Send Notification to Slack - Knative Function

A Knative function that receives CloudEvents and sends them to Slack. Built with FastAPI and uvicorn.

Development Quick Start

1. Setup (with UV)

# Clone and setup
uv sync

# Optional: Configure Slack (function works without it)
cp .env.example .env
# Edit .env with your Slack webhook URL

# Run locally
uv run python func.py

2. Test

curl -X POST http://localhost:8080/ \
  -H "Content-Type: application/json" \
  -H "ce-specversion: 1.0" \
  -H "ce-type: com.example.test" \
  -H "ce-source: test/source" \
  -H "ce-id: 123" \
  -d '{"message": "Hello CloudEvents!"}'

3. Docker

# Build and run
docker build -t send-notification-to-slack .
docker run -p 8080:8080 send-notification-to-slack

# Or use pre-built image from GHCR
docker run -p 8080:8080 ghcr.io/mneagul/send-notification-to-slack:latest

Configuration

Slack Setup (Optional)

1. Create a Slack app at https://api.slack.com/apps
2. Enable "Incoming Webhooks"
3. Set environment variables:

SLACK_WEBHOOK_URL=https://hooks.slack.com/services/YOUR/WEBHOOK/URL
SLACK_CHANNEL=#your-channel
SLACK_DATA_LIMIT=256  # Character limit for event data

Environment Variables

Variable	Default	Description
SLACK_WEBHOOK_URL	None	Slack webhook URL (optional)
SLACK_CHANNEL	None	Override webhook default channel
SLACK_USERNAME	"CloudEvent Bot"	Bot username
SLACK_ICON_EMOJI	":cloud:"	Bot icon
SLACK_DATA_LIMIT	256	Max characters for event data

Endpoints

• GET /health - Health check
• GET /ready - Readiness check
• POST / - CloudEvent handler

Knative Deployment

# Update func.yaml with your registry
func deploy

Features

• Receives any CloudEvent type
• Optional Slack notifications with data truncation
• Health/readiness endpoints for Kubernetes
• Comprehensive logging
• Multi-platform Docker builds via GitHub Actions