Initial commit

vendor/github.com/hyperhq/hypercli/daemon/stats.go

@@ -0,0 +1,130 @@
+package daemon
+
+import (
+	"encoding/json"
+	"errors"
+	"io"
+	"runtime"
+
+	"github.com/hyperhq/hypercli/daemon/execdriver"
+	"github.com/hyperhq/hypercli/pkg/version"
+	"github.com/docker/engine-api/types"
+	"github.com/docker/engine-api/types/versions/v1p20"
+)
+
+// 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 {
+	if runtime.GOOS == "windows" {
+		return errors.New("Windows does not support stats")
+	}
+
+	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{})
+	}
+
+	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
+		}
+	}
+}