Add support for external container

External containers are containers created outside of Podman.
For example Buildah and CRI-O Containers.

$ buildah from alpine
alpine-working-container
$ buildah run alpine-working-container touch /test
$ podman container exists --external alpine-working-container

$ podman container diff alpine-working-container
C /etc
A /test

Added --external flag to refer to external containers, rather then --storage.

Added --external for podman container exists and modified podman ps to use
--external rather then --storage.  It was felt that --storage would confuse
the user into thinking about changing the storage driver or options.

--storage is still supported through the use of aliases.

Finally podman contianer diff, does not require the --external flag, since it
there is little change of users making the mistake, and would just be a pain
for the user to remember the flag.

podman container exists --external is required because it could fool scripts
that rely on the existance of a Podman container, and there is a potential
for a partial deletion of a container, which could mess up existing users.

Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>

15 files changed, 121 insertions, 65 deletions

diff --git a/cmd/podman/containers/exists.go b/cmd/podman/containers/exists.go
index 283f6df18..1d79b684d 100644
--- a/cmd/podman/containers/exists.go
+++ b/cmd/podman/containers/exists.go
@@ -12,10 +12,10 @@ var (
 	containerExistsDescription = `If the named container exists in local storage, podman container exists exits with 0, otherwise the exit code will be 1.`
 
 	existsCommand = &cobra.Command{
-		Use:   "exists CONTAINER",
+		Use:   "exists [flags] CONTAINER",
 		Short: "Check if a container exists in local storage",
 		Long:  containerExistsDescription,
-		Example: `podman container exists containerID
+		Example: `podman container exists --external containerID
   podman container exists myctr || podman run --name myctr [etc...]`,
 		RunE:                  exists,
 		Args:                  cobra.ExactArgs(1),
@@ -29,10 +29,19 @@ func init() {
 		Command: existsCommand,
 		Parent:  containerCmd,
 	})
+	flags := existsCommand.Flags()
+	flags.Bool("external", false, "Check external storage containers as well as Podman containers")
 }
 
 func exists(cmd *cobra.Command, args []string) error {
-	response, err := registry.ContainerEngine().ContainerExists(context.Background(), args[0])
+	external, err := cmd.Flags().GetBool("external")
+	if err != nil {
+		return err
+	}
+	options := entities.ContainerExistsOptions{
+		External: external,
+	}
+	response, err := registry.ContainerEngine().ContainerExists(context.Background(), args[0], options)
 	if err != nil {
 		return err
 	}
diff --git a/cmd/podman/containers/ps.go b/cmd/podman/containers/ps.go
index 65bfc97da..41d309f51 100644
--- a/cmd/podman/containers/ps.go
+++ b/cmd/podman/containers/ps.go
@@ -58,7 +58,7 @@ func init() {
 func listFlagSet(flags *pflag.FlagSet) {
 	flags.BoolVarP(&listOpts.All, "all", "a", false, "Show all the containers, default is only running containers")
 	flags.StringSliceVarP(&filters, "filter", "f", []string{}, "Filter output based on conditions given")
-	flags.BoolVar(&listOpts.Storage, "storage", false, "Show containers in storage not controlled by Podman")
+	flags.BoolVar(&listOpts.Storage, "external", false, "Show containers in storage not controlled by Podman")
 	flags.StringVar(&listOpts.Format, "format", "", "Pretty-print containers to JSON or using a Go template")
 	flags.IntVarP(&listOpts.Last, "last", "n", -1, "Print the n last created containers (all states)")
 	flags.BoolVar(&listOpts.Namespace, "ns", false, "Display namespace information")
diff --git a/cmd/podman/diff.go b/cmd/podman/diff.go
index 51a04bf46..9d2236abe 100644
--- a/cmd/podman/diff.go
+++ b/cmd/podman/diff.go
@@ -48,7 +48,10 @@ func diff(cmd *cobra.Command, args []string) error {
 		return containers.Diff(cmd, args, diffOpts)
 	}
 
-	if found, err := registry.ContainerEngine().ContainerExists(registry.GetContext(), args[0]); err != nil {
+	options := entities.ContainerExistsOptions{
+		External: true,
+	}
+	if found, err := registry.ContainerEngine().ContainerExists(registry.GetContext(), args[0], options); err != nil {
 		return err
 	} else if found.Value {
 		return containers.Diff(cmd, args, diffOpts)
diff --git a/cmd/podman/utils/alias.go b/cmd/podman/utils/alias.go
index ff31e82ea..10b96fa98 100644
--- a/cmd/podman/utils/alias.go
+++ b/cmd/podman/utils/alias.go
@@ -21,6 +21,8 @@ func AliasFlags(f *pflag.FlagSet, name string) pflag.NormalizedName {
 		name = "time"
 	case "namespace":
 		name = "ns"
+	case "storage":
+		name = "external"
 	}
 	return pflag.NormalizedName(name)
 }
diff --git a/completions/bash/podman b/completions/bash/podman
index 564d35f67..9ed64ce3a 100644
--- a/completions/bash/podman
+++ b/completions/bash/podman
@@ -2468,7 +2468,6 @@ _podman_rm() {
 	-i
 	--latest
 	-l
-	--storage
 	--volumes
 	-v
     "
@@ -2696,7 +2695,7 @@ _podman_ps() {
 	  --pod -p
 	  --quiet -q
 	  --size -s
-	  --storage
+	  --external
 	  --namespace --ns
 	  --sync
      "
@@ -3168,7 +3167,11 @@ _podman_container_exists() {
     "
 
     local boolean_options="
-  "
+	  --external
+	  -h
+	  --help
+    "
+
     case "$cur" in
 	-*)
 	    COMPREPLY=($(compgen -W "$boolean_options $options_with_args" -- "$cur"))
diff --git a/docs/source/markdown/podman-container-exists.1.md b/docs/source/markdown/podman-container-exists.1.md
index b8be07cb9..3d151cfce 100644
--- a/docs/source/markdown/podman-container-exists.1.md
+++ b/docs/source/markdown/podman-container-exists.1.md
@@ -4,7 +4,7 @@
 podman-container-exists - Check if a container exists in local storage
 
 ## SYNOPSIS
-**podman container exists** *container*
+**podman container exists** [*options*] *container*
 
 ## DESCRIPTION
 **podman container exists** checks if a container exists in local storage. The **ID** or **Name**
@@ -14,6 +14,9 @@ was an issue accessing the local storage.
 
 ## OPTIONS
 
+**--external**=*true|false*
+Check for external containers as well as Podman containers. These external containers are generally created via other container technology such as Buildah or CRI-O.
+
 **-h**, **--help**
 Print usage statement
 
@@ -33,6 +36,13 @@ $ echo $?
 1
 ```
 
+Check if an container called `ubi8-working-container` created via Buildah exists in local storage (the container does not actually exist).
+```
+$ podman container exists --external ubi8-working-container
+$ echo $?
+1
+```
+
 ## SEE ALSO
 podman(1)
 
diff --git a/docs/source/markdown/podman-ps.1.md b/docs/source/markdown/podman-ps.1.md
index 58d3358e5..90f147222 100644
--- a/docs/source/markdown/podman-ps.1.md
+++ b/docs/source/markdown/podman-ps.1.md
@@ -34,23 +34,33 @@ all the containers information.  By default it lists:
 
 Show all the containers created by Podman, default is only running containers.
 
-Note: Podman shares containers storage with other tools such as Buildah and CRI-O. In some cases these `external` containers might also exist in the same storage. Use the `--storage` option to see these external containers. External containers show the 'storage' status.
+Note: Podman shares containers storage with other tools such as Buildah and CRI-O. In some cases these `external` containers might also exist in the same storage. Use the `--external` option to see these external containers. External containers show the 'storage' status.
 
-**--pod**, **-p**
-
-Display the pods the containers are associated with
-
-**--storage**
+**--external**
 
 Display external containers that are not controlled by Podman but are stored in containers storage.  These external containers are generally created via other container technology such as Buildah or CRI-O and may depend on the same container images that Podman is also using.  External containers are denoted with either a 'buildah' or 'storage' in the COMMAND and STATUS column of the ps output. Only used with the --all option.
 
-**--no-trunc**
+**--filter**, **-f**
 
-Display the extended information
+Filter what containers are shown in the output.
+Multiple filters can be given with multiple uses of the --filter flag.
+If multiple filters are given, only containers which match all of the given filters will be shown.
+Results will be drawn from all containers, regardless of whether --all was given.
 
-**--quiet**, **-q**
+Valid filters are listed below:
 
-Print the numeric IDs of the containers only
+| **Filter**      | **Description**                                                                  |
+| --------------- | -------------------------------------------------------------------------------- |
+| id              | [ID] Container's ID                                                              |
+| name            | [Name] Container's name                                                          |
+| label           | [Key] or [Key=Value] Label assigned to a container                               |
+| exited          | [Int] Container's exit code                                                      |
+| status          | [Status] Container's status: 'created', 'exited', 'paused', 'running', 'unknown' |
+| ancestor        | [ImageName] Image or descendant used to create container                         |
+| before          | [ID] or [Name] Containers created before this container                          |
+| since           | [ID] or [Name] Containers created since this container                           |
+| volume          | [VolumeName] or [MountpointDestination] Volume mounted in container              |
+| health          | [Status] healthy or unhealthy                                                    |
 
 **--format**=*format*
 
@@ -74,15 +84,9 @@ Valid placeholders for the Go template are listed below:
 | .Labels         | All the labels assigned to the container         |
 | .Mounts         | Volumes mounted in the container                 |
 
-**--sort**
-
-Sort by command, created, id, image, names, runningfor, size, or status",
-Note: Choosing size will sort by size of rootFs, not alphabetically like the rest of the options
-Default: created
-
-**--size**, **-s**
+**--help**, **-h**
 
-Display the total file size
+Print usage statement
 
 **--last**, **-n**
 
@@ -98,31 +102,27 @@ The latest option is not supported on the remote client.
 
 Display namespace information
 
-**--filter**, **-f**
+**--no-trunc**
 
-Filter what containers are shown in the output.
-Multiple filters can be given with multiple uses of the --filter flag.
-If multiple filters are given, only containers which match all of the given filters will be shown.
-Results will be drawn from all containers, regardless of whether --all was given.
+Display the extended information
 
-Valid filters are listed below:
+**--pod**, **-p**
 
-| **Filter**      | **Description**                                                                  |
-| --------------- | -------------------------------------------------------------------------------- |
-| id              | [ID] Container's ID                                                              |
-| name            | [Name] Container's name                                                          |
-| label           | [Key] or [Key=Value] Label assigned to a container                               |
-| exited          | [Int] Container's exit code                                                      |
-| status          | [Status] Container's status: 'created', 'exited', 'paused', 'running', 'unknown' |
-| ancestor        | [ImageName] Image or descendant used to create container                         |
-| before          | [ID] or [Name] Containers created before this container                          |
-| since           | [ID] or [Name] Containers created since this container                           |
-| volume          | [VolumeName] or [MountpointDestination] Volume mounted in container              |
-| health          | [Status] healthy or unhealthy                                                    |
+Display the pods the containers are associated with
 
-**--help**, **-h**
+**--quiet**, **-q**
 
-Print usage statement
+Print the numeric IDs of the containers only
+
+**--sort**
+
+Sort by command, created, id, image, names, runningfor, size, or status",
+Note: Choosing size will sort by size of rootFs, not alphabetically like the rest of the options
+Default: created
+
+**--size**, **-s**
+
+Display the total file size
 
 **--sync**
 
@@ -181,7 +181,7 @@ CONTAINER ID  IMAGE                            COMMAND    CREATED        STATUS
 ```
 
 ```
-$ podman ps --storage -a
+$ podman ps --external -a
 CONTAINER ID  IMAGE                             COMMAND  CREATED      STATUS  PORTS  NAMES
 69ed779d8ef9f  redis:alpine  "redis-server"  25 hours ago  Created                   6379/tcp  k8s_container1_podsandbox1_redhat.test.crio_redhat-test-crio_1
 38a8a78596f9  docker.io/library/busybox:latest  buildah  2 hours ago  storage        busybox-working-container
diff --git a/pkg/api/handlers/libpod/containers.go b/pkg/api/handlers/libpod/containers.go
index 8068ea1b8..7e6481321 100644
--- a/pkg/api/handlers/libpod/containers.go
+++ b/pkg/api/handlers/libpod/containers.go
@@ -19,13 +19,30 @@ import (
 )
 
 func ContainerExists(w http.ResponseWriter, r *http.Request) {
+	decoder := r.Context().Value("decoder").(*schema.Decoder)
 	runtime := r.Context().Value("runtime").(*libpod.Runtime)
 	// Now use the ABI implementation to prevent us from having duplicate
 	// code.
 	containerEngine := abi.ContainerEngine{Libpod: runtime}
 
 	name := utils.GetName(r)
-	report, err := containerEngine.ContainerExists(r.Context(), name)
+	query := struct {
+		External bool `schema:"external"`
+	}{
+		// override any golang type defaults
+	}
+
+	if err := decoder.Decode(&query, r.URL.Query()); err != nil {
+		utils.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest,
+			errors.Wrapf(err, "failed to parse parameters for %s", r.URL.String()))
+		return
+	}
+
+	options := entities.ContainerExistsOptions{
+		External: query.External,
+	}
+
+	report, err := containerEngine.ContainerExists(r.Context(), name, options)
 	if err != nil {
 		if errors.Cause(err) == define.ErrNoSuchCtr {
 			utils.ContainerNotFound(w, name, err)
diff --git a/pkg/bindings/containers/containers.go b/pkg/bindings/containers/containers.go
index 708ad06cb..b5cd2128b 100644
--- a/pkg/bindings/containers/containers.go
+++ b/pkg/bindings/containers/containers.go
@@ -322,12 +322,14 @@ func Wait(ctx context.Context, nameOrID string, condition *define.ContainerStatu
 // Exists is a quick, light-weight way to determine if a given container
 // exists in local storage.  The nameOrID can be a container name
 // or a partial/full ID.
-func Exists(ctx context.Context, nameOrID string) (bool, error) {
+func Exists(ctx context.Context, nameOrID string, external bool) (bool, error) {
 	conn, err := bindings.GetClient(ctx)
 	if err != nil {
 		return false, err
 	}
-	response, err := conn.DoRequest(nil, http.MethodGet, "/containers/%s/exists", nil, nil, nameOrID)
+	params := url.Values{}
+	params.Set("external", strconv.FormatBool(external))
+	response, err := conn.DoRequest(nil, http.MethodGet, "/containers/%s/exists", params, nil, nameOrID)
 	if err != nil {
 		return false, err
 	}
diff --git a/pkg/bindings/test/containers_test.go b/pkg/bindings/test/containers_test.go
index 408b4769d..0fb677768 100644
--- a/pkg/bindings/test/containers_test.go
+++ b/pkg/bindings/test/containers_test.go
@@ -405,7 +405,7 @@ var _ = Describe("Podman containers ", func() {
 
 	It("podman bogus container does not exist in local storage", func() {
 		// Bogus container existence check should fail
-		containerExists, err := containers.Exists(bt.conn, "foobar")
+		containerExists, err := containers.Exists(bt.conn, "foobar", false)
 		Expect(err).To(BeNil())
 		Expect(containerExists).To(BeFalse())
 	})
@@ -415,7 +415,7 @@ var _ = Describe("Podman containers ", func() {
 		var name = "top"
 		_, err := bt.RunTopContainer(&name, bindings.PFalse, nil)
 		Expect(err).To(BeNil())
-		containerExists, err := containers.Exists(bt.conn, name)
+		containerExists, err := containers.Exists(bt.conn, name, false)
 		Expect(err).To(BeNil())
 		Expect(containerExists).To(BeTrue())
 	})
@@ -425,7 +425,7 @@ var _ = Describe("Podman containers ", func() {
 		var name = "top"
 		cid, err := bt.RunTopContainer(&name, bindings.PFalse, nil)
 		Expect(err).To(BeNil())
-		containerExists, err := containers.Exists(bt.conn, cid)
+		containerExists, err := containers.Exists(bt.conn, cid, false)
 		Expect(err).To(BeNil())
 		Expect(containerExists).To(BeTrue())
 	})
@@ -435,7 +435,7 @@ var _ = Describe("Podman containers ", func() {
 		var name = "top"
 		cid, err := bt.RunTopContainer(&name, bindings.PFalse, nil)
 		Expect(err).To(BeNil())
-		containerExists, err := containers.Exists(bt.conn, cid[0:12])
+		containerExists, err := containers.Exists(bt.conn, cid[0:12], false)
 		Expect(err).To(BeNil())
 		Expect(containerExists).To(BeTrue())
 	})
@@ -455,7 +455,7 @@ var _ = Describe("Podman containers ", func() {
 		Expect(err).To(BeNil())
 		err = containers.Kill(bt.conn, name, "SIGINT")
 		Expect(err).To(BeNil())
-		_, err = containers.Exists(bt.conn, name)
+		_, err = containers.Exists(bt.conn, name, false)
 		Expect(err).To(BeNil())
 	})
 
@@ -466,7 +466,7 @@ var _ = Describe("Podman containers ", func() {
 		Expect(err).To(BeNil())
 		err = containers.Kill(bt.conn, cid, "SIGTERM")
 		Expect(err).To(BeNil())
-		_, err = containers.Exists(bt.conn, cid)
+		_, err = containers.Exists(bt.conn, cid, false)
 		Expect(err).To(BeNil())
 	})
 
diff --git a/pkg/domain/entities/containers.go b/pkg/domain/entities/containers.go
index 3b6dd106f..46b169284 100644
--- a/pkg/domain/entities/containers.go
+++ b/pkg/domain/entities/containers.go
@@ -246,6 +246,11 @@ type ExecOptions struct {
 	WorkDir     string
 }
 
+// ContainerExistsOptions describes the cli values to check if a container exists
+type ContainerExistsOptions struct {
+	External bool
+}
+
 // ContainerStartOptions describes the val from the
 // CLI needed to start a container
 type ContainerStartOptions struct {
diff --git a/pkg/domain/entities/engine_container.go b/pkg/domain/entities/engine_container.go
index 803a59932..a20d3b404 100644
--- a/pkg/domain/entities/engine_container.go
+++ b/pkg/domain/entities/engine_container.go
@@ -21,7 +21,7 @@ type ContainerEngine interface {
 	ContainerDiff(ctx context.Context, nameOrID string, options DiffOptions) (*DiffReport, error)
 	ContainerExec(ctx context.Context, nameOrID string, options ExecOptions, streams define.AttachStreams) (int, error)
 	ContainerExecDetached(ctx context.Context, nameOrID string, options ExecOptions) (string, error)
-	ContainerExists(ctx context.Context, nameOrID string) (*BoolReport, error)
+	ContainerExists(ctx context.Context, nameOrID string, options ContainerExistsOptions) (*BoolReport, error)
 	ContainerExport(ctx context.Context, nameOrID string, options ContainerExportOptions) error
 	ContainerInit(ctx context.Context, namesOrIds []string, options ContainerInitOptions) ([]*ContainerInitReport, error)
 	ContainerInspect(ctx context.Context, namesOrIds []string, options InspectOptions) ([]*ContainerInspectReport, []error, error)
diff --git a/pkg/domain/infra/abi/containers.go b/pkg/domain/infra/abi/containers.go
index 191ad8eec..60dbbce6c 100644
--- a/pkg/domain/infra/abi/containers.go
+++ b/pkg/domain/infra/abi/containers.go
@@ -75,15 +75,17 @@ func getContainersByContext(all, latest bool, names []string, runtime *libpod.Ru
 }
 
 // ContainerExists returns whether the container exists in container storage
-func (ic *ContainerEngine) ContainerExists(ctx context.Context, nameOrID string) (*entities.BoolReport, error) {
+func (ic *ContainerEngine) ContainerExists(ctx context.Context, nameOrID string, options entities.ContainerExistsOptions) (*entities.BoolReport, error) {
 	_, err := ic.Libpod.LookupContainer(nameOrID)
 	if err != nil {
 		if errors.Cause(err) != define.ErrNoSuchCtr {
 			return nil, err
 		}
-		// Check if container exists in storage
-		if _, storageErr := ic.Libpod.StorageContainer(nameOrID); storageErr == nil {
-			err = nil
+		if options.External {
+			// Check if container exists in storage
+			if _, storageErr := ic.Libpod.StorageContainer(nameOrID); storageErr == nil {
+				err = nil
+			}
 		}
 	}
 	return &entities.BoolReport{Value: err == nil}, nil
diff --git a/pkg/domain/infra/tunnel/containers.go b/pkg/domain/infra/tunnel/containers.go
index 1bb4e68ac..98e30c83d 100644
--- a/pkg/domain/infra/tunnel/containers.go
+++ b/pkg/domain/infra/tunnel/containers.go
@@ -29,8 +29,8 @@ func (ic *ContainerEngine) ContainerRunlabel(ctx context.Context, label string,
 	return errors.New("not implemented")
 }
 
-func (ic *ContainerEngine) ContainerExists(ctx context.Context, nameOrID string) (*entities.BoolReport, error) {
-	exists, err := containers.Exists(ic.ClientCxt, nameOrID)
+func (ic *ContainerEngine) ContainerExists(ctx context.Context, nameOrID string, options entities.ContainerExistsOptions) (*entities.BoolReport, error) {
+	exists, err := containers.Exists(ic.ClientCxt, nameOrID, options.External)
 	return &entities.BoolReport{Value: exists}, err
 }
 
diff --git a/test/system/030-run.bats b/test/system/030-run.bats
index a82743c70..f7c48da8d 100644
--- a/test/system/030-run.bats
+++ b/test/system/030-run.bats
@@ -471,8 +471,11 @@ json-file | f
     run buildah from $IMAGE
     cid="$output"
 
+    # exists should fail
+    run_podman 1 container exists $cid
+
     # exists should succeed
-    run_podman container exists $cid
+    run_podman container exists --external $cid
 
     run buildah rm $cid
 }