Merge pull request #206 from jakefhyde/40901-hostname-truncation

Add hostname override flag to create

commands/create.go

@@ -138,6 +138,11 @@ var (
 			Usage: "Use a custom provisioning script instead of installing docker",
 			Value: "",
 		},
+		cli.StringFlag{
+			Name:  "hostname-override",
+			Usage: "Specify hostname to use during cloud-init instead of default generated hostname",
+			Value: "",
+		},
 	}
 )
 
@@ -231,14 +236,15 @@ func cmdCreateInner(c CommandLine, api libmachine.API) error {
 	osFlag := drivers.DriverOSFlag(h.Driver)
 
 	customInstallScript := c.String("custom-install-script")
+	h.HostOptions.HostnameOverride = c.String("hostname-override")
 	if customInstallScript != "" {
 		h.HostOptions.CustomInstallScript = customInstallScript
 		h.HostOptions.AuthOptions = nil
 		h.HostOptions.EngineOptions = nil
 		h.HostOptions.SwarmOptions = nil
 
 		if userdataFlag != "" {
-			err = updateUserdataFile(driverOpts, name, userdataFlag, osFlag, customInstallScript)
+			err = updateUserdataFile(driverOpts, name, h.HostOptions.HostnameOverride, userdataFlag, osFlag, customInstallScript)
 			if err != nil {
 				return fmt.Errorf("[cmdCreateInner] could not alter cloud-init file: %v", err)
 			}
@@ -498,7 +504,7 @@ func gzipEncode(data []byte) (string, error) {
 // updateUserdataFile If the user has provided a userdata file, then we add the customInstallScript to their userdata file.
 // This assumes that the user-provided userdata file start with a shebang or `#cloud-config`
 // If the user has not provided any userdata file, then we set the customInstallScript as the userdata file.
-func updateUserdataFile(driverOpts *rpcdriver.RPCFlags, machineName, userdataFlag, osFlag, customInstallScript string) error {
+func updateUserdataFile(driverOpts *rpcdriver.RPCFlags, machineName, hostname, userdataFlag, osFlag, customInstallScript string) error {
 	var userdataContent []byte
 	var err error
 	userdataFile := driverOpts.String(userdataFlag)
@@ -508,13 +514,13 @@ func updateUserdataFile(driverOpts *rpcdriver.RPCFlags, machineName, userdataFla
 		// Always convert to cloud config if user data is not provided
 		userdataContent = []byte("#cloud-config")
 	} else {
-		userdataContent, err = ioutil.ReadFile(userdataFile)
+		userdataContent, err = os.ReadFile(userdataFile)
 		if err != nil {
 			return err
 		}
 	}
 
-	customScriptContent, err := ioutil.ReadFile(customInstallScript)
+	customScriptContent, err := os.ReadFile(customInstallScript)
 	if err != nil {
 		return err
 	}
@@ -527,7 +533,7 @@ func updateUserdataFile(driverOpts *rpcdriver.RPCFlags, machineName, userdataFla
 	}
 	defer modifiedUserdataFile.Close()
 
-	if err := replaceUserdataFile(machineName, machineOS, userdataContent, customScriptContent, modifiedUserdataFile); err != nil {
+	if err := replaceUserdataFile(machineName, machineOS, hostname, userdataContent, customScriptContent, modifiedUserdataFile); err != nil {
 		return err
 	}
 
@@ -540,7 +546,7 @@ func updateUserdataFile(driverOpts *rpcdriver.RPCFlags, machineName, userdataFla
 // and passes the script path to commonCloudConfig
 // RK - sets the hostname based on OS as cloud-init (linux) and cloudbase-init (windows) diverge
 // on how hostnames are set in cloud-config (userdata)
-func writeCloudConfig(machineName, encodedData, machineOS string, cf map[interface{}]interface{}, newUserDataFile *os.File) error {
+func writeCloudConfig(machineName, encodedData, machineOS, hostname string, cf map[interface{}]interface{}, newUserDataFile *os.File) error {
 	command := "sh"
 	path := "/usr/local/custom_script/install.sh"
 	key := "hostname"
@@ -555,7 +561,11 @@ func writeCloudConfig(machineName, encodedData, machineOS string, cf map[interfa
 		key = "set_hostname"
 	}
 	if _, ok := cf[key]; !ok {
-		cf[key] = machineName
+		if hostname != "" {
+			cf[key] = hostname
+		} else {
+			cf[key] = machineName
+		}
 		log.Debugf("[writeCloudConfig] wrote %s field for %s machine %s", key, machineOS, machineName)
 	}
 	return commonCloudConfig(encodedData, command, path, cf, newUserDataFile)
@@ -598,7 +608,7 @@ func commonCloudConfig(encodedData, command, path string, cf map[interface{}]int
 // temp file for this content.
 // If the user-provided userdata file starts with a shebang, then we can add it to the customScriptContent and add data to the `runcmd` directive.
 // fi the user-provided userdata file is in cloud-config format, then we add the customScriptContent to the `runcmd` directive.
-func replaceUserdataFile(machineName, machineOS string, userdataContent, customScriptContent []byte, newUserDataFile *os.File) error {
+func replaceUserdataFile(machineName, machineOS, hostname string, userdataContent, customScriptContent []byte, newUserDataFile *os.File) error {
 	var err error
 	var encodedData string
 	cf := make(map[interface{}]interface{})
@@ -632,7 +642,7 @@ func replaceUserdataFile(machineName, machineOS string, userdataContent, customS
 		return fmt.Errorf("existing userdata file does not begin with '#!' or '#cloud-config'")
 	}
 
-	return writeCloudConfig(machineName, encodedData, machineOS, cf, newUserDataFile)
+	return writeCloudConfig(machineName, encodedData, machineOS, hostname, cf, newUserDataFile)
 }
 
 // appendValueToListInCloudConfig appends a value to a list or creates one if it does not exist at the given key within the cloud config

libmachine/host/host.go

@@ -53,6 +53,7 @@ type Options struct {
 	Memory              int
 	Disk                int
 	CustomInstallScript string
+	HostnameOverride    string
 	MachineOS           string
 	EngineOptions       *engine.Options
 	SwarmOptions        *swarm.Options
@@ -303,7 +304,7 @@ func (h *Host) Provision() error {
 
 	if h.HostOptions.CustomInstallScript != "" {
 		log.Infof("Machine %s was provisioned with a custom install script, using this script for provisioning", h.Name)
-		return provision.WithCustomScript(provisioner, h.HostOptions.CustomInstallScript)
+		return provision.WithCustomScript(provisioner, h.HostOptions.CustomInstallScript, h.HostOptions.HostnameOverride)
 	}
 
 	return provisioner.Provision(*h.HostOptions.SwarmOptions, *h.HostOptions.AuthOptions, *h.HostOptions.EngineOptions)

libmachine/libmachine.go

@@ -177,7 +177,7 @@ func (api *Client) performCreate(h *host.Host) error {
 	log.Infof("Provisioning with %s...", provisioner.String())
 	if h.HostOptions.CustomInstallScript != "" {
 		log.Infof("Provisioning with custom install script via SSH, not installing Docker...")
-		return provision.WithCustomScript(provisioner, h.HostOptions.CustomInstallScript)
+		return provision.WithCustomScript(provisioner, h.HostOptions.CustomInstallScript, h.HostOptions.HostnameOverride)
 	} else {
 		if err := provisioner.Provision(*h.HostOptions.SwarmOptions, *h.HostOptions.AuthOptions, *h.HostOptions.EngineOptions); err != nil {
 			return err

libmachine/provision/custom_script.go

@@ -2,17 +2,21 @@ package provision
 
 import (
 	"fmt"
-	"io/ioutil"
+	"os"
 
 	"github.com/rancher/machine/libmachine/provision/pkgaction"
 )
 
-func WithCustomScript(provisioner Provisioner, customScriptPath string) error {
+func WithCustomScript(provisioner Provisioner, customScriptPath, hostname string) error {
 	if provisioner == nil {
 		return nil
 	}
 
-	if err := provisioner.SetHostname(provisioner.GetDriver().GetMachineName()); err != nil {
+	if hostname == "" {
+		hostname = provisioner.GetDriver().GetMachineName()
+	}
+
+	if err := provisioner.SetHostname(hostname); err != nil {
 		return err
 	}
 
@@ -22,7 +26,7 @@ func WithCustomScript(provisioner Provisioner, customScriptPath string) error {
 		}
 	}
 
-	customScriptContents, err := ioutil.ReadFile(customScriptPath)
+	customScriptContents, err := os.ReadFile(customScriptPath)
 	if err != nil {
 		return fmt.Errorf("unable to read file %s: %v", customScriptPath, err)
 	}