.opensearch.org", FAKE_SNAPSHOT_IVY_GROUP, SNAPSHOT_PATTERN_LAYOUT);
+        Object customDistributionUrl = project.findProperty("customDistributionUrl");
+        // checks if custom Distribution Url has been passed by user from plugins
+        if (customDistributionUrl != null) {
+            addIvyRepo(project, DOWNLOAD_REPO_NAME, customDistributionUrl.toString(), FAKE_IVY_GROUP, "");
+            addIvyRepo(project, SNAPSHOT_REPO_NAME, customDistributionUrl.toString(), FAKE_SNAPSHOT_IVY_GROUP, "");
+        } else {
+            addIvyRepo(
+                project,
+                DOWNLOAD_REPO_NAME,
+                "https://artifacts.opensearch.org",
+                FAKE_IVY_GROUP,
+                "/releases" + RELEASE_PATTERN_LAYOUT,
+                "/release-candidates" + RELEASE_PATTERN_LAYOUT
+            );
+            addIvyRepo(project, SNAPSHOT_REPO_NAME, "https://artifacts.opensearch.org", FAKE_SNAPSHOT_IVY_GROUP, SNAPSHOT_PATTERN_LAYOUT);
+        }
 
         addIvyRepo2(project, DOWNLOAD_REPO_NAME_ES, "https://artifacts-no-kpi.elastic.co", FAKE_IVY_GROUP_ES);
         addIvyRepo2(project, SNAPSHOT_REPO_NAME_ES, "https://snapshots-no-kpi.elastic.co", FAKE_SNAPSHOT_IVY_GROUP_ES);

buildSrc/src/test/java/org/opensearch/gradle/DistributionDownloadPluginTests.java

@@ -32,6 +32,7 @@
 
 package org.opensearch.gradle;
 
+import org.gradle.api.internal.artifacts.repositories.DefaultIvyArtifactRepository;
 import org.opensearch.gradle.OpenSearchDistribution.Platform;
 import org.opensearch.gradle.OpenSearchDistribution.Type;
 import org.opensearch.gradle.info.BuildParams;
@@ -79,6 +80,59 @@ public void testVersionDefault() {
         assertEquals(distro.getVersion(), VersionProperties.getOpenSearch());
     }
 
+    public void testCustomDistributionUrlWithUrl() {
+        Project project = ProjectBuilder.builder().build();
+        String customUrl = "https://artifacts.opensearch.org/custom";
+        project.getExtensions().getExtraProperties().set("customDistributionUrl", customUrl);
+        DistributionDownloadPlugin plugin = new DistributionDownloadPlugin();
+        plugin.apply(project);
+        assertEquals(4, project.getRepositories().size());
+        assertEquals(
+            ((DefaultIvyArtifactRepository) project.getRepositories().getAt("opensearch-downloads")).getUrl().toString(),
+            customUrl
+        );
+        assertEquals(
+            ((DefaultIvyArtifactRepository) project.getRepositories().getAt("opensearch-snapshots")).getUrl().toString(),
+            customUrl
+        );
+        assertEquals(
+            ((DefaultIvyArtifactRepository) project.getRepositories().getAt("elasticsearch-downloads")).getUrl().toString(),
+            "https://artifacts-no-kpi.elastic.co"
+        );
+        assertEquals(
+            ((DefaultIvyArtifactRepository) project.getRepositories().getAt("elasticsearch-snapshots")).getUrl().toString(),
+            "https://snapshots-no-kpi.elastic.co"
+        );
+
+    }
+
+    public void testCustomDistributionUrlWithoutUrl() {
+        Project project = ProjectBuilder.builder().build();
+        DistributionDownloadPlugin plugin = new DistributionDownloadPlugin();
+        plugin.apply(project);
+        assertEquals(5, project.getRepositories().size());
+        assertEquals(
+            ((DefaultIvyArtifactRepository) project.getRepositories().getAt("opensearch-downloads")).getUrl().toString(),
+            "https://artifacts.opensearch.org"
+        );
+        assertEquals(
+            ((DefaultIvyArtifactRepository) project.getRepositories().getAt("opensearch-downloads2")).getUrl().toString(),
+            "https://artifacts.opensearch.org"
+        );
+        assertEquals(
+            ((DefaultIvyArtifactRepository) project.getRepositories().getAt("opensearch-snapshots")).getUrl().toString(),
+            "https://artifacts.opensearch.org"
+        );
+        assertEquals(
+            ((DefaultIvyArtifactRepository) project.getRepositories().getAt("elasticsearch-downloads")).getUrl().toString(),
+            "https://artifacts-no-kpi.elastic.co"
+        );
+        assertEquals(
+            ((DefaultIvyArtifactRepository) project.getRepositories().getAt("elasticsearch-snapshots")).getUrl().toString(),
+            "https://snapshots-no-kpi.elastic.co"
+        );
+    }
+
     public void testBadVersionFormat() {
         assertDistroError(
             createProject(null, false),