feat: add pipeline graph view node explain entrypoint

src/main/java/io/jenkins/plugins/explain_error/ConsoleExplainErrorAction.java

@@ -1,6 +1,5 @@
 package io.jenkins.plugins.explain_error;
 
-import com.google.common.annotations.VisibleForTesting;
 import hudson.model.Result;
 import hudson.model.Run;
 import jenkins.model.RunAction2;
@@ -86,17 +85,13 @@
             if (!forceNew && existingAction != null && existingAction.hasValidExplanation()) {
                 recordUsage(UsageEvent.Result.CACHE_HIT, existingAction.getProviderName(),
                         existingAction.getProviderModel(), startTimeNanos, existingAction.getInputLogLineCount());
-                // Return existing explanation with a flag indicating it's cached
-                writeJsonResponse(rsp, "success", existingAction.getProviderName(), createCachedResponse(existingAction.getExplanation()));
+                // Return existing explanation
+                writeJsonResponse(rsp, "success", existingAction.getProviderName(), existingAction.getExplanation());
                 return;
             }
 
             // Optionally allow maxLines as a parameter, default to 200
-            int maxLines = 200;
-            String maxLinesParam = req.getParameter("maxLines");
-            if (maxLinesParam != null) {
-                try { maxLines = Integer.parseInt(maxLinesParam); } catch (NumberFormatException ignore) {}
-            }
+            int maxLines = parseMaxLines(req, 200);
 
             // Fetch the last N lines of the log
             PipelineLogExtractor logExtractor = new PipelineLogExtractor(run, maxLines, Jenkins.getAuthentication2(),
@@ -120,6 +115,100 @@
         }
     }
 
+    /**
+     * AJAX endpoint to explain a selected Pipeline Graph View node.
+     */
+    @RequirePOST
+    public void doExplainNodeError(StaplerRequest2 req, StaplerResponse2 rsp) throws IOException {
+        long startTimeNanos = System.nanoTime();
+        String nodeId = req.getParameter("nodeId");
+        nodeId = nodeId != null ? nodeId.trim() : "";
+
+        try {
+            run.checkPermission(hudson.model.Item.READ);
+
+            if (nodeId.isEmpty()) {
+                recordUsage(UsageEvent.EntryPoint.PIPELINE_GRAPH_NODE, UsageEvent.Result.DISABLED,
+                        null, null, startTimeNanos, 0);
+                writeJsonResponse(rsp, "warning", "Unknown", "No Pipeline node was selected.");
+                return;
+            }
+
+            boolean forceNew = "true".equals(req.getParameter("forceNew"));
+            StepErrorExplanationAction stepAction = run.getAction(StepErrorExplanationAction.class);
+            StepErrorExplanationAction.Entry existing = stepAction != null ? stepAction.getExplanation(nodeId) : null;
+            if (!forceNew && existing != null && existing.hasValidExplanation()) {
+                this.urlString = existing.getUrlString();
+                recordUsage(UsageEvent.EntryPoint.PIPELINE_GRAPH_NODE, UsageEvent.Result.CACHE_HIT,
+                        existing.getProviderName(), existing.getProviderModel(), startTimeNanos,
+                        existing.getInputLogLineCount());
+                writeJsonResponse(rsp, "success", existing.getProviderName(), existing.getExplanation());
+                return;
+            }
+
+            int maxLines = parseMaxLines(req, 200);
+            PipelineLogExtractor logExtractor = new PipelineLogExtractor(run, maxLines, Jenkins.getAuthentication2(),
+                    false, null);
+            PipelineLogExtractor.ExtractionResult extractionResult = logExtractor.extractNodeLog(nodeId);
+            this.urlString = extractionResult.url();
+            if (extractionResult.logLines().isEmpty()) {
+                recordUsage(UsageEvent.EntryPoint.PIPELINE_GRAPH_NODE, UsageEvent.Result.DISABLED,
+                        null, null, startTimeNanos, 0);
+                writeJsonResponse(rsp, "warning", "Unknown",
+                        "No log output found for the selected Pipeline node.");
+                return;
+            }
+
+            String errorText = String.join("\n", extractionResult.logLines());
+            ErrorExplainer explainer = new ErrorExplainer();
+            try {
+                ErrorExplanationAction explanation = explainer.explainErrorText(errorText, urlString, run,
+                        UsageEvent.EntryPoint.PIPELINE_GRAPH_NODE, false);
+                StepErrorExplanationAction cacheAction = getOrCreateStepAction();
+                cacheAction.putExplanation(nodeId, explanation);
+                run.save();
+                writeJsonResponse(rsp, "success", explanation.getProviderName(), explanation.getExplanation());
+            } catch (ExplanationException ee) {
+                writeJsonResponse(rsp, ee.getLevel(), explainer.getProviderName(), ee.getMessage());
+            }
+        } catch (Exception e) {
+            LOGGER.severe("=== EXPLAIN PIPELINE NODE REQUEST FAILED ===");
+            LOGGER.severe("Error explaining pipeline node: " + e.getMessage());
+            writeJsonResponse(rsp, "error", "Unknown", "Error: " + e.getMessage());
+        }
+    }
+
+    /**
+     * AJAX endpoint to retrieve a previously generated explanation for a Pipeline node.
+     * Only returns cached results; never triggers AI generation.
+     */
+    @RequirePOST
+    public void doGetNodeExplanation(StaplerRequest2 req, StaplerResponse2 rsp) throws IOException {
+        String nodeId = req.getParameter("nodeId");
+        nodeId = nodeId != null ? nodeId.trim() : "";
+
+        try {
+            run.checkPermission(hudson.model.Item.READ);
+
+            if (nodeId.isEmpty()) {
+                writeJsonResponse(rsp, "warning", "Unknown", "No Pipeline node was selected.");
+                return;
+            }
+
+            StepErrorExplanationAction stepAction = run.getAction(StepErrorExplanationAction.class);
+            StepErrorExplanationAction.Entry entry = stepAction != null ? stepAction.getExplanation(nodeId) : null;
+            if (entry != null && entry.hasValidExplanation()) {
+                this.urlString = entry.getUrlString();
+                writeJsonResponse(rsp, "success", entry.getProviderName(), entry.getExplanation());
+            } else {
+                writeJsonResponse(rsp, "no_cache", "Unknown", "");
+            }
+        } catch (Exception e) {
+            LOGGER.warning("Error getting node explanation: " + e.getMessage());
+            writeJsonResponse(rsp, "error", "Unknown", "Error: " + e.getMessage());
+        }
+    }
+
     /**
      * AJAX endpoint to check build status.
      * Returns JSON with buildingStatus to determine if button should be shown. 0 - SUCCESS, 1 - RUNNING, 2 - FINISHED and FAILURE
@@ -129,15 +218,11 @@
         try {
             run.checkPermission(hudson.model.Item.READ);
 
-            Integer buildingStatus = run.isBuilding() ? 1 : 0;
-
-            if (buildingStatus == 0) {
-                Result result = run.getResult();
-                if (result == Result.SUCCESS) {
-                    buildingStatus = 0;
-                } else {
-                    buildingStatus = 2;
-                }
+            int buildingStatus = 0;
+            if (run.isBuilding()) {
+                buildingStatus = 1;
+            } else if (run.getResult() == Result.FAILURE) {
+                buildingStatus = 2;
             }
 
             rsp.setContentType("application/json");
@@ -167,30 +252,49 @@
         writer.flush();
     }
 
-    /**
-     * Create a response indicating this is a cached result.
-     * @param explanation The cached explanation
-     * @return The response string with cached indicator
-     */
-    @VisibleForTesting
-    String createCachedResponse(String explanation) {
-        return explanation + "\n\n[Note: This is a previously generated explanation. Use the 'Generate New' option to create a new one.]";
-    }
-
     public Run<?, ?> getRun() {
         return run;
     }
 
     private void recordUsage(UsageEvent.Result result, String providerName, String model,
                              long startTimeNanos, int inputLogLineCount) {
+        recordUsage(UsageEvent.EntryPoint.CONSOLE_ACTION, result, providerName, model,
+                startTimeNanos, inputLogLineCount);
+    }
+
+    private void recordUsage(UsageEvent.EntryPoint entryPoint, UsageEvent.Result result, String providerName,
+                             String model, long startTimeNanos, int inputLogLineCount) {
         UsageRecorders.get().record(new UsageEvent(
                 System.currentTimeMillis(),
-                UsageEvent.EntryPoint.CONSOLE_ACTION,
+                entryPoint,
                 result,
                 providerName,
                 model,
                 Math.max(0L, (System.nanoTime() - startTimeNanos) / 1_000_000L),
                 inputLogLineCount,
                 false));
     }
+
+    private StepErrorExplanationAction getOrCreateStepAction() {
+        StepErrorExplanationAction action = run.getAction(StepErrorExplanationAction.class);
+        if (action != null) {
+            return action;
+        }
+        action = new StepErrorExplanationAction();
+        run.addAction(action);
+        return action;
+    }
+
+    private int parseMaxLines(StaplerRequest2 req, int defaultValue) {
+        String maxLinesParam = req.getParameter("maxLines");
+        if (maxLinesParam == null) {
+            return defaultValue;
+        }
+        try {
+            int value = Integer.parseInt(maxLinesParam);
+            return value > 0 ? value : defaultValue;
+        } catch (NumberFormatException ignore) {
+            return defaultValue;
+        }
+    }
 }

src/main/java/io/jenkins/plugins/explain_error/ConsolePageDecorator.java

@@ -3,6 +3,7 @@
 import hudson.Extension;
 import hudson.model.PageDecorator;
 import hudson.model.Run;
+import jenkins.model.Jenkins;
 import org.kohsuke.stapler.Ancestor;
 import org.kohsuke.stapler.Stapler;
 
@@ -39,13 +40,26 @@
     }
 
     /**
-     * Helper method used by jelly to checked if we're on a console url.
+     * Helper method used by jelly to check if we're on a supported build page.
      */
     public boolean isPluginActive() {
+        return isConsolePage() || isPipelineGraphViewPage();
+    }
+
+    public boolean isConsolePage() {
         String uri = Stapler.getCurrentRequest2().getRequestURI();
         return uri.matches(".*/console(Full)?$");
     }
 
+    public boolean isPipelineGraphViewPage() {
+        String uri = Stapler.getCurrentRequest2().getRequestURI();
+        return isPipelineGraphViewUri(uri) && Jenkins.get().getPlugin("pipeline-graph-view") != null;
+    }
+
+    static boolean isPipelineGraphViewUri(String uri) {
+        return uri != null && uri.matches(".*/(stages|pipeline-overview)/?$");
+    }
+
     public String getRunUrl() {
         Ancestor ancestor = Stapler.getCurrentRequest2().findAncestor(Run.class);
         if (ancestor != null && ancestor.getObject() instanceof Run<?, ?> run) {
@@ -55,7 +69,15 @@
         }
     }
 
+    /**
+     * Returns the console-level explanation for pre-populating the Jelly view.
+     * Only relevant on console pages; returns null on graph view pages because
+     * graph view uses per-node {@link StepErrorExplanationAction} explanations.
+     */
     public ErrorExplanationAction getExistingExplanation() {
+        if (isPipelineGraphViewPage()) {
+            return null;
+        }
         Ancestor ancestor = Stapler.getCurrentRequest2().findAncestor(Run.class);
         if (ancestor != null && ancestor.getObject() instanceof Run<?, ?> run) {
             return run.getAction(ErrorExplanationAction.class);

src/main/java/io/jenkins/plugins/explain_error/ErrorExplainer.java

@@ -248,6 +248,12 @@ public ErrorExplanationAction explainErrorText(String errorText, String url, @No
     ErrorExplanationAction explainErrorText(String errorText, String url, @NonNull Run<?, ?> run,
                                             UsageEvent.EntryPoint entryPoint)
             throws IOException, ExplanationException {
+        return explainErrorText(errorText, url, run, entryPoint, true);
+    }
+
+    ErrorExplanationAction explainErrorText(String errorText, String url, @NonNull Run<?, ?> run,
+                                            UsageEvent.EntryPoint entryPoint, boolean storeBuildAction)
+            throws IOException, ExplanationException {
         String jobInfo ="[" + run.getParent().getFullName() + " #" + run.getNumber() + "]";
         long startTimeNanos = System.nanoTime();
         int inputLogLineCount = countLines(errorText);
@@ -289,8 +295,10 @@ ErrorExplanationAction explainErrorText(String errorText, String url, @NonNull R
             LOGGER.fine("Explanation length: " + explanation.length());
             ErrorExplanationAction action = new ErrorExplanationAction(explanation, url, errorText,
                     provider.getProviderName(), provider.getModel(), inputLogLineCount);
-            run.addOrReplaceAction(action);
-            run.save();
+            if (storeBuildAction) {
+                run.addOrReplaceAction(action);
+                run.save();
+            }
             recordUsage(entryPoint, UsageEvent.Result.SUCCESS, provider, startTimeNanos, inputLogLineCount, false);
 
             return action;