Files
hyperframes/packages/producer
Vance Ingalls cc9403b6bd test(producer): extract frameDirMaxIndexCache to its own module and pin cross-job isolation (#381)
## Summary

Extract the `frameDirMaxIndexCache` from a private module-scoped Map inside `renderOrchestrator.ts` into its own `frameDirCache.ts` module, then add a 11-test bun:test suite that pins the cross-job isolation contract added in Chunk 5B.

## Why

`Chunk 9E` of `plans/hdr-followups.md`. The cache lived as a private Map inside `renderOrchestrator.ts`, which made the cross-job isolation contract from Chunk 5B impossible to unit-test directly. Extracting it both makes the contract testable and reduces orchestrator complexity slightly.

## What changed

- New `packages/producer/src/services/frameDirCache.ts` exposes `getMaxFrameIndex` / `clearMaxFrameIndex` / `getMaxFrameIndexCacheSize` (plus a test-only `__resetMaxFrameIndexCacheForTests` helper). Behavior is unchanged: callers still get the same module-scoped sharing inside a job, and `renderOrchestrator`'s outer `finally` still clears every entry it registered so the cache cannot grow monotonically across renders.
- `renderOrchestrator.ts`: imports the new helpers, drops the unused `readdirSync` import, updates inline comments, and replaces two `frameDirMaxIndexCache.delete` sites with `clearMaxFrameIndex`.
- New `frameDirCache.test.ts` (bun:test, 11 tests) covering:
  - Reading the max index from a populated directory.
  - Ignoring filenames that don't match `frame_NNNN.png` (wrong ext, wrong prefix, wrong case, double extension, empty index group, same-named subdirectory).
  - Empty- and missing-directory paths returning `0` and being cached.
  - Intra-job invariant: subsequent readdir mutations not observed once cached.
  - `clearMaxFrameIndex` forcing a re-read; returns `false` for paths that were never cached.
  - Per-directory isolation when multiple directories are registered.
  - The cross-job contract from Chunk 5B: cache empty between well-behaved jobs, doesn't grow monotonically across 20 simulated renders with 3 HDR videos each (steady-state cache size stays at 3), and a buggy job that forgets to clear leaks exactly its own entries rather than affecting unrelated jobs.

## Test plan

- [x] `frameDirCache.test.ts` 11/11 pass.
- [x] Existing producer tests unchanged.
- [x] Behavior preserved: same module-scoped sharing inside a job, same outer-`finally` eviction.

## Stack

Chunk 9E of `plans/hdr-followups.md`. Test-driven extraction; complements Chunk 5B.
2026-04-23 14:29:36 -07:00
..

@hyperframes/producer

Full HTML-to-video rendering pipeline: capture frames with Chrome's BeginFrame API, encode with FFmpeg, mix audio — all in one call.

Install

npm install @hyperframes/producer

Requirements: Node.js >= 22, Chrome/Chromium (auto-downloaded), FFmpeg

Usage

Render a video

import { createRenderJob, executeRenderJob } from "@hyperframes/producer";

const job = createRenderJob({
  inputPath: "./my-composition.html",
  outputPath: "./output.mp4",
  width: 1920,
  height: 1080,
  fps: 30,
});

const result = await executeRenderJob(job, (progress) => {
  console.log(`${Math.round(progress.percent * 100)}%`);
});

console.log(result.outputPath); // ./output.mp4

Run as an HTTP server

The producer can also run as a render server, accepting render requests over HTTP:

import { startServer } from "@hyperframes/producer";

await startServer({ port: 8080 });
// POST /render with a RenderConfig body

Configuration

RenderConfig controls the render pipeline:

Option Default Description
inputPath Path to the HTML composition
outputPath Output video file path
width 1920 Frame width in pixels
height 1080 Frame height in pixels
fps 30 Frames per second (24, 30, or 60)
quality "standard" Encoder preset ("draft", "standard", "high")

How it works

  1. Serve — spins up a local file server for the HTML composition
  2. Capture — opens the page in headless Chrome, seeks frame-by-frame via HeadlessExperimental.beginFrame, captures screenshots
  3. Encode — pipes frames through FFmpeg (with GPU encoder detection and chunked concat)
  4. Mix — extracts <audio> elements and mixes them into the final video
  5. Finalize — applies faststart for streaming-friendly MP4

Documentation

Full documentation: hyperframes.heygen.com/packages/producer