hooks.apialerts.com

Free, open-source webhook testing tool. Generate a unique URL, inspect incoming requests, and toggle between success/failure responses to test your retry logic.

Live at hooks.apialerts.com | Built by API Alerts

Quick Start

docker compose up --build

Open http://localhost:8080. The app and Postgres run together, migrations run automatically, and data persists in a Docker volume.

Features

• Request inspector -- headers, body, query params, source IP for every request
• Response mode toggle -- 200, 201, 400, 401, 403, 404, 500, 503, or 35s timeout
• Custom response bodies -- each status code saves its own body override independently
• Transaction log -- plain text request/response view, copy or download as .txt
• Auto-refresh -- 30-second polling with countdown bar and manual refresh
• Test button -- send a sample request without leaving the browser
• Dark mode -- automatic, based on system preference
• No sign-up -- fully anonymous, endpoints expire after 7 days of inactivity

How It's Built

The goal is a single binary with zero runtime dependencies (besides Postgres) and zero JavaScript build tooling.

• Go + embedded assets -- HTML templates are defined inline in Go handler files using the standard library html/template package. Static assets (CSS, HTMX, favicon) are compiled into the binary via go:embed. No third-party template engine, no separate template files, no asset pipeline. Build it, ship it, run it.
• HTMX instead of a JS framework -- the request list polls via HTMX, request details load as HTML fragments, config saves via fetch. The entire frontend is server-rendered HTML with a few lines of vanilla JS. No React, no bundler, no node_modules.
• Tailwind CSS standalone CLI -- CSS is compiled by a single static binary, not a Node.js toolchain. The Docker build handles minification. In development, make dev runs a file watcher that rebuilds on template changes.
• Postgres + Goose -- pgx for queries, Goose for migrations. Migrations run automatically on every server start, so there's no manual migration step for self-hosters or contributors.
• Stateless -- no sessions, no auth, no cookies. Endpoints are identified by their slug and associated with the creator's IP for the sibling list. This makes it trivial to deploy on Cloud Run, Fly, or any container platform.

Self-Hosting

Docker Compose (recommended)

docker compose up --build -d

Runs the Go app and Postgres together. Data persists in a Docker volume. Migrations run automatically on startup.

To change the port:

PORT=8080 docker compose up --build -d

Update the ports mapping in docker-compose.yml to match: "8080:8080".

Docker (bring your own Postgres)

If you already have a Postgres instance:

docker build -t hooks .

docker run -p 8080:8080 \
  -e DATABASE_URL="postgres://user:pass@your-db:5432/hooks?sslmode=require" \
  -e BASE_URL="https://hooks.yourdomain.com" \
  hooks

The app creates its tables automatically on startup via Goose migrations. You just need an empty database.

VPS (DigitalOcean, Hetzner, etc.)

git clone https://github.com/apialerts/hooks.git
cd hooks
BASE_URL=https://hooks.yourdomain.com docker compose up --build -d

Point your domain's DNS to the server IP. Use a reverse proxy like Caddy or nginx for HTTPS. Caddy handles SSL certificates automatically:

# Caddyfile
hooks.yourdomain.com {
    reverse_proxy localhost:8080
}

Cloud Run

# Build and push
gcloud builds submit --tag gcr.io/YOUR_PROJECT/hooks --project YOUR_PROJECT

# Deploy
gcloud run deploy hooks \
  --image gcr.io/YOUR_PROJECT/hooks \
  --region us-central1 \
  --project YOUR_PROJECT \
  --allow-unauthenticated \
  --set-env-vars "DATABASE_URL=postgres://...,BASE_URL=https://hooks.yourdomain.com"

Cloud Run sets the PORT env var automatically. The app is stateless and scales to zero.

Connecting to Cloud SQL: Use the built-in Cloud SQL connector rather than a public IP:

gcloud run deploy hooks \
  --image gcr.io/YOUR_PROJECT/hooks \
  --region us-central1 \
  --project YOUR_PROJECT \
  --allow-unauthenticated \
  --add-cloudsql-instances YOUR_PROJECT:us-central1:YOUR_INSTANCE \
  --set-env-vars "DATABASE_URL=postgres://user:pass@/hooks?host=/cloudsql/YOUR_PROJECT:us-central1:YOUR_INSTANCE,BASE_URL=https://hooks.yourdomain.com"

Environment Variables

Variable	Default	Description
PORT	8080	Port the server listens on
DATABASE_URL	(see below)	Full Postgres connection string
DB_PORT	5432	Postgres port (only used when DATABASE_URL is not set)
DB_USER	--	Postgres user (only used when DATABASE_URL is not set)
DB_PASSWORD	--	Postgres password (only used when DATABASE_URL is not set)
DB_HOST	--	Postgres host (only used when DATABASE_URL is not set)
DB_NAME	--	Postgres database name (only used when DATABASE_URL is not set)
DB_SSLMODE	require	Postgres SSL mode (only used when DATABASE_URL is not set)
BASE_URL	http://localhost:{PORT}	Public-facing URL (used in templates and transaction logs)
KILL_SWITCH	false	Serve a maintenance page without connecting to the database (for abuse/outages)

How the connection string is built:

• If DATABASE_URL is set, it is used directly.
• If DB_USER, DB_PASSWORD, DB_HOST, and DB_NAME are all set, the connection string is built as: postgres://{user}:{password}@{host}:{DB_PORT}/{name}?sslmode={DB_SSLMODE}
• Otherwise, it defaults to: postgres://hooks:hooks@localhost:{DB_PORT}/hooks?sslmode=disable

Limits

• 5 endpoints per IP address
• 50 requests stored per endpoint
• 60 requests/minute rate limit per endpoint
• 256KB max request payload
• 7-day expiry from last activity

Contributing

See CONTRIBUTING.md.

Attribution

Built with:

• Chi -- HTTP router
• pgx -- PostgreSQL driver
• Goose -- database migrations
• HTMX -- frontend interactivity
• Tailwind CSS -- styling
• Petname -- URL slug generation

License

MIT