feat: Added partial granularity tracking metrics

lib/metrics/names.js

@@ -291,11 +291,15 @@ const DISTRIBUTED_TRACE = {
 
 const SPAN_EVENT_PREFIX = 'SpanEvent/'
 
+const PARTIAL_GRANULARITY = 'PartialGranularity/'
+
 const SPAN_EVENTS = {
   SEEN: SUPPORTABILITY.PREFIX + SPAN_EVENT_PREFIX + 'TotalEventsSeen',
   SENT: SUPPORTABILITY.PREFIX + SPAN_EVENT_PREFIX + 'TotalEventsSent',
   DROPPED: SUPPORTABILITY.PREFIX + SPAN_EVENT_PREFIX + 'Discarded',
-  LIMIT: SUPPORTABILITY.PREFIX + SPAN_EVENT_PREFIX + 'Limit'
+  LIMIT: SUPPORTABILITY.PREFIX + SPAN_EVENT_PREFIX + 'Limit',
+  KEPT: SUPPORTABILITY.PREFIX + 'DistributedTrace/' + PARTIAL_GRANULARITY + '%s' + '/Span/Kept',
+  INSTRUMENTED: SUPPORTABILITY.PREFIX + 'DistributedTrace/' + PARTIAL_GRANULARITY + '%s' + '/Span/Instrumented',
 }
 
 const INFINITE_TRACING = {

lib/spans/span-event-aggregator.js

@@ -9,6 +9,7 @@ const logger = require('../logger').child({ component: 'span_aggregator' })
 const EventAggregator = require('../aggregators/event-aggregator')
 const SpanEvent = require('./span-event')
 const NAMES = require('../metrics/names')
+const util = require('util')
 
 const DEFAULT_SPAN_EVENT_LIMIT = 2000
 // Used only when server value missing
@@ -75,10 +76,18 @@ class SpanEventAggregator extends EventAggregator {
 
       return false
     }
+
+    if (transaction.partialType) {
+      this._metrics.getOrCreateMetric(util.format(this._metricNames.INSTRUMENTED, transaction.partialType)).incrementCallCount()
+    }
+
     const span = SpanEvent.fromSegment({ segment, transaction, parentId, isRoot, inProcessSpans: this.inProcessSpans })
 
     if (span) {
       this.add(span, transaction.priority)
+      if (transaction.partialType) {
+        this._metrics.getOrCreateMetric(util.format(this._metricNames.KEPT, transaction.partialType)).incrementCallCount()
+      }
     }
 
     if (segment.spanLinks.length > 0) {

test/unit/spans/full-granularity-spans.test.js

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2025 New Relic Corporation. All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+'use strict'
+const assert = require('node:assert')
+const test = require('node:test')
+const helper = require('#testlib/agent_helper.js')
+const SpanEvent = require('#agentlib/spans/span-event.js')
+
+test('Partial Granularity metrics with Full Granularity settings', async (t) => {
+  t.beforeEach((ctx) => {
+    const agent = helper.loadMockedAgent({
+      distributed_tracing: {
+        enabled: true,
+        sampler: {
+          full_granularity: {
+            enabled: true
+          },
+          partial_granularity: {
+            enabled: false,
+          }
+        }
+      }
+    })
+    ctx.nr = { agent }
+  })
+
+  t.afterEach((ctx) => {
+    helper.unloadAgent(ctx.nr.agent)
+  })
+
+  await t.test('should not record partial granularity metrics when not part of partialTrace', (t, end) => {
+    const { agent } = t.nr
+    helper.runInTransaction(agent, (transaction) => {
+      const segment = transaction.trace.add('Datastore/operation/Redis/SET')
+      const span = SpanEvent.fromSegment({ segment, transaction, inProcessSpans: true })
+      assert.ok(span)
+      transaction.end()
+      const unscopedMetrics = agent.metrics._metrics.unscoped
+      assert.equal(unscopedMetrics['Supportability/DistributedTrace/PartialGranularity/reduced/Span/Instrumented'], undefined)
+      assert.equal(unscopedMetrics['Supportability/DistributedTrace/PartialGranularity/reduced/Span/Kept'], undefined)
+      assert.equal(unscopedMetrics['Supportability/DistributedTrace/PartialGranularity/essential/Span/Instrumented'], undefined)
+      assert.equal(unscopedMetrics['Supportability/DistributedTrace/PartialGranularity/essential/Span/Kept'], undefined)
+      end()
+    })
+  })
+})

test/unit/spans/partial-granularity-spans.test.js

@@ -16,12 +16,14 @@ for (const mode of MODES) {
       const agent = helper.loadMockedAgent({
         distributed_tracing: {
           enabled: true,
-          full_granularity: {
-            enabled: false
-          },
-          partial_granularity: {
-            enabled: true,
-            type: mode
+          sampler: {
+            full_granularity: {
+              enabled: false
+            },
+            partial_granularity: {
+              enabled: true,
+              type: mode
+            }
           }
         }
       })
@@ -172,5 +174,60 @@ for (const mode of MODES) {
         end()
       })
     })
+
+    await t.test('should record a instrumented and kept metric for exit span that has entity relationship attrs', (t, end) => {
+      const { agent } = t.nr
+      helper.runInTransaction(agent, (transaction) => {
+        transaction.partialType = mode
+        const segment = transaction.trace.add('Datastore/operation/Redis/SET')
+        segment.addAttribute('host', 'redis-service')
+        segment.addAttribute('port_path_or_id', 6379)
+        segment.addAttribute('foo', 'bar')
+        const spanContext = segment.getSpanContext()
+        spanContext.addCustomAttribute('custom', 'test')
+        const span = SpanEvent.fromSegment({ segment, transaction, inProcessSpans: true })
+        assert.ok(span)
+        transaction.end()
+
+        const unscopedMetrics = agent.metrics._metrics.unscoped
+        assert.equal(unscopedMetrics[`Supportability/DistributedTrace/PartialGranularity/${mode}/Span/Instrumented`].callCount, 1)
+        assert.equal(unscopedMetrics[`Supportability/DistributedTrace/PartialGranularity/${mode}/Span/Kept`].callCount, 1)
+        end()
+      })
+    })
+
+    await t.test('should record instrumented metric only for dropped exit span that does not have entity relationship attrs', (t, end) => {
+      const { agent } = t.nr
+      helper.runInTransaction(agent, (transaction) => {
+        transaction.partialType = mode
+        const segment = transaction.trace.add('Datastore/operation/Redis/SET')
+        segment.addAttribute('foo', 'bar')
+        const span = SpanEvent.fromSegment({ segment, transaction, inProcessSpans: true })
+        assert.ok(!span)
+        transaction.end()
+        const unscopedMetrics = agent.metrics._metrics.unscoped
+        assert.equal(unscopedMetrics[`Supportability/DistributedTrace/PartialGranularity/${mode}/Span/Instrumented`].callCount, 1)
+        // span was dropped so kept metric was not recorded
+        assert.equal(unscopedMetrics[`Supportability/DistributedTrace/PartialGranularity/${mode}/Span/Kept`], undefined)
+        end()
+      })
+    })
+
+    await t.test('should record instrumented metric only for dropped in process span', (t, end) => {
+      const { agent } = t.nr
+      helper.runInTransaction(agent, (transaction) => {
+        transaction.partialType = mode
+        const segment = transaction.trace.add('test-segment')
+        segment.addAttribute('foo', 'bar')
+        const span = SpanEvent.fromSegment({ segment, transaction, inProcessSpans: true })
+        assert.ok(!span)
+        transaction.end()
+        const unscopedMetrics = agent.metrics._metrics.unscoped
+        assert.equal(unscopedMetrics[`Supportability/DistributedTrace/PartialGranularity/${mode}/Span/Instrumented`].callCount, 1)
+        // span was dropped so kept metric was not recorded
+        assert.equal(unscopedMetrics[`Supportability/DistributedTrace/PartialGranularity/${mode}/Span/Kept`], undefined)
+        end()
+      })
+    })
   })
 }