diff options
Diffstat (limited to 'pkg/systemd/generate/pods.go')
-rw-r--r-- | pkg/systemd/generate/pods.go | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/pkg/systemd/generate/pods.go b/pkg/systemd/generate/pods.go new file mode 100644 index 000000000..16f324f78 --- /dev/null +++ b/pkg/systemd/generate/pods.go @@ -0,0 +1,130 @@ +package generate + +import ( + "fmt" + "strings" + + "github.com/containers/libpod/libpod" + "github.com/containers/libpod/pkg/domain/entities" + "github.com/pkg/errors" +) + +// PodUnits generates systemd units for the specified pod and its containers. +// Based on the options, the return value might be the content of all units or +// the files they been written to. +func PodUnits(pod *libpod.Pod, options entities.GenerateSystemdOptions) (string, error) { + if options.New { + return "", errors.New("--new is not supported for pods") + } + + // Error out if the pod has no infra container, which we require to be the + // main service. + if !pod.HasInfraContainer() { + return "", fmt.Errorf("error generating systemd unit files: Pod %q has no infra container", pod.Name()) + } + + podInfo, err := generatePodInfo(pod, options) + if err != nil { + return "", err + } + + infraID, err := pod.InfraContainerID() + if err != nil { + return "", err + } + + // Compute the container-dependency graph for the Pod. + containers, err := pod.AllContainers() + if err != nil { + return "", err + } + if len(containers) == 0 { + return "", fmt.Errorf("error generating systemd unit files: Pod %q has no containers", pod.Name()) + } + graph, err := libpod.BuildContainerGraph(containers) + if err != nil { + return "", err + } + + // Traverse the dependency graph and create systemdgen.containerInfo's for + // each container. + containerInfos := []*containerInfo{podInfo} + for ctr, dependencies := range graph.DependencyMap() { + // Skip the infra container as we already generated it. + if ctr.ID() == infraID { + continue + } + ctrInfo, err := generateContainerInfo(ctr, options) + if err != nil { + return "", err + } + // Now add the container's dependencies and at the container as a + // required service of the infra container. + for _, dep := range dependencies { + if dep.ID() == infraID { + ctrInfo.BoundToServices = append(ctrInfo.BoundToServices, podInfo.ServiceName) + } else { + _, serviceName := containerServiceName(dep, options) + ctrInfo.BoundToServices = append(ctrInfo.BoundToServices, serviceName) + } + } + podInfo.RequiredServices = append(podInfo.RequiredServices, ctrInfo.ServiceName) + containerInfos = append(containerInfos, ctrInfo) + } + + // Now generate the systemd service for all containers. + builder := strings.Builder{} + for i, info := range containerInfos { + if i > 0 { + builder.WriteByte('\n') + } + out, err := createContainerSystemdUnit(info, options) + if err != nil { + return "", err + } + builder.WriteString(out) + } + + return builder.String(), nil +} + +func generatePodInfo(pod *libpod.Pod, options entities.GenerateSystemdOptions) (*containerInfo, error) { + // Generate a systemdgen.containerInfo for the infra container. This + // containerInfo acts as the main service of the pod. + infraCtr, err := pod.InfraContainer() + if err != nil { + return nil, errors.Wrap(err, "could not find infra container") + } + + timeout := infraCtr.StopTimeout() + if options.StopTimeout != nil { + timeout = *options.StopTimeout + } + + config := infraCtr.Config() + conmonPidFile := config.ConmonPidFile + if conmonPidFile == "" { + return nil, errors.Errorf("conmon PID file path is empty, try to recreate the container with --conmon-pidfile flag") + } + + createCommand := []string{} + + nameOrID := pod.ID() + ctrNameOrID := infraCtr.ID() + if options.Name { + nameOrID = pod.Name() + ctrNameOrID = infraCtr.Name() + } + serviceName := fmt.Sprintf("%s%s%s", options.PodPrefix, options.Separator, nameOrID) + + info := containerInfo{ + ServiceName: serviceName, + ContainerNameOrID: ctrNameOrID, + RestartPolicy: options.RestartPolicy, + PIDFile: conmonPidFile, + StopTimeout: timeout, + GenerateTimestamp: true, + CreateCommand: createCommand, + } + return &info, nil +} |