Development Environment

To develop and test the Warewulf server, you need a single system (typically a virtual machine) to serve as a test server deployment. To actually test provisioning, your development server also needs a dedicated network that it can run DHCP on. This can typically be provisioned as a virtual network bridge in virtual machine software.

Options include:

• KVM / Libvirt

• VirtualBox

• VMWare

• UTM

A Warewulf development environment should likely use Rocky Linux 9 or openSUSE LEAP 15, though there are ongoing development efforts using Debian and Ubuntu as well.

Compiling Warewulf for a Development Server

# Rocky Linux 9
dnf -y install git epel-release golang {libassuan,gpgme}-devel unzip tftp-server dhcp-server nfs-utils squashfs-tools ipxe-bootimgs-{x86,aarch64}

git clone https://github.com/warewulf/warewulf.git
cd warewulf
env \
  PREFIX=/opt/warewulf \
  SYSCONFDIR=/etc \
  IPXESOURCE=/usr/share/ipxe \
  WWPROVISIONDIR=/opt/warewulf/provision \
  WWOVERLAYDIR=/opt/warewulf/overlays \
  WWCHROOTDIR=/opt/warewulf/chroots \
  make all
make install

These paths balance isolation (e.g., installing binaries in /opt/warewulf/bin/) with integration (e.g., storing configuration in /etc/warewulf/ and using local Dracut and iPXE paths).

After making changes to the source, simply running make install should be enough to update installed binaries.

You should likely also disable any local firewall. Otherwise, consult the general installation guide for configuration details.

systemctl disable --now firewalld

Running the Test Suite

Warewulf includes an ever-growing test suite. Alias targets in the Makefile support running it quickly, easily, and consistently.

make test

Additional tests exist as well to perform various checks on the golang source. These checks are run automatically by GitHub as part of the Warewulf CI process; but it is a good idea to run them locally before submitting a new PR.

make vet
make staticcheck
make lint

New code, and code changes, should often be accompanied by updates to the test suite.

More information:

• The golang testing package

• Table Driven Tests

• Testify assert

• Warewulf testenv

Writing Tests

New functionality needs tests, and a bug fix should include a test that fails without the fix. Tests are table-driven and use testify assert.

Tests that touch configuration, overlays, or images use internal/pkg/testenv. It creates a temporary Warewulf tree with its own nodes.conf and warewulf.conf and points Warewulf’s paths at it. (The separate warewulf-testenv repository is a virtual test cluster, not this package.)

env := testenv.New(t)
defer env.RemoveAll()
env.WriteFile("etc/warewulf/nodes.conf", `nodes:
  n1: {}`)

WriteFile, ImportFile, and ImportDir populate the tree; ReadFile and GetPath inspect it. After rewriting warewulf.conf, call env.Configure() so Warewulf re-reads it.

To test a wwctl subcommand, run its GetCommand() with arguments and check the result. internal/app/wwctl/node/set/main_test.go is a complete example; it calls warewulfd.SetNoDaemon() so the command does not try to reach a running daemon.

To test an overlay template, add a case to overlays/<name>/internal/<name>_test.go. Each test imports the template into a testenv, renders it for a node with wwctl overlay show --render, and compares the log output with an expected string. overlays/hostname/internal/hostname_test.go is the smallest example. When a template can abort, include a case for it. An aborted template with no output before the abort logs:

backupFile: true
writeFile: false

Aborted

Take expected output from a test run rather than writing it by hand.

Run one package’s tests with TZ=UTC go test ./internal/pkg/overlay/... (after make config), or the whole suite with make test.

Using a Dev Container

Visual Studio Code (VSC) can utilize a Dev Container for a self-contained environment that has all the necessary tools and dependencies to build and test Warewulf. The Dev Container is based on the Rocky 9 image and is built using the devcontainer.json file in the .devcontainer directory of the Warewulf repository. To use this, working Docker/Podman and VSC installations are required. To use the Dev Container, click the “Open a Remote Window” button on the bottom left of the editor (>< icon) and select “Reopen in Container”. This will build the container and open a new VSC window with the container as the development environment.

Using Vagrant and Libvirt

Vagrant can be used to quickly spin up a test/development environment for Warewulf. A Vagrantfile is provided in the vagrant directory of the Warewulf repository. See the README.md for more details.