Goss - Quick and Easy server validation

Goss in 45 seconds

Note: For testing containers see the dgoss wrapper. Also, user submitted wrapper scripts for Kubernetes kgoss and Docker Compose dcgoss.

Note: For some Docker/Kubernetes healthcheck, health endpoint, and container ordering examples, see my blog post [here][kubernetes-simplified-health-checks].

Introduction

What is Goss?

Goss is a YAML based serverspec alternative tool for validating a server's configuration. It eases the process of writing tests by allowing the user to generate tests from the current system state. Once the test suite is written they can be executed, waited-on, or served as a health endpoint.

Why use Goss?

Goss is EASY! - Goss in 45 seconds
Goss is FAST! - small-medium test suites are near instantaneous, see benchmarks
Goss is SMALL! - <10MB single self-contained binary

Installation

Note: For macOS and Windows, see: [platform-feature-parity].

This will install goss and dgoss.

Note: Using curl | sh is not recommended for production systems, use manual installation below.

# Install latest version to /usr/local/bin
curl -fsSL https://goss.rocks/install | sh

# Install v0.4.8 version to ~/bin
curl -fsSL https://goss.rocks/install | GOSS_VER=v0.4.8 GOSS_DST=~/bin sh

Manual installation

Latest

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

curl -L https://github.com/goss-org/goss/releases/latest/download/dgoss -o /usr/local/bin/dgoss
# Alternatively, using the latest master
# curl -L https://raw.githubusercontent.com/goss-org/goss/master/extras/dgoss/dgoss -o /usr/local/bin/dgoss
chmod +rx /usr/local/bin/dgoss

Specific Version

# See https://github.com/goss-org/goss/releases for release versions
VERSION=v0.4.8
curl -L "https://github.com/goss-org/goss/releases/download/${VERSION}/goss-linux-amd64" -o /usr/local/bin/goss
chmod +rx /usr/local/bin/goss

# (optional) dgoss docker wrapper (use 'master' for latest version)
VERSION=v0.4.8
curl -L "https://github.com/goss-org/goss/releases/download/${VERSION}/dgoss" -o /usr/local/bin/dgoss
chmod +rx /usr/local/bin/dgoss

Build it yourself

make build

Full Documentation

Using the container image

Using the Goss container image

Quick start

Writing a simple sshd test

An initial set of tests can be derived from the system state by using the add or autoadd commands.

Let's write a simple sshd test using autoadd.

# Running it as root will allow it to also detect ports
$ sudo goss autoadd sshd

Generated goss.yaml:

port:
  tcp:22:
    listening: true
    ip:
    - 0.0.0.0
  tcp6:22:
    listening: true
    ip:
    - '::'
service:
  sshd:
    enabled: true
    running: true
user:
  sshd:
    exists: true
    uid: 74
    gid: 74
    groups:
    - sshd
    home: /var/empty/sshd
    shell: /sbin/nologin
group:
  sshd:
    exists: true
    gid: 74
process:
  sshd:
    running: true

Now that we have a test suite, we can:

Run it once

$ goss validate
...............

Total Duration: 0.021s # <- yeah, it's that fast..
Count: 15, Failed: 0

Edit it to use templates, and run with a vars file

goss --vars vars.yaml validate

keep running it until the system enters a valid state or we timeout

goss validate --retry-timeout 30s --sleep 1s

serve the tests as a health endpoint

$ goss serve &
$ curl localhost:8080/healthz

# JSON endpoint
$ goss serve --format json &
$ curl localhost:8080/healthz

# rspecish response via content negotiation
$ goss serve --format json &
$ curl -H "Accept: application/vnd.goss-rspecish" localhost:8080/healthz

Manually editing Goss files

Goss files can be manually edited to improve readability and expressiveness of tests.

A Json draft 7 schema available at https://goss.rocks/schema.yaml makes it easier to edit simple goss.yaml files in IDEs, providing usual coding assistance such as inline documentation, completion and static analysis. See #793 for screenshots.

For example, to configure the Json schema in JetBrains intellij IDEA, follow documented instructions, with arguments such as:

schema url=https://goss.rocks/schema.yaml
schema version=Json schema version 7
file path pattern=*/goss.yaml

In addition, Goss files can also be further manually edited (without yet full json support) to use:

Patterns
Advanced Matchers
Templates
title and meta (arbitrary data) attributes are persisted when adding other resources with goss add

Some examples:

user:
  sshd:
    title: UID must be between 50-100, GID doesn't matter. home is flexible
    meta:
      desc: Ensure sshd is enabled and running since it's needed for system management
      sev: 5
    exists: true
    uid:
      # Validate that UID is between 50 and 100
      and:
        gt: 50
        lt: 100
    home:
      # Home can be any of the following
      or:
      - /var/empty/sshd
      - /var/run/sshd

package:
  kernel:
    installed: true
    versions:
      # Must have 3 kernels and none of them can be 4.4.0
      and:
      - have-len: 3
      - not:
          contain-element: