package daemon import ( "encoding/json" "io" "github.com/docker/docker/api/types" "github.com/docker/docker/daemon/execdriver" "github.com/docker/libnetwork/osl" "github.com/opencontainers/runc/libcontainer" ) // ContainerStatsConfig holds information for configuring the runtime // behavior of a daemon.ContainerStats() call. type ContainerStatsConfig struct { Stream bool OutStream io.Writer Stop <-chan bool } // ContainerStats writes information about the container to the stream // given in the config object. func (daemon *Daemon) ContainerStats(container *Container, config *ContainerStatsConfig) error { updates, err := daemon.subscribeToContainerStats(container) if err != nil { return err } if config.Stream { config.OutStream.Write(nil) } var preCPUStats types.CPUStats getStat := func(v interface{}) *types.Stats { update := v.(*execdriver.ResourceStats) // Retrieve the nw statistics from libnetwork and inject them in the Stats if nwStats, err := daemon.getNetworkStats(container); err == nil { update.Stats.Interfaces = nwStats } ss := convertStatsToAPITypes(update.Stats) ss.PreCPUStats = preCPUStats ss.MemoryStats.Limit = uint64(update.MemoryLimit) ss.Read = update.Read ss.CPUStats.SystemUsage = update.SystemUsage preCPUStats = ss.CPUStats return ss } enc := json.NewEncoder(config.OutStream) defer daemon.unsubscribeToContainerStats(container, updates) noStreamFirstFrame := true for { select { case v, ok := <-updates: if !ok { return nil } s := getStat(v) if !config.Stream && noStreamFirstFrame { // prime the cpu stats so they aren't 0 in the final output noStreamFirstFrame = false continue } if err := enc.Encode(s); err != nil { return err } if !config.Stream { return nil } case <-config.Stop: return nil } } } func (daemon *Daemon) getNetworkStats(c *Container) ([]*libcontainer.NetworkInterface, error) { var list []*libcontainer.NetworkInterface sb, err := daemon.netController.SandboxByID(c.NetworkSettings.SandboxID) if err != nil { return list, err } stats, err := sb.Statistics() if err != nil { return list, err } // Convert libnetwork nw stats into libcontainer nw stats for ifName, ifStats := range stats { list = append(list, convertLnNetworkStats(ifName, ifStats)) } return list, nil } func convertLnNetworkStats(name string, stats *osl.InterfaceStatistics) *libcontainer.NetworkInterface { n := &libcontainer.NetworkInterface{Name: name} n.RxBytes = stats.RxBytes n.RxPackets = stats.RxPackets n.RxErrors = stats.RxErrors n.RxDropped = stats.RxDropped n.TxBytes = stats.TxBytes n.TxPackets = stats.TxPackets n.TxErrors = stats.TxErrors n.TxDropped = stats.TxDropped return n }