scaffolder-backend: clarify type detection error message

.changeset/warm-moose-applaud.md

@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-scaffolder-backend': patch
+---
+
+Clearer error message when preparer or publisher type can't be determined.

plugins/scaffolder-backend/src/scaffolder/stages/prepare/preparers.ts

@@ -50,7 +50,17 @@ export class Preparers implements PreparerBuilder {
         if (detected) {
           return detected;
         }
-        throw new Error(`No preparer integration found for url "${location}"`);
+        if (type) {
+          throw new Error(
+            `No preparer configuration available for type '${type}' with url "${location}". ` +
+              "Make sure you've added appropriate configuration in the 'scaffolder' configuration section",
+          );
+        } else {
+          throw new Error(
+            `Failed to detect preparer type. Unable to determine integration type for location "${location}". ` +
+              "Please add appropriate configuration to the 'integrations' configuration section",
+          );
+        }
       }
       throw new Error(`No preparer registered for type: "${protocol}"`);
     }

plugins/scaffolder-backend/src/scaffolder/stages/publish/publishers.ts

@@ -51,7 +51,17 @@ export class Publishers implements PublisherBuilder {
         if (detected) {
           return detected;
         }
-        throw new Error(`No preparer integration found for url "${location}"`);
+        if (type) {
+          throw new Error(
+            `No publisher configuration available for type '${type}' with url "${location}". ` +
+              "Make sure you've added appropriate configuration in the 'scaffolder' configuration section",
+          );
+        } else {
+          throw new Error(
+            `Failed to detect publisher type. Unable to determine integration type for location "${location}". ` +
+              "Please add appropriate configuration to the 'integrations' configuration section",
+          );
+        }
       }
       throw new Error(`No publisher registered for type: "${protocol}"`);
     }