package runconfig import ( "encoding/json" "io" "strings" "github.com/docker/docker/nat" ) // Entrypoint encapsulates the container entrypoint. // It might be represented as a string or an array of strings. // We need to override the json decoder to accept both options. // The JSON decoder will fail if the api sends an string and // we try to decode it into an array of string. type Entrypoint struct { parts []string } func (e *Entrypoint) MarshalJSON() ([]byte, error) { if e == nil { return []byte{}, nil } return json.Marshal(e.Slice()) } // UnmarshalJSON decoded the entrypoint whether it's a string or an array of strings. func (e *Entrypoint) UnmarshalJSON(b []byte) error { if len(b) == 0 { return nil } p := make([]string, 0, 1) if err := json.Unmarshal(b, &p); err != nil { p = append(p, string(b)) } e.parts = p return nil } func (e *Entrypoint) Len() int { if e == nil { return 0 } return len(e.parts) } func (e *Entrypoint) Slice() []string { if e == nil { return nil } return e.parts } func NewEntrypoint(parts ...string) *Entrypoint { return &Entrypoint{parts} } type Command struct { parts []string } func (e *Command) ToString() string { return strings.Join(e.parts, " ") } func (e *Command) MarshalJSON() ([]byte, error) { if e == nil { return []byte{}, nil } return json.Marshal(e.Slice()) } // UnmarshalJSON decoded the entrypoint whether it's a string or an array of strings. func (e *Command) UnmarshalJSON(b []byte) error { if len(b) == 0 { return nil } p := make([]string, 0, 1) if err := json.Unmarshal(b, &p); err != nil { p = append(p, string(b)) } e.parts = p return nil } func (e *Command) Len() int { if e == nil { return 0 } return len(e.parts) } func (e *Command) Slice() []string { if e == nil { return nil } return e.parts } func NewCommand(parts ...string) *Command { return &Command{parts} } // Note: the Config structure should hold only portable information about the container. // Here, "portable" means "independent from the host we are running on". // Non-portable information *should* appear in HostConfig. type Config struct { Hostname string Domainname string User string AttachStdin bool AttachStdout bool AttachStderr bool ExposedPorts map[nat.Port]struct{} PublishService string Tty bool // Attach standard streams to a tty, including stdin if it is not closed. OpenStdin bool // Open stdin StdinOnce bool // If true, close stdin after the 1 attached client disconnects. Env []string Cmd *Command Image string // Name of the image as it was passed by the operator (eg. could be symbolic) Volumes map[string]struct{} VolumeDriver string WorkingDir string Entrypoint *Entrypoint NetworkDisabled bool MacAddress string OnBuild []string Labels map[string]string } type ContainerConfigWrapper struct { *Config InnerHostConfig *HostConfig `json:"HostConfig,omitempty"` Cpuset string `json:",omitempty"` // Deprecated. Exported for backwards compatibility. *HostConfig // Deprecated. Exported to read attrubutes from json that are not in the inner host config structure. } func (w *ContainerConfigWrapper) GetHostConfig() *HostConfig { hc := w.HostConfig if hc == nil && w.InnerHostConfig != nil { hc = w.InnerHostConfig } else if w.InnerHostConfig != nil { if hc.Memory != 0 && w.InnerHostConfig.Memory == 0 { w.InnerHostConfig.Memory = hc.Memory } if hc.MemorySwap != 0 && w.InnerHostConfig.MemorySwap == 0 { w.InnerHostConfig.MemorySwap = hc.MemorySwap } if hc.CpuShares != 0 && w.InnerHostConfig.CpuShares == 0 { w.InnerHostConfig.CpuShares = hc.CpuShares } hc = w.InnerHostConfig } if hc != nil && w.Cpuset != "" && hc.CpusetCpus == "" { hc.CpusetCpus = w.Cpuset } return hc } // DecodeContainerConfig decodes a json encoded config into a ContainerConfigWrapper // struct and returns both a Config and an HostConfig struct // Be aware this function is not checking whether the resulted structs are nil, // it's your business to do so func DecodeContainerConfig(src io.Reader) (*Config, *HostConfig, error) { decoder := json.NewDecoder(src) var w ContainerConfigWrapper if err := decoder.Decode(&w); err != nil { return nil, nil, err } return w.Config, w.GetHostConfig(), nil }