snago

README

snago — HTTP request capture & replay tool

Capture, inspect, and replay HTTP requests. Point your webhooks or API calls at snago, and it saves every incoming request to disk. Replay them later against any target — original or different — with headers, body, and query strings fully preserved.

Single binary, zero runtime dependencies.

Use cases

• Webhook development — Capture GitHub/Stripe/Slack webhooks locally, inspect payloads, and replay them while iterating on your handler.
• API debugging — Record requests from a client, inspect what was actually sent, and replay to reproduce issues.
• Request archiving — Persist incoming traffic for later analysis without modifying your application.

Install

go install github.com/nikooo777/snago@latest

Or build from source:

git clone https://github.com/nikooo777/snago.git
cd snago
make build

Quick start

# 1. Start capturing on port 8080
snago serve

# 2. Send a request (from another terminal)
curl -X POST -H "Content-Type: application/json" \
  -d '{"event":"push"}' http://localhost:7624/webhooks/github

# 3. Inspect the captured request
snago inspect captures/<file>.gob

# 4. Replay it to your real server
snago replay --target http://localhost:9090 captures/<file>.gob

Commands

snago serve

Start an HTTP server that captures every incoming request to a .gob file. All requests receive a 200 OK response with body ok — it acts as a universal sink.

snago serve [--addr :7624] [--dir ./captures] [--verbose]

Flag	Default	Description
--addr	:7624	Listen address
--dir	./captures	Output directory for captured .gob files
--verbose	false	Print full request details (headers + body) for each capture

Example output:

$ snago serve
INFO snago listening addr=:7624 dir=./captures
INFO request captured method=POST path=/webhooks/github headers=5 body=66b file=1771366415797329694_38aab851.gob
INFO request captured method=GET path=/api/health headers=2 body=0b file=1771366415801479108_bd746ac6.gob

The server shuts down gracefully on Ctrl+C. If running behind a reverse proxy, it reads X-Forwarded-Proto to detect the original scheme (http/https).

snago inspect

Pretty-print a captured request — method, URL, timestamp, headers, and body.

snago inspect <file.gob>

$ snago inspect captures/1771366415797329694_38aab851.gob
POST https://example.com/webhooks/github
Captured: 2026-02-17 23:15:56

Content-Type: application/json
X-GitHub-Event: push

{"ref":"refs/heads/main","commits":[{"message":"initial commit"}]}

snago replay

Re-send a captured request. By default, replays to the original host. Use --target to redirect it.

snago replay [--target URL] <file.gob>

Flag	Default	Description
--target	(original host)	Override destination URL (scheme://host)

# Replay to original destination
snago replay captures/1771366415797329694_38aab851.gob

# Replay to a different host (path and query string are preserved)
snago replay --target http://localhost:9090 captures/1771366415797329694_38aab851.gob

Hop-by-hop headers (Connection, Transfer-Encoding, Content-Length) are automatically stripped before sending.

snago version

snago version
# or
snago --version

Environment variables

All flags can be set via environment variables (flags take precedence when both are set):

Variable	Flag equivalent	Default
SNAGO_SERVE_ADDR	--addr	:7624
SNAGO_SERVE_DIR	--dir	./captures
SNAGO_SERVE_VERBOSE	--verbose	false
SNAGO_REPLAY_TARGET	--target	(empty)

Shell completion

Snago supports shell completion via Cobra:

# Bash
snago completion bash > /etc/bash_completion.d/snago

# Zsh
snago completion zsh > "${fpath[1]}/_snago"

# Fish
snago completion fish > ~/.config/fish/completions/snago.fish

License

MIT