Rework DockerBuilderPublisher to work under dockerNode()

src/main/java/com/nirima/jenkins/plugins/docker/DockerCloud.java

@@ -362,6 +362,7 @@ public void run() {
                             // TODO where can we log provisioning progress ?
                             final DockerAPI api = DockerCloud.this.getDockerApi();
                             slave = t.provisionNode(api, TaskListener.NULL);
+                            slave.setDockerAPI(api);
                             slave.setCloudId(DockerCloud.this.name);
                             plannedNode.complete(slave);
 

src/main/java/com/nirima/jenkins/plugins/docker/builder/DockerBuilderPublisher.java

@@ -23,15 +23,18 @@
 import hudson.Launcher;
 import hudson.model.AbstractProject;
 import hudson.model.Item;
+import hudson.model.Node;
 import hudson.model.TaskListener;
 import hudson.remoting.RemoteInputStream;
 import hudson.remoting.VirtualChannel;
+import hudson.remoting.Channel;
 import hudson.slaves.Cloud;
 import hudson.tasks.BuildStepDescriptor;
 import hudson.tasks.Builder;
 import hudson.util.FormValidation;
 import hudson.util.ListBoxModel;
 import io.jenkins.docker.client.DockerAPI;
+import io.jenkins.docker.DockerTransientNode;
 import jenkins.MasterToSlaveFileCallable;
 import jenkins.model.Jenkins;
 import jenkins.tasks.SimpleBuildStep;
@@ -204,15 +207,21 @@ public static void verifyTags(String tagsString) {
         }
     }
 
-    protected DockerCloud getCloud(Launcher launcher) {
+    protected DockerAPI getDockerAPI(Launcher launcher) {
 
         DockerCloud theCloud;
+        VirtualChannel channel = launcher.getChannel();
 
         if (!Strings.isNullOrEmpty(cloud)) {
             theCloud = JenkinsUtils.getServer(cloud);
         } else {
-
-            Optional<DockerCloud> cloud = JenkinsUtils.getCloudForChannel(launcher.getChannel());
+            if(channel instanceof Channel) {
+                Node node = Jenkins.getInstance().getNode(((Channel)channel).getName() );
+                if (node instanceof DockerTransientNode) {
+                    return ((DockerTransientNode) node).getDockerAPI();
+                }
+            }
+            Optional<DockerCloud> cloud = JenkinsUtils.getCloudForChannel(channel);
             if (!cloud.isPresent())
                 throw new RuntimeException("Could not find the cloud this project was built on");
 
@@ -226,13 +235,14 @@ protected DockerCloud getCloud(Launcher launcher) {
             for (DockerCloud dc : JenkinsUtils.getServers()) {
                 if (!dc.isTriton()) {
                     LOGGER.warn("Picked {} cloud instead", dc.getDisplayName());
-                    return dc;
+                    theCloud = dc;
+                    break;
                 }
             }
 
         }
 
-        return theCloud;
+        return theCloud.getDockerApi();
     }
 
     class Run implements Serializable {
@@ -248,14 +258,14 @@ class Run implements Serializable {
 
         final transient hudson.model.Run<?, ?> run;
 
-        private Run(hudson.model.Run<?, ?> run, final Launcher launcher, final TaskListener listener, FilePath fpChild, List<String> tagsToUse, DockerCloud dockerCloud) {
+        private Run(hudson.model.Run<?, ?> run, final Launcher launcher, final TaskListener listener, FilePath fpChild, List<String> tagsToUse, DockerAPI dockerApi) {
 
             this.run = run;
             this.launcher = launcher;
             this.listener = listener;
             this.fpChild = fpChild;
             this.tagsToUse = tagsToUse;
-            this.dockerApi = dockerCloud.getDockerApi();
+            this.dockerApi = dockerApi;
 
         }
 
@@ -424,7 +434,7 @@ public void perform(hudson.model.Run<?, ?> run, FilePath workspace, Launcher lau
         } catch (MacroEvaluationException e) {
             listener.getLogger().println("Couldn't macro expand docker file directory " + dockerFileDirectory);
         }
-        new Run(run, launcher, listener, new FilePath(workspace, expandedDockerFileDirectory), expandedTags, getCloud(launcher)).run();
+        new Run(run, launcher, listener, new FilePath(workspace, expandedDockerFileDirectory), expandedTags, getDockerAPI(launcher)).run();
 
     }
 

src/main/java/io/jenkins/docker/pipeline/DockerNodeStepExecution.java

@@ -92,6 +92,7 @@ private DockerTransientNode createNode(TaskListener listener) {
         Computer computer = null;
         try {
             node = t.provisionNode(api, listener);
+            node.setDockerAPI(api);
             node.setAcceptingTasks(false); // Prevent this node to be used by tasks from build queue
             Jenkins.getInstance().addNode(node);
 

src/test/java/io/jenkins/docker/pipeline/DockerNodeStepTest.java

@@ -259,6 +259,22 @@ public void evaluate() throws Throwable {
         });
     }
 
+    @Test
+    public void dockerBuilderPublisher() throws Exception {
+        story.addStep(new Statement() {
+            @Override
+            public void evaluate() throws Throwable {
+                WorkflowJob j = story.j.jenkins.createProject(WorkflowJob.class, "dockerBuilderPublisher");
+                j.setDefinition(new CpsFlowDefinition("dockerNode(dockerHost: 'unix:///var/run/docker.sock', image: 'jenkins/slave', remoteFs: '/home/jenkins') {\n" +
+                        "  writeFile(file: 'Dockerfile', text: 'FROM jenkins/slave')\n" +
+                        "  step([$class: 'DockerBuilderPublisher', dockerFileDirectory: ''])\n" +
+                        "}\n", true));
+                WorkflowRun r = story.j.buildAndAssertSuccess(j);
+                story.j.assertLogContains("Successfully built", r);
+            }
+        });
+    }
+
     public static class PathModifierStep extends Step {
         private String element;