fix(otel): disable recordNetworkBytesSaved for CSC

Author: PavelPashov

packages/client/lib/client/cache.ts

@@ -562,11 +562,8 @@ export class BasicClientSideCache extends ClientSideCacheProvider {
           CSC_RESULT.HIT,
           client._clientId,
         );
-        // Estimate bytes saved by avoiding network round-trip
-        // Note: JSON.stringify approximation; actual RESP wire size may differ (especially for Buffers)
-        const bytesEstimate = JSON.stringify(cacheEntry.value).length;
         OTelMetrics.instance.clientSideCacheMetrics.recordNetworkBytesSaved(
-          bytesEstimate,
+          cacheEntry.value,
           client._clientId,
         );
 

packages/client/lib/opentelemetry/metrics.spec.ts

@@ -1278,7 +1278,7 @@ describe("OTel Metrics E2E", function () {
       },
     );
 
-    testUtils.testAll(
+    testUtils.testWithClient(
       "should record redis.client.csc.network_saved",
       async (client) => {
         await client.ping();
@@ -1311,24 +1311,13 @@ describe("OTel Metrics E2E", function () {
         assert.strictEqual(attributes[OTEL_ATTRIBUTES.dbSystemName], "redis");
       },
       {
-        client: {
-          ...GLOBAL.SERVERS.OPEN,
-          clientOptions: {
-            RESP: 3,
-            clientSideCache: {
-              ttl: 1000,
-              maxEntries: 100,
-            },
-          },
-        },
-        cluster: {
-          ...GLOBAL.CLUSTERS.OPEN,
-          clusterConfiguration: {
-            RESP: 3,
-            clientSideCache: {
-              ttl: 1000,
-              maxEntries: 100,
-            },
+        ...GLOBAL.SERVERS.OPEN,
+        skipTest: true,
+        clientOptions: {
+          RESP: 3,
+          clientSideCache: {
+            ttl: 1000,
+            maxEntries: 100,
           },
         },
       },

packages/client/lib/opentelemetry/metrics.ts

@@ -338,14 +338,10 @@ class OTelClientSideCacheMetrics implements IOTelClientSideCacheMetrics {
     });
   }
 
-  public recordNetworkBytesSaved(bytes: number, clientId?: string) {
-    const clientAttributes = resolveClientAttributes(clientId);
-    this.#instruments.redisClientCscNetworkSaved.add(bytes, {
-      ...this.#options.attributes,
-      [OTEL_ATTRIBUTES.serverAddress]: clientAttributes?.host,
-      [OTEL_ATTRIBUTES.serverPort]: clientAttributes?.port?.toString(),
-      [OTEL_ATTRIBUTES.dbClientConnectionPoolName]: clientAttributes?.clientId,
-    });
+  public recordNetworkBytesSaved(value: unknown, clientId?: string) {
+    // TODO: `redis.client.csc.network_saved` cannot be computed correctly here
+    // because CSC stores transformed replies and does not retain raw byte size.
+    // Implement this at a lower protocol/parsing layer where response bytes are known.
   }
 }
 

packages/client/lib/opentelemetry/noop-metrics.ts

@@ -84,7 +84,7 @@ export class NoopClientSideCacheMetrics implements IOTelClientSideCacheMetrics {
   ) {}
 
   recordNetworkBytesSaved(
-    _bytes: number,
+    _value: unknown,
     _clientId?: string
   ) {}
 }

packages/client/lib/opentelemetry/types.ts

@@ -304,7 +304,7 @@ export interface IOTelClientSideCacheMetrics {
     count?: number,
     clientId?: string,
   ): void;
-  recordNetworkBytesSaved(bytes: number, clientId?: string): void;
+  recordNetworkBytesSaved(value: unknown, clientId?: string): void;
 }
 
 export interface IOTelPubSubMetrics {