Support reloading config during system containers start up

cmd/sysinit/sysinit.go

@@ -115,12 +115,8 @@ func loadImages(cfg *config.Config) error {
 	return nil
 }
 
-func runContainers(cfg *config.Config) error {
+func runContainersFrom(startFrom string, cfg *config.Config, containerConfigs []config.ContainerConfig) error {
-	containerConfigs := cfg.SystemContainers
+	foundStart := false
-	if cfg.Rescue {
-		log.Debug("Running rescue container")
-		containerConfigs = []config.ContainerConfig{*cfg.RescueContainer}
-	}
 
 	for i, containerConfig := range containerConfigs {
 		container := docker.NewContainer(config.DOCKER_SYSTEM_HOST, &containerConfig)
@@ -130,26 +126,50 @@ func runContainers(cfg *config.Config) error {
 			continue
 		}
 
-		if containerConfig.Id == config.CONSOLE_CONTAINER {
+		//if containerConfig.Id == config.CONSOLE_CONTAINER {
-			if util.IsRunningInTty() {
+		//	if util.IsRunningInTty() {
-				container.Config.Tty = true
+		//		container.Config.Tty = true
-				container.Config.AttachStdin = true
+		//		container.Config.AttachStdin = true
-				container.Config.AttachStdout = true
+		//		container.Config.AttachStdout = true
-				container.Config.AttachStderr = true
+		//		container.Config.AttachStderr = true
+		//	}
+		//}
+
+		if foundStart || startFrom == "" {
+			log.Infof("Running [%d/%d] %s", i+1, len(containerConfigs), containerConfig.Id)
+			container.StartAndWait()
+
+			if container.Err != nil {
+				log.Errorf("Failed to run %v: %v", containerConfig.Id, container.Err)
 			}
-		}
 
-		log.Infof("Running [%d/%d] %s", i+1, len(containerConfigs), containerConfig.Id)
+			if containerConfig.ReloadConfig {
-		container.StartAndWait()
+				log.Info("Reloading configuration")
+				err := cfg.Reload()
+				if err != nil {
+					return err
+				}
 
-		if container.Err != nil {
+				return runContainersFrom(containerConfig.Id, cfg, cfg.SystemContainers)
-			log.Errorf("Failed to run %v: %v", containerConfig.Id, container.Err)
+			}
+		} else if startFrom == containerConfig.Id {
+			foundStart = true
 		}
 	}
 
 	return nil
 }
 
+func runContainers(cfg *config.Config) error {
+	containerConfigs := cfg.SystemContainers
+	if cfg.Rescue {
+		log.Debug("Running rescue container")
+		containerConfigs = []config.ContainerConfig{*cfg.RescueContainer}
+	}
+
+	return runContainersFrom("", cfg, containerConfigs)
+}
+
 func launchConsole(cfg *config.Config) error {
 	if !util.IsRunningInTty() {
 		return nil

config/config.go

@@ -36,6 +36,7 @@ type ContainerConfig struct {
 	Id             string `yaml:"id,omitempty"`
 	Cmd            string `yaml:"run,omitempty"`
 	MigrateVolumes bool   `yaml:"migrate_volumes,omitempty"`
+	ReloadConfig   bool   `yaml:"reload_config,omitempty"`
 }
 
 type Config struct {
@@ -52,6 +53,8 @@ type Config struct {
 	Modules          []string          `yaml:"modules,omitempty"`
 	CloudInit        CloudInit         `yaml:"cloud_init"`
 	SshInfo          SshInfo           `yaml:"ssh"`
+	EnabledAddons    []string          `yaml:"enabledAddons,omitempty"`
+	Addons           map[string]Config `yaml:"addons,omitempty"`
 }
 
 type UserDockerInfo struct {
@@ -75,6 +78,32 @@ type CloudInit struct {
 	Datasources []string `yaml:"datasources"`
 }
 
+func (c *Config) PrivilegedMerge(newConfig Config) (bool, error) {
+	reboot, err := c.Merge(newConfig)
+	if err != nil {
+		return reboot, err
+	}
+
+	toAppend := make([]ContainerConfig, 0, 5)
+
+	for _, newContainer := range newConfig.SystemContainers {
+		found := false
+		for i, existingContainer := range c.SystemContainers {
+			if existingContainer.Id != "" && newContainer.Id == existingContainer.Id {
+				found = true
+				c.SystemContainers[i] = newContainer
+			}
+		}
+		if !found {
+			toAppend = append(toAppend, newContainer)
+		}
+	}
+
+	c.SystemContainers = append(c.SystemContainers, toAppend...)
+
+	return reboot, nil
+}
+
 func (c *Config) Merge(newConfig Config) (bool, error) {
 	//Efficient? Nope, but computers are fast
 	newConfig.ClearReadOnly()
@@ -92,6 +121,9 @@ func (c *Config) Merge(newConfig Config) (bool, error) {
 func (c *Config) ClearReadOnly() {
 	c.SystemContainers = []ContainerConfig{}
 	c.RescueContainer = nil
+	c.Rescue = false
+	c.Debug = false
+	c.Addons = map[string]Config{}
 }
 
 func (c *Config) Dump() (string, error) {
@@ -157,7 +189,14 @@ func (c *Config) merge(values map[string]interface{}) error {
 	if err != nil {
 		return err
 	}
-	return yaml.Unmarshal(override, c)
+	var newConfig Config
+	err = yaml.Unmarshal(override, &newConfig)
+	if err != nil {
+		return nil
+	}
+
+	_, err = c.Merge(newConfig)
+	return err
 }
 
 func (c *Config) readFile() error {
@@ -262,13 +301,18 @@ func (c *Config) Reload() error {
 		c.readFile,
 		c.readCmdline,
 		c.readArgs,
+		c.mergeAddons,
 	)
 }
 
-func (c *Config) GetContainerById(id string) *ContainerConfig {
+func (c *Config) mergeAddons() error {
-	for _, c := range c.SystemContainers {
+	for _, addon := range c.EnabledAddons {
-		if c.Id == id {
+		if newConfig, ok := c.Addons[addon]; ok {
-			return &c
+			log.Debugf("Enabling addon %s", addon)
+			_, err := c.PrivilegedMerge(newConfig)
+			if err != nil {
+				return err
+			}
 		}
 	}
 

config/default.go

@@ -19,15 +19,18 @@ func NewConfig() *Config {
 		},
 		SystemContainers: []ContainerConfig{
 			{
+				Id: "system-volumes",
 				Cmd: "--name=system-volumes " +
 					"--net=none " +
 					"--read-only " +
 					"-v=/var/lib/rancher/conf:/var/lib/rancher/conf " +
 					"-v=/lib/modules:/lib/modules:ro " +
 					"-v=/var/run:/var/run " +
+					"-v=/var/log:/var/log " +
 					"state",
 			},
 			{
+				Id: "command-volumes",
 				Cmd: "--name=command-volumes " +
 					"--net=none " +
 					"--read-only " +
@@ -44,6 +47,7 @@ func NewConfig() *Config {
 					"state",
 			},
 			{
+				Id: "user-volumes",
 				Cmd: "--name=user-volumes " +
 					"--net=none " +
 					"--read-only " +
@@ -52,6 +56,7 @@ func NewConfig() *Config {
 					"state",
 			},
 			{
+				Id: "udev",
 				Cmd: "--name=udev " +
 					"--net=none " +
 					"--privileged " +
@@ -61,13 +66,16 @@ func NewConfig() *Config {
 					"udev",
 			},
 			{
+				Id: "cloud-init",
 				Cmd: "--name=cloud-init " +
 					"--rm " +
 					"--net=host " +
 					"--volumes-from=command-volumes " +
 					"cloudinit",
+				ReloadConfig: true,
 			},
 			{
+				Id: "network",
 				Cmd: "--name=network " +
 					"--cap-add=NET_ADMIN " +
 					"--net=host " +
@@ -75,6 +83,7 @@ func NewConfig() *Config {
 					"network",
 			},
 			{
+				Id: "ntp",
 				Cmd: "--name=ntp " +
 					"--rm " +
 					"-d " +
@@ -83,14 +92,19 @@ func NewConfig() *Config {
 					"ntp",
 			},
 			{
+				Id: "syslog",
 				Cmd: "--name=syslog " +
 					"-d " +
 					"--rm " +
 					"--privileged " +
 					"--net=host " +
+					"--ipc=host " +
+					"--pid=host " +
+					"--volumes-from=system-volumes " +
 					"syslog",
 			},
 			{
+				Id: "userdocker",
 				Cmd: "--name=userdocker " +
 					"-d " +
 					"--rm " +
@@ -106,6 +120,7 @@ func NewConfig() *Config {
 					"userdocker",
 			},
 			{
+				Id: "console",
 				Cmd: "--name=console " +
 					"-d " +
 					"--rm " +
@@ -113,13 +128,37 @@ func NewConfig() *Config {
 					"--volumes-from=command-volumes " +
 					"--volumes-from=user-volumes " +
 					"--volumes-from=system-volumes " +
+					"--restart=always " +
 					"--ipc=host " +
 					"--net=host " +
 					"--pid=host " +
 					"console",
 			},
 		},
+		EnabledAddons: []string{},
+		Addons: map[string]Config{
+			"ubuntu-console": {
+				SystemContainers: []ContainerConfig{
+					{
+						Id: "console",
+						Cmd: "--name=ubuntu-console " +
+							"-d " +
+							"--rm " +
+							"--privileged " +
+							"--volumes-from=command-volumes " +
+							"--volumes-from=user-volumes " +
+							"--volumes-from=system-volumes " +
+							"--restart=always " +
+							"--ipc=host " +
+							"--net=host " +
+							"--pid=host " +
+							"rancher/ubuntuconsole",
+					},
+				},
+			},
+		},
 		RescueContainer: &ContainerConfig{
+			Id: "console",
 			Cmd: "--name=rescue " +
 				"-d " +
 				"--rm " +
@@ -127,6 +166,7 @@ func NewConfig() *Config {
 				"--volumes-from=console-volumes " +
 				"--volumes-from=user-volumes " +
 				"--volumes-from=system-volumes " +
+				"--restart=always " +
 				"--ipc=host " +
 				"--net=host " +
 				"--pid=host " +

docker/container.go

@@ -34,7 +34,7 @@ type Container struct {
 	HostConfig   *runconfig.HostConfig
 	dockerHost   string
 	Container    *dockerClient.Container
-	containerCfg *config.ContainerConfig
+	ContainerCfg *config.ContainerConfig
 }
 
 type ByCreated []dockerClient.APIContainers
@@ -65,7 +65,7 @@ func StartAndWait(dockerHost string, containerCfg *config.ContainerConfig) error
 func NewContainer(dockerHost string, containerCfg *config.ContainerConfig) *Container {
 	c := &Container{
 		dockerHost:   dockerHost,
-		containerCfg: containerCfg,
+		ContainerCfg: containerCfg,
 	}
 	return c.Parse()
 }
@@ -102,7 +102,7 @@ func (c *Container) Lookup() *Container {
 		return c
 	}
 
-	hash, err := getHash(c.containerCfg)
+	hash, err := getHash(c.ContainerCfg)
 	if err != nil {
 		return c.returnErr(err)
 	}
@@ -169,7 +169,7 @@ func (c *Container) Parse() *Container {
 	flDetach := flags.Bool([]string{"d", "-detach"}, false, "")
 	flName := flags.String([]string{"#name", "-name"}, "", "")
 
-	args, err := shlex.Split(c.containerCfg.Cmd)
+	args, err := shlex.Split(c.ContainerCfg.Cmd)
 	if err != nil {
 		return c.returnErr(err)
 	}
@@ -181,8 +181,8 @@ func (c *Container) Parse() *Container {
 	c.detach = *flDetach
 	c.remove = *flRemove
 
-	if c.containerCfg.Id == "" {
+	if c.ContainerCfg.Id == "" {
-		c.containerCfg.Id = c.Name
+		c.ContainerCfg.Id = c.Name
 	}
 
 	return c
@@ -327,13 +327,13 @@ func (c *Container) getCreateOpts(client *dockerClient.Client) (*dockerClient.Cr
 		opts.Config.Labels = make(map[string]string)
 	}
 
-	hash, err := getHash(c.containerCfg)
+	hash, err := getHash(c.ContainerCfg)
 	if err != nil {
 		return nil, err
 	}
 
 	opts.Config.Labels[HASH] = hash
-	opts.Config.Labels[ID] = c.containerCfg.Id
+	opts.Config.Labels[ID] = c.ContainerCfg.Id
 
 	return &opts, nil
 }
@@ -398,7 +398,7 @@ func (c *Container) start(wait bool) *Container {
 			return c.returnErr(err)
 		}
 
-		err := appendVolumesFrom(client, c.containerCfg, opts)
+		err := appendVolumesFrom(client, c.ContainerCfg, opts)
 		if err != nil {
 			return c.returnErr(err)
 		}