Add support for the custom attributes

README.md

@@ -213,7 +213,8 @@ The plugin decorates your Fastify instance with a `NewRelicTransactionManager`,
 
 - `start()`, which takes a `jobName`, and starts a background transaction with the provided name;
 - `stop()`, which takes a `jobId`, and ends the background transaction referenced by the ID;
-- `addCustomAttribute()`, which takes `attrName` and `attrValue` and records the custom attribute as such defined. `attrValue` can be a string, a number, or a boolean.
+- `addCustomAttribute()`, which takes `attrName` and `attrValue` and adds the custom attribute to the current transaction. `attrValue` can be a string, a number, or a boolean.
+- `addCustomAttributes()`, which passes `atts` map of the custom attributes to the current transaction. `_uniqueTransactionKey` argument is not used (because New Relic doesn't support setting custom attributes directly on the transaction handle), any string can be passed.
 
 ### Amplitude Plugin
 

lib/plugins/newrelicTransactionManagerPlugin.ts

@@ -14,6 +14,7 @@ interface Newrelic {
   shutdown: typeof Shutdown
   getTransaction: typeof GetTransaction
   addCustomAttribute(key: string, value: string | number | boolean): void
+  addCustomAttributes(atts: { [key: string]: string | number | boolean }): void
 }
 
 let newrelic: Newrelic
@@ -50,6 +51,17 @@ export class NewRelicTransactionManager implements TransactionObservabilityManag
     newrelic.addCustomAttribute(attrName, attrValue)
   }
 
+  public addCustomAttributes(
+    _uniqueTransactionKey: string,
+    atts: { [p: string]: string | number | boolean },
+  ): void {
+    if (!this.isEnabled) {
+      return
+    }
+
+    newrelic.addCustomAttributes(atts)
+  }
+
   /**
    * @param transactionName - used for grouping similar transactions together
    * @param uniqueTransactionKey - used for identifying specific ongoing transaction. Must be reasonably unique to reduce possibility of collisions

lib/plugins/prometheus/PrometheusCounterTransactionManager.ts

@@ -6,17 +6,25 @@ import type { Counter } from 'prom-client'
  * TransactionObservabilityManager implementation that uses Prometheus counter
  * to track the number of started, failed and success transactions.
  */
-export class PrometheusCounterTransactionManager implements TransactionObservabilityManager {
+export class PrometheusCounterTransactionManager<CustomLabels extends string = never>
+  implements TransactionObservabilityManager
+{
   private readonly metricName: string
   private readonly metricDescription: string
   private readonly counter?: Counter<'status' | 'transactionName'>
 
   private readonly transactionNameByKey: Map<string, string> = new Map()
+  private readonly customLabelsByKey: Map<string, Record<CustomLabels, string>> = new Map()
 
-  constructor(metricName: string, metricDescription: string, appMetrics?: IFastifyMetrics) {
+  constructor(
+    metricName: string,
+    metricDescription: string,
+    appMetrics?: IFastifyMetrics,
+    customLabels?: string[],
+  ) {
     this.metricName = metricName
     this.metricDescription = metricDescription
-    this.counter = this.registerMetric(appMetrics)
+    this.counter = this.registerMetric(appMetrics, customLabels)
   }
 
   start(transactionName: string, uniqueTransactionKey: string): void {
@@ -37,11 +45,38 @@ export class PrometheusCounterTransactionManager implements TransactionObservabi
     const transactionName = this.transactionNameByKey.get(uniqueTransactionKey)
     if (!transactionName) return
 
-    this.counter?.inc({ status: wasSuccessful ? 'success' : 'failed', transactionName })
+    const labels: Record<'status' | 'transactionName', string> = {
+      status: wasSuccessful ? 'success' : 'failed',
+      transactionName,
+    }
+    let labelsWithCustom: Record<'status' | 'transactionName' | CustomLabels, string> | undefined
+    if (this.customLabelsByKey.has(uniqueTransactionKey)) {
+      const customLabels = this.customLabelsByKey.get(uniqueTransactionKey)
+      labelsWithCustom = {
+        ...labels,
+        // biome-ignore lint/style/noNonNullAssertion: we already checked the presence
+        ...customLabels!,
+      }
+    }
+
+    this.counter?.inc(labelsWithCustom ?? labels)
     this.transactionNameByKey.delete(uniqueTransactionKey)
+    this.customLabelsByKey.delete(uniqueTransactionKey)
+  }
+
+  // Prometheus labels are the way Prometheus handles custom attributes
+  addCustomAttributes(
+    uniqueTransactionKey: string,
+    atts: { [p: string]: string | number | boolean },
+  ): void {
+    const transactionName = this.transactionNameByKey.get(uniqueTransactionKey)
+    if (!transactionName) return
+
+    // @ts-expect-error We only enforce types lightly here. If this ever causes us problem, we can start doing runtime validation here, but it seems to be an overkill for now.
+    this.customLabelsByKey.set(uniqueTransactionKey, atts)
   }
 
-  private registerMetric(appMetrics?: IFastifyMetrics) {
+  private registerMetric(appMetrics?: IFastifyMetrics, customLabels: string[] = []) {
     if (!appMetrics) return
 
     const existingMetric: Counter | undefined = appMetrics.client.register.getSingleMetric(
@@ -53,7 +88,7 @@ export class PrometheusCounterTransactionManager implements TransactionObservabi
     return new appMetrics.client.Counter({
       name: this.metricName,
       help: this.metricDescription,
-      labelNames: ['status', 'transactionName'],
+      labelNames: ['status', 'transactionName', ...customLabels],
     })
   }
 }

package.json

@@ -35,7 +35,7 @@
         "@amplitude/analytics-node": "^1.3.6",
         "@bugsnag/js": "^8.1.2",
         "@lokalise/error-utils": "^2.2.0",
-        "@splitsoftware/splitio": "^11.0.1",
+        "@splitsoftware/splitio": "^11.0.3",
         "@supercharge/promise-pool": "^3.2.0",
         "fastify-metrics": "^12.1.0",
         "fastify-plugin": "^5.0.1",
@@ -47,7 +47,7 @@
     "peerDependencies": {
         "@fastify/jwt": "^9.0.1",
         "@lokalise/background-jobs-common": ">=8.0.0",
-        "@lokalise/node-core": ">=12.0.0",
+        "@lokalise/node-core": ">=13.3.0",
         "bullmq": "^5.19.0",
         "fastify": "^5.0.0",
         "ioredis": "^5.4.1",
@@ -59,24 +59,24 @@
         "@amplitude/analytics-types": "^2.8.4",
         "@biomejs/biome": "^1.9.4",
         "@lokalise/backend-http-client": "^3.0.0",
-        "@lokalise/background-jobs-common": "^9.0.0",
+        "@lokalise/background-jobs-common": "^9.0.3",
         "@lokalise/biome-config": "^1.5.0",
-        "@lokalise/node-core": "^13.1.0",
-        "@types/newrelic": "^9.14.5",
-        "@types/node": "^22.9.0",
-        "@vitest/coverage-v8": "^2.1.4",
+        "@lokalise/node-core": "^13.3.0",
+        "@types/newrelic": "^9.14.6",
+        "@types/node": "^22.10.2",
+        "@vitest/coverage-v8": "^2.1.8",
         "auto-changelog": "^2.4.0",
-        "bullmq": "^5.21.1",
-        "fastify": "^5.1.0",
+        "bullmq": "^5.34.2",
+        "fastify": "^5.2.0",
         "fastify-type-provider-zod": "^4.0.2",
         "ioredis": "^5.4.1",
-        "newrelic": "12.8.1",
-        "pino": "^9.4.0",
+        "newrelic": "12.8.2",
+        "pino": "^9.5.0",
         "pino-pretty": "^13.0.0",
         "shx": "^0.3.4",
-        "typescript": "^5.6.3",
-        "vitest": "^2.1.4",
-        "zod": "^3.23.8"
+        "typescript": "^5.7.2",
+        "vitest": "^2.1.8",
+        "zod": "^3.24.1"
     },
     "engines": {
         "node": ">=20"