goss

Goss - Server Validation Tool

YAML-based server testing/validation tool. Single Go binary, no dependencies. Generates tests from current system state via goss add/goss autoadd.

Installation

# Binary install
curl -L https://github.com/goss-org/goss/releases/latest/download/goss-linux-amd64 -o /usr/local/bin/goss
chmod +rx /usr/local/bin/goss

# dgoss (Docker wrapper)
curl -L https://raw.githubusercontent.com/goss-org/goss/master/extras/dgoss/dgoss -o /usr/local/bin/dgoss
chmod +rx /usr/local/bin/dgoss

CLI Quick Reference

Command	Alias	Purpose
goss validate	goss v	Run tests, show results
goss serve	goss s	Expose health endpoint (default :8080/healthz)
goss add <type> <name>	goss a	Add single resource test
goss autoadd <name>	goss aa	Auto-discover all resources for a service
goss render	goss r	Render gossfile with includes/templates

Common Flags

goss validate --format documentation   # verbose output
goss validate --retry-timeout 30s      # retry for 30s (startup waits)
goss validate -g custom.yaml           # custom gossfile
goss validate --vars vars.yaml         # template variables
goss serve --listen-addr 0.0.0.0:9000 --format json --cache 30s

Output Formats

rspecish (default), documentation, json, junit, tap, nagios, prometheus, silent

Resource Types

Type	Key Attributes	Notes
file	exists, mode, owner, group, contents, filetype, sha256	Supports checksums, symlink targets
package	installed, versions	Use --package flag for manager type
service	enabled, running	systemd/init
port	listening, ip	Format: tcp:22:, tcp6:22:, udp:53:
process	running	Match by command name
command	exit-status, stdout, stderr, timeout	Default timeout 10s (in ms)
user	exists, uid, gid, groups, home, shell
group	exists, gid
dns	resolvable, addrs, server	Record types: A, AAAA, CNAME, MX, etc.
http	status, body, headers, allow-insecure	Auth, TLS certs, proxy support
addr	reachable, timeout	Remote TCP/UDP reachability
mount	exists, filesystem, source, opts, usage	defaults is fstab alias, not actual opt
kernel-param	value	sysctl parameters
interface	exists, addrs, mtu	Network interfaces
gossfile	(import)	Include other gossfiles, supports globs
matching	content, matches	Best with templates for complex assertions

Gossfile Structure

# Multiple resources consolidated under single type key
# YAML overwrites duplicate keys - never declare same type twice
package:
  nginx: {installed: true}
  curl: {installed: true}

service:
  nginx:
    enabled: true
    running: true

port:
  tcp:80:
    listening: true
  tcp:443:
    listening: true

file:
  /etc/nginx/nginx.conf:
    exists: true
    mode: "0644"
    owner: root

# Import other gossfiles
gossfile:
  goss.d/*.yaml: {}

Reference Files

File	Content
references/matchers.md	Pattern matching, regex, numeric/array/logical matchers, gjson
references/templating.md	Go templates, Sprig functions, variables, conditionals
references/containers.md	dgoss (Docker), kgoss (Kubernetes), dcgoss (docker-compose)
references/patterns.md	Modular gossfiles, retry/wait patterns, health endpoints, gotchas

Cross-References

• Docker images: Use docker skill for Dockerfile writing, then goss dgoss for validation
• Kubernetes: Use k3s skill for cluster setup, then goss kgoss for pod validation
• CI/CD: Use gitlab-ci or github skills for pipeline integration with goss validate --format junit