dash: show size of return value in logs (#41063)

GitOrigin-RevId: 74239f6a449b16f472fa7bf700ea8d8297fce053

Author: Nicolapps

crates/local_backend/src/logs.rs

@@ -59,6 +59,7 @@ pub enum FunctionExecutionJson {
         request_id: String,
         execution_id: String,
         usage_stats: JsonValue,
+        return_bytes: Option<f64>,
         occ_info: Option<JsonValue>,
         execution_timestamp: f64,
         identity_type: String,
@@ -300,6 +301,7 @@ fn execution_to_json(
                     .map(|id| id.to_string()),
                 execution_id: execution.context.execution_id.to_string(),
                 usage_stats: usage_stats_json,
+                return_bytes: execution.return_bytes.map(|bytes| bytes as f64),
                 occ_info: occ_info_json,
                 execution_timestamp,
                 identity_type,
@@ -332,6 +334,7 @@ fn execution_to_json(
                 request_id: execution.context.request_id.to_string(),
                 execution_id: execution.context.execution_id.to_string(),
                 usage_stats: usage_stats_json,
+                return_bytes: None, // Not supported in HTTP actions
                 occ_info: occ_info_json,
                 execution_timestamp,
                 identity_type,

npm-packages/dashboard-common/src/features/logs/components/LogListResources.tsx

@@ -6,12 +6,15 @@ import {
   ChevronDownIcon,
   ChevronUpIcon,
   PieChartIcon,
+  QuestionMarkCircledIcon,
 } from "@radix-ui/react-icons";
+import { Tooltip } from "@ui/Tooltip";
 import { UsageStats } from "system-udfs/convex/_system/frontend/common";
 
 type RequestUsageStats = UsageStats & {
   actionsRuntimeMs: number;
   actionComputeMbMs: number;
+  returnBytes?: number;
 };
 
 export function LogListResources({ logs }: { logs: UdfLog[] }) {
@@ -39,6 +42,9 @@ export function LogListResources({ logs }: { logs: UdfLog[] }) {
           ret[key] += value ?? 0;
         }
       }
+      if ("returnBytes" in log && log.returnBytes) {
+        ret.returnBytes = (ret.returnBytes ?? 0) + log.returnBytes;
+      }
       if (
         log.kind === "outcome" &&
         (log.udfType === "Action" || log.udfType === "HttpAction")
@@ -129,6 +135,20 @@ export function LogListResources({ logs }: { logs: UdfLog[] }) {
                   written
                 </span>
               </li>
+              {usageStats.returnBytes && (
+                <li className="flex items-center justify-between py-2">
+                  <span className="flex items-center gap-1 text-center text-content-secondary">
+                    Return Value Size
+                    <Tooltip tip="Bandwidth from sending the return value of a function call to the user does not incur costs.">
+                      <QuestionMarkCircledIcon />
+                    </Tooltip>
+                  </span>
+                  <span className="text-content-primary">
+                    <strong>{formatBytes(usageStats.returnBytes)}</strong>{" "}
+                    returned
+                  </span>
+                </li>
+              )}
             </ul>
             {logs.filter((log) => log.kind === "outcome").length > 1 && (
               <div className="mt-3 text-content-secondary">

npm-packages/dashboard-common/src/lib/useLogs.ts

@@ -61,6 +61,7 @@ export type UdfLogOutcome = {
   kind: "outcome";
   error?: string;
   usageStats?: UsageStats;
+  returnBytes?: number;
   caller: string;
   environment: string;
   identityType: string;
@@ -178,6 +179,7 @@ export function processLogs(rawLogs: FunctionExecution[]): UdfLog[] {
         cachedResult: entry.cachedResult,
         kind: "outcome",
         usageStats: entry.usageStats,
+        returnBytes: entry.returnBytes,
         caller: entry.caller,
         environment: entry.environment,
         identityType: entry.identityType,

npm-packages/system-udfs/convex/_system/frontend/common.ts

@@ -63,6 +63,7 @@ export type FunctionExecutionCompletion = {
   requestId: string;
   executionId: string;
   usageStats?: UsageStats;
+  returnBytes?: number;
   caller: string;
   environment: string;
   identityType: string;