Add traces to track running arbitrary JS.

packages/backend-core/src/timers/timers.ts

@@ -30,7 +30,7 @@ export class ExecutionTimeTracker {
     return new ExecutionTimeTracker(limitMs)
   }
 
-  constructor(private limitMs: number) {}
+  constructor(readonly limitMs: number) {}
 
   private totalTimeMs = 0
 
@@ -46,6 +46,10 @@ export class ExecutionTimeTracker {
     }
   }
 
+  get elapsedMS() {
+    return this.totalTimeMs
+  }
+
   private checkLimit() {
     if (this.totalTimeMs > this.limitMs) {
       throw new ExecutionTimeoutError(

packages/server/src/jsRunner.ts

@@ -2,11 +2,13 @@ import vm from "vm"
 import env from "./environment"
 import { setJSRunner } from "@budibase/string-templates"
 import { context, timers } from "@budibase/backend-core"
+import tracer from "dd-trace"
 
 type TrackerFn = <T>(f: () => T) => T
 
 export function init() {
   setJSRunner((js: string, ctx: vm.Context) => {
+    return tracer.trace("runJS", {}, span => {
       const perRequestLimit = env.JS_PER_REQUEST_TIME_LIMIT_MS
       let track: TrackerFn = f => f()
       if (perRequestLimit) {
@@ -17,6 +19,12 @@ export function init() {
               timers.ExecutionTimeTracker.withLimit(perRequestLimit)
           }
           track = bbCtx.jsExecutionTracker.track.bind(bbCtx.jsExecutionTracker)
+          span?.addTags({
+            js: {
+              limitMS: bbCtx.jsExecutionTracker.limitMs,
+              elapsedMS: bbCtx.jsExecutionTracker.elapsedMS,
+            },
+          })
         }
       }
 
@@ -33,4 +41,5 @@ export function init() {
         })
       )
     })
+  })
 }