blob: 5e9d5e51052bd6af665591b0dc5823d711554b45 [file] [log] [blame]
package daemon
import (
flag ""
const (
defaultNetworkMtu = 1500
disableNetworkBridge = "none"
// flatOptions contains configuration keys
// that MUST NOT be parsed as deep structures.
// Use this to differentiate these options
// with others like the ones in CommonTLSOptions.
var flatOptions = map[string]bool{
"cluster-store-opts": true,
"log-opts": true,
// LogConfig represents the default log configuration.
// It includes json tags to deserialize configuration from a file
// using the same names that the flags in the command line uses.
type LogConfig struct {
Type string `json:"log-driver,omitempty"`
Config map[string]string `json:"log-opts,omitempty"`
// CommonTLSOptions defines TLS configuration for the daemon server.
// It includes json tags to deserialize configuration from a file
// using the same names that the flags in the command line uses.
type CommonTLSOptions struct {
CAFile string `json:"tlscacert,omitempty"`
CertFile string `json:"tlscert,omitempty"`
KeyFile string `json:"tlskey,omitempty"`
// CommonConfig defines the configuration of a docker daemon which are
// common across platforms.
// It includes json tags to deserialize configuration from a file
// using the same names that the flags in the command line uses.
type CommonConfig struct {
AuthorizationPlugins []string `json:"authorization-plugins,omitempty"` // AuthorizationPlugins holds list of authorization plugins
AutoRestart bool `json:"-"`
Context map[string][]string `json:"-"`
DisableBridge bool `json:"-"`
DNS []string `json:"dns,omitempty"`
DNSOptions []string `json:"dns-opts,omitempty"`
DNSSearch []string `json:"dns-search,omitempty"`
ExecOptions []string `json:"exec-opts,omitempty"`
ExecRoot string `json:"exec-root,omitempty"`
GraphDriver string `json:"storage-driver,omitempty"`
GraphOptions []string `json:"storage-opts,omitempty"`
Labels []string `json:"labels,omitempty"`
Mtu int `json:"mtu,omitempty"`
Pidfile string `json:"pidfile,omitempty"`
RawLogs bool `json:"raw-logs,omitempty"`
Root string `json:"graph,omitempty"`
SocketGroup string `json:"group,omitempty"`
TrustKeyPath string `json:"-"`
// ClusterStore is the storage backend used for the cluster information. It is used by both
// multihost networking (to store networks and endpoints information) and by the node discovery
// mechanism.
ClusterStore string `json:"cluster-store,omitempty"`
// ClusterOpts is used to pass options to the discovery package for tuning libkv settings, such
// as TLS configuration settings.
ClusterOpts map[string]string `json:"cluster-store-opts,omitempty"`
// ClusterAdvertise is the network endpoint that the Engine advertises for the purpose of node
// discovery. This should be a 'host:port' combination on which that daemon instance is
// reachable by other hosts.
ClusterAdvertise string `json:"cluster-advertise,omitempty"`
Debug bool `json:"debug,omitempty"`
Hosts []string `json:"hosts,omitempty"`
LogLevel string `json:"log-level,omitempty"`
TLS bool `json:"tls,omitempty"`
TLSVerify bool `json:"tlsverify,omitempty"`
// Embedded structs that allow config
// deserialization without the full struct.
bridgeConfig // bridgeConfig holds bridge network specific configuration.
reloadLock sync.Mutex
valuesSet map[string]interface{}
// InstallCommonFlags adds command-line options to the top-level flag parser for
// the current process.
// Subsequent calls to `flag.Parse` will populate config with values parsed
// from the command-line.
func (config *Config) InstallCommonFlags(cmd *flag.FlagSet, usageFn func(string) string) {
config.ServiceOptions.InstallCliFlags(cmd, usageFn)
cmd.Var(opts.NewNamedListOptsRef("storage-opts", &config.GraphOptions, nil), []string{"-storage-opt"}, usageFn("Set storage driver options"))
cmd.Var(opts.NewNamedListOptsRef("authorization-plugins", &config.AuthorizationPlugins, nil), []string{"-authorization-plugin"}, usageFn("List authorization plugins in order from first evaluator to last"))
cmd.Var(opts.NewNamedListOptsRef("exec-opts", &config.ExecOptions, nil), []string{"-exec-opt"}, usageFn("Set runtime execution options"))
cmd.StringVar(&config.Pidfile, []string{"p", "-pidfile"}, defaultPidFile, usageFn("Path to use for daemon PID file"))
cmd.StringVar(&config.Root, []string{"g", "-graph"}, defaultGraph, usageFn("Root of the Docker runtime"))
cmd.StringVar(&config.ExecRoot, []string{"-exec-root"}, defaultExecRoot, usageFn("Root directory for execution state files"))
cmd.BoolVar(&config.AutoRestart, []string{"#r", "#-restart"}, true, usageFn("--restart on the daemon has been deprecated in favor of --restart policies on docker run"))
cmd.StringVar(&config.GraphDriver, []string{"s", "-storage-driver"}, "", usageFn("Storage driver to use"))
cmd.IntVar(&config.Mtu, []string{"#mtu", "-mtu"}, 0, usageFn("Set the containers network MTU"))
cmd.BoolVar(&config.RawLogs, []string{"-raw-logs"}, false, usageFn("Full timestamps without ANSI coloring"))
// FIXME: why the inconsistency between "hosts" and "sockets"?
cmd.Var(opts.NewListOptsRef(&config.DNS, opts.ValidateIPAddress), []string{"#dns", "-dns"}, usageFn("DNS server to use"))
cmd.Var(opts.NewNamedListOptsRef("dns-opts", &config.DNSOptions, nil), []string{"-dns-opt"}, usageFn("DNS options to use"))
cmd.Var(opts.NewListOptsRef(&config.DNSSearch, opts.ValidateDNSSearch), []string{"-dns-search"}, usageFn("DNS search domains to use"))
cmd.Var(opts.NewNamedListOptsRef("labels", &config.Labels, opts.ValidateLabel), []string{"-label"}, usageFn("Set key=value labels to the daemon"))
cmd.StringVar(&config.LogConfig.Type, []string{"-log-driver"}, "json-file", usageFn("Default driver for container logs"))
cmd.Var(opts.NewNamedMapOpts("log-opts", config.LogConfig.Config, nil), []string{"-log-opt"}, usageFn("Set log driver options"))
cmd.StringVar(&config.ClusterAdvertise, []string{"-cluster-advertise"}, "", usageFn("Address or interface name to advertise"))
cmd.StringVar(&config.ClusterStore, []string{"-cluster-store"}, "", usageFn("Set the cluster store"))
cmd.Var(opts.NewNamedMapOpts("cluster-store-opts", config.ClusterOpts, nil), []string{"-cluster-store-opt"}, usageFn("Set cluster store options"))
// IsValueSet returns true if a configuration value
// was explicitly set in the configuration file.
func (config *Config) IsValueSet(name string) bool {
if config.valuesSet == nil {
return false
_, ok := config.valuesSet[name]
return ok
func parseClusterAdvertiseSettings(clusterStore, clusterAdvertise string) (string, error) {
if clusterAdvertise == "" {
return "", errDiscoveryDisabled
if clusterStore == "" {
return "", fmt.Errorf("invalid cluster configuration. --cluster-advertise must be accompanied by --cluster-store configuration")
advertise, err := discovery.ParseAdvertise(clusterAdvertise)
if err != nil {
return "", fmt.Errorf("discovery advertise parsing failed (%v)", err)
return advertise, nil
// ReloadConfiguration reads the configuration in the host and reloads the daemon and server.
func ReloadConfiguration(configFile string, flags *flag.FlagSet, reload func(*Config)) error {
logrus.Infof("Got signal to reload configuration, reloading from: %s", configFile)
newConfig, err := getConflictFreeConfiguration(configFile, flags)
if err != nil {
return err
if err := validateConfiguration(newConfig); err != nil {
return fmt.Errorf("file configuration validation failed (%v)", err)
return nil
// boolValue is an interface that boolean value flags implement
// to tell the command line how to make -name equivalent to -name=true.
type boolValue interface {
IsBoolFlag() bool
// MergeDaemonConfigurations reads a configuration file,
// loads the file configuration in an isolated structure,
// and merges the configuration provided from flags on top
// if there are no conflicts.
func MergeDaemonConfigurations(flagsConfig *Config, flags *flag.FlagSet, configFile string) (*Config, error) {
fileConfig, err := getConflictFreeConfiguration(configFile, flags)
if err != nil {
return nil, err
if err := validateConfiguration(fileConfig); err != nil {
return nil, fmt.Errorf("file configuration validation failed (%v)", err)
// merge flags configuration on top of the file configuration
if err := mergo.Merge(fileConfig, flagsConfig); err != nil {
return nil, err
return fileConfig, nil
// getConflictFreeConfiguration loads the configuration from a JSON file.
// It compares that configuration with the one provided by the flags,
// and returns an error if there are conflicts.
func getConflictFreeConfiguration(configFile string, flags *flag.FlagSet) (*Config, error) {
b, err := ioutil.ReadFile(configFile)
if err != nil {
return nil, err
var config Config
var reader io.Reader
if flags != nil {
var jsonConfig map[string]interface{}
reader = bytes.NewReader(b)
if err := json.NewDecoder(reader).Decode(&jsonConfig); err != nil {
return nil, err
configSet := configValuesSet(jsonConfig)
if err := findConfigurationConflicts(configSet, flags); err != nil {
return nil, err
// Override flag values to make sure the values set in the config file with nullable values, like `false`,
// are not overriden by default truthy values from the flags that were not explicitly set.
// See for an example.
// TODO: Rewrite configuration logic to avoid same issue with other nullable values, like numbers.
namedOptions := make(map[string]interface{})
for key, value := range configSet {
f := flags.Lookup("-" + key)
if f == nil { // ignore named flags that don't match
namedOptions[key] = value
if _, ok := f.Value.(boolValue); ok {
f.Value.Set(fmt.Sprintf("%v", value))
if len(namedOptions) > 0 {
// set also default for mergeVal flags that are boolValue at the same time.
flags.VisitAll(func(f *flag.Flag) {
if opt, named := f.Value.(opts.NamedOption); named {
v, set := namedOptions[opt.Name()]
_, boolean := f.Value.(boolValue)
if set && boolean {
f.Value.Set(fmt.Sprintf("%v", v))
config.valuesSet = configSet
reader = bytes.NewReader(b)
err = json.NewDecoder(reader).Decode(&config)
return &config, err
// configValuesSet returns the configuration values explicitly set in the file.
func configValuesSet(config map[string]interface{}) map[string]interface{} {
flatten := make(map[string]interface{})
for k, v := range config {
if m, isMap := v.(map[string]interface{}); isMap && !flatOptions[k] {
for km, vm := range m {
flatten[km] = vm
flatten[k] = v
return flatten
// findConfigurationConflicts iterates over the provided flags searching for
// duplicated configurations and unknown keys. It returns an error with all the conflicts if
// it finds any.
func findConfigurationConflicts(config map[string]interface{}, flags *flag.FlagSet) error {
// 1. Search keys from the file that we don't recognize as flags.
unknownKeys := make(map[string]interface{})
for key, value := range config {
flagName := "-" + key
if flag := flags.Lookup(flagName); flag == nil {
unknownKeys[key] = value
// 2. Discard values that implement NamedOption.
// Their configuration name differs from their flag name, like `labels` and `label`.
if len(unknownKeys) > 0 {
unknownNamedConflicts := func(f *flag.Flag) {
if namedOption, ok := f.Value.(opts.NamedOption); ok {
if _, valid := unknownKeys[namedOption.Name()]; valid {
delete(unknownKeys, namedOption.Name())
if len(unknownKeys) > 0 {
var unknown []string
for key := range unknownKeys {
unknown = append(unknown, key)
return fmt.Errorf("the following directives don't match any configuration option: %s", strings.Join(unknown, ", "))
var conflicts []string
printConflict := func(name string, flagValue, fileValue interface{}) string {
return fmt.Sprintf("%s: (from flag: %v, from file: %v)", name, flagValue, fileValue)
// 3. Search keys that are present as a flag and as a file option.
duplicatedConflicts := func(f *flag.Flag) {
// search option name in the json configuration payload if the value is a named option
if namedOption, ok := f.Value.(opts.NamedOption); ok {
if optsValue, ok := config[namedOption.Name()]; ok {
conflicts = append(conflicts, printConflict(namedOption.Name(), f.Value.String(), optsValue))
} else {
// search flag name in the json configuration payload without trailing dashes
for _, name := range f.Names {
name = strings.TrimLeft(name, "-")
if value, ok := config[name]; ok {
conflicts = append(conflicts, printConflict(name, f.Value.String(), value))
if len(conflicts) > 0 {
return fmt.Errorf("the following directives are specified both as a flag and in the configuration file: %s", strings.Join(conflicts, ", "))
return nil
// validateConfiguration validates some specific configs.
// such as config.DNS, config.Labels, config.DNSSearch
func validateConfiguration(config *Config) error {
// validate DNS
for _, dns := range config.DNS {
if _, err := opts.ValidateIPAddress(dns); err != nil {
return err
// validate DNSSearch
for _, dnsSearch := range config.DNSSearch {
if _, err := opts.ValidateDNSSearch(dnsSearch); err != nil {
return err
// validate Labels
for _, label := range config.Labels {
if _, err := opts.ValidateLabel(label); err != nil {
return err
return nil