servicenow: truncate very long field values (elastic#11982)

It seems that some people store very long string values in servicenow
tables, resulting in failure to ingest. This change truncates those
fields to fit within the field length limit.

packages/servicenow/changelog.yml

@@ -1,4 +1,9 @@
 # newer versions go on top
+- version: "0.5.0"
+  changes:
+    - description: Truncate very long field values.
+      type: enhancement
+      link: https://github.com/elastic/integrations/pull/11982
 - version: "0.4.0"
   changes:
     - description: Replace dropdown with the textbox for the timezone offset parameter.

packages/servicenow/data_stream/event/elasticsearch/ingest_pipeline/default.yml

@@ -3285,6 +3285,28 @@ processors:
           return false;
         }
         drop(ctx);
+  - script:
+      tag: script_to_truncate_long_fields
+      lang: painless
+      description: Truncate fields that are over length.
+      source: |-
+        def filterMassive(def src) {
+          if (src instanceof Map) {
+            for (def entry: src.entrySet()) {
+              entry.setValue(filterMassive(entry.getValue()));
+            }
+            return src;
+          } else if (src instanceof List) {
+            for (int i = 0; i < src.length; i++) {
+              src[i] = filterMassive(src[i]);
+            }
+            return src;
+          } else if (src instanceof String && src.length() > 32766) {
+            return src.substring(0, 32700)+' (truncated)';
+          }
+          return src;
+        }
+        filterMassive(ctx);
   - set:
       field: event.kind
       tag: set_pipeline_error_into_event_kind

packages/servicenow/manifest.yml

@@ -1,7 +1,7 @@
 format_version: 3.2.1
 name: servicenow
 title: "ServiceNow"
-version: 0.4.0
+version: 0.5.0
 description: "Collect logs from ServiceNow with Elastic Agent."
 type: integration
 categories: