From 5c8d888e383c8343fba87808b776d15c3df182ce Mon Sep 17 00:00:00 2001
From: Carlos Crespo <crespocarlos@users.noreply.github.com>
Date: Wed, 27 Nov 2024 11:55:51 +0100
Subject: [PATCH] [APM] Make `trace.id` an optional field (#201821)

fixes [#201803](https://github.com/elastic/kibana/issues/201803)

## Summary

This PR fixes the error sample details function, making the `trace.id`
an optional field, to prevent the function from crashing in case this
field is not in the docs.

---------

Co-authored-by: Elastic Machine <elasticmachine@users.noreply.github.com>
(cherry picked from commit caea2066e4ca70e913b83a1ae13d3f2cd0d46804)

# Conflicts:
#	x-pack/test/api_integration/deployment_agnostic/apis/observability/apm/errors/group_id_samples.spec.ts
#	x-pack/test/apm_api_integration/tests/errors/generate_data.ts
---
 .../get_error_sample_details.ts               |  4 +--
 .../tests/errors/generate_data.ts             |  6 ++++-
 .../tests/errors/group_id_samples.spec.ts     | 27 +++++++++++++++++++
 3 files changed, 34 insertions(+), 3 deletions(-)

diff --git a/x-pack/plugins/observability_solution/apm/server/routes/errors/get_error_groups/get_error_sample_details.ts b/x-pack/plugins/observability_solution/apm/server/routes/errors/get_error_groups/get_error_sample_details.ts
index 91da19224d83c..954086ee53084 100644
--- a/x-pack/plugins/observability_solution/apm/server/routes/errors/get_error_groups/get_error_sample_details.ts
+++ b/x-pack/plugins/observability_solution/apm/server/routes/errors/get_error_groups/get_error_sample_details.ts
@@ -69,7 +69,6 @@ export async function getErrorSampleDetails({
   const requiredFields = asMutableArray([
     AGENT_NAME,
     PROCESSOR_EVENT,
-    TRACE_ID,
     TIMESTAMP_US,
     AT_TIMESTAMP,
     SERVICE_NAME,
@@ -78,6 +77,7 @@ export async function getErrorSampleDetails({
   ] as const);
 
   const optionalFields = asMutableArray([
+    TRACE_ID,
     TRANSACTION_ID,
     SPAN_ID,
     AGENT_VERSION,
@@ -131,7 +131,7 @@ export async function getErrorSampleDetails({
   const errorFromFields = unflattenKnownApmEventFields(hit.fields, requiredFields);
 
   const transactionId = errorFromFields.transaction?.id ?? errorFromFields.span?.id;
-  const traceId = errorFromFields.trace.id;
+  const traceId = errorFromFields.trace?.id;
 
   let transaction: Transaction | undefined;
   if (transactionId && traceId) {
diff --git a/x-pack/test/apm_api_integration/tests/errors/generate_data.ts b/x-pack/test/apm_api_integration/tests/errors/generate_data.ts
index a7e627a048e05..7844168f3c11b 100644
--- a/x-pack/test/apm_api_integration/tests/errors/generate_data.ts
+++ b/x-pack/test/apm_api_integration/tests/errors/generate_data.ts
@@ -4,7 +4,7 @@
  * 2.0; you may not use this file except in compliance with the Elastic License
  * 2.0.
  */
-import { apm, timerange } from '@kbn/apm-synthtrace-client';
+import { ApmFields, apm, timerange } from '@kbn/apm-synthtrace-client';
 import type { ApmSynthtraceEsClient } from '@kbn/apm-synthtrace';
 
 export const config = {
@@ -25,11 +25,13 @@ export async function generateData({
   serviceName,
   start,
   end,
+  overrides,
 }: {
   apmSynthtraceEsClient: ApmSynthtraceEsClient;
   serviceName: string;
   start: number;
   end: number;
+  overrides?: Partial<ApmFields>;
 }) {
   const serviceGoProdInstance = apm
     .service({ name: serviceName, environment: 'production', agentName: 'go' })
@@ -47,6 +49,7 @@ export async function generateData({
         .generator((timestamp) =>
           serviceGoProdInstance
             .transaction({ transactionName: transaction.name })
+            .overrides(overrides ? overrides : {})
             .timestamp(timestamp)
             .duration(1000)
             .success()
@@ -57,6 +60,7 @@ export async function generateData({
         .generator((timestamp) =>
           serviceGoProdInstance
             .transaction({ transactionName: transaction.name })
+            .overrides(overrides ? overrides : {})
             .errors(
               serviceGoProdInstance
                 .error({ message: `Error ${index}`, type: transaction.name })
diff --git a/x-pack/test/apm_api_integration/tests/errors/group_id_samples.spec.ts b/x-pack/test/apm_api_integration/tests/errors/group_id_samples.spec.ts
index ea74f1fa622d8..4b4f767daccbb 100644
--- a/x-pack/test/apm_api_integration/tests/errors/group_id_samples.spec.ts
+++ b/x-pack/test/apm_api_integration/tests/errors/group_id_samples.spec.ts
@@ -138,6 +138,33 @@ export default function ApiTest({ getService }: FtrProviderContext) {
       });
     });
 
+    describe('error sample without trace.id', () => {
+      before(async () => {
+        await generateData({
+          serviceName,
+          start,
+          end,
+          apmSynthtraceEsClient,
+          overrides: {
+            'trace.id': undefined,
+          },
+        });
+      });
+
+      after(() => apmSynthtraceEsClient.clean());
+
+      it('returns 200', async () => {
+        const errorsSamplesResponse = await callErrorGroupSamplesApi({
+          groupId: '0000000000000000000000000Error 1',
+        });
+
+        const errorId = errorsSamplesResponse.body.errorSampleIds[0];
+
+        const response = await callErrorSampleDetailsApi(errorId);
+        expect(response.status).to.be(200);
+      });
+    });
+
     describe('with sampled and unsampled transactions', () => {
       let errorGroupSamplesResponse: ErrorGroupSamples;