fix(scaffolder): properly set isDryRun flag in dry-run mode

Signed-off-by: Phil Kuang <pkuang@factset.com>

.changeset/spicy-lizards-pay.md

@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-scaffolder-backend': patch
+---
+
+Properly set `ctx.isDryRun` when running actions in dry run mode. Also always log action inputs for debugging purposes when running in dry run mode.

plugins/scaffolder-backend/src/scaffolder/tasks/NunjucksWorkflowRunner.test.ts

@@ -56,9 +56,11 @@ describe('DefaultWorkflowRunner', () => {
   const createMockTaskWithSpec = (
     spec: TaskSpec,
     secrets?: TaskSecrets,
+    isDryRun?: boolean,
   ): TaskContext => ({
     spec,
     secrets,
+    isDryRun,
     complete: async () => {},
     done: false,
     emitLog: async () => {},
@@ -85,6 +87,7 @@ describe('DefaultWorkflowRunner', () => {
     actionRegistry.register({
       id: 'jest-validated-action',
       description: 'Mock action for testing',
+      supportsDryRun: true,
       handler: fakeActionHandler,
       schema: {
         input: {
@@ -640,4 +643,32 @@ describe('DefaultWorkflowRunner', () => {
       });
     });
   });
+
+  describe('dry run', () => {
+    it('sets isDryRun flag correctly', async () => {
+      const task = createMockTaskWithSpec(
+        {
+          apiVersion: 'scaffolder.backstage.io/v1beta3',
+          parameters: {},
+          output: {},
+          steps: [
+            {
+              id: 'test',
+              name: 'name',
+              action: 'jest-validated-action',
+              input: { foo: 1 },
+            },
+          ],
+        },
+        {
+          backstageToken: 'secret',
+        },
+        true,
+      );
+
+      await runner.execute(task);
+
+      expect(fakeActionHandler.mock.calls[0][0].isDryRun).toEqual(true);
+    });
+  });
 });

plugins/scaffolder-backend/src/scaffolder/tasks/NunjucksWorkflowRunner.ts

@@ -236,25 +236,53 @@ export class NunjucksWorkflowRunner implements WorkflowRunner {
           const action = this.options.actionRegistry.get(step.action);
           const { taskLogger, streamLogger } = createStepLogger({ task, step });
 
-          if (task.isDryRun && !action.supportsDryRun) {
-            task.emitLog(
-              `Skipping because ${action.id} does not support dry-run`,
-              {
-                stepId: step.id,
-                status: 'skipped',
-              },
+          if (task.isDryRun) {
+            const redactedSecrets = Object.fromEntries(
+              Object.entries(task.secrets ?? {}).map(secret => [
+                secret[0],
+                '[REDACTED]',
+              ]),
             );
-            const outputSchema = action.schema?.output;
-            if (outputSchema) {
-              context.steps[step.id] = {
-                output: generateExampleOutput(outputSchema) as {
-                  [name in string]: JsonValue;
+            const debugInput =
+              (step.input &&
+                this.render(
+                  step.input,
+                  {
+                    ...context,
+                    secrets: redactedSecrets,
+                  },
+                  renderTemplate,
+                )) ??
+              {};
+            taskLogger.info(
+              `Running ${
+                action.id
+              } in dry-run mode with inputs (secrets redacted): ${JSON.stringify(
+                debugInput,
+                undefined,
+                2,
+              )}`,
+            );
+            if (!action.supportsDryRun) {
+              task.emitLog(
+                `Skipping because ${action.id} does not support dry-run`,
+                {
+                  stepId: step.id,
+                  status: 'skipped',
                 },
-              };
-            } else {
-              context.steps[step.id] = { output: {} };
+              );
+              const outputSchema = action.schema?.output;
+              if (outputSchema) {
+                context.steps[step.id] = {
+                  output: generateExampleOutput(outputSchema) as {
+                    [name in string]: JsonValue;
+                  },
+                };
+              } else {
+                context.steps[step.id] = { output: {} };
+              }
+              continue;
             }
-            continue;
           }
 
           // Secrets are only passed when templating the input to actions for security reasons
@@ -301,6 +329,7 @@ export class NunjucksWorkflowRunner implements WorkflowRunner {
             },
             templateInfo: task.spec.templateInfo,
             user: task.spec.user,
+            isDryRun: task.isDryRun,
           });
 
           // Remove all temporary directories that were created when executing the action