Merge pull request #366 from rhatdan/transports

Give more useful help when explaining usage

cmd/skopeo/copy.go

@@ -4,8 +4,10 @@ import (
 	"errors"
 	"fmt"
 	"os"
+	"strings"
 
 	"github.com/containers/image/copy"
+	"github.com/containers/image/transports"
 	"github.com/containers/image/transports/alltransports"
 	"github.com/containers/image/types"
 	"github.com/urfave/cli"
@@ -63,8 +65,17 @@ func copyHandler(context *cli.Context) error {
 }
 
 var copyCmd = cli.Command{
-	Name:      "copy",
+	Name:  "copy",
-	Usage:     "Copy an image from one location to another",
+	Usage: "Copy an IMAGE-NAME from one location to another",
+	Description: fmt.Sprintf(`
+
+	Container "IMAGE-NAME" uses a "transport":"details" format.
+
+	Supported transports:
+	%s
+
+	See skopeo(1) section "IMAGE NAMES" for the expected format
+	`, strings.Join(transports.ListNames(), ", ")),
 	ArgsUsage: "SOURCE-IMAGE DESTINATION-IMAGE",
 	Action:    copyHandler,
 	// FIXME: Do we need to namespace the GPG aspect?

cmd/skopeo/delete.go

@@ -3,7 +3,9 @@ package main
 import (
 	"errors"
 	"fmt"
+	"strings"
 
+	"github.com/containers/image/transports"
 	"github.com/containers/image/transports/alltransports"
 	"github.com/urfave/cli"
 )
@@ -29,8 +31,16 @@ func deleteHandler(context *cli.Context) error {
 }
 
 var deleteCmd = cli.Command{
-	Name:      "delete",
+	Name:  "delete",
-	Usage:     "Delete image IMAGE-NAME",
+	Usage: "Delete image IMAGE-NAME",
+	Description: fmt.Sprintf(`
+	Delete an "IMAGE_NAME" from a transport
+
+	Supported transports:
+	%s
+
+	See skopeo(1) section "IMAGE NAMES" for the expected format
+	`, strings.Join(transports.ListNames(), ", ")),
 	ArgsUsage: "IMAGE-NAME",
 	Action:    deleteHandler,
 	Flags: []cli.Flag{

cmd/skopeo/inspect.go

@@ -9,6 +9,7 @@ import (
 	"github.com/Sirupsen/logrus"
 	"github.com/containers/image/docker"
 	"github.com/containers/image/manifest"
+	"github.com/containers/image/transports"
 	"github.com/opencontainers/go-digest"
 	"github.com/pkg/errors"
 	"github.com/urfave/cli"
@@ -29,8 +30,16 @@ type inspectOutput struct {
 }
 
 var inspectCmd = cli.Command{
-	Name:      "inspect",
+	Name:  "inspect",
-	Usage:     "Inspect image IMAGE-NAME",
+	Usage: "Inspect image IMAGE-NAME",
+	Description: fmt.Sprintf(`
+	Return low-level information about "IMAGE-NAME" in a registry/transport
+
+	Supported transports:
+	%s
+
+	See skopeo(1) section "IMAGE NAMES" for the expected format
+	`, strings.Join(transports.ListNames(), ", ")),
 	ArgsUsage: "IMAGE-NAME",
 	Flags: []cli.Flag{
 		cli.StringFlag{

docs/skopeo.1.md

@@ -12,26 +12,29 @@ It also allows you to copy container images between various registries, possibly
 ## IMAGE NAMES
 Most commands refer to container images, using a _transport_`:`_details_ format. The following formats are supported:
 
-  **atomic:**_namespace_**/**_stream_**:**_tag_
+  **atomic:**_hostname_**/**_namespace_**/**_stream_**:**_tag_
-  An image in the current project of the current default Atomic
+  An image served by an OpenShift(Atomic) Registry server. The current OpenShift project and OpenShift Registry instance are by default read from `$HOME/.kube/config`, which is set e.g. using `(oc login)`.
-  Registry. The current project and Atomic Registry instance are by
+
-  default read from `$HOME/.kube/config`, which is set e.g. using
+  **containers-storage://**_docker-reference_
-  `(oc login)`.
+  An image located in a local containers/storage image store.  Location and image store specified in /etc/containers/storage.conf
 
   **dir:**_path_
-  An existing local directory _path_ storing the manifest, layer
+  An existing local directory _path_ storing the manifest, layer tarballs and signatures as individual files. This is a non-standardized format, primarily useful for debugging or noninvasive container inspection.
-  tarballs and signatures as individual files. This is a
-  non-standardized format, primarily useful for debugging or
-  noninvasive container inspection.
 
   **docker://**_docker-reference_
-  An image in a registry implementing the "Docker Registry HTTP API V2".
+  An image in a registry implementing the "Docker Registry HTTP API V2". By default, uses the authorization state in `$HOME/.docker/config.json`, which is set e.g. using `(docker login)`.
-  By default, uses the authorization state in `$HOME/.docker/config.json`,
+
-  which is set e.g. using `(docker login)`.
+  **docker-archive:**_path_[**:**_docker-reference_]
+  An image is stored in the `docker save` formated file.  _docker-reference_ is only used when creating such a file, and it must not contain a digest.
+
+  **docker-daemon:**_docker-reference_
+  An image _docker-reference_ stored in the docker daemon internal storage.  _docker-reference_ must contain either a tag or a digest.  Alternatively, when reading images, the format can also be docker-daemon:algo:digest (an image ID).
 
   **oci:**_path_**:**_tag_
-  An image _tag_ in a directory compliant with "Open Container Image
+  An image _tag_ in a directory compliant with "Open Container Image Layout Specification" at _path_.
-  Layout Specification" at _path_.
+
+  **ostree:**_image_[**@**_/absolute/repo/path_]
+  An image in local OSTree repository.  _/absolute/repo/path_ defaults to _/ostree/repo_.
 
 # OPTIONS