• UnifiedCommandLineClient

OpenStack Unified Client

Working with multiple OpenStack projects can be quite tedious as they all have their own command-line tools. Having a single command-line interface (CLI) will help to unify project developers, reduce operational headaches, and provide users with a better overall experience.

Start with Authentication / Authorization

If the first step, when calling our unified CLI, is to authenticate against a provided authentication endpoint (managed by a Keystone-compaible service), then right away feedback can be given to the user regarding which services are available for use.

For example, if incorrect authentication is given, or an invalid/inaccessible URL is given:

$ os
usage: os [--url URL] [--username USERNAME] [--apikey APIKEY] [--project PROJECT]

Command-line interface for connecting to various OpenStack projects.

Correct authentication URL and credentials must be supplied before more detailed options can be given.

Once valid authentication information is given, we can provide the user with a better overview of available services:

$ os
usage: os <project>

Command-line interface for connecting to various OpenStack projects.

Supported projects:
        compute         Manage compute nodes via the "Nova" API.
        image           Manage disk images via the "Glance" API.
        queue           Manage queues via the "Burrow" API.
        volume          Manage remote disk volumes via the "Lunr" API.
        auth            Manage authentication and authorization via the "Keystone" API.
        network         Manage networks via the "Melange" API.

The list of services above is generated by reading the service catalog provided by a Keystone-based service, which currently looks something like this:

{
    "auth":{
        "token":{
            "id":"asdasdasd-adsasdads-asdasdasd-adsadsasd",
            "expires":"2010-11-01T03:32:15-05:00"
        },
        "serviceCatalog":{
            "service1":[
                {
                    "region":"DFW",
                    "publicURL":"https://service1-public/v1/blah-blah",
                    "internalURL":"https://service1-internal/v1/blah-blah"
                },
                {
                    "region":"ORD",
                    "publicURL":"https://service1-public-ord/v1/blah-blah",
                    "internalURL":"https://service1-internal-ord/v1/blah-blah"
                }
            ],
            "service2":[
                {
                    "region":"DFW",
                    "publicURL":"https://service2-public-dfw/v1/blah-blah"
                },
                {
                    "region":"ORD",
                    "publicURL":"https://service2-public-orf/v1/blah-blah"
                }
            ],
            "service3":[
                {
                    "publicURL":"https://service3-public/v1/blah-blah"
                }
            ]
        }
    }
}

When a service is selected on the command line, detailed information will be generated based on the authorization of the currently authenticated user. For example:

$ os compute
usage: os compute <command>

Command-line interface for retrieving information from an OpenStack Compute service.

Supported API versions:
        --version=1.0 
        --version=1.1 [Default]

Supported commands:
        boot                    Boot a new server.
        delete                  Shut down and delete a server.
        flavor-list             Print a list of available 'flavors'.
        image-list              Print a list of available disk images.
        snapshot                Create a new disk image based on a currently
                                running server.
        list                    List active servers.
        reboot                  Reboot a server.
        rebuild                 Shutdown, re-image, and re-boot a server.
        rename                  Rename a server.
        resize                  Begin the resize process.
        resize-confirm          Confirm a previously started resize.
        resize-revert           Revert a previously started resize.

        admin:diagnostics       Retrieve server diagnostics.
        admin:boot              Boot a new server, with extra options.
        admin:lock              Lock a server, preventing any changes.
        admin:unlock            Remove server lock, allowing future changes.

        zone:list               List zones underneath this endpoint.
        zone:info               Get information on this endpoint's zone.
        zone:add                Add a new child zone underneath this endpoint.

We can see that this user has access to many run-of-the-mill Compute tasks, but they are also authorized to use functions from the "Compute Administrative Extension" and the "Compute Zones Extension". You can tell that these commands are provided by extensions because they are prefixed with a relevant...prefix.

Required Options

I understand the irony (?) of having required options, but they're not technically required because they'll default to environmental variables, so having them as command line arguments is not an option.

Potential Issues

• An implementation of this might be slow before caching is involved because even the error response views above require a round-trip talk with one or more OpenStack services. Caching solves this, but caching shouldn't be considered for the first release of this client.

• Currently Keystone seems to be returning versioned service URLs. For example, the service catalog might return http://openstack.org/compute/v1.1 instead of http://openstack.org/compute/. The client should be able to choose a version just as they are currently able to choose a region.