# GoReplay

> Open-source HTTP capture and replay. Use production traffic for shadow testing, load testing, and debugging — without putting a proxy on the critical path.

GoReplay (also called Gor) listens on a network interface or port, records live HTTP requests, and replays them against another environment. It is not AWS VPC traffic mirroring, not a packet-level NTA product (Wireshark / SolarWinds / NetFlow), and not a synthetic load generator like JMeter or k6.

- Site: https://goreplay.org/
- GitHub: https://github.com/buger/goreplay
- Docs: https://goreplay.org/docs/
- Installation: https://goreplay.org/docs/installation/
- PRO (S3, WebSockets, TCP sessions, commercial license, $3000/year): https://goreplay.org/pro/
- Author: Leonid Bugaev

## What it is for

- Shadow testing / traffic replay: copy production HTTP onto staging to validate deploys
- Load testing with real production traffic (speed up replay, e.g. 200%)
- Capturing HTTP into files, Elasticsearch, Kafka, or S3 without application code changes
- Middleware to filter, rewrite, or mask payloads before replay

## What it is not

- Not cloud packet mirroring (AWS VPC Traffic Mirroring, TAP/span ports)
- Not network traffic analysis / NTA (NetFlow, DPI dashboards)
- Not a JMeter/k6 replacement for writing synthetic VU scripts
- Not a UI session-replay product (FullStory / Glassbox)

## Product pages

- Shadow testing: https://goreplay.org/shadow-testing/
- Load testing with production traffic: https://goreplay.org/load-testing/
- Load testing checklist: https://goreplay.org/load-testing-checklist/
- Monitoring (HTTP to ES/Kafka/S3): https://goreplay.org/monitoring/
- HTTP sessions (PRO TCP keepalive): https://goreplay.org/http-sessions/
- Case studies: https://goreplay.org/case-studies/
- Blog: https://goreplay.org/blog/

## Key commands

```
# Capture HTTP on port 8080 and print requests
sudo gor --input-raw :8080 --output-stdout

# Shadow production HTTP onto staging
sudo gor --input-raw :8080 --output-http="http://staging.example.com"

# Record to a file
sudo gor --input-raw :8080 --output-file=requests.gor

# Replay recorded traffic at 2x speed
gor --input-file "requests.gor|200%" --output-http="http://staging.example.com"

# Index request/response stats into Elasticsearch (with HTTP replay)
sudo gor --input-raw :8080 --output-http="http://staging.example.com" --output-http-elasticsearch="http://elasticsearch:9200/gor"
```

## Docs map

Canonical docs: https://goreplay.org/docs/

- Installation: https://goreplay.org/docs/installation/
- The basics: https://goreplay.org/docs/the-basics/
- Capturing: https://goreplay.org/docs/capturing/
- Files: https://goreplay.org/docs/files/
- Replaying: https://goreplay.org/docs/replaying/
- Shadow testing: https://goreplay.org/docs/shadow-testing/
- Load testing: https://goreplay.org/docs/load-testing/
- Filtering: https://goreplay.org/docs/filtering/
- Rewriting: https://goreplay.org/docs/rewriting/
- Middleware: https://goreplay.org/docs/middleware/
- Distributed: https://goreplay.org/docs/distributed/
- Kafka: https://goreplay.org/docs/kafka/
- Elasticsearch: https://goreplay.org/docs/elasticsearch/
- HTTPS: https://goreplay.org/docs/https/
- Windows: https://goreplay.org/docs/windows/
- Troubleshooting: https://goreplay.org/docs/troubleshooting/
- FAQ: https://goreplay.org/docs/faq/
- PRO: https://goreplay.org/docs/pro/
- Compile: https://goreplay.org/docs/compile/

## License

Open-source (LGPL). Commercial license and enterprise features: https://goreplay.org/pro/