moby/daemon/stats.go
Sebastiaan van Stijn fdc8cce070 Merge pull request #16742 from runcom/10772-docker-stats-all
Allow docker stats without arguments
2015-11-07 19:41:03 +00:00

124 lines
3 KiB
Go

package daemon
import (
"encoding/json"
"io"
"github.com/docker/docker/api/types"
"github.com/docker/docker/api/types/versions/v1p20"
"github.com/docker/docker/daemon/execdriver"
"github.com/docker/docker/pkg/version"
)
// ContainerStatsConfig holds information for configuring the runtime
// behavior of a daemon.ContainerStats() call.
type ContainerStatsConfig struct {
Stream bool
OutStream io.Writer
Stop <-chan bool
Version version.Version
}
// ContainerStats writes information about the container to the stream
// given in the config object.
func (daemon *Daemon) ContainerStats(prefixOrName string, config *ContainerStatsConfig) error {
container, err := daemon.Get(prefixOrName)
if err != nil {
return err
}
// If the container is not running and requires no stream, return an empty stats.
if !container.IsRunning() && !config.Stream {
return json.NewEncoder(config.OutStream).Encode(&types.Stats{})
}
if config.Stream {
// Write an empty chunk of data.
// This is to ensure that the HTTP status code is sent immediately,
// even if the container has not yet produced any data.
config.OutStream.Write(nil)
}
var preCPUStats types.CPUStats
getStatJSON := func(v interface{}) *types.StatsJSON {
update := v.(*execdriver.ResourceStats)
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)
updates := daemon.subscribeToContainerStats(container)
defer daemon.unsubscribeToContainerStats(container, updates)
noStreamFirstFrame := true
for {
select {
case v, ok := <-updates:
if !ok {
return nil
}
var statsJSON interface{}
statsJSONPost120 := getStatJSON(v)
if config.Version.LessThan("1.21") {
var (
rxBytes uint64
rxPackets uint64
rxErrors uint64
rxDropped uint64
txBytes uint64
txPackets uint64
txErrors uint64
txDropped uint64
)
for _, v := range statsJSONPost120.Networks {
rxBytes += v.RxBytes
rxPackets += v.RxPackets
rxErrors += v.RxErrors
rxDropped += v.RxDropped
txBytes += v.TxBytes
txPackets += v.TxPackets
txErrors += v.TxErrors
txDropped += v.TxDropped
}
statsJSON = &v1p20.StatsJSON{
Stats: statsJSONPost120.Stats,
Network: types.NetworkStats{
RxBytes: rxBytes,
RxPackets: rxPackets,
RxErrors: rxErrors,
RxDropped: rxDropped,
TxBytes: txBytes,
TxPackets: txPackets,
TxErrors: txErrors,
TxDropped: txDropped,
},
}
} else {
statsJSON = statsJSONPost120
}
if !config.Stream && noStreamFirstFrame {
// prime the cpu stats so they aren't 0 in the final output
noStreamFirstFrame = false
continue
}
if err := enc.Encode(statsJSON); err != nil {
return err
}
if !config.Stream {
return nil
}
case <-config.Stop:
return nil
}
}
}