Refactor Docker Compose version detection to predictably pick v2 only if v1 is not available

buildSrc/src/main/java/org/opensearch/gradle/docker/DockerSupportService.java

@@ -105,16 +105,15 @@
             Result lastResult = null;
             Version version = null;
             boolean isVersionHighEnough = false;
-            boolean isComposeAvailable = false;
-            boolean isComposeV2Available = false;
+            DockerComposeAvailability dockerComposeAvailability = null;
 
             // Check if the Docker binary exists
             final Optional<String> dockerBinary = getDockerPath();
             if (isExcludedOs() == false && dockerBinary.isPresent()) {
                 dockerPath = dockerBinary.get();
 
                 // Since we use a multi-stage Docker build, check the Docker version meets minimum requirement
-                lastResult = runCommand(dockerPath, "version", "--format", "{{.Server.Version}}");
+                lastResult = runCommand(execOperations, dockerPath, "version", "--format", "{{.Server.Version}}");
 
                 if (lastResult.isSuccess()) {
                     version = Version.fromString(lastResult.stdout.trim(), Version.Mode.RELAXED);
@@ -123,15 +122,11 @@
 
                     if (isVersionHighEnough) {
                         // Check that we can execute a privileged command
-                        lastResult = runCommand(dockerPath, "images");
-
+                        lastResult = runCommand(execOperations, dockerPath, "images");
                         // If docker all checks out, see if docker-compose is available and working
-                        Optional<String> composePath = getDockerComposePath();
-                        if (lastResult.isSuccess() && composePath.isPresent()) {
-                            isComposeAvailable = runCommand(composePath.get(), "version").isSuccess();
+                        if (lastResult.isSuccess()) {
+                            dockerComposeAvailability = DockerComposeAvailability.detect(execOperations, dockerPath).orElse(null);
                         }
-
-                        isComposeV2Available = runCommand(dockerPath, "compose", "version").isSuccess();
                     }
                 }
             }
@@ -140,8 +135,7 @@
 
             this.dockerAvailability = new DockerAvailability(
                 isAvailable,
-                isComposeAvailable,
-                isComposeV2Available,
+                dockerComposeAvailability,
                 isVersionHighEnough,
                 dockerPath,
                 version,
@@ -291,17 +285,6 @@
         return Arrays.asList(DOCKER_BINARIES).stream().filter(path -> new File(path).exists()).findFirst();
     }
 
-    /**
-     * Searches the entries in {@link #DOCKER_COMPOSE_BINARIES} for the Docker Compose CLI. This method does
-     * not check whether the installation appears usable, see {@link #getDockerAvailability()} instead.
-     *
-     * @return the path to a CLI, if available.
-     */
-    private Optional<String> getDockerComposePath() {
-        // Check if the Docker binary exists
-        return Arrays.asList(DOCKER_COMPOSE_BINARIES).stream().filter(path -> new File(path).exists()).findFirst();
-    }
-
     private void throwDockerRequiredException(final String message) {
         throwDockerRequiredException(message, null);
     }
@@ -321,7 +304,7 @@
      * while running the command, or the process was killed after reaching the 10s timeout,
      * then the exit code will be -1.
      */
-    private Result runCommand(String... args) {
+    private static Result runCommand(ExecOperations execOperations, String... args) {
         if (args.length == 0) {
             throw new IllegalArgumentException("Cannot execute with no command");
         }
@@ -356,14 +339,9 @@
         public final boolean isAvailable;
 
         /**
-         * True if docker-compose is available.
+         * Non-null if docker-compose v1 or v2 is available.
          */
-        public final boolean isComposeAvailable;
-
-        /**
-         * True if docker compose is available.
-         */
-        public final boolean isComposeV2Available;
+        public final DockerComposeAvailability dockerComposeAvailability;
 
         /**
          * True if the installed Docker version is &gt;= 17.05
@@ -387,23 +365,70 @@
 
         DockerAvailability(
             boolean isAvailable,
-            boolean isComposeAvailable,
-            boolean isComposeV2Available,
+            DockerComposeAvailability dockerComposeAvailability,
             boolean isVersionHighEnough,
             String path,
             Version version,
             Result lastCommand
         ) {
             this.isAvailable = isAvailable;
-            this.isComposeAvailable = isComposeAvailable;
-            this.isComposeV2Available = isComposeV2Available;
+            this.dockerComposeAvailability = dockerComposeAvailability;
             this.isVersionHighEnough = isVersionHighEnough;
             this.path = path;
             this.version = version;
             this.lastCommand = lastCommand;
         }
+
+        public boolean isDockerComposeAvailable() {
+            return dockerComposeAvailability != null;
+        }
+    }
+
+    /**
+     * Marker interface for Docker Compose availability
+     */
+    private interface DockerComposeAvailability {
+        /**
+         * Detects Docker Compose V1/V2 availability
+         */
+        private static Optional<DockerComposeAvailability> detect(ExecOperations execOperations, String dockerPath) {
+            Optional<String> composePath = getDockerComposePath();
+            if (composePath.isPresent()) {
+                if (runCommand(execOperations, composePath.get(), "version").isSuccess()) {
+                    return Optional.of(new DockerComposeV1Availability());
+                }
+            }
+
+            if (runCommand(execOperations, dockerPath, "compose", "version").isSuccess()) {
+                return Optional.of(new DockerComposeV2Availability());
+            }
+
+            return Optional.empty();
+        }
+
+        /**
+         * Searches the entries in {@link #DOCKER_COMPOSE_BINARIES} for the Docker Compose CLI. This method does
+         * not check whether the installation appears usable, see {@link #getDockerAvailability()} instead.
+         *
+         * @return the path to a CLI, if available.
+         */
+        private static Optional<String> getDockerComposePath() {
+            // Check if the Docker binary exists
+            return Arrays.asList(DOCKER_COMPOSE_BINARIES).stream().filter(path -> new File(path).exists()).findFirst();
+        }
+
     }
 
+    /**
+     * Docker Compose V1 availability
+     */
+    public static class DockerComposeV1Availability implements DockerComposeAvailability {}
+
+    /**
+     * Docker Compose V2 availability
+     */
+    public static class DockerComposeV2Availability implements DockerComposeAvailability {}
+
     /**
      * This class models the result of running a command. It captures the exit code, standard output and standard error.
      */

buildSrc/src/main/java/org/opensearch/gradle/testfixtures/TestFixturesPlugin.java

@@ -43,6 +43,7 @@
 import org.opensearch.gradle.SystemPropertyCommandLineArgumentProvider;
 import org.opensearch.gradle.docker.DockerSupportPlugin;
 import org.opensearch.gradle.docker.DockerSupportService;
+import org.opensearch.gradle.docker.DockerSupportService.DockerComposeV2Availability;
 import org.opensearch.gradle.info.BuildParams;
 import org.opensearch.gradle.precommit.TestingConventionsTasks;
 import org.opensearch.gradle.util.GradleUtils;
@@ -171,11 +172,8 @@
                 .findFirst();
 
             composeExtension.getExecutable().set(dockerCompose.isPresent() ? dockerCompose.get() : "/usr/bin/docker");
-            if (dockerSupport.get().getDockerAvailability().isComposeV2Available) {
-                composeExtension.getUseDockerComposeV2().set(true);
-            } else if (dockerSupport.get().getDockerAvailability().isComposeAvailable) {
-                composeExtension.getUseDockerComposeV2().set(false);
-            }
+            composeExtension.getUseDockerComposeV2()
+                .set(dockerSupport.get().getDockerAvailability().dockerComposeAvailability instanceof DockerComposeV2Availability);
 
             tasks.named("composeUp").configure(t -> {
                 // Avoid running docker-compose tasks in parallel in CI due to some issues on certain Linux distributions
@@ -232,8 +230,7 @@
 
     private void maybeSkipTask(Provider<DockerSupportService> dockerSupport, Task task) {
         task.onlyIf(spec -> {
-            boolean isComposeAvailable = dockerSupport.get().getDockerAvailability().isComposeV2Available
-                || dockerSupport.get().getDockerAvailability().isComposeAvailable;
+            boolean isComposeAvailable = dockerSupport.get().getDockerAvailability().isDockerComposeAvailable();
             if (isComposeAvailable == false) {
                 LOGGER.info("Task {} requires docker-compose but it is unavailable. Task will be skipped.", task.getPath());
             }