Offline Gradle: local branches.json fallback

build-tools-internal/src/integTest/groovy/org/elasticsearch/gradle/internal/info/GlobalBuildInfoPluginOfflineBranchesFallbackFuncTest.groovy

@@ -0,0 +1,139 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the "Elastic License
+ * 2.0", the "GNU Affero General Public License v3.0 only", and the "Server Side
+ * Public License v 1"; you may not use this file except in compliance with, at
+ * your election, the "Elastic License 2.0", the "GNU Affero General Public
+ * License v3.0 only", or the "Server Side Public License, v 1".
+ */
+
+package org.elasticsearch.gradle.internal.info
+
+import org.elasticsearch.gradle.fixtures.AbstractGradleFuncTest
+import org.gradle.testkit.runner.TaskOutcome
+
+class GlobalBuildInfoPluginOfflineBranchesFallbackFuncTest extends AbstractGradleFuncTest {
+
+    def setup() {
+        // This plugin reads files from the workspace and performs environment detection
+        // that is not compatible with the configuration cache in functional tests.
+        configurationCacheCompatible = false
+    }
+
+    def "offline mode falls back to local branches.json when present"() {
+        given:
+        writeBwcVersionSource()
+        writeBranchesJson()
+        writeBuildThatResolvesBwcVersions()
+
+        when:
+        def result = gradleRunner(
+            "resolveBwcVersions",
+            "--offline",
+            // Make any accidental outbound HTTPS attempt fail deterministically.
+            "-Dhttps.proxyHost=127.0.0.1",
+            "-Dhttps.proxyPort=1",
+            "-Dhttp.proxyHost=127.0.0.1",
+            "-Dhttp.proxyPort=1",
+            "-DBWC_VERSION_SOURCE=${file("Version.java").absolutePath}"
+        ).build()
+
+        then:
+        result.task(":resolveBwcVersions").outcome == TaskOutcome.SUCCESS
+        assertOutputContains(
+            result.output,
+            "Gradle is running in offline mode; falling back to local branches.json"
+        )
+        assertOutputContains(result.output, "BWC_VERSIONS_RESOLVED")
+    }
+
+    def "offline mode without local branches.json retains failure behavior"() {
+        given:
+        writeBwcVersionSource()
+        // Intentionally do not create branches.json
+        writeBuildThatResolvesBwcVersions()
+
+        when:
+        def result = gradleRunner(
+            "resolveBwcVersions",
+            "--offline",
+            "-Dhttps.proxyHost=127.0.0.1",
+            "-Dhttps.proxyPort=1",
+            "-Dhttp.proxyHost=127.0.0.1",
+            "-Dhttp.proxyPort=1",
+            "-DBWC_VERSION_SOURCE=${file("Version.java").absolutePath}"
+        ).buildAndFail()
+
+        then:
+        assertOutputContains(result.output, "Failed to download branches.json from:")
+        assertOutputMissing(result.output, "falling back to local branches.json")
+    }
+
+    def "non-offline mode does not fall back to local branches.json"() {
+        given:
+        writeBwcVersionSource()
+        writeBranchesJson()
+        writeBuildThatResolvesBwcVersions()
+
+        when:
+        def result = gradleRunner(
+            "resolveBwcVersions",
+            // Not passing --offline on purpose.
+            "-Dhttps.proxyHost=127.0.0.1",
+            "-Dhttps.proxyPort=1",
+            "-Dhttp.proxyHost=127.0.0.1",
+            "-Dhttp.proxyPort=1",
+            "-DBWC_VERSION_SOURCE=${file("Version.java").absolutePath}"
+        ).buildAndFail()
+
+        then:
+        assertOutputContains(result.output, "Failed to download branches.json from:")
+        assertOutputMissing(result.output, "falling back to local branches.json")
+    }
+
+    private void writeBuildThatResolvesBwcVersions() {
+        buildFile.text = """
+            plugins {
+              id 'elasticsearch.global-build-info'
+            }
+
+            tasks.register("resolveBwcVersions") {
+              doLast {
+                // Force bwcVersions resolution, which triggers branches.json loading.
+                def bwcVersions = buildParams.bwcVersionsProvider.get()
+                println "BWC_VERSIONS_RESOLVED=[" + bwcVersions + "]"
+              }
+            }
+        """
+    }
+
+    private void writeBranchesJson() {
+        file("branches.json").text = """\
+            {
+              "branches": [
+                { "branch": "main", "version": "9.1.0" },
+                { "branch": "9.0", "version": "9.0.0" }
+              ]
+            }
+        """.stripIndent()
+    }
+
+    private void writeBwcVersionSource() {
+        // This file is parsed via regex; version constants must have a non-word
+        // character before `public` and must end with `);` to match the pattern.
+        file("Version.java").text = """\
+package org.elasticsearch;
+
+public class Version {
+  // Only used by GlobalBuildInfoPlugin in tests via regex parsing.
+   public static final Version V_9_0_0 = Version.fromId(9000000);
+   public static final Version V_9_1_0 = Version.fromId(9010000);
+
+  private static Version fromId(int id) {
+    return new Version();
+  }
+}
+"""
+    }
+}
+

build-tools-internal/src/main/java/org/elasticsearch/gradle/internal/info/GlobalBuildInfoPlugin.java

@@ -214,9 +214,24 @@ private List<Version> parseVersionLines(List<String> versionLines) {
     }
 
     private List<DevelopmentBranch> getDevelopmentBranches() {
-        String branchesFileLocation = project.getProviders()
-            .gradleProperty(BRANCHES_FILE_LOCATION_PROPERTY)
-            .getOrElse(DEFAULT_BRANCHES_FILE_URL);
+        Provider<String> branchesFileLocationProperty = project.getProviders().gradleProperty(BRANCHES_FILE_LOCATION_PROPERTY);
+        boolean hasExplicitBranchesFileLocation = branchesFileLocationProperty.isPresent();
+        String branchesFileLocation = hasExplicitBranchesFileLocation ? branchesFileLocationProperty.get() : DEFAULT_BRANCHES_FILE_URL;
+        if (hasExplicitBranchesFileLocation == false
+            && project.getGradle().getStartParameter().isOffline()
+            && branchesFileLocation.startsWith("http")) {
+            File localBranchesFile = new File(Util.locateElasticsearchWorkspace(project.getGradle()), "branches.json");
+            if (localBranchesFile.isFile()) {
+                LOGGER.warn(
+                    "Gradle is running in offline mode; falling back to local branches.json at [{}] instead of downloading from [{}]. "
+                        + "To override, set Gradle property [{}].",
+                    localBranchesFile.getAbsolutePath(),
+                    branchesFileLocation,
+                    BRANCHES_FILE_LOCATION_PROPERTY
+                );
+                branchesFileLocation = localBranchesFile.getAbsolutePath();
+            }
+        }
         LOGGER.info("Reading branches.json from {}", branchesFileLocation);
         byte[] branchesBytes;
         if (branchesFileLocation.startsWith("http")) {

build-tools-internal/src/test/java/org/elasticsearch/gradle/internal/EmptyDirTaskTests.java

@@ -15,6 +15,10 @@
 
 import java.io.File;
 import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.attribute.PosixFilePermission;
+import java.util.Collections;
+import java.util.Set;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
@@ -61,9 +65,8 @@ public void testCreateEmptyDirNoPermissions() throws Exception {
 
         assertTrue(newEmptyFolder.exists());
         assertTrue(newEmptyFolder.isDirectory());
-        assertFalse(newEmptyFolder.canExecute());
-        assertFalse(newEmptyFolder.canRead());
-        assertFalse(newEmptyFolder.canWrite());
+        Set<PosixFilePermission> permissions = Files.getPosixFilePermissions(newEmptyFolder.toPath());
+        assertEquals(Collections.emptySet(), permissions);
 
         // cleanup
         newEmptyFolder.delete();