Limit the length of errors that get written to the database

Signed-off-by: Gudmundur Orn Johannsson <gudmundur.orn@gmail.com>

.changeset/spotty-points-build.md

@@ -0,0 +1,6 @@
+---
+'@backstage/errors': patch
+'@backstage/plugin-catalog-backend': patch
+---
+
+Limit the length of error messages that get written to the database and logs - to prevent performance issues

plugins/catalog-backend/src/modules/core/UrlReaderProcessor.ts

@@ -97,7 +97,10 @@ export class UrlReaderProcessor implements CatalogProcessor {
       emit(processingResult.refresh(`${location.type}:${location.target}`));
     } catch (error) {
       assertError(error);
-      const message = `Unable to read ${location.type}, ${error}`;
+      const message = `Unable to read ${location.type}, ${error}`.substring(
+        0,
+        5000,
+      );
       if (error.name === 'NotModifiedError' && cacheItem) {
         for (const parseResult of cacheItem.value) {
           emit(parseResult);