# Testing Standards in K3s Testing in K3s comes in 5 forms: - [Unit](#unit-tests) - [Integration](#integration-tests) - [Smoke](#smoke-tests) - [Performance](#performance) - [End-to-End (E2E)](#end-to-end-e2e-tests) This document will explain *when* each test should be written and *how* each test should be generated, formatted, and run. Note: all shell commands given are relative to the root k3s repo directory. ___ ## Unit Tests Unit tests should be written when a component or function of a package needs testing. Unit tests should be used for "white box" testing. ### Framework All unit tests in K3s follow a [Table Driven Test](https://github.com/golang/go/wiki/TableDrivenTests) style. Specifically, K3s unit tests are automatically generated using the [gotests](https://github.com/cweill/gotests) tool. This is built into the Go vscode extension, has documented integrations for other popular editors, or can be run via command line. Additionally, a set of custom templates are provided to extend the generated test's functionality. To use these templates, call: ```bash gotests --template_dir=/contrib/gotests_templates ``` Or in vscode, edit the Go extension setting `Go: Generate Tests Flags` and add `--template_dir=/contrib/gotests_templates` as an item. To facilitate unit test creation, see `tests/util/runtime.go` helper functions. ### Format All unit tests should be placed within the package of the file they test. All unit test files should be named: `_test.go`. All unit test functions should be named: `Test_Unit` or `Test_Unit_`. See the [etcd unit test](../pkg/etcd/etcd_test.go) as an example. ### Running ```bash go test ./pkg/... -run Unit ``` Note: As unit tests call functions directly, they are the primary drivers of K3s's code coverage metric. ___ ## Integration Tests Integration tests should be used to test a specific functionality of k3s that exists across multiple Go packages, either via exported function calls, or more often, CLI comands. Integration tests should be used for "black box" testing. See [integration/README.md](./integration/README.md) for more info. ___ ## Smoke Tests Smoke tests are a collection of tests defined under the [tests](../tests) path at the root of this repository. The sub-directories therein contain fixtures for running simple clusters to assert correct behavior for "happy path" scenarios. These fixtures are mostly self-contained Vagrantfiles describing single-node installations that are easily spun up with Vagrant for the `libvirt` and `virtualbox` providers: - [Install Script](../tests/install) :arrow_right: on proposed changes to [install.sh](../install.sh) - [CentOS 7](../tests/install/centos-7) (stand-in for RHEL 7) - [CentOS 8](../tests/install/centos-8) (stand-in for RHEL 8) - [Leap 15.3](../tests/install/opensuse-microos) (stand-in for SLES) - [MicroOS](../tests/install/opensuse-microos) (stand-in for SLE-Micro) - [Ubuntu 20.04](../tests/install/ubuntu-focal) (Focal Fossa) - [Control Groups](../tests/cgroup) :arrow_right: on any code change - [mode=unified](../tests/cgroup/unified) (cgroups v2) - [Fedora 34](../tests/cgroup/unified/fedora-34) (rootfull + rootless) - [Snapshotter](../tests/snapshotter/btrfs/opensuse-leap) :arrow_right: on any code change - [BTRFS](../tests/snapshotter/btrfs) ([containerd built-in](https://github.com/containerd/containerd/tree/main/snapshots/btrfs)) - [Leap 15.3](../tests/snapshotter/btrfs/opensuse-leap) When adding new installer test(s) please copy the prevalent style for the `Vagrantfile`. Ideally, the boxes used for additional assertions will support the default `virtualbox` provider which enables them to be used by our Github Actions Workflow(s). See: - [cgroup.yaml](../.github/workflows/cgroup.yaml). - [install.yaml](../.github/workflows/install.yaml). ### Framework If you are new to Vagrant, Hashicorp has written some pretty decent introductory tutorials and docs, see: - https://learn.hashicorp.com/collections/vagrant/getting-started - https://www.vagrantup.com/docs/installation #### Plugins and Providers The `libvirt` and `vmware_desktop` providers cannot be used without first [installing the relevant plugins](https://www.vagrantup.com/docs/cli/plugin#plugin-install) which are [`vagrant-libvirt`](https://github.com/vagrant-libvirt/vagrant-libvirt) and [`vagrant-vmware-desktop`](https://www.vagrantup.com/docs/providers/vmware/installation), respectively. Much like the default [`virtualbox` provider](https://www.vagrantup.com/docs/providers/virtualbox) these will do nothing useful without also installing the relevant server runtimes and/or client programs. #### Environment Variables These can be set on the CLI or exported before invoking Vagrant: - `TEST_VM_CPUS` (default :arrow_right: 2)
The number of vCPU for the guest to use. - `TEST_VM_MEMORY` (default :arrow_right: 2048)
The number of megabytes of memory for the guest to use. - `TEST_VM_BOOT_TIMEOUT` (default :arrow_right: 600)
The time in seconds that Vagrant will wait for the machine to boot and be accessible. ### Running The **Install Script** tests can be run by changing to the fixture directory and invoking `vagrant up`, e.g.: ```shell cd tests/install/centos-8 vagrant up # the following provisioners are optional. the do not run by default but are invoked # explicitly by github actions workflow to avoid certain timeout issues on slow runners vagrant provision --provision-with=k3s-wait-for-node vagrant provision --provision-with=k3s-wait-for-coredns vagrant provision --provision-with=k3s-wait-for-local-storage vagrant provision --provision-with=k3s-wait-for-metrics-server vagrant provision --provision-with=k3s-wait-for-traefik vagrant provision --provision-with=k3s-status vagrant provision --provision-with=k3s-procps ``` The **Control Groups** and **Snapshotter** tests require that k3s binary is built at `dist/artifacts/k3s`. They are invoked similarly, i.e. `vagrant up`, but with different sets of named shell provisioners. Take a look at the individual Vagrantfiles and/or the Github Actions workflows that harness them to get an idea of how they can be invoked. ___ ## Performance Tests Performance tests use Terraform to test large scale deployments of K3s clusters. See [perf/README.md](./perf/README.md) for more info. ___ ## End-to-End (E2E) Tests E2E tests cover multi-node K3s configuration and administration: bringup, update, teardown etc. across a wide range of operating systems. E2E tests are run nightly as part of K3s quality assurance (QA). See [e2e/README.md](./e2e/README.md) for more info. ___ ## Contributing New Or Updated Tests We gladly accept new and updated tests of all types. If you wish to create a new test or update an existing test, please submit a PR with a title that includes the words ` (Created/Updated)`.