feat(preview-service): add load and render duration calculation to preview service

packages/preview-service/src/jobProcessor.ts

@@ -82,11 +82,18 @@ const pageFunction = async ({
     logger.error({ err }, 'Page crashed')
     throw err
   })
+  const start = new Date().getTime()
   await page.goto(`http://127.0.0.1:${port}/index.html`)
   page.setDefaultTimeout(timeout)
   const previewResult = await page.evaluate(async (job: JobPayload) => {
+    const loadDone = new Date().getTime()
+    const loadDurationSeconds = loadDone - start
+    // measure here before load
     await window.load(job)
-    return await window.takeScreenshot()
+    const renderDurationSeconds = new Date().getTime() - loadDone
+    // measure here
+    const renderResult = await window.takeScreenshot()
+    return { ...renderResult, loadDurationSeconds, renderDurationSeconds }
   }, job)
 
   return { jobId: job.jobId, status: 'success', result: previewResult }

packages/shared/src/previews/interface.ts

@@ -1,13 +1,13 @@
-import { PreviewResult } from './job.js'
+import { PreviewPageResult } from './job.js'
 
 export interface PreviewGenerator {
   takeScreenshot: TakeScreenshot
   load: Load
 }
 
-export type TakeScreenshot = () => Promise<PreviewResult>
+export type TakeScreenshot = () => Promise<PreviewPageResult>
 
 export type LoadArgs = { url: string; token: string }
 export type Load = (args: LoadArgs) => Promise<void>
 
-export type { PreviewResult } from './job.js'
+export type { PreviewPageResult } from './job.js'

packages/shared/src/previews/job.ts

@@ -13,17 +13,27 @@ export const jobPayload = job.merge(
 )
 export type JobPayload = z.infer<typeof jobPayload>
 
-const previewResult = z.object({
+const previewPageResult = z.object({
   durationSeconds: z.number().describe('Duration to generate the preview, in seconds'),
   screenshots: z.record(z.string(), z.string())
 })
 
-export type PreviewResult = z.infer<typeof previewResult>
+const previewJobResult = previewPageResult.extend({
+  loadDurationSeconds: z
+    .number()
+    .describe('Duration to load the object from the server in seconds'),
+  renderDurationSeconds: z
+    .number()
+    .describe('Duration to render the preview images in seconds')
+})
+
+export type PreviewPageResult = z.infer<typeof previewPageResult>
+export type PreviewJobResult = z.infer<typeof previewJobResult>
 
 const previewSuccessPayload = job.merge(
   z.object({
     status: z.literal('success'),
-    result: previewResult
+    result: previewJobResult
   })
 )