UpNotif - URL Uptime Monitor

A lightweight Rust application that monitors URL uptime and sends Slack notifications when status changes occur.

Features

• Monitors multiple URLs for 2xx HTTP responses
• Uses rustls for maximum platform independence
• Sends Slack webhook notifications on status changes
• Reports initial status on startup
• Configurable check intervals
• Built with musl for static linking

Environment Variables

• UPNOTIF_URLS - Comma-separated list of URLs to monitor (required)
• UPNOTIF_SLACK_WEBHOOK - Slack webhook URL for notifications, or "test" for console output (required)
• UPNOTIF_INTERVAL_SECONDS - Check interval in seconds (optional, defaults to 60)

Test Mode

Set UPNOTIF_SLACK_WEBHOOK=test to run in test mode. Instead of sending notifications to Slack, all messages will be logged to the console. This is useful for:

• Testing the application before deploying
• Development and debugging
• Running without a Slack webhook

Usage

Production:

export UPNOTIF_URLS="https://example.com,https://google.com"
export UPNOTIF_SLACK_WEBHOOK="https://hooks.slack.com/services/YOUR/WEBHOOK/URL"
export UPNOTIF_INTERVAL_SECONDS=30

./upnotif

Test mode:

export UPNOTIF_URLS="https://example.com,https://google.com"
export UPNOTIF_SLACK_WEBHOOK="test"
export UPNOTIF_INTERVAL_SECONDS=10

./upnotif
# Output will be logged to console instead of sent to Slack
# The program logs at INFO level by default - no need to set RUST_LOG

Building

For current platform (Mac/Windows/Linux):

cargo build --release

Binary will be in target/release/upnotif (or upnotif.exe on Windows).

For Linux musl (static binary):

# Install musl target
rustup target add x86_64-unknown-linux-musl

# Build static binary
cargo build --release --target x86_64-unknown-linux-musl

Binary will be in target/x86_64-unknown-linux-musl/release/upnotif and can run on any Linux system without dependencies.

Platform-specific notes:

• Mac: Use the default build - it will create a native binary with system dependencies
• Linux: Use musl target for maximum portability
• Windows: Default build works fine

Docker

Building and running with Docker:

# Build the Docker image
docker build -t upnotif .

# Run the container
docker run --rm \
  -e UPNOTIF_URLS="https://example.com,https://google.com" \
  -e UPNOTIF_SLACK_WEBHOOK="https://hooks.slack.com/services/YOUR/WEBHOOK/URL" \
  -e UPNOTIF_INTERVAL_SECONDS=30 \
  upnotif

Using Docker Compose:

# Edit docker-compose.yml with your environment variables
docker-compose up -d

The multi-stage Dockerfile:

1. Build stage: Uses Rust Alpine image to compile the application with musl
2. Runtime stage: Uses scratch base (minimal possible image) with only the static binary
3. Final image is extremely small (~10MB) and runs anywhere