certwatch

SSL Certificate Watcher - monitors SSL/TLS certificate expiration dates.

Purpose

Track SSL certificate validity and expiration for domains. Provides renewal scheduling recommendations.

Installation

go build -o certwatch ./cmd/certwatch

Usage

certwatch <domain1> <domain2> ...

Examples

# Check single domain
certwatch example.com

# Check multiple domains
certwatch example.com api.example.com mail.example.com

# Check with specific ports
certwatch example.com:443

Output

=== CERTIFICATE WATCHER ===

Domain: example.com
Issuer: Let's Encrypt
Valid From: 2024-01-15
Valid Until: 2025-01-15
Days Remaining: 365
Status: OK

=== RENEWAL SCHEDULE ===
Recommended cron jobs for auto-renewal:

30 days before expiry:
  0 0 1 * * certbot renew --force-renewal

7 days before expiry:
  0 0 1 * * certbot renew

Status Levels

• OK: Certificate valid with >30 days remaining
• EXPIRING_SOON: Certificate valid with 7-30 days remaining
• CRITICAL: Certificate valid with <7 days remaining
• EXPIRED: Certificate has expired

Dependencies

• Go 1.21+
• github.com/fatih/color

Build and Run

# Build
go build -o certwatch ./cmd/certwatch

# Run
go run ./cmd/certwatch example.com api.example.com

License

MIT