feat: adding dry run mode (refs #300)

README.md

@@ -76,6 +76,18 @@ The token can be supplied as a:
 
   `curl -vs -H "Authorization: Bearer abc123" "http://localhost:8080/jenkins/generic-webhook-trigger/invoke" 2>&1`
 
+## Dry run
+
+The dry run feature enables a user to test the plugin without actually triggering any jobs.
+
+Dry run is enabled by supplying the `gwt-dry-run: true` header.
+
+```sh
+curl -v -H "gwt-dry-run: true"\
+  "http://localhost:8080/jenkins/generic-webhook-trigger/invoke?token=abc123"
+```
+
+
 ## Cache jobs
 
 When plugin is used in large installations it may need some time to retrieve all configured jobs. This can be cached by enabling it in the global configuration. When enabled, the plugin will cache configured jobs for a configured time. The plugin will automatically refresh the cache so that any calls will use the cached value. This means the effect of any changes to any configured job will be delayed.

src/main/java/org/jenkinsci/plugins/gwt/GenericTrigger.java

@@ -29,6 +29,8 @@
 
 public class GenericTrigger extends Trigger<Job<?, ?>> {
 
+  public static final String HEADER_DRY_RUN = "gwt-dry-run";
+
   private List<GenericVariable> genericVariables = newArrayList();
   private String regexpFilterText;
   private String regexpFilterExpression;
@@ -204,7 +206,9 @@ public GenericTriggerResults trigger(
     final String renderedRegexpFilterText = renderText(this.regexpFilterText, resolvedVariables);
     final boolean isMatching = isMatching(renderedRegexpFilterText, this.regexpFilterExpression);
 
-    hudson.model.Queue.Item item = null;
+    String url = null;
+    long id = 0;
+    boolean triggered = false;
     if (isMatching) {
       final String cause = renderText(this.causeString, resolvedVariables);
       final GenericCause genericCause =
@@ -219,12 +223,40 @@ public GenericTriggerResults trigger(
       final ParametersAction parameters =
           createParameterAction(
               parametersDefinitionProperty, resolvedVariables, this.allowSeveralTriggersPerBuild);
-      item =
-          this.retrieveScheduleJob(this.job) //
-              .scheduleBuild2(this.job, quietPeriod, new CauseAction(genericCause), parameters);
+      if (!isDryRun(headers)) {
+        final hudson.model.Queue.Item item =
+            this.retrieveScheduleJob(this.job) //
+                .scheduleBuild2(this.job, quietPeriod, new CauseAction(genericCause), parameters);
+        url = item.getUrl();
+        id = item.getId();
+      } else {
+        url = this.job.getAbsoluteUrl();
+      }
+      triggered = true;
     }
     return new GenericTriggerResults(
-        item, resolvedVariables, renderedRegexpFilterText, this.regexpFilterExpression);
+        url,
+        id,
+        triggered,
+        resolvedVariables,
+        renderedRegexpFilterText,
+        this.regexpFilterExpression);
+  }
+
+  static boolean isDryRun(final Map<String, List<String>> headers) {
+    if (headers == null) {
+      return false;
+    }
+    final List<String> dryRunHeaders = headers.get(HEADER_DRY_RUN);
+    if (dryRunHeaders == null) {
+      return false;
+    }
+    for (final String dryRunHeader : dryRunHeaders) {
+      if (dryRunHeader.equalsIgnoreCase("true")) {
+        return true;
+      }
+    }
+    return false;
   }
 
   @SuppressWarnings("rawtypes")

src/main/java/org/jenkinsci/plugins/gwt/GenericTriggerResults.java

@@ -12,46 +12,41 @@ public class GenericTriggerResults {
   private final boolean triggered;
 
   public GenericTriggerResults(
-      final hudson.model.Queue.Item item,
+      final String url,
+      final long id,
+      final boolean triggered,
       final Map<String, String> resolvedVariables,
       final String regexpFilterText,
       final String regexpFilterExpression) {
-    if (item != null) {
-      this.url = item.getUrl();
-      this.id = item.getId();
-      this.triggered = true;
-    } else {
-      this.url = null;
-      this.id = 0;
-      this.triggered = false;
-    }
-
+    this.url = url;
+    this.id = id;
+    this.triggered = triggered;
     this.resolvedVariables = resolvedVariables;
     this.regexpFilterText = regexpFilterText;
     this.regexpFilterExpression = regexpFilterExpression;
   }
 
   public boolean isTriggered() {
-    return triggered;
+    return this.triggered;
   }
 
   public long getId() {
-    return id;
+    return this.id;
   }
 
   public String getUrl() {
-    return url;
+    return this.url;
   }
 
   public String getRegexpFilterExpression() {
-    return regexpFilterExpression;
+    return this.regexpFilterExpression;
   }
 
   public String getRegexpFilterText() {
-    return regexpFilterText;
+    return this.regexpFilterText;
   }
 
   public Map<String, String> getResolvedVariables() {
-    return resolvedVariables;
+    return this.resolvedVariables;
   }
 }

src/test/java/org/jenkinsci/plugins/gwt/GenericTriggerResultsTest.java

@@ -1,43 +1,40 @@
 package org.jenkinsci.plugins.gwt;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.mockito.Mockito.mock;
-import static org.mockito.Mockito.when;
 
-import hudson.model.Queue.Item;
 import java.util.Map;
 import org.junit.Test;
 
 public class GenericTriggerResultsTest {
   @Test
   public void testNull() {
-    final Item item = null;
+    final String url = null;
+    final long id = 0;
+    final boolean triggered = false;
     final Map<String, String> resolvedVariables = null;
     final String regexpFilterText = null;
     final String regexpFilterExpression = null;
 
     final GenericTriggerResults sut =
         new GenericTriggerResults(
-            item, resolvedVariables, regexpFilterText, regexpFilterExpression);
+            url, id, triggered, resolvedVariables, regexpFilterText, regexpFilterExpression);
 
     assertThat(sut) //
         .isNotNull();
   }
 
   @Test
   public void testNullApi() {
-    final Item item = mock(Item.class);
-    when(item.getId()) //
-        .thenReturn(2L);
-    when(item.getApi()) //
-        .thenReturn(null);
+    final String url = null;
+    final long id = 2L;
+    final boolean triggered = false;
     final Map<String, String> resolvedVariables = null;
     final String regexpFilterText = null;
     final String regexpFilterExpression = null;
 
     final GenericTriggerResults sut =
         new GenericTriggerResults(
-            item, resolvedVariables, regexpFilterText, regexpFilterExpression);
+            url, id, triggered, resolvedVariables, regexpFilterText, regexpFilterExpression);
 
     assertThat(sut) //
         .isNotNull();

src/test/java/org/jenkinsci/plugins/gwt/GenericTriggerTest.java

@@ -0,0 +1,43 @@
+package org.jenkinsci.plugins.gwt;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.jenkinsci.plugins.gwt.GenericTrigger.HEADER_DRY_RUN;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Map;
+import java.util.TreeMap;
+import org.junit.jupiter.api.Test;
+
+class GenericTriggerTest {
+
+  @Test
+  void testDryRun() {
+    assertThat(GenericTrigger.isDryRun(null)).isFalse();
+
+    final Map<String, List<String>> headers = new TreeMap<String, List<String>>();
+    assertThat(GenericTrigger.isDryRun(headers)).isFalse();
+
+    headers.put("whatever", null);
+    assertThat(GenericTrigger.isDryRun(headers)).isFalse();
+
+    final List<String> headerValues = Arrays.asList("true");
+    headers.put("whatever", headerValues);
+    assertThat(GenericTrigger.isDryRun(headers)).isFalse();
+
+    headers.put(HEADER_DRY_RUN, null);
+    assertThat(GenericTrigger.isDryRun(headers)).isFalse();
+
+    List<String> dryRunHeaderValues = Arrays.asList("false");
+    headers.put(HEADER_DRY_RUN, dryRunHeaderValues);
+    assertThat(GenericTrigger.isDryRun(headers)).isFalse();
+
+    dryRunHeaderValues = Arrays.asList("x");
+    headers.put(HEADER_DRY_RUN, dryRunHeaderValues);
+    assertThat(GenericTrigger.isDryRun(headers)).isFalse();
+
+    dryRunHeaderValues = Arrays.asList("true");
+    headers.put(HEADER_DRY_RUN, dryRunHeaderValues);
+    assertThat(GenericTrigger.isDryRun(headers)).isTrue();
+  }
+}