Add shell completion with cobra

Allow automatic generation for shell completion scripts
with the internal cobra functions (requires v1.0.0+).

This should replace the handwritten completion scripts
and even adds support for fish. With this approach it is
less likley that completions and code are out of sync.

We can now create the scripts with
- podman completion bash
- podman completion zsh
- podman completion fish

To test the completion run:
source <(podman completion bash)

The same works for podman-remote and podman --remote and
it will complete your remote containers/images with
the correct endpoints values from --url/--connection.

The completion logic is written in go and provided by the
cobra library. The completion functions lives in
`cmd/podman/completion/completion.go`.

The unit test at cmd/podman/shell_completion_test.go checks
if each command and flag has an autocompletion function set.
This prevents that commands and flags have no shell completion set.

This commit does not replace the current autocompletion scripts.

Closes #6440

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

1 files changed, 44 insertions, 14 deletions

diff --git a/cmd/podman/manifest/add.go b/cmd/podman/manifest/add.go
index 4b85f4c2a..91bd423b8 100644
--- a/cmd/podman/manifest/add.go
+++ b/cmd/podman/manifest/add.go
@@ -5,7 +5,9 @@ import (
 	"fmt"
 
 	"github.com/containers/common/pkg/auth"
+	"github.com/containers/common/pkg/completion"
 	"github.com/containers/image/v5/types"
+	"github.com/containers/podman/v2/cmd/podman/common"
 	"github.com/containers/podman/v2/cmd/podman/registry"
 	"github.com/containers/podman/v2/pkg/domain/entities"
 	"github.com/containers/podman/v2/pkg/util"
@@ -25,10 +27,11 @@ type manifestAddOptsWrapper struct {
 var (
 	manifestAddOpts = manifestAddOptsWrapper{}
 	addCmd          = &cobra.Command{
-		Use:   "add [options] LIST LIST",
-		Short: "Add images to a manifest list or image index",
-		Long:  "Adds an image to a manifest list or image index.",
-		RunE:  add,
+		Use:               "add [options] LIST LIST",
+		Short:             "Add images to a manifest list or image index",
+		Long:              "Adds an image to a manifest list or image index.",
+		RunE:              add,
+		ValidArgsFunction: common.AutocompleteImages,
 		Example: `podman manifest add mylist:v1.11 image:v1.11-amd64
 		podman manifest add mylist:v1.11 transport:imageName`,
 		Args: cobra.ExactArgs(2),
@@ -43,17 +46,44 @@ func init() {
 	})
 	flags := addCmd.Flags()
 	flags.BoolVar(&manifestAddOpts.All, "all", false, "add all of the list's images if the image is a list")
-	flags.StringSliceVar(&manifestAddOpts.Annotation, "annotation", nil, "set an `annotation` for the specified image")
-	flags.StringVar(&manifestAddOpts.Arch, "arch", "", "override the `architecture` of the specified image")
-	flags.StringVar(&manifestAddOpts.Authfile, "authfile", auth.GetDefaultAuthFile(), "path of the authentication file. Use REGISTRY_AUTH_FILE environment variable to override")
-	flags.StringVar(&manifestAddOpts.CertDir, "cert-dir", "", "use certificates at the specified path to access the registry")
-	flags.StringVar(&manifestAddOpts.CredentialsCLI, "creds", "", "use `[username[:password]]` for accessing the registry")
-
-	flags.StringSliceVar(&manifestAddOpts.Features, "features", nil, "override the `features` of the specified image")
-	flags.StringVar(&manifestAddOpts.OS, "os", "", "override the `OS` of the specified image")
-	flags.StringVar(&manifestAddOpts.OSVersion, "os-version", "", "override the OS `version` of the specified image")
+
+	annotationFlagName := "annotation"
+	flags.StringSliceVar(&manifestAddOpts.Annotation, annotationFlagName, nil, "set an `annotation` for the specified image")
+	_ = addCmd.RegisterFlagCompletionFunc(annotationFlagName, completion.AutocompleteNone)
+
+	archFlagName := "arch"
+	flags.StringVar(&manifestAddOpts.Arch, archFlagName, "", "override the `architecture` of the specified image")
+	_ = addCmd.RegisterFlagCompletionFunc(archFlagName, completion.AutocompleteNone)
+
+	authfileFlagName := "authfile"
+	flags.StringVar(&manifestAddOpts.Authfile, authfileFlagName, auth.GetDefaultAuthFile(), "path of the authentication file. Use REGISTRY_AUTH_FILE environment variable to override")
+	_ = addCmd.RegisterFlagCompletionFunc(authfileFlagName, completion.AutocompleteDefault)
+
+	certDirFlagName := "cert-dir"
+	flags.StringVar(&manifestAddOpts.CertDir, certDirFlagName, "", "use certificates at the specified path to access the registry")
+	_ = addCmd.RegisterFlagCompletionFunc(certDirFlagName, completion.AutocompleteDefault)
+
+	credsFlagName := "creds"
+	flags.StringVar(&manifestAddOpts.CredentialsCLI, credsFlagName, "", "use `[username[:password]]` for accessing the registry")
+	_ = addCmd.RegisterFlagCompletionFunc(credsFlagName, completion.AutocompleteNone)
+
+	featuresFlagName := "features"
+	flags.StringSliceVar(&manifestAddOpts.Features, featuresFlagName, nil, "override the `features` of the specified image")
+	_ = addCmd.RegisterFlagCompletionFunc(featuresFlagName, completion.AutocompleteNone)
+
+	osFlagName := "os"
+	flags.StringVar(&manifestAddOpts.OS, osFlagName, "", "override the `OS` of the specified image")
+	_ = addCmd.RegisterFlagCompletionFunc(osFlagName, completion.AutocompleteNone)
+
+	osVersionFlagName := "os-version"
+	flags.StringVar(&manifestAddOpts.OSVersion, osVersionFlagName, "", "override the OS `version` of the specified image")
+	_ = addCmd.RegisterFlagCompletionFunc(osVersionFlagName, completion.AutocompleteNone)
+
 	flags.BoolVar(&manifestAddOpts.TLSVerifyCLI, "tls-verify", true, "require HTTPS and verify certificates when accessing the registry")
-	flags.StringVar(&manifestAddOpts.Variant, "variant", "", "override the `Variant` of the specified image")
+
+	variantFlagName := "variant"
+	flags.StringVar(&manifestAddOpts.Variant, variantFlagName, "", "override the `Variant` of the specified image")
+	_ = addCmd.RegisterFlagCompletionFunc(variantFlagName, completion.AutocompleteNone)
 
 	if registry.IsRemote() {
 		_ = flags.MarkHidden("cert-dir")