From 8bb568da2ac25d59d4878d86ea72a69057ed6c47 Mon Sep 17 00:00:00 2001
From: Jayc <mjayachand@gmail.com>
Date: Fri, 15 Mar 2024 15:16:19 +0530
Subject: [PATCH] chore: add request size metric

---
 src/controllers/userTransform.ts |  3 ++-
 src/services/userTransform.ts    | 17 +++++++----------
 src/util/prometheus.js           |  4 ++--
 3 files changed, 11 insertions(+), 13 deletions(-)

diff --git a/src/controllers/userTransform.ts b/src/controllers/userTransform.ts
index c344bd072a..3e01686a52 100644
--- a/src/controllers/userTransform.ts
+++ b/src/controllers/userTransform.ts
@@ -15,9 +15,10 @@ export class UserTransformController {
       '(User transform - router:/customTransform ):: Request to transformer',
       JSON.stringify(ctx.request.body),
     );
+    const requestSize = Number(ctx.request.get('content-length'));
     const events = ctx.request.body as ProcessorTransformationRequest[];
     const processedRespone: UserTransformationServiceResponse =
-      await UserTransformService.transformRoutine(events, ctx.state.features);
+      await UserTransformService.transformRoutine(events, ctx.state.features, requestSize);
     ctx.body = processedRespone.transformedEvents;
     ControllerUtility.postProcess(ctx, processedRespone.retryStatus);
     logger.debug(
diff --git a/src/services/userTransform.ts b/src/services/userTransform.ts
index 71a0c63e97..18c47ddc83 100644
--- a/src/services/userTransform.ts
+++ b/src/services/userTransform.ts
@@ -28,6 +28,7 @@ export class UserTransformService {
   public static async transformRoutine(
     events: ProcessorTransformationRequest[],
     features: FeatureFlags = {},
+    requestSize = 0,
   ): Promise<UserTransformationServiceResponse> {
     let retryStatus = 200;
     const groupedEvents: NonNullable<unknown> = groupBy(
@@ -162,24 +163,20 @@ export class UserTransformService {
             ),
           );
           stats.counter('user_transform_errors', eventsToProcess.length, {
-            ...getTransformationMetadata(eventsToProcess[0]?.metadata),
             status,
             ...metaTags,
+            ...getTransformationMetadata(eventsToProcess[0]?.metadata),
           });
         } finally {
           stats.timing('user_transform_request_latency', userFuncStartTime, {
-            ...getTransformationMetadata(eventsToProcess[0]?.metadata),
             ...metaTags,
+            ...getTransformationMetadata(eventsToProcess[0]?.metadata),
           });
 
-          stats.histogram(
-            'user_transform_request_size',
-            Buffer.byteLength(JSON.stringify(eventsToProcess)),
-            {
-              ...getTransformationMetadata(eventsToProcess[0]?.metadata),
-              ...metaTags,
-            },
-          );
+          stats.histogram('user_transform_batch_size', requestSize, {
+            ...metaTags,
+            ...getTransformationMetadata(eventsToProcess[0]?.metadata),
+          });
         }
 
         stats.counter('user_transform_requests', 1, {});
diff --git a/src/util/prometheus.js b/src/util/prometheus.js
index 9c26347208..5de7ac899d 100644
--- a/src/util/prometheus.js
+++ b/src/util/prometheus.js
@@ -675,8 +675,8 @@ class Prometheus {
         ],
       },
       {
-        name: 'user_transform_request_size',
-        help: 'user_transform_request_size',
+        name: 'user_transform_batch_size',
+        help: 'user_transform_batch_size',
         type: 'histogram',
         labelNames: [
           'workspaceId',