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.
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! - 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.readthedocs.io/en/stable/schema.yamlschema version=Json schema version 7file 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
titleandmeta(arbitrary data) attributes are persisted when adding other resources withgoss 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: 4.4.0
# Loaded from --vars YAML/JSON file
{{.Vars.package}}:
installed: true
{{if eq .Env.OS "centos"}}
# This test is only when $OS environment variable is set to "centos"
libselinux:
installed: true
{{end}}
Goss.yaml files with templates can still be validated through the Json schema after being rendered
using the goss render command. See example below
$ cd docs
$ goss --vars ./vars.yaml render > rendered_goss.yaml
# proceed with json schema validation of rendered_goss.yaml in your favorite IDE
# or in one of the Json schema validator listed in https://json-schema.org/implementations.html
# The following example is for a Linux AMD64 host
$ curl -LO https://github.com/neilpa/yajsv/releases/download/v1.4.1/yajsv.linux.amd64
$ chmod a+x yajsv.linux.amd64
$ sudo mv yajsv.linux.amd64 /usr/sbin/yajsv
$ yajsv -s goss-json-schema.yaml rendered_goss.yaml
rendered_goss.yaml: fail: process.chrome: skip is required
rendered_goss.yaml: fail: service.sshd: skip is required
1 of 1 failed validation
rendered_goss.yaml: fail: process.chrome: skip is required
rendered_goss.yaml: fail: service.sshd: skip is required
JSON Schema maintains a table of validators.
Supported resources
- package - add new package
- file - add new file
- addr - add new remote address:port - ex: google.com:80
- port - add new listening [protocol]:port - ex: 80 or udp:123
- service - add new service
- user - add new user
- group - add new group
- command - add new command
- dns - add new dns
- process - add new process name
- kernel-param - add new kernel-param
- mount - add new mount
- interface - add new network interface
- http - add new network http url with proxy support
- goss - add new goss file, it will be imported from this one
- matching - test for matches in supplied content
Supported output formats
- rspecish - (default) Similar to rspec output
- documentation - Verbose test results
- json - JSON, detailed test result
- tap - TAP style
- junit - JUnit style
- nagios - Nagios/Sensu compatible output /w exit code 2 for failures.
- prometheus - Prometheus compatible output.
- silent - No output. Avoids exposing system information (e.g. when serving tests as a healthcheck endpoint).
Community Contributions
- goss-ansible - Ansible module for Goss.
- degoss - Ansible role for installing, running, and removing Goss in a single go.
- ansible-goss-install - Ansible role for installing Goss (option for install as user or root)
- kitchen-goss - A test-kitchen verifier plugin for Goss.
- goss-fpm-files - Might be useful for building goss system packages.
- packer-provisioner-goss - A packer plugin to run Goss as a provision step.
- gossboss - Collect and view aggregated Goss test results from multiple remote Goss servers.
Limitations
goss works well on Linux, but support on Windows & macOS is alpha. See platform-feature-parity.
The following tests have limitations.
Package:
- rpm
- deb
- Alpine apk
- pacman
Service:
- systemd
- sysV init
- OpenRC init
- Upstart
