Initial port of kubectl logs

pkg/kube/pod_logs.go

@@ -0,0 +1,186 @@
+package kube
+
+import (
+	"time"
+	"k8s.io/kubernetes/pkg/kubectl/cmd"
+	"io"
+	"math"
+	"errors"
+	"k8s.io/kubernetes/pkg/api"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	cmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"
+	"k8s.io/kubernetes/pkg/kubectl/resource"
+	"k8s.io/kubernetes/pkg/api/validation"
+	"k8s.io/apimachinery/pkg/runtime"
+)
+
+// Mimics kubectl logs functionality
+
+var (
+	selectorTail int64 = 10
+)
+
+// All options that can be passed to kubectl logs
+type LogOptions struct {
+	// Specify if the logs should be streamed.
+	Follow bool
+	// Include timestamps on each line in the log output
+	Timestamps bool
+	// Maximum bytes of logs to return. Defaults to no limit.
+	LimitBytes int64
+	// If true, print the logs for the previous instance of the container in a pod if it exists.
+	Previous bool
+	// Lines of recent log file to display. Defaults to -1 with no selector, showing all log lines otherwise 10, if a selector is provided.
+	Tail int64
+	// Only return logs after a specific date (RFC3339). Defaults to all logs. Only one of since-time / since may be used.
+	SinceTime time.Time
+	// Only return logs newer than a relative duration like 5s, 2m, or 3h. Defaults to all logs. Only one of since-time / since may be used.
+	Since time.Duration
+	// Print the logs of this container
+	Container string
+	// Selector (label query) to filter on.
+	Selector string
+	// Namespace to query for logs
+	Namespace string
+	// Resource to query for logs
+	Resource string
+}
+
+func NewOptions() *LogOptions {
+	return &LogOptions{
+		Follow: false,
+		Timestamps: false,
+		LimitBytes: 0,
+		Previous: false,
+		Tail: -1,
+		SinceTime: nil,
+		Since: nil,
+		Container: "",
+		Selector: "",
+		Namespace: "",
+		Resource: "",
+	}
+}
+
+func (o *LogOptions) ExecuteLogRequest(out io.Writer) {
+	f := cmdutil.NewFactory(nil)
+	Complete(o, f, out)
+}
+
+func Complete(opts *LogOptions, f cmdutil.Factory, out io.Writer) (*cmd.LogsOptions, error) {
+	o := &cmd.LogsOptions{}
+	containerName := opts.Container
+	selector := opts.Selector
+	if len(opts.Resource) != 0 && len(opts.Selector) != 0 {
+		return nil, errors.New("Specify either a selector or a resource, not both")
+	}
+	o.Namespace = opts.Namespace
+	if o.Namespace == "" {
+		return nil, errors.New("Namespace is required")
+	}
+
+	logOptions := &api.PodLogOptions{
+		Container:  containerName,
+		Follow:     opts.Follow,
+		Previous:   opts.Previous,
+		Timestamps: opts.Timestamps,
+	}
+	if opts.SinceTime {
+		t := metav1.NewTime(opts.SinceTime)
+		logOptions.SinceTime = &t
+	}
+	if opts.LimitBytes != 0 {
+		logOptions.LimitBytes = &opts.LimitBytes
+	}
+	if opts.Tail != -1 {
+		logOptions.TailLines = &opts.Tail
+	}
+	if opts.Since {
+		// round up to the nearest second
+		sec := int64(math.Ceil(opts.Since.Seconds()))
+		logOptions.SinceSeconds = &sec
+	}
+	o.Options = logOptions
+	o.LogsForObject = f.LogsForObject
+	o.ClientMapper = resource.ClientMapperFunc(f.ClientForMapping)
+	o.Out = out
+
+	if len(selector) != 0 {
+		if logOptions.Follow {
+			return nil, errors.New("only one of follow (-f) or selector (-l) is allowed")
+		}
+		if len(logOptions.Container) != 0 {
+			return nil, errors.New( "a container cannot be specified when using a selector (-l)")
+		}
+		if logOptions.TailLines == nil {
+			logOptions.TailLines = &selectorTail
+		}
+	}
+
+	mapper, typer := f.Object()
+	decoder := f.Decoder(true)
+	if o.Object == nil {
+		builder := resource.NewBuilder(mapper, typer, o.ClientMapper, decoder).
+			NamespaceParam(o.Namespace).DefaultNamespace().
+			SingleResourceType()
+		if o.ResourceArg != "" {
+			builder.ResourceNames("pods", o.ResourceArg)
+		}
+		if selector != "" {
+			builder.ResourceTypes("pods").SelectorParam(selector)
+		}
+		infos, err := builder.Do().Infos()
+		if err != nil {
+			return nil, err
+		}
+		if selector == "" && len(infos) != 1 {
+			return nil, errors.New("expected a resource")
+		}
+		o.Object = infos[0].Object
+	}
+
+	return o, nil
+}
+
+func Validate(o *cmd.LogsOptions) error {
+	logsOptions, ok := o.Options.(*api.PodLogOptions)
+	if !ok {
+		return errors.New("unexpected logs options object")
+	}
+	if errs := validation.ValidatePodLogOptions(logsOptions); len(errs) > 0 {
+		return errs.ToAggregate()
+	}
+
+	return nil
+}
+
+// RunLogs retrieves a pod log
+func RunLogs(o *cmd.LogsOptions) error {
+	switch t := o.Object.(type) {
+	case *api.PodList:
+		for _, p := range t.Items {
+			if err := getLogs(o, &p); err != nil {
+				return err
+			}
+		}
+		return nil
+	default:
+		return getLogs(o, o.Object)
+	}
+}
+
+func getLogs(o *cmd.LogsOptions, obj runtime.Object) error {
+	req, err := o.LogsForObject(obj, o.Options)
+	if err != nil {
+		return err
+	}
+
+	readCloser, err := req.Stream()
+	if err != nil {
+		return err
+	}
+	defer readCloser.Close()
+
+	_, err = io.Copy(o.Out, readCloser)
+	return err
+}