Merge pull request #13059 from cdoern/clone

Implement Podman Container Clone

1 files changed, 150 insertions, 0 deletions

diff --git a/pkg/specgen/generate/container.go b/pkg/specgen/generate/container.go
index a4d862a60..64669f34d 100644
--- a/pkg/specgen/generate/container.go
+++ b/pkg/specgen/generate/container.go
@@ -2,6 +2,7 @@ package generate
 
 import (
 	"context"
+	"encoding/json"
 	"os"
 	"strings"
 	"time"
@@ -335,3 +336,152 @@ func FinishThrottleDevices(s *specgen.SpecGenerator) error {
 	}
 	return nil
 }
+
+// ConfigToSpec takes a completed container config and converts it back into a specgenerator for purposes of cloning an exisiting container
+func ConfigToSpec(rt *libpod.Runtime, specg *specgen.SpecGenerator, contaierID string) (*libpod.Container, error) {
+	c, err := rt.LookupContainer(contaierID)
+	if err != nil {
+		return nil, err
+	}
+	conf := c.Config()
+
+	tmpSystemd := conf.Systemd
+	tmpMounts := conf.Mounts
+
+	conf.Systemd = nil
+	conf.Mounts = []string{}
+
+	specg.Pod = conf.Pod
+
+	matching, err := json.Marshal(conf)
+	if err != nil {
+		return nil, err
+	}
+
+	err = json.Unmarshal(matching, specg)
+	if err != nil {
+		return nil, err
+	}
+	conf.Systemd = tmpSystemd
+	conf.Mounts = tmpMounts
+
+	if conf.Spec != nil && conf.Spec.Linux != nil && conf.Spec.Linux.Resources != nil {
+		if specg.ResourceLimits == nil {
+			specg.ResourceLimits = conf.Spec.Linux.Resources
+		}
+	}
+
+	nameSpaces := []string{"pid", "net", "cgroup", "ipc", "uts", "user"}
+	containers := []string{conf.PIDNsCtr, conf.NetNsCtr, conf.CgroupNsCtr, conf.IPCNsCtr, conf.UTSNsCtr, conf.UserNsCtr}
+	place := []*specgen.Namespace{&specg.PidNS, &specg.NetNS, &specg.CgroupNS, &specg.IpcNS, &specg.UtsNS, &specg.UserNS}
+	for i, ns := range containers {
+		if len(ns) > 0 {
+			ns := specgen.Namespace{NSMode: specgen.FromContainer, Value: ns}
+			place[i] = &ns
+		} else {
+			switch nameSpaces[i] {
+			case "pid":
+				specg.PidNS = specgen.Namespace{NSMode: specgen.Default} //default
+			case "net":
+				switch {
+				case conf.NetMode.IsBridge():
+					toExpose := make(map[uint16]string, len(conf.ExposedPorts))
+					for _, expose := range []map[uint16][]string{conf.ExposedPorts} {
+						for port, proto := range expose {
+							toExpose[port] = strings.Join(proto, ",")
+						}
+					}
+					specg.Expose = toExpose
+					specg.PortMappings = conf.PortMappings
+					specg.NetNS = specgen.Namespace{NSMode: specgen.Bridge}
+				case conf.NetMode.IsSlirp4netns():
+					toExpose := make(map[uint16]string, len(conf.ExposedPorts))
+					for _, expose := range []map[uint16][]string{conf.ExposedPorts} {
+						for port, proto := range expose {
+							toExpose[port] = strings.Join(proto, ",")
+						}
+					}
+					specg.Expose = toExpose
+					specg.PortMappings = conf.PortMappings
+					netMode := strings.Split(string(conf.NetMode), ":")
+					var val string
+					if len(netMode) > 1 {
+						val = netMode[1]
+					}
+					specg.NetNS = specgen.Namespace{NSMode: specgen.Slirp, Value: val}
+				case conf.NetMode.IsPrivate():
+					specg.NetNS = specgen.Namespace{NSMode: specgen.Private}
+				case conf.NetMode.IsDefault():
+					specg.NetNS = specgen.Namespace{NSMode: specgen.Default}
+				case conf.NetMode.IsUserDefined():
+					specg.NetNS = specgen.Namespace{NSMode: specgen.Path, Value: strings.Split(string(conf.NetMode), ":")[1]}
+				case conf.NetMode.IsContainer():
+					specg.NetNS = specgen.Namespace{NSMode: specgen.FromContainer, Value: strings.Split(string(conf.NetMode), ":")[1]}
+				case conf.NetMode.IsPod():
+					specg.NetNS = specgen.Namespace{NSMode: specgen.FromPod, Value: strings.Split(string(conf.NetMode), ":")[1]}
+				}
+			case "cgroup":
+				specg.CgroupNS = specgen.Namespace{NSMode: specgen.Default} //default
+			case "ipc":
+				if conf.ShmDir == "/dev/shm" {
+					specg.IpcNS = specgen.Namespace{NSMode: specgen.Host}
+				} else {
+					specg.IpcNS = specgen.Namespace{NSMode: specgen.Default} //default
+				}
+			case "uts":
+				specg.UtsNS = specgen.Namespace{NSMode: specgen.Default} //default
+			case "user":
+				if conf.AddCurrentUserPasswdEntry {
+					specg.UserNS = specgen.Namespace{NSMode: specgen.KeepID}
+				} else {
+					specg.UserNS = specgen.Namespace{NSMode: specgen.Default} //default
+				}
+			}
+		}
+	}
+
+	specg.IDMappings = &conf.IDMappings
+	specg.ContainerCreateCommand = conf.CreateCommand
+	if len(specg.Rootfs) == 0 {
+		specg.Rootfs = conf.Rootfs
+	}
+	if len(specg.Image) == 0 {
+		specg.Image = conf.RootfsImageID
+	}
+	var named []*specgen.NamedVolume
+	if len(conf.NamedVolumes) != 0 {
+		for _, v := range conf.NamedVolumes {
+			named = append(named, &specgen.NamedVolume{
+				Name:    v.Name,
+				Dest:    v.Dest,
+				Options: v.Options,
+			})
+		}
+	}
+	specg.Volumes = named
+	var image []*specgen.ImageVolume
+	if len(conf.ImageVolumes) != 0 {
+		for _, v := range conf.ImageVolumes {
+			image = append(image, &specgen.ImageVolume{
+				Source:      v.Source,
+				Destination: v.Dest,
+				ReadWrite:   v.ReadWrite,
+			})
+		}
+	}
+	specg.ImageVolumes = image
+	var overlay []*specgen.OverlayVolume
+	if len(conf.OverlayVolumes) != 0 {
+		for _, v := range conf.OverlayVolumes {
+			overlay = append(overlay, &specgen.OverlayVolume{
+				Source:      v.Source,
+				Destination: v.Dest,
+				Options:     v.Options,
+			})
+		}
+	}
+	specg.OverlayVolumes = overlay
+	specg.Mounts = conf.Spec.Mounts
+	specg.HostDeviceList = conf.DeviceHostSrc
+	return c, nil
+}