podman manifest exists

Add podman manifest exists command with remote support.

Signed-off-by: Paul Holzinger <paul.holzinger@web.de>

docs/source/manifest.rst

@@ -7,6 +7,8 @@ Create and manipulate manifest lists and image indexes
 
 :doc:`create <markdown/podman-manifest-create.1>` Create a manifest list or image index
 
+:doc:`exists <markdown/podman-manifest-exists.1>` Check if the given manifest list exists in local storage
+
 :doc:`inspect <markdown/podman-manifest-inspect.1>` Display a manifest list or image index
 
 :doc:`push <markdown/podman-manifest-push.1>` Push a manifest list or image index to a registry

docs/source/markdown/podman-manifest-exists.1.md

@@ -0,0 +1,43 @@
+% podman-manifest-exists(1)
+
+## NAME
+podman\-manifest\-exists - Check if the given manifest list exists in local storage
+
+## SYNOPSIS
+**podman manifest exists** *manifest*
+
+## DESCRIPTION
+**podman manifest exists** checks if a manifest list exists on local storage. Podman will
+return an exit code of `0` when the manifest is found. A `1` will be returned otherwise.
+An exit code of `125` indicates there was another issue.
+
+
+## OPTIONS
+
+#### **--help**, **-h**
+
+Print usage statement.
+
+## EXAMPLE
+
+Check if a manifest list called `list1` exists (the manifest list does actually exist).
+```
+$ podman manifest exists list1
+$ echo $?
+0
+$
+```
+
+Check if an manifest called `mylist` exists (the manifest list does not actually exist).
+```
+$ podman manifest exists mylist
+$ echo $?
+1
+$
+```
+
+## SEE ALSO
+podman(1), podman-manifest-create(1), podman-manifest-remove(1)
+
+## HISTORY
+January 2021, Originally compiled by Paul Holzinger `<paul.holzinger@web.de>`

docs/source/markdown/podman-manifest.1.md

@@ -18,6 +18,7 @@ The `podman manifest` command provides subcommands which can be used to:
 | add      | [podman-manifest-add(1)](podman-manifest-add.1.md)           | Add an image to a manifest list or image index.                             |
 | annotate | [podman-manifest-annotate(1)](podman-manifest-annotate.1.md) | Add or update information about an entry in a manifest list or image index. |
 | create   | [podman-manifest-create(1)](podman-manifest-create.1.md)     | Create a manifest list or image index.                                      |
+| exists   | [podman-manifest-exists(1)](podman-manifest-exists.1.md)     | Check if the given manifest list exists in local storage                    |
 | inspect  | [podman-manifest-inspect(1)](podman-manifest-inspect.1.md)   | Display a manifest list or image index.                                     |
 | push     | [podman-manifest-push(1)](podman-manifest-push.1.md)         | Push a manifest list or image index to a registry.                          |
 | remove   | [podman-manifest-remove(1)](podman-manifest-remove.1.md)     | Remove an image from a manifest list or image index.                        |