Simulating Network Conditions with JavaScript

on YouTube ↗36m

" summary

Built a containerized TypeScript proxy that uses Deno and the Streams API to insert a transform-stream throttle between a headless-browser runner and a static file server, letting tests inject latency, jitter, 404s or hangs and verify player metrics. A 5‑minute multi-bitrate test asset totals ~5 GB; a demo shows the player estimating 6 Mbps when the proxy is set to 6 Mbps. The throttle is open source as bandwidth-throttle-stream and aims to run thousands of parallel CI simulations.

AI-written summary · about

" chapters (9)

1. 0:00Introduction and speaker background
2. 3:50Why build custom network simulation tools
3. 7:17Architecture and Docker setup
4. 10:25Implementing bandwidth throttling
5. 18:23Proxy request lifecycle
6. 20:07Demo of the network simulation tool
7. 23:34Automated testing with JSON configs
8. 24:58Beyond video playback use cases
9. 26:22Q&A session

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