Add getDockerHost() to DockerProvider

Author: intisy

src/main/java/io/github/intisy/docker/DockerProvider.java

@@ -137,6 +137,24 @@ public static DockerProvider get() {
      */
     public abstract void ensureInstalled() throws IOException;
 
+    /**
+     * Get the Docker host URL for connecting to this provider's Docker daemon.
+     * This can be used as the {@code DOCKER_HOST} environment variable or passed
+     * to other tools that need to connect to this Docker instance.
+     * <p>
+     * Returns values like:
+     * <ul>
+     *   <li>{@code unix:///path/to/docker.sock} (Linux)</li>
+     *   <li>{@code npipe:////./pipe/docker_java_abc123} (Windows native)</li>
+     *   <li>{@code tcp://localhost:2375} (macOS Lima, Windows WSL2)</li>
+     * </ul>
+     * <p>
+     * Must be called after {@link #start()}.
+     *
+     * @return The Docker host URL string
+     */
+    public abstract String getDockerHost();
+
     /**
      * Check if NVIDIA GPU is available on this system.
      * @return true if an NVIDIA GPU is detected, false otherwise

src/main/java/io/github/intisy/docker/LinuxDockerProvider.java

@@ -226,6 +226,11 @@ public void start() throws IOException, InterruptedException {
         log.info("Docker daemon started (instance: {})", instanceId);
     }
 
+    @Override
+    public String getDockerHost() {
+        return "unix://" + dockerSocketPath.toString();
+    }
+
     @Override
     public DockerClient getClient() {
         if (this.dockerClient == null) {

src/main/java/io/github/intisy/docker/MacDockerProvider.java

@@ -436,6 +436,11 @@ private boolean waitForDocker() throws InterruptedException {
         return false;
     }
 
+    @Override
+    public String getDockerHost() {
+        return "tcp://localhost:" + dockerPort;
+    }
+
     @Override
     public DockerClient getClient() {
         if (this.dockerClient == null) {

src/main/java/io/github/intisy/docker/WindowsDockerProvider.java

@@ -750,6 +750,16 @@ private boolean isWsl2Available() {
 
     private String wslIpAddress;
 
+    @Override
+    public String getDockerHost() {
+        if (usingWsl2) {
+            String host = wslIpAddress != null ? wslIpAddress : "localhost";
+            return "tcp://" + host + ":" + dockerPort;
+        } else {
+            return "npipe://" + dockerPipePath.toString().replace("\\", "/");
+        }
+    }
+
     @Override
     public DockerClient getClient() {
         if (this.dockerClient == null) {