Add support for Fedora CoreOS

This commit is inspired by upstream docker#4808

libmachine/provision/fedora.go

@@ -23,3 +23,9 @@ type FedoraProvisioner struct {
 func (provisioner *FedoraProvisioner) String() string {
 	return "fedora"
 }
+
+func (provisioner *FedoraProvisioner) CompatibleWithHost() bool {
+	isFedora := provisioner.OsReleaseInfo.ID == provisioner.OsReleaseID
+	isCoreOS := provisioner.OsReleaseInfo.VariantID == "coreos"
+	return isFedora && !isCoreOS
+}

libmachine/provision/fedora_coreos.go

@@ -0,0 +1,138 @@
+package provision
+
+import (
+	"bytes"
+	"fmt"
+	"text/template"
+
+	"github.com/rancher/machine/libmachine/auth"
+	"github.com/rancher/machine/libmachine/drivers"
+	"github.com/rancher/machine/libmachine/engine"
+	"github.com/rancher/machine/libmachine/log"
+	"github.com/rancher/machine/libmachine/provision/pkgaction"
+	"github.com/rancher/machine/libmachine/swarm"
+)
+
+func init() {
+	Register("Fedora-CoreOS", &RegisteredProvisioner{
+		New: NewFedoraCoreOSProvisioner,
+	})
+}
+
+// NewFedoraCoreOSProvisioner creates a new provisioner for a driver
+func NewFedoraCoreOSProvisioner(d drivers.Driver) Provisioner {
+	return &FedoraCoreOSProvisioner{
+		NewSystemdProvisioner("fedora", d),
+	}
+}
+
+// FedoraCoreOSProvisioner is a provisioner based on the CoreOS provisioner
+type FedoraCoreOSProvisioner struct {
+	SystemdProvisioner
+}
+
+// String returns the name of the provisioner
+func (provisioner *FedoraCoreOSProvisioner) String() string {
+	return "Fedora CoreOS"
+}
+
+// SetHostname sets the hostname of the remote machine
+func (provisioner *FedoraCoreOSProvisioner) SetHostname(hostname string) error {
+	log.Debugf("SetHostname: %s", hostname)
+
+	command := fmt.Sprintf("sudo hostnamectl set-hostname %s", hostname)
+	if _, err := provisioner.SSHCommand(command); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// GenerateDockerOptions formats a systemd drop-in unit which adds support for
+// Docker Machine
+func (provisioner *FedoraCoreOSProvisioner) GenerateDockerOptions(dockerPort int) (*DockerOptions, error) {
+	var (
+		engineCfg bytes.Buffer
+	)
+
+	driverNameLabel := fmt.Sprintf("provider=%s", provisioner.Driver.DriverName())
+	provisioner.EngineOptions.Labels = append(provisioner.EngineOptions.Labels, driverNameLabel)
+
+	engineConfigTmpl := `[Service]
+ExecStart=
+ExecStart=/usr/bin/dockerd \\
+          --host=fd:// \\
+          --exec-opt native.cgroupdriver=systemd \\
+          --host=tcp://0.0.0.0:{{.DockerPort}} \\
+          --tlsverify \\
+          --tlscacert {{.AuthOptions.CaCertRemotePath}} \\
+          --tlscert {{.AuthOptions.ServerCertRemotePath}} \\
+          --tlskey {{.AuthOptions.ServerKeyRemotePath}}{{ range .EngineOptions.Labels }} \\
+          --label {{.}}{{ end }}{{ range .EngineOptions.InsecureRegistry }} \\
+          --insecure-registry {{.}}{{ end }}{{ range .EngineOptions.RegistryMirror }} \\
+          --registry-mirror {{.}}{{ end }}{{ range .EngineOptions.ArbitraryFlags }} \\
+          -{{.}}{{ end }} \\
+          \$OPTIONS
+Environment={{range .EngineOptions.Env}}{{ printf "%q" . }} {{end}}
+`
+
+	t, err := template.New("engineConfig").Parse(engineConfigTmpl)
+	if err != nil {
+		return nil, err
+	}
+
+	engineConfigContext := EngineConfigContext{
+		DockerPort:    dockerPort,
+		AuthOptions:   provisioner.AuthOptions,
+		EngineOptions: provisioner.EngineOptions,
+	}
+
+	t.Execute(&engineCfg, engineConfigContext)
+
+	return &DockerOptions{
+		EngineOptions:     engineCfg.String(),
+		EngineOptionsPath: provisioner.DaemonOptionsFile,
+	}, nil
+}
+
+// CompatibleWithHost returns whether or not this provisoner is compatible
+// with the target host
+func (provisioner *FedoraCoreOSProvisioner) CompatibleWithHost() bool {
+	isFedora := provisioner.OsReleaseInfo.ID == "fedora"
+	isCoreOS := provisioner.OsReleaseInfo.VariantID == "coreos"
+	return isFedora && isCoreOS
+}
+
+// Package installs a package on the remote host. The Fedora CoreOS provisioner
+// does not support (or need) any package installation
+func (provisioner *FedoraCoreOSProvisioner) Package(name string, action pkgaction.PackageAction) error {
+	return nil
+}
+
+// Provision provisions the machine
+func (provisioner *FedoraCoreOSProvisioner) Provision(swarmOptions swarm.Options, authOptions auth.Options, engineOptions engine.Options) error {
+	provisioner.SwarmOptions = swarmOptions
+	provisioner.AuthOptions = authOptions
+	provisioner.EngineOptions = engineOptions
+
+	if err := provisioner.SetHostname(provisioner.Driver.GetMachineName()); err != nil {
+		return err
+	}
+
+	if err := makeDockerOptionsDir(provisioner); err != nil {
+		return err
+	}
+
+	log.Debugf("Preparing certificates")
+	provisioner.AuthOptions = setRemoteAuthOptions(provisioner)
+
+	log.Debugf("Setting up certificates")
+	if err := ConfigureAuth(provisioner); err != nil {
+		return err
+	}
+
+	log.Debug("Configuring swarm")
+	err := configureSwarm(provisioner, swarmOptions, provisioner.AuthOptions)
+	return err
+}
+