diff options
| -rw-r--r-- | cmd/podmanV2/README.md | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/cmd/podmanV2/README.md b/cmd/podmanV2/README.md new file mode 100644 index 000000000..a17e6f850 --- /dev/null +++ b/cmd/podmanV2/README.md @@ -0,0 +1,113 @@ +# Adding a podman V2 commands + +## Build podman V2 + +```shell script +$ cd $GOPATH/src/github.com/containers/libpod/cmd/podmanV2 +``` +If you wish to include the libpod library in your program, +```shell script +$ go build -tags 'ABISupport' . +``` +The `--remote` flag may be used to connect to the Podman service using the API. +Otherwise, direct calls will be made to the Libpod library. +```shell script +$ go build -tags '!ABISupport' . +``` +The Libpod library is not linked into the executable. +All calls are made via the API and `--remote=False` is an error condition. + +## Adding a new command `podman manifests` +```shell script +$ mkdir -p $GOPATH/src/github.com/containers/libpod/cmd/podmanV2/manifests +``` +Create the file ```$GOPATH/src/github.com/containers/libpod/cmd/podmanV2/manifests/manifest.go``` +```go +package manifests + +import ( + "github.com/containers/libpod/cmd/podmanV2/registry" + "github.com/containers/libpod/pkg/domain/entities" + "github.com/spf13/cobra" +) + +var ( + // podman _manifests_ + manifestCmd = &cobra.Command{ + Use: "manifest", + Short: "Manage manifests", + Long: "Manage manifests", + Example: "podman manifests IMAGE", + TraverseChildren: true, + PersistentPreRunE: preRunE, + RunE: registry.SubCommandExists, // Report error if there is no sub command given + } +) +func init() { + // Subscribe command to podman + registry.Commands = append(registry.Commands, registry.CliCommand{ + // _podman manifest_ will support both ABIMode and TunnelMode + Mode: []entities.EngineMode{entities.ABIMode, entities.TunnelMode}, + // The definition for this command + Command: manifestCmd, + }) + // Setup cobra templates, sub commands will inherit + manifestCmd.SetHelpTemplate(registry.HelpTemplate()) + manifestCmd.SetUsageTemplate(registry.UsageTemplate()) +} + +// preRunE populates the image engine for sub commands +func preRunE(cmd *cobra.Command, args []string) error { + _, err := registry.NewImageEngine(cmd, args) + return err +} +``` +To "wire" in the `manifest` command, edit the file ```$GOPATH/src/github.com/containers/libpod/cmd/podmanV2/main.go``` to add: +```go +package main + +import _ "github.com/containers/libpod/cmd/podmanV2/manifests" +``` + +## Adding a new sub command `podman manifests list` +Create the file ```$GOPATH/src/github.com/containers/libpod/cmd/podmanV2/manifests/inspect.go``` +```go +package manifests + +import ( + "github.com/containers/libpod/cmd/podmanV2/registry" + "github.com/containers/libpod/pkg/domain/entities" + "github.com/spf13/cobra" +) + +var ( + // podman manifests _inspect_ + inspectCmd = &cobra.Command{ + Use: "inspect IMAGE", + Short: "Display manifest from image", + Long: "Displays the low-level information on a manifest identified by image name or ID", + RunE: inspect, + Example: "podman manifest DEADBEEF", + } +) + +func init() { + // Subscribe inspect sub command to manifest command + registry.Commands = append(registry.Commands, registry.CliCommand{ + // _podman manifest inspect_ will support both ABIMode and TunnelMode + Mode: []entities.EngineMode{entities.ABIMode, entities.TunnelMode}, + // The definition for this command + Command: inspectCmd, + Parent: manifestCmd, + }) + + // This is where you would configure the cobra flags using inspectCmd.Flags() +} + +// Business logic: cmd is inspectCmd, args is the positional arguments from os.Args +func inspect(cmd *cobra.Command, args []string) error { + // Business logic using registry.ImageEngine + // Do not pull from libpod directly use the domain objects and types + return nil +} +``` |