Fix hostname resolution in recent Jenkins versions

src/main/java/org/datadog/jenkins/plugins/datadog/traces/DatadogBaseBuildLogic.java

@@ -70,7 +70,7 @@ protected Set<String> getNodeLabels(Run<?,?> run, final String nodeName) {
 
             // If there is no labels and the node name is master,
             // we force the label "master".
-            if("master".equalsIgnoreCase(nodeName)){
+            if("master".equalsIgnoreCase(nodeName) || "built-in".equalsIgnoreCase(nodeName)) {
                 final Set<String> masterLabels = new HashSet<>();
                 masterLabels.add("master");
                 return masterLabels;

src/main/java/org/datadog/jenkins/plugins/datadog/traces/DatadogBasePipelineLogic.java

@@ -238,7 +238,7 @@ protected Set<String> getNodeLabels(Run run, BuildPipelineNode current, String n
 
         // If there is no labels and the node name is master,
         // we force the label "master".
-        if ("master".equalsIgnoreCase(nodeName)) {
+        if ("master".equalsIgnoreCase(nodeName) || "built-in".equalsIgnoreCase(nodeName)) {
             final Set<String> masterLabels = new HashSet<>();
             masterLabels.add("master");
             return masterLabels;

src/main/java/org/datadog/jenkins/plugins/datadog/traces/DatadogTraceBuildLogic.java

@@ -140,7 +140,7 @@ public void finishBuildTrace(final BuildData buildData, final Run<?,?> run) {
         }
 
         // If the NodeName == "master", we don't set _dd.hostname. It will be overridden by the Datadog Agent. (Traces are only available using Datadog Agent)
-        if(!"master".equalsIgnoreCase(nodeName)){
+        if(!"master".equalsIgnoreCase(nodeName) && !"built-in".equalsIgnoreCase(nodeName)) {
             final String workerHostname = getNodeHostname(run, updatedBuildData);
             // If the worker hostname is equals to controller hostname but the node name is not "master"
             // then we could not detect the worker hostname properly. We set _dd.hostname to 'none' explicitly.

src/main/java/org/datadog/jenkins/plugins/datadog/traces/DatadogTracePipelineLogic.java

@@ -246,7 +246,7 @@ private Map<String, Object> buildTraceTags(final Run run, final BuildPipelineNod
         }
 
         // If the NodeName == "master", we don't set _dd.hostname. It will be overridden by the Datadog Agent. (Traces are only available using Datadog Agent)
-        if(!"master".equalsIgnoreCase(nodeName)){
+        if(!"master".equalsIgnoreCase(nodeName) && !"built-in".equalsIgnoreCase(nodeName)) {
             final String workerHostname = getNodeHostname(run, current);
             // If the worker hostname is equals to controller hostname but the node name is not "master"
             // then we could not detect the worker hostname properly. We set _dd.hostname to 'none' explicitly.

src/main/java/org/datadog/jenkins/plugins/datadog/traces/DatadogWebhookBuildLogic.java

@@ -194,8 +194,8 @@ public void finishBuildTrace(final BuildData buildData, final Run<?,?> run) {
 
             final String nodeName = getNodeName(run, buildData, updatedBuildData);
             nodePayload.put("name", nodeName);
+            if(!"master".equalsIgnoreCase(nodeName) && !"built-in".equalsIgnoreCase(nodeName)) {
 
-            if(!"master".equalsIgnoreCase(nodeName)){
                 final String workerHostname = getNodeHostname(run, updatedBuildData);
                 // If the worker hostname is equals to controller hostname but the node name is not "master"
                 // then we could not detect the worker hostname properly. We set _dd.hostname to 'none' explicitly.

src/main/java/org/datadog/jenkins/plugins/datadog/traces/DatadogWebhookPipelineLogic.java

@@ -153,7 +153,7 @@ private void collectTraces(final Run run, final BuildData buildData, final Build
             final String nodeName = getNodeName(run, current, buildData);
             nodePayload.put("name", nodeName);
 
-            if(!"master".equalsIgnoreCase(nodeName)){
+            if(!"master".equalsIgnoreCase(nodeName) && !"built-in".equalsIgnoreCase(nodeName)) {
                 final String workerHostname = getNodeHostname(run, current);
                 // If the worker hostname is equals to controller hostname but the node name is not "master"
                 // then we could not detect the worker hostname properly. We set _dd.hostname to 'none' explicitly.

src/main/java/org/datadog/jenkins/plugins/datadog/util/git/GitUtils.java

@@ -59,7 +59,7 @@ public static FilePath buildFilePath(final String nodeName, final String workspa
         }
 
         try {
-            return "master".equals(nodeName) ? new FilePath(FilePath.localChannel, workspace):  FilePathUtils.find(nodeName, workspace);
+            return ("master".equals(nodeName) || "built-in".equals(nodeName)) ? new FilePath(FilePath.localChannel, workspace):  FilePathUtils.find(nodeName, workspace);
         } catch (Exception e) {
             LOGGER.fine("Unable to build FilePath. Error: " + e);
             return null;

src/main/resources/org/datadog/jenkins/plugins/datadog/DatadogGlobalConfiguration/help-hostnameEntry.html

@@ -1,3 +1,3 @@
 <div>
-    Enter the name you'd like to identify your Jenkins host as. Must comply with the hostname format set in <a target="_blank" href="https://tools.ietf.org/html/rfc1123#section-2">RFC 1123</a>.
+    Enter the name you'd like to identify your Jenkins host as. Must comply with the hostname format set in <a target="_blank" href="https://tools.ietf.org/html/rfc1123#section-2">RFC 1123</a>. Leave empty to use the detected hostname.
 </div>