From 263c534429b1798fe456e02fac09aa2ba2df36f4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Alejandro=20Fern=C3=A1ndez=20Haro?=
 <alejandro.haro@elastic.co>
Date: Thu, 10 Aug 2023 17:27:30 +0200
Subject: [PATCH] [Telemetry Schema Validation] Allow `null` on `string`
 (#163499)

---
 .../src/schema_ftr_validations/schema_to_config_schema.ts      | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/packages/kbn-telemetry-tools/src/schema_ftr_validations/schema_to_config_schema.ts b/packages/kbn-telemetry-tools/src/schema_ftr_validations/schema_to_config_schema.ts
index b80a42e101284..5c12c199bbe6d 100644
--- a/packages/kbn-telemetry-tools/src/schema_ftr_validations/schema_to_config_schema.ts
+++ b/packages/kbn-telemetry-tools/src/schema_ftr_validations/schema_to_config_schema.ts
@@ -59,7 +59,8 @@ function valueSchemaToConfigSchema(value: TelemetrySchemaValue): Type<unknown> {
       case 'keyword':
       case 'text':
       case 'date':
-        return schema.string();
+        // Some plugins return `null` when there is no value to report
+        return schema.oneOf([schema.string(), schema.literal(null)]);
       case 'byte':
       case 'double':
       case 'float':