moby/daemon/stats.go
Brian Goff ae4ee974e8 Move stream flushes to backend
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
2016-02-09 14:25:02 -05:00

125 lines
3 KiB
Go

package daemon
import (
"encoding/json"
"errors"
"runtime"
"github.com/docker/docker/api/types/backend"
"github.com/docker/docker/daemon/execdriver"
"github.com/docker/docker/pkg/ioutils"
"github.com/docker/docker/pkg/version"
"github.com/docker/engine-api/types"
"github.com/docker/engine-api/types/versions/v1p20"
)
// ContainerStats writes information about the container to the stream
// given in the config object.
func (daemon *Daemon) ContainerStats(prefixOrName string, config *backend.ContainerStatsConfig) error {
if runtime.GOOS == "windows" {
return errors.New("Windows does not support stats")
}
// Remote API version (used for backwards compatibility)
apiVersion := version.Version(config.Version)
container, err := daemon.GetContainer(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{})
}
outStream := config.OutStream
if config.Stream {
wf := ioutils.NewWriteFlusher(outStream)
defer wf.Close()
wf.Flush()
outStream = wf
}
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(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 apiVersion.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
}
}
}