Add draft ItemConfigurator support for WorkflowJob

pom.xml

@@ -189,6 +189,19 @@
       <classifier>tests</classifier>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>io.jenkins</groupId>
+      <artifactId>configuration-as-code</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>io.jenkins.configuration-as-code</groupId>
+      <artifactId>test-harness</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>org.jenkins-ci.plugins.workflow</groupId>
+      <artifactId>workflow-cps</artifactId>
+      <scope>compile</scope>
+    </dependency>
   </dependencies>
   <repositories>
     <repository>

src/main/java/org/jenkinsci/plugins/workflow/job/PipelineItemConfigurator.java

@@ -0,0 +1,60 @@
+package org.jenkinsci.plugins.workflow.job;
+
+import hudson.Extension;
+import hudson.model.Descriptor;
+import io.jenkins.plugins.casc.ConfigurationContext;
+import io.jenkins.plugins.casc.ConfiguratorException;
+import io.jenkins.plugins.casc.ItemConfigurator;
+import io.jenkins.plugins.casc.model.CNode;
+import io.jenkins.plugins.casc.model.Mapping;
+import jenkins.model.Jenkins;
+import org.jenkinsci.plugins.workflow.cps.CpsFlowDefinition;
+
+import java.io.IOException;
+
+@Extension
+public class PipelineItemConfigurator implements ItemConfigurator<WorkflowJob> {
+
+	@Override
+	public String getName() {
+		return "pipeline";
+	}
+
+	@Override
+	public Class<WorkflowJob> getTarget() {
+		return WorkflowJob.class;
+	}
+
+	@Override
+	public WorkflowJob configure(String name, CNode config, ConfigurationContext context) throws ConfiguratorException {
+		try {
+			Jenkins jenkins = Jenkins.get();
+			WorkflowJob job = (WorkflowJob) jenkins.getItem(name);
+
+			if (job == null) {
+				job = jenkins.createProject(WorkflowJob.class, name);
+			}
+
+			Mapping mapping = config.asMapping();
+
+			if (mapping.containsKey("description")) {
+				job.setDescription(mapping.getScalarValue("description"));
+			}
+
+			CNode definitionNode = mapping.get("definition");
+			if (definitionNode != null) {
+				Mapping defMapping = definitionNode.asMapping();
+				if (defMapping.containsKey("cps")) {
+					String script = defMapping.get("cps").asMapping().getScalarValue("script");
+					job.setDefinition(new CpsFlowDefinition(script, true));
+				}
+			}
+
+			job.save();
+			return job;
+
+		} catch (IOException | Descriptor.FormException e) {
+			throw new ConfiguratorException("Failed to configure pipeline: " + name, e);
+		}
+	}
+}

src/test/java/org/jenkinsci/plugins/workflow/job/PipelineItemConfiguratorTest.java

@@ -0,0 +1,55 @@
+package org.jenkinsci.plugins.workflow.job;
+
+import io.jenkins.plugins.casc.ConfigurationAsCode;
+import io.jenkins.plugins.casc.misc.ConfiguredWithCode;
+import io.jenkins.plugins.casc.misc.JenkinsConfiguredWithCodeRule;
+import jenkins.model.Jenkins;
+import org.jenkinsci.plugins.workflow.cps.CpsFlowDefinition;
+import org.junit.Rule;
+import org.junit.Test;
+
+import java.util.Objects;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+
+public class PipelineItemConfiguratorTest {
+
+	@Rule
+	public JenkinsConfiguredWithCodeRule j = new JenkinsConfiguredWithCodeRule();
+
+	@Test
+	@ConfiguredWithCode("create-pipeline.yaml")
+	public void shouldCreateNewPipeline() {
+		WorkflowJob job = (WorkflowJob) Jenkins.get().getItem("my-new-pipeline");
+
+		assertNotNull("Pipeline job should have been created by JCasC", job);
+		assertEquals("A brand new pipeline created by JCasC", job.getDescription());
+
+		assertTrue("Definition should be CpsFlowDefinition", job.getDefinition() instanceof CpsFlowDefinition);
+		CpsFlowDefinition definition = (CpsFlowDefinition) job.getDefinition();
+		assertEquals("node { echo 'Hello, JCasC!' }", definition.getScript());
+		assertTrue("Sandbox should be true", definition.isSandbox());
+	}
+
+	@Test
+	public void shouldUpdateExistingPipeline() throws Exception {
+		WorkflowJob existingJob = j.jenkins.createProject(WorkflowJob.class, "existing-pipeline");
+		existingJob.setDescription("Old Description");
+		existingJob.setDefinition(new CpsFlowDefinition("node { echo 'Old script' }", false));
+
+		ConfigurationAsCode.get().configure(
+			Objects.requireNonNull(getClass().getResource("update-pipeline.yaml")).toExternalForm()
+		);
+
+		WorkflowJob updatedJob = (WorkflowJob) Jenkins.get().getItem("existing-pipeline");
+
+		assertNotNull(updatedJob);
+		assertEquals("Updated description via JCasC", updatedJob.getDescription());
+
+		CpsFlowDefinition definition = (CpsFlowDefinition) updatedJob.getDefinition();
+		assertEquals("node { echo 'Updated script!' }", definition.getScript());
+		assertTrue("Sandbox should be reset to true", definition.isSandbox());
+	}
+}

src/test/resources/org/jenkinsci/plugins/workflow/job/create-pipeline.yaml

@@ -0,0 +1,7 @@
+items:
+  - pipeline:
+      name: "my-new-pipeline"
+      description: "A brand new pipeline created by JCasC"
+      definition:
+        cps:
+          script: "node { echo 'Hello, JCasC!' }"

src/test/resources/org/jenkinsci/plugins/workflow/job/update-pipeline.yaml

@@ -0,0 +1,7 @@
+items:
+  - pipeline:
+      name: "existing-pipeline"
+      description: "Updated description via JCasC"
+      definition:
+        cps:
+          script: "node { echo 'Updated script!' }"