podmanV2: implement logs

Implement the `podman {container} logs` for the v2 client. The remote
client does not yet support it.  There's some more work needed for the
rest api; some options are missing (e.g., printing names) while others
are broken (e.g., the until http parameter).

The remote parts will be tackled in a future change.

Signed-off-by: Valentin Rothberg <rothberg@redhat.com>

1 files changed, 108 insertions, 0 deletions

diff --git a/cmd/podmanV2/containers/logs.go b/cmd/podmanV2/containers/logs.go
new file mode 100644
index 000000000..d1a179495
--- /dev/null
+++ b/cmd/podmanV2/containers/logs.go
@@ -0,0 +1,108 @@
+package containers
+
+import (
+	"os"
+
+	"github.com/containers/libpod/cmd/podmanV2/registry"
+	"github.com/containers/libpod/pkg/domain/entities"
+	"github.com/containers/libpod/pkg/util"
+	"github.com/pkg/errors"
+	"github.com/spf13/cobra"
+	"github.com/spf13/pflag"
+)
+
+// logsOptionsWrapper wraps entities.LogsOptions and prevents leaking
+// CLI-only fields into the API types.
+type logsOptionsWrapper struct {
+	entities.ContainerLogsOptions
+
+	SinceRaw string
+}
+
+var (
+	logsOptions     logsOptionsWrapper
+	logsDescription = `Retrieves logs for one or more containers.
+
+  This does not guarantee execution order when combined with podman run (i.e., your run may not have generated any logs at the time you execute podman logs).
+`
+	logsCommand = &cobra.Command{
+		Use:     "logs [flags] CONTAINER [CONTAINER...]",
+		Short:   "Fetch the logs of one or more container",
+		Long:    logsDescription,
+		RunE:    logs,
+		PreRunE: preRunE,
+		Example: `podman logs ctrID
+  podman logs --names ctrID1 ctrID2
+  podman logs --tail 2 mywebserver
+  podman logs --follow=true --since 10m ctrID
+  podman logs mywebserver mydbserver`,
+	}
+
+	containerLogsCommand = &cobra.Command{
+		Use:     logsCommand.Use,
+		Short:   logsCommand.Short,
+		Long:    logsCommand.Long,
+		PreRunE: logsCommand.PreRunE,
+		RunE:    logsCommand.RunE,
+		Example: `podman container logs ctrID
+		podman container logs --names ctrID1 ctrID2
+		podman container logs --tail 2 mywebserver
+		podman container logs --follow=true --since 10m ctrID
+		podman container logs mywebserver mydbserver`,
+	}
+)
+
+func init() {
+	// logs
+	registry.Commands = append(registry.Commands, registry.CliCommand{
+		Mode:    []entities.EngineMode{entities.ABIMode},
+		Command: logsCommand,
+	})
+
+	logsCommand.SetHelpTemplate(registry.HelpTemplate())
+	logsCommand.SetUsageTemplate(registry.UsageTemplate())
+
+	flags := logsCommand.Flags()
+	logsFlags(flags)
+
+	// container logs
+	registry.Commands = append(registry.Commands, registry.CliCommand{
+		Mode:    []entities.EngineMode{entities.ABIMode},
+		Command: containerLogsCommand,
+		Parent:  containerCmd,
+	})
+
+	containerLogsFlags := containerLogsCommand.Flags()
+	logsFlags(containerLogsFlags)
+}
+
+func logsFlags(flags *pflag.FlagSet) {
+	flags.BoolVar(&logsOptions.Details, "details", false, "Show extra details provided to the logs")
+	flags.BoolVarP(&logsOptions.Follow, "follow", "f", false, "Follow log output.  The default is false")
+	flags.BoolVarP(&logsOptions.Latest, "latest", "l", false, "Act on the latest container podman is aware of")
+	flags.StringVar(&logsOptions.SinceRaw, "since", "", "Show logs since TIMESTAMP")
+	flags.Int64Var(&logsOptions.Tail, "tail", -1, "Output the specified number of LINES at the end of the logs.  Defaults to -1, which prints all lines")
+	flags.BoolVarP(&logsOptions.Timestamps, "timestamps", "t", false, "Output the timestamps in the log")
+	flags.BoolVarP(&logsOptions.Names, "names", "n", false, "Output the container name in the log")
+	flags.SetInterspersed(false)
+	_ = flags.MarkHidden("details")
+}
+
+func logs(cmd *cobra.Command, args []string) error {
+	if len(args) > 0 && logsOptions.Latest {
+		return errors.New("no containers can be specified when using 'latest'")
+	}
+	if !logsOptions.Latest && len(args) < 1 {
+		return errors.New("specify at least one container name or ID to log")
+	}
+	if logsOptions.SinceRaw != "" {
+		// parse time, error out if something is wrong
+		since, err := util.ParseInputTime(logsOptions.SinceRaw)
+		if err != nil {
+			return errors.Wrapf(err, "error parsing --since %q", logsOptions.SinceRaw)
+		}
+		logsOptions.Since = since
+	}
+	logsOptions.Writer = os.Stdout
+	return registry.ContainerEngine().ContainerLogs(registry.GetContext(), args, logsOptions.ContainerLogsOptions)
+}